Einstein, Millikan, and the humanness of humans

It is fascinating and inspiring to study the history of science.  It is also remarkable how it is simply impossible for humans to not always be primarily driven by their humanness.  Sometimes this is incredibly useful, because it brings insights of the highest order; sometimes it is painfully debilitating, because it prevents seeing the obvious due to an intellectual stance that rejects an idea based on already acquired and strongly held notions.

To muddle the situation further, our humanness leads us to, over time, remember things in a way that suits us better right now, such that the same sequence of events are remembered and then interpreted differently depending on the circumstances, the mindset, and the knowledge as well as opinions we hold and have acquired since these events took place.

I am currently reading The Cambridge Companion to Einstein, a collection of fourteen essays by leading historians and philosophers of science that introduces his work in the historical and philosophical context in which it took shape and arose.  There are a few essays that discuss the photoelectric effect, the insight for which Einstein received his only Nobel prize.  This work of one of the most important in the history of modern physics because it was the foundation of quantum theory.  The fifth essay in the collection, The Experimental Challenge of Light Quanta, is by Roger Stuewer.

Many experimentalists ran many experiments to test Einstein’s theory that light was in fact quanta, little bundles of energy, whose energy depended only the frequency of the light with Plank’s constant as the proportionality constant: E = hv.  But surely it was Robert Millikan’s famous oil drop experiment that demonstrated beyond debate that all of Einstein’s predictions were in accordance with experimental reality.  Nevertheless, at the time, Millikan himself would not believe it.  He wrote in 1917, reflecting on his experimental testing of Einstein’s quantum theory of light that culminated in 1915:

Despite … the apparently complete success of the Einstein equation, the physical theory of which it was designed to be the symbolic expression if found so untenable that Einstein himself, I believe [my italics], no longer holds to it, and we are in the position of having build a very perfect structure and then knocked out entirely the underpinning without causing the building to fall.  It [Einstein’s equation] stands complete and apparently well tested, but without any visible means of support.  These supports must obviously exist, and the most fascinating problem of modern physics is to find them.  Experiment has outrun theory, or, better, guided by erroneous theory [Stuewer’s italics], it has discovered relationships which seem to be of the greatest interest and importance, but the reasons for them are as yet not at all understood.

But 33 years later, in his 1950 autobiography, he recalled, in a chapter entitled  The Experimental Proof of the Existence of the Photon, that at the meeting of the American Physical Society (APS) in April 1915 he presented “my complete verification of the validity of the Einstein equation” and then added:

This seemed to me, as it did to many others, a matter of very great importance, for it … proved simply and irrefutably I thought, that the emitted electron that escapes with the energy hv gets that energy by the direct transfer of hv units of energy from the light to the electron [Millikan’s italics] and hence scarcely permits of an other interpretation than that which Einstein had originally suggested, namely that of the semi-corposcular or photon theory of light itself.

What does this mean, and what does it tell us about not just Millikan, but about ourselves?  It shows us that the opinions, beliefs, ideas, notions that we hold of how things are will generally force us into a mindset that brings us to reject the obvious even in the face of “irrefutable” experimental evidence simply because we are not ready to accept it.  And it shows us that generally, each time we will recall something, each time we will bring something back from the annals of our memory, it will be reshaped by the mindset that we currently hold, which in turn is continuously reshaped and sculpted by information, acquired knowledge, and experiences we are presented with as we go about our daily lives.  This is certainly one of the hallmarks of our humanness; a hallmark of our being humans.  Is it wrong to distort history in this way?  Who’s to say.  Do we all do it?  Maybe.

How much do you weigh? (Hint: it’s a trick question)

earth-trueColors

A friend of mine called yesterday morning to ask a favour: someone he knows read a thing about the upcoming eclipse on a NASA webpage, and about what difference this would make on our weight, and got the impression that there was a mistake in their calculations. The passage was the following:

Starting as an observer on the ground, you are under the gravitational influence of Earth, the moon and the sun. At the time of the August 21, 2017 eclipse, Earth will be 151.4 million kilometers from the sun, and the moon will be located 365,649 km from the surface of Earth. Using Newton’s Law of Gravity, we can calculate the force of the sun, moon and Earth on an 80 kg person. Earth accounts for 784.1 Newtons of force (176.42 pounds), the moon provides 0.0029 Newtons (0.01 ounces) and the sun provides 0.4633 Newtons (1.6 ounces). But because our Earth rotates, this also provides an ‘anti-gravity’ centrifugal force we can also calculate. So if we add the forces with their correct directions we get a total gravitational force of 784.1 — 0.0029 — 0.4633 = 783.634 Newtons or 176.317 pounds. So, you will be about 1.7 ounces lighter!

My friend asked me to check it out and report back to him so that he could pass on the information. So I did, and I thought it might be interesting to write it up, just in case you may be interested, and in case a similar question comes up again at some point in the future. If you are interested, you can read it here.

 

Life

This morning, near the end of our walk with Coalback, I noticed something falling out of a tree. It fell straight down on the roof of a car parked on the side of the road, and bounced off onto the soil by the sidewalk. I walked up to it and saw it was a small bird. It was moving erratically, jerking its legs, trying to flap its wings, and was opening and closing its beak. It was in a panic but couldn’t really move. I took it into my hands and cradled it to make it feel secure. It relaxed its little body. Less than 30 seconds later, it stopped moving. Its neck went limp, and its little head swung out to the side. The little bird had just died in my hands. I placed it by the side of the tree, and walked home with Coalbie.

baby-pigeon

This afternoon, as we were walking up that street, I saw a magpie pecking at the bird by the side of the tree. It was eating it. As we got closer, the magpie flew up to a branch and waited. I noticed that there was another little bird just like the other one lying in the same spot I had found the first one in the morning. It was also dead. Both must have fallen out of the same nest, hit the car, bounced off onto the ground, and died a few moments later. Both had holes pecked into their bellies. I walked on with Coalback. The magpie was looking at us walk away, waiting.

Implicitly Assumed

Has it ever happened to you to be, all of a sudden, struck by the realisation that something you had always believed to be the case, turned out to be different than what you believed? Maybe some lyrics in a song, maybe something about a silhouette or a logo on a sign. In that moment, what you realised was first that you were holding an assumption about something without knowing you were, and second that this assumption you held implicitly was wrong—it didn’t accord with the way things are in reality.

I think that one of the greatest difficulties we have in science is to avoid biasing our results and their interpretation based on these kinds of assumptions we hold implicitly. We learn that we should always be absolutely clear about the assumptions we make and state them upfront. And we do this. This is not the issue I am addressing here. The real problem is that of assumptions we are not aware we are making. And we are not aware because we either have no idea we are making that assumption, or because we have long ago forgotten that the method we are using in our analysis has a particular assumption that is embedded within it. Here is what I mean.

We have three scientists working with the same data set. The data was collected during a 10000 second observation of a star with an X-ray satellite and consists of a list of 5063 detected photons. This gives a mean count rate of 0.5063 counts per second, so basically, the detector was getting one X-ray photon every couple of seconds. Taking this list of times at which each of these 5063 photons was detected and going through it to count the number of X-rays per interval of 20 seconds, say, and then plotting the number of photons per interval on a time line, we construct a time series that is also call a light curve in astronomy and astrophysics. It looks like this:

ts

X-ray time series of 5063 photons detected during a 10 ks observation and grouped in 20 s bins.

As you can see, it is rather unremarkable: a constant intensity with some fluctuations that all look pretty much like what we expect the statistical fluctuations to look like for a non-variable star. The way to look in more detail at the repartition of detected events in time, and in particular, to look for signs of periodic activity where something in the system would lead to regular, cyclical changes in the intensity, is to transform this intensity as a function of time into something that is a function of frequency. This is a mathematical operation that was discovered by Joseph Fourier and it is called a Fourier transform. The reason we can go back and forth from the time domain to the frequency domain with a Fourier transform to go from time to frequency and the inverse transform to go from frequency to time, is that they are two equivalent ways of presenting the same information, and there is no loss of information in going from one to the other.

The major difference between the time series and the periodogram is that in the time series each intensity value is independent of the previous and of the next. After all, the observation could have started or been stopped at any time, and each photon that is detected knows nothing about any other photon that we detected either before or after it. But to construct the periodogram each estimate of power for a particular frequency is calculated using all of the intensity measurements in the time series. The power at a given frequency can be thought of the measure of how well a sine curve of that frequency (inverse wavelength) matches the collection of intensities as a function of time. And so for each frequency, we can think of it as the mathematical version of drawing a sine curve over the data and measuring how closely it corresponds to the measurements.

All three scientists are interested in finding out if there is some kind of periodic signal in these data. The first scientist has a good implementation of a fast algorithm for computing the Fourier transform that they have been using throughout their very productive and prolific career analysing time series from X-ray emitting stars of different kinds, especially black holes. And therefore, this is what they do: the fast Fourier transform of the light curve, which looks like this:

fft

Fast Fourier Transform of binned time series shown in previous figure.

If there is a periodic component in the emission then it should appear as a single spike at the frequency corresponding to the period of the modulation in the number of photons detected as a function of time. If there isn’t, then we expect an average of 2 with a variance of 4, and therefore quite a bit of scatter. So, in just a few seconds of looking at this periodogram, the scientist concludes, precisely as we would as well, that there is no clear evidence of a periodic signal, but seemingly just statistical fluctuations from a Poisson process with a non-variable average intensity.

The second scientist has also been around for a while, but has mostly worked in gamma-ray astronomy where, until rather recently, the number of detected photons was so low that every single one had to be very carefully considered, and that, for this reason, nobody ever grouped photons together into binned light curves. Instead, they had been using the Rayleigh statistic to calculate the power based on the exact time of arrival of each photon in the data set.

Computing the Rayleigh power for each possible period in order to construct a complete periodogram is orders of magnitude slower than computing the fast Fourier transform, but because there were so few photons, with sometimes so much time between each one, that the Rayleigh statistic was really the only reasonable tool to use to search for a periodic modulation in the arrival times. Naturally, this is what they do with this data set, with these 5063 photon arrival times, testing a lot more frequencies than there are in the Fourier transform—frequencies which are between each independent Fourier frequency. They use the Rayleigh periodogram to compute the power for 20 additional frequencies (so 21 times more than the FFT). This is exactly what allows the second scientist to look in very fine detail at what is happening in the entire spectrum, and especially also in between the independent frequencies. The result is this:

r2_full

Rayleigh periodogram of event arrival times.

As you can see, we can’t see much from this periodogram. But because whenever they make a Rayleigh periodogram they always see a sharp rise in power at the lowest frequencies, they also always just ignore this, cutting it out of the view and rescaling the y-axis to see the rest of it better, like this:

r2_cut

Cropped and rescaled Rayleigh periodogram shown previous figure.

Lo and behold they discover that there is a peak that clearly stands out of the noise. Excluding the lowest frequency part, the peak stands out of the rest of the periodogram, which just looks like statistical fluctuations similar to those seen in the Fourier transform by the first scientist. The signal is very obvious, right there at a frequency of just over 4E-3 Hz. This is equivalent to a period of just under 250 seconds.

But is it okay to simply ignore part of the periodogram like that, and just focus on what looks interesting? Why is the signal so clear in the Rayleigh periodogram and absent from the Fourier transform? And why in the world does the Rayleigh periodogram have this sharp rise to huge powers at the lowest frequencies? Why doesn’t the Fourier transform have that? Can you really trust that the peak in the Rayleigh periodogram is indeed a signal and not just a fluke, a fluctuation similar to those that are seen at the lowest frequencies but that just happened to appear at a different spot?

As we saw earlier, a major difference between the Fourier transform and the Rayleigh periodogram is that the former is computed on a binned time series, which means it cannot take into account the time of arrival of each detected photon. And this is precisely what the latter does. But there is another major difference between them: the Fourier transform of a binned time series tests only independent frequencies. These are frequencies that correspond to periods that can fit an integer number of times in the time series.

The longest period that can be tested for in a time series lasting T=10000 s can obviously not be longer than 10000 s since we cannot test for periods longer than the duration of the observation. A period of ten thousand seconds is equivalent to a frequency of 1/T or 1E-4 Hz. After that, the time series can be tested for a period of 5000 s that fits two times in the time series, and this corresponds to a frequency of 2/T or 2E-4 Hz. Next, it can be tested for a period of 3333 s that fits exactly three times in the length of the observation and corresponds to a frequency of 3/T or 3E-4 Hz. And so on. So, basically, the only frequencies that can be tested are multiples of 1/T up to 1/2dt, where dt is the timescale of the binning, which in our case was 20 seconds, and hence a maximum frequency of 1/40 or 0.025 Hz.

The Rayleigh periodogram, because it is unbinned and uses the exact times of arrivals of the detected events, has no restrictions on the frequencies it can test and for which it can compute the power. That is, it has no restriction in testing how well a sine curve of that frequency matches the rate at which the events were detected. This is why the periodic signal is clearly detected by the Rayleigh periodogram and not seen in the Fourier transform.

In fact, looking even closer at the periodogram we find that the periodic signal peaks precisely at 247 seconds, corresponding to 40.5/T Hz, which happens to be exactly in between two independent frequencies, those of 40/T and 41/T Hz. This is why it literally slipped between the Fourier transform’s fingers. The Fourier transform in this case is like too coarse a comb, a comb with too much space between its teeth, through which a small knot in your hair can just slip and pass unnoticed. Here is what it looks like when we zoom in around the peak and compare the two periodograms:

fftAndR2

Zoom showing comparison between Fast Fourier Transform and Rayleigh periodogram.

The third scientist knows the Fourier transform as well as the Rayleigh periodogram, and understands where the differences between them come from. They have also understood why the Fourier transform does not have the huge rise in power at low frequencies—it only tests independent frequencies, while the Rayleigh periodogram does—it tests frequencies that are not independent and for which the powers are therefore correlated. They know that the reason why the Rayleigh periodogram does this is because it is computed as though it were calculating the power only at independent frequencies even if it isn’t. What needs to be done to avoid this—to correct for this effect—is to modify the Rayleigh statistic to account for the fact that we are testing frequencies that are not independent: frequencies (periods) that do not repeat an integer number of times within the span of the observation.

This is an analytical correction, something that can be calculated exactly. They do that and formulate the modification to the Rayleigh statistic with which they compute the periodogram of these data, the same exact 5063 photon arrival times. What they find is this:

modR2

Modified Rayleigh periodogram.

And to be absolutely sure that what they have computed is accurate, they compare the result with the Fourier transform. If the computation is correct, the powers at independent frequencies should match, and there should be no rise of power at low frequencies. Hence, they look closely at the low frequency part of the periodogram and find that they agree very well, exactly as they predicted, and exactly as they should. The comparison looks like this:

modR2_lowF

Comparison of Fast Fourier Transform and modified Rayleigh periodogram over entire frequency range.

The first scientist missed detecting the period in the data because they assumed that the Fourier transform was the best they could do in exploring the frequency space of these data, and that information of the independent frequencies was enough to fully characterise the signal when transforming it from intensity as a function of time to power as a function of frequency. The fact is, they most probably would never have known that there was a period in the data, because they would never have looked at these data again.

The second scientist detected the period in the data, but they were forced to arbitrarily cut out a part of the data, simply ignore it, and presume that the height of the peak was the correct power estimate for the periodic signal at 247 seconds. They did this because they had assumed that the Rayleigh statistic, which does not have any restrictions as to the frequencies it can test in a given data set, could be used to compute the power at any frequency, regardless of whether or not it was of an integer number of cycles within the observation duration.

The third scientist detected the periodic signal present in the 5063 arrival times of the detected X-ray photons, but unlike the second scientist, they did not exclude any portions of the data, and got an estimate of the power of the signal from which they could calculate precise and reliable quantities about the signal such as the probability of it having been a statistical fluctuation (1E-9), and the pulsed fraction of the signal, that is, the number of photons right on the sine curve with respect to the total (10%). Both of these, the second scientist would have gotten wrong. Not completely wrong, but wrong nonetheless.

How often does this happen in science? How often does it happen in medical trials? In trials testing a new critical procedure or a new drug? How often does this happen in industry? In testing of a new industrial machine or a new diagnostic technique?

How often does this happen to us in our own life? How often do we infer something, draw a conclusion, make a decision, and act based on assumptions hidden in our psyche so well that we are not even aware of them? Is there a way to overcome this problem?

My personal feeling is that this happens a lot. It is admittedly hard to measure and quantify, but I suppose with enough time and consideration that it could be done, at least for a handful of cases as the one presented here.

About overcoming this fundamental problem that does at first sight appear unsurmountable for the simple fact that we are biased by something we are not aware of being biased by, I think a solution is, by keeping this issue in mind, to not settle for something that can potentially, even hypothetically, be improved upon. In this way, we at least open up the possibility to go on finding more and more suitable methods, more and more accurate estimates, and more and more reliable answers to the questions we seek to answer.

Space, experience and perception

Darkness… cold… silence. Complete and perfect silence. In all directions: dark… cold… empty space. In the distance: the blue and vibrant glow of the Earth. Around it: dark, empty space. The Earth’s closest neighbour, Venus, is 40 million km away in the direction of the Sun. The second closest planet, Mars, is 70 million km away in the opposite direction. Our Sun, our life-giving Sun, is 150 million km away from us. The closest star, Proxima Centauri, is 4.37 light years or 40 000 billion km away. 40 000 billion km. Inconceivably far, and yet so close in comparison to the distance to the centre of our own home galaxy, from which it takes 26 000 years for light to reach us. This centre, this core, this heart around which everything revolves—every star, every dust grain, every molecule—and towards which everything falls without ever turning back, is a very unusual place indeed.

gb1244704496(image credit: NASA, Apollo 8 mission, taken by astronaut William A. Anders on December 24, 1968)

What is near, what is far? Is your house near or far from your office? Is India near or far from your city? Is the Moon near or far from the Earth? Is the Galactic centre near or far from the Solar system?

What is small, what is large? Is a virus small and a spider large? Is your hand small and your house large? Is your neighbourhood small and your country large? Is Pluto small and the Earth large? Is the Sun small or large?

What is vast and how vast is vast? Is our solar system vast? Is our Galaxy vast? Is our local group vast? Is the sky vast? Is the space of our lives vast? The space of seeing and hearing, the space of tasting and touching, the space of feeling, the space of our thoughts? Are these vast?

The Milky Way contains approximately two hundred billion stars. How many have solar systems? All these stars add up to a mass of about 100 billion solar masses. But we know from their orbits that the total mass of the Galaxy is around 1000 billion solar masses. This implies that all the stars, together with all the dust and molecular gas floating around make up approximately one tenth of the mass of the Galaxy. Where is the rest of it? What is the rest of it?

When a particle orbits a massive object, its velocity along the orbit depends on its distance from the central object: when it is closer it moves faster, and when it is farther it moves more slowly. If the orbit is circular, the orbital velocity is constant and depends only on the mass of the central object, and the distance from it. In the Solar system, where the planets move in circular orbits around the Sun, Mercury, the closest to it, moves at about 50 km/s, Venus moves at 35 km/s, Earth at 30 km/s, Mars at 25 km/s, and so on out to Uranus that moves at about 7 km/s and Neptune at 5.5 km/s. But all the stars in the Galaxy for which we have a measure of proper motion with respect to the centre, are moving at the same speed: they are all orbiting the Galactic centre with a velocity between 220 and 240 km/s. This does indeed seem odd. It is as if they were held in place by something, as if they were embedded in an invisible but massive, collision-less but gravity-binding cosmic gel. Even more surprising is that this binding cosmic gel, this Dark Matter (as it is called), accounts for 90% of the mass of the Galaxy, and therefore dictates the global dynamics of its contents. So, what appears as this all pervasive dark, cold, empty space is not so empty after all.

We move further and further away from our solar system, further and further away from the plane of the Galaxy. Its structure reveals itself as a gracefully shaped spiral with brightly illuminated arms, sprinkled with numberless point-like stars, and rotating majestically in a sea of subtly glowing red. This vast and expansive spiral extends over 100 000 light years. On average, 1 to 2 stars are born in our Galaxy every year, typically with about half the mass of the Sun, but sometimes much more massive, reaching 100 solar masses and more. They come to life in the depths of molecular clouds: the cloud collapses under its own gravity, and through this collapse dense cores appear and provide the ideal environment for star formation.

Winding inwards, the spiral arms merge with the Galaxy’s central stellar bar: millions of old, reddish stars that rotate coherently about the Galactic centre as an elongated structure 27 000 light years in length. The bar sweeps through space, sets in motion the gas and dust, and defines the molecular dynamics. From its edges to the very heart of the Galaxy, we think that the gas moves either in large elliptical orbits aligned with the bar, or on smaller orbits perpendicular to it, and contained within the larger ones. Turbulence in the flow makes the gas fall from the outer to the inner orbits, and then from those towards the central gravitational well.

The one central point around which everything turns is the location of the most massive object in the Galaxy. A single object with a mass equal to that of four millions Suns, it moulds space-time of the central region, and yet it is invisible. Everything we know about it has been deduced or inferred by observing its surrounding and immediate neighbourhood. That, at the very centre of our Galaxy, is a supermassive black hole, is conceptually ungraspable, and yet it is inescapable.

A black hole: a state of matter for which we hold no description, and where gravity has overcome all forces (first compressing all electrons into a single shell around the protons, then compressing the electrons and protons together into neutrons, and finally overcoming the strong force, and compressing the neutrons into something beyond what we can describe or imagine, a state of matter beyond our theories and ideas). It is indeed difficult to conceptualize. A supermassive black hole of millions, and in some galaxies, billions, of solar masses, is something entirely foreign. So far removed this is from what is conceivable to us, that it is most naturally perceived as science fiction. But we know that it is not fiction. We know that at the centre of our Galaxy there is a concentration of dark mass of four million Suns. We know precisely where its centre is—exactly at the dynamical centre of the central star cluster. We know its maximum spatial extent—it must be contained within the tightest and most eccentric orbit of any star orbiting around it. And we know that with respect to the Galaxy, it is perfectly still.

We know this from observations of the brightest stars around it, but also from the motion of molecular gas. In fact, it was close to thirty years ago that we found that the best explanation for the motion of the gas in the central part of the Galaxy was a mass distribution composed of an extended star cluster of about three million solar masses, and a compact source of about the same mass right at its centre. It was hypothesised that a supermassive black hole would appear as a very bright, compact radio source. A few years later, it was discovered.

The supermassive black hole at the heart of the Galaxy is known as Sagittarius A*.

A black hole is black: it does not emit any light. Newton published the Principia Mathematica in 1687 and since then we have had the notion of escape velocity: the speed at which an object must travel in order to overcome gravity and escape its hold. Interestingly, this velocity is independent of the mass of the escaping particle, and is determined by the mass to size ratio of the more massive object. It was pointed out long before Einstein published his Theories of Special and General Relativity in 1905 and 1916, respectively, that as this ratio increases by making the mass larger, the radius smaller or both, the escape velocity eventually surpasses the speed of light at the surface. The event horizon, the distance from a point-mass where light is unable to escape, the only place in the universe where light stands still, is known as the Schwarzschild radius: Rs=2GM/c2.

For an object of one solar mass, the Schwarzschild radius is 3 km. For a typical black hole of 10 solar masses it is 30 km. If you recall that the distance between us and the sun is 150 million km—a mere 8 light minutes, then can we ever dream of seeing this for even the closest stellar mass black hole in our Galaxy, V4641 Sagittarii (or SAX J1819.3-2525), about 1600 light years away? Not really. For Sgr A*, the Schwartzschild diameter is about 20 million km. Observing it from here, this size corresponds to an angular scale of 19 microarcseconds. (An arcminute is a sixtieth of a degree, an arcsecond is a sixtieth of an arcminute, and a microarcsecond is a millionth of an arcsecond.) Believe it or not, we can currently distinguish features on scales of 30 microarcseconds. This is done with a technique called Very Long Baseline Interferometry (or VLBI) that makes use of a network of radio telescopes all over the globe. VLBI has recently been used to observe Sgr A*, and revealed the intrinsic size of the emitting region at wavelengths of a few millimetres to be around 1 Astronomical Unit. This is as if 4 million solar masses were contained in the space between the Earth and the Sun. Within about 5 years, we will be able to distinguish the shadow of the black hole, the dark depression inside the event horizon, the well in the curvature of space-time produced by this massive object, against the background of the bright hot gas surrounding it.

I cheated a little with my connection between the escape velocity and the Schwartzschild radius. The escape velocity in classical physics is derived by equating the gravitational potential to the kinetic energy of an object with mass m. But light has no mass, and is therefore not subject to gravity, or is it? Although the concept of an astrophysical object whose escape velocity is greater than the speed of light has been around for quite some time, black holes are formally pure general relativistic objects, and it is only in the context of Einstein’s theory that we can treat them mathematically.

For Newton, as for most of us with perceptions based on our everyday experiences, there is space, and events occur at particular times within this space. Objects, either still or moving with respect to some given reference, are contained within the space, and do not have any kind of influence on it. Gravity is explained as a field that pervades all of space, acting everywhere simultaneously and instantaneously. Every mass, regardless of its magnitude, acts on every other mass everywhere and at once. Light is without mass and therefore does not feel gravity, moving freely at infinite speed, in infinite straight lines.

For Einstein, space, time, matter and energy, are so intimately interwoven that they cannot be treated as if they were separate from one another. The speed of light, accurately measured in 1885 by Michelson and Morley to be 300 000 km/s, is the ultimate velocity for everything in the universe: nothing—no information of any kind—can travel faster than light. Matter, radiation and energy are simply different facets of the same thing, which is not really a thing, and the manner in which they are distributed defines  the shape of space-time. It is the shape or curvature of space-time, not gravity, that defines the trajectories of particles and bodies. Consider the subtlety of this: the disposition of the total sum of energy—matter and radiation—shapes space-time and defines the rules of motion. But this energy that moves within this space-time follows its shape that it simultaneously defines. And since nothing can ever be still, and every particle is always moving with respect to something else, all space-times are always shifting and changing, continuously remodeled and reshaped by the matter and radiation moving within, and as them.

Everything is so interlaced, so intermingled. Space and time, light and matter, black holes and dust grains; the space between planets, the space between stars, the space between the spiral arms; the space of our world: delicate and tender, bright, green leaves, a single bird sitting on the bare branch of an old, withered tree in the morning sun, a poplar seed floating in the air, swaying gently up and down, and back and forth in the warm summer breeze; the space of our lives: the space of our thoughts and feelings, sometimes so vast and sometimes so small, the space of seeing and hearing, sometimes so bright and sometimes so dull, the space of tasting and touching, sometimes so sensitive and sometimes so numb; the space of the bodies and minds: the space all around the body, the space between our fingers and toes, the space inside our nostrils, in our mouth, in our throat, in our lungs and belly. Where do any one of these spaces begin and where do they end? Where can we find any border, any separation? What do we really know? What do we really understand? Everything is so interlaced and so intermingled.

We look up at the skies at night, and we see Orion the hunter with his bright belt of three stars in a line, his dagger pointing down, and his arms and legs outstretched in all four directions. How far is Orion? How far is each star drawing out the constellation on the sky? Are they close together or far from one another? What else is there that we do not see behind and around the stars? What about the Great Bear, the Big Dipper? What about the winged horse, Pegasus? What about Aquila the eagle, and the Cygnus the swan? How much more is there than we can see? What about a cloudless, clear blue sky of a sunny summer day, where are the stars? Are they behind the blue of the sky, are they hidden within it? What about your thoughts, are they inside your head? Are they behind your eyes? Is everything that we say just a way of speaking about things, just descriptions and conventions that we use to communicate? When we say “it is hot”, what do we mean? When we say “I am cold”, what do we mean? When we say “stars” and “planets”, “galaxies” and “universes”, what do we mean? Do we know what anything is? When we see blue, when we see green, what is that? Is it the pigment, the impinging light, the combination of the absorbed and reflected wavelengths on the surface? Where is this blue, this green? Is it on an object, on its surface, inside of it? Is it in the eyes, in the cones and rods of the eye? Is it in the brain? And every day, a hundred, a thousand times a day, when you say “I”, out loud or to yourself, what do you mean?

(This essay was commissioned and originally published here for the “beam me up” project.)

Does our life belong to us?

What makes your heart beat, what keeps it beating, is it you that does that? As an embryo deep in the warm muffled darkness of your mother’s womb, in the moment that the heart started beating for the very first time, in the moment it made its first beat, did you have anything to do with it, did your mother, did you or her have any say in this? Right now, as you are sitting here reading these words, can you choose to continue or to stop beating the heart? When you walk up a set of stairs, go for a run or bike ride, lift a heavy deadlift or push a heavy benchpress and the heart beats stronger and faster, do you have anything to do with it, can you choose to have it beating any other way than it does? What about when you lie down in your bed at night, lying calmly in the quiet darkened room, feeling the rhythmic pulsing of the heart beats, do you have anything to do with it? And when you fall asleep and lose consciousness of all bodily sensations and the heart keeps beating, adjusting its pace based on your dreamworld activity, what you are unconsciously thinking, feeling, doing, do you have anything to do with that?

Human-Heart-Organ-Faust-heart-symbolises

And what about the kidneys, do you control the kidneys: the rate at which they filter your blood, the amount of water and sodium they retain or excrete, the amount of uric acid and creatinine they recycle or discard, the amount of renin or angiotensin they secrete into the bloodstream? And the pancreas, do you control that: the amount of insulin that it produces and the speed at which it releases it in the blood, the precise time at which and concentration of the water-bicarbonate solution it manufactures and secretes into the small intestines when the acidic chyme is moved into it from the stomach, the amount and kinds of enzymes it makes and sends into the intestines during digestion? Do you control any of that, do you have any say in what these organs and every other organ of the body does, how they do it, and when they do it?

In the moment that your hand takes hold of a glass of water or a cup of tea, and that the feeling of its surface and its cool or warm temperature are felt by the palm, the fingers and fingertips, do you choose to feel, do you have anything to do with that feeling, those sensations that arise in this holding up of the glass as you bring it to your lips? And when you take a sip and feel the water in the mouth, on the tongue, on the inner cheeks, on the roof and in the the back of the mouth behind the tongue, in the throat and down its length as you swallow, do you choose to feel this, all these nerve endings firing, discharging electrical pulses that travel at fantastic speeds through the mesh of nerves throughout the body back and forth to and from the brain and its neurones, do you have anything to do with this?

When you feel hunger, thirst, the need to go to the bathroom, when you feel heat and cold, when the eyes close of tiredness, and when these and the multitude of other functions of the body manifest themselves through the countless bodily processes that take place in their own time, on their own accord, do you have anything to do with it, do you have the ability to choose or decide anything about how they are manifested? And when, one day, a last and final breath is exhaled in a slippery whisper past a small opening between the dry and thin lips of your mouth, and the heart stops beating, and the blood stops coursing through the veins and arteries, and the eyes stop blinking, and all twitching and pulsing of the body and its organs cease and give way to stillness, do you have anything to do with this, could you, in that moment, choose any other outcome, any other way in which these processes will play themselves out, on the order or timing of the sequence, on anything at all? Of course not.

The recognition of this basic fact—the fact that this body is not our body, and the life it is infused with is not our life—is both profound and obvious. Is profound because it puts into question the deepest foundations upon which we have built the worldview we hold, everything we believe about ourselves, about others, about living beings and inanimate things, and about the relationships between all of these aspects of the world as they are conceptualised and objectified in our minds. It is obvious because if we stop for a moment and ask ourselves the questions we posed above, or any number of questions of a similar nature, it is very difficult to sincerely answer any of them in any other way: the answer is obvious and it is always ‘no’. Your body is not yours, and your life is not yours. They are not yours, and they are not anyone else’s either, because neither can be claimed and neither can be owned.

Why is it, then, that we believe this body and this body’s life to be ours? Can we not slit our wrists, cut open our jugular or femoral arteries, drive a knife through the heart, shoot a bullet through the brain? Doesn’t this mean that they are ours, that they belong to us, that they are ours to do with as we want? And we can do any of these things to someone else as well. Does this mean that their body or life belong to us? We can cut off a finger or an arm, toe or foot, ear or nose, but does this mean that we own these parts of the body, that they are our possessions to manipulate, modify, mutilate or discard as we please? In a way it does: we actually can do with them as we wish, as long as there is nobody to stop us from doing it. But at the same time, it is obvious that being able to and actually doing such things to ourselves and others betrays only that we are able to so thoroughly fool ourselves in believing that we do own our body and life that it gives us the capacity to enact such things. The reason we believe this body and this body’s life belong to us is nothing more than this: a worldview made up of and continuously distorted by unexamined assumptions, unquestioned beliefs, unrecognised objectifications, rationalisations and self-justifications all based on and fuelling further misunderstandings about the nature of this body and the nature of this mind, the nature of self and the nature of other, and the nature of this life and of Life itself.

What about your thoughts and feelings. Do you own them? Can you claim them as yours? For aren’t our thoughts and feelings the most intimate manifestations of our personalities, of our characters, of ourselves? But what are thoughts, what are feelings? How do they arise, where do they come from, where do they go to? Do they exist on their own? What can we know about these thoughts and feelings we experience? We can see them, know them, feel them, but can we choose whether or not they arise and whether or not they are seen and felt?

You’re at the table eating with your family and the phone rings. You pick it up and your brother just says “papa is dead”. The rush of heat sweeps up the body, from the legs up to the face and forehead. The shivers that run up the back and down the arms. The tears well up and fill the eyes. There is tightness in the throat and in the belly. There is pressure on the chest, as if being squeezed from the outside. There is a trembling in the hands, a weakness in the thighs, at the knees. Do you have any influence on the sequence of biochemically triggered events initiated by those simple words spoken over the phone line that set on its way a cascade of hormone-driven reactions vividly felt in a range of different emotional and sensorial responses throughout the bodymind? Can we, at any moment during this short intense experience, choose to not feel what is being felt?

Naturally, every person would have a different range of feelings and sensations that would depend on what their father was to them. Some could be indifferent and unmoved. Some could even be relieved and happy at this news of their father’s passing. But the point here is that no matter what reactions, feelings, thoughts and overall bodily responses, we do not choose, we do not decide what happens. We are subject to it and are aware of it because it is felt with and as the bodymind, from head to toe, from the knees to the throat, from the belly to the chest to the shoulders to the neck. What we can choose is what to do with this information that is presented to us in the stream of experiences that make up this moment of experiencing: we can choose what we say and what we do, but we cannot choose to feel or not feel, how and what thoughts and feelings will come up, and how any and all of these will both express themselves and affect the biochemistry of this bodymind. In this, we have no say.

You are sitting on your own reading a book. It is a quiet, early Sunday morning. There is no traffic, no activity, and everyone in your place and in the building is still sleeping. Morning sun rays are streaming through the small red leaves of the Japanese maple on the terrace outside, falling onto the cream coloured stone tiles and white walls in streaks. You are calm and comfortable. Unrelated to what you’re reading, in a flash, you see yourself in your mind’s eye standing before your colleagues to talk about your work at the meeting scheduled to take place on Friday next week. This appears out of nowhere and without your noticing immediately takes hold of your attention. In this instant, you feel the heart speed up, the belly tighten, the heat rise to the head, the tingling in the cheeks, and the breathing move up into the upper chest. You look at your dog, he looks back at you with his beautiful brown eyes with a docile, loving expression of trust and admiration, lying on his side in his dog bed he wags his tail a little, the heart slows down, the tightness and the heat dissipate, the breathing slides back down into the belly, the tension in the eyes, eyebrows and forehead is released. Did you have anything to do with all that just happened? Could you have willed it to happen or not to happen? The image popped up in your mind and the brain responded instantaneously by the release of the appropriate stress hormones that triggered the cascade of biochemical reactions that were felt as those physical sensations you felt throughout the body. A moment later, a change in the configuration of attention set in motion the change of the biochemical environment that was felt as the passing, the dissolving, of the previous state of nervousness and anxiety, back to a more relaxed state, in accord with the current circumstances of you reclining on the couch, with the book in your hand, on this calm Sunday morning,in a room bathed by a gentle morning sunshine, in the company of your loving dog.

We do not choose or control the thoughts and images that come and go, that in an instant appear within the field of attention, without reason, on their own time, on their own accord. We do not choose or control the chain reaction of hormone-regulated biochemical changes and or their physiological effects that we feel as emotions and sensations. They just happen. What we can choose is what we do with the information about the process of experiencing that is manifested in the bodymind in the moment that it is felt. We can allow the process to take its course and pass on, allow it to rise, dwell and decay on its own. We can also feed into it and propagate it by giving it more fuel, more thoughts and feelings. We can stir the process in another direction by feeding it a particular kind of fuel, a particular flavour of thoughts and feelings, words and images. This, we can control to a greater or lesser extent. But it is perfectly obvious that we do not own our thoughts and feelings. We do not own them in the same way that we do not own our organs, our body and our life.

What about everything else: every other thing we see and encounter; touch and feel; eat or drink; wear, wear out, and throw away? Can we be said to own any of those things?

You are walking around a city you don’t know, up and down little cobblestone streets, up and down long flights of stone stairs worn smooth from the millions of passersby over the ages, through parks, and down long, wide, busy, bustling and traffic-jammed avenues. You get thirsty, stop in a small side street corner store, and buy a bottle of water. You open it and drink. The refreshing sensation of cool water in the mouth and on the tongue, the cool freshness moving along down the throat. There’s also the sensation of the thin but hard crackling plastic bottle in the hand, on the fingers and the palm, the weight of it you feel in the contracted biceps of the arm with which the bottle is held and brought to the mouth for drinking. Where did this water come from, where did this bottle come from? From a mineral spring in a mountain somewhere, from a plastic bottle factory on the banks of a polluted river in the outskirts of a large city’s industrial zone somewhere? And before there was water in that mineral mountain spring, where was the water, where did it come from in the first place? And the bottle’s hydrocarbons, where did they come from in the first place, how were they formed, from what were they formed? And the mountain, how long has it been there, what was there before, how and when did the mountain itself come to be? And the petroleum field where were extracted the hydrocarbons from which the plastic was made, how long did it take to make and form? In such a context, is it even necessary to reflect on the absurdity of believing for even an instant that this water that made its way to the surface of the earth by the gravitational capture or close fly-bys of melting comments from the outer solar system some 4 billion years ago can belong to someone, to anyone? Or the absurdity of believing that the plastic bottle made of refined and then extensively processed hydrocarbons that were formed over hundreds of millions of years from generation upon generation of forests covering entire continents, fallen and decomposed organic matter transformed and liquefied under the enormous pressures of the layers upon layers of an ever thickening crust of organic and mineral sentiments from plants, brought by wind and rain, streams, rivers and oceans can be owned? Can anybody when faced with this question posed in these terms not immediately see the absurdity of claiming some kind, any kind, of ownership of this water or of this seemingly insignificant transparent plastic bottle?

So you drink the water, it goes in the belly, then in the intestines, then in the blood, then through the kidneys, then in the bladder, and then in the urine that you pee out into the toilet. Is this urine yours? When it trickles from the kidneys into the bladder, when it makes its way through the urethra, when it comes out, when it accumulates in the toilet, when you flush the toilet? When do you own that urine that the kidneys filtering the blood have concentrated and sent to the bladder, and which is now coursing in sewers, mixed with that of hundreds, thousands, millions of other people in the city and region where you live? And when eventually, after processing, filtration, decontamination, this water makes its way back to the parks, to the grass, the bushes, the trees that grow all around in your neighbourhood, absorbing light, water and minerals, growing fibre and producing oxygen while taking up carbon dioxide from the air, is there any point at any time along this entire cycle when anyone could possibly claim ownership of any part of any of this?

You put the pressure cooker on the stovetop at medium-high heat, and put a few tablespoons of coconut oil in it. You dice an onion and put it into the heating oil, add salt and curry powder, stir it, and leave it sizzling. You take out a cauliflower from the fridge, wash it, and cut it up in pieces, put it in the pot, stir it and leave it sizzling for a few minutes. You add three quarters of a litre of water, a teaspoon of vegetable broth concentrate, and close the pot to let it simmer for half an hour or so. During this time you prepare a salad: fresh mixed baby greens, sunflower and alfalfa sprouts, an english cucumber chopped in little pieces, roasted sunflower seeds and almonds. You put on some extra virgin olive oil, unrefined salt and fresh milled black pepper. You blend the cauliflower soup, add a can of coconut milk and blend again until it is perfectly creamy and smooth. You serve the soup and salad and sit down to share them with your family. Everyone loves the delicious soup and excellent salad, and now the bowls and plates are empty.

When did you or anyone else begin to own the food that was just eaten? Was it upon putting it in the mouth or upon swallowing it? Was it when it was chopped in pieces or when it was placed in the pot or salad bowl? Was it when you paid the cashier at the store, placed it in your canvas shopping bag, and drove home with your groceries? What about the store: did the store begin owning the food when the farmer brought it there, was paid for it and went back to their farm? And the farmer, did they ever own the lettuce, the cucumbers, the cauliflower, the onions? Was it when the seeds were planted, was it when they sprouted, was it when they began growing or when they were fully mature and ready for the picking? What did these vegetables grow from: the soil, the minerals, the water, the sunlight, the carbon dioxide in the air, do these belong to anyone, do they belong to the farmer, to the owner of the land? Is it because the farmer tended the garden and fields where these things grew that they have at one point belonged to him? Is it because the store paid the farmer for them that they then belonged to the store owner? Is it because we bought them from the store that their ownership was transferred to us? Is it because we prepared and ate these things that they now for sure belong to us? And when they are digested and processed by the stomach and the rest of the digestive system, and when their byproducts are excreted as stools in the toilet and flushed out of sight and out of smell, to whom will they belong at that point?

And what about your shoes, your glasses, your underwear, your jeans and shirts, your sweaters and jackets, those you are wearing now, those you wore last year and the year before that, those you wore 10, 20, 30 years ago, as a teenager, as a child and as a toddler, as an infant and as a newborn, were those clothes ever yours, are these clothes ever yours? The fabrics from which they are made, the cotton that grew in the fields, the wool that grew on the sheep, the polyester that was manufactured, like that plastic bottle, from petroleum hydrocarbons, the leather from the cow’s hide, and the rubber of your shoes, to whom do they belong? To the farmers? To the manufacturers? To the stores? To you? And from what point, and until what point?

You are driving to the office on Monday morning. You stop at a street corner and wait for the traffic lights to turn green. They do and you pull out into the intersection. A fraction of a second later, an 18 wheeler transport truck hits your car from the driver side and you’re instantly killed. To whom does the cauliflower, cucumber and lettuce now belong? To whom do the shoes and jackets sitting in your closet at home belong now? To whom do the broken glasses on your face, the bloodstained clothes on your body, the shoes on your feet belong now? And the thoughts and feelings now silenced? And the body: the heart and brain; the eyes, ears nose and lips; the hair and nails; the hands and fingers; the feet and legs; the arms, shoulders, back and spine; the stomach, the kidneys, the pancreas; the bladder and the urine; the intestines and the stools; the blood; the life. To whom do all these thing belong now? To whom do this life now gone belong in this moment, in this place, in this broken car, on this intersection, somewhere between your apartment and your office?

Everything is given to us, everything is borrowed, used, transformed, recycled, given again, borrowed again, used again, transformed and recycled again. Again, and again, and again. Thoughts and feelings arise in their own time, on their own accord, they are seen, felt, reacted to and responded to, but cannot ever be claimed or owned, and they cannot ever define who and what we are. The mystery of life—microbial life, plant life, animal life, your life—is the most profound mystery in the universe. We have to recognise this, accept this, embrace and cherish this. Not ignore or gloss over it to avoid the inconvenience of having to deal with it. Why choose to pretend this is not so and live a lie that can inevitably only be partial because somehow we know that we are pretending and lying to ourselves and everyone else about ourselves and this world. There can be no honesty, no sincerity, no genuineness without the recognition of this truth and the embracing of this mystery of Life into our being, into this manifestation of it, into this expression of this Life as our life, this Life that lives as this bodymind and as all bodyminds in all directions and throughout all times.

Remarks on the evolution of species: gradual or sudden?

This is not a raging debate. If it were, we would have heard about it, and that’s definitely not the case. But it was raging 150 years ago, when was published for the first time Darwin’s book On the Origin of Species. Do species evolve into different varieties and then into different species slowly, little by little over millennia? Or do they burst into life in great varieties together at the same time? Is the evolution of species gradual or sudden?

Admittedly, the debate wasn’t raging in pubs and street corners. It was between scholars with an interest in this question: naturalists, palaeontologists, archeologists. Today, the views of people in these fields on this and related questions are not so polarised: we have gathered a lot of data and acquired a greater understanding of the process of evolution as a whole—geological, biological and paleontological—over the last century and a half. But here is the thing that struck me last week when I got to Darwin’s discussion of this point, well into the second half of his book.

Several years ago, I read Stephen Jay Gould’s book Wonderful Life. I was amazed. This was surely in part because it was the first time I was reading a book of this kind, but it was also surely in part because it was simply fascinating to me to learn all these things I had never heard about anywhere else. Gould tells the story of the Burgess Shale in the Rocky Mountains of British Columbia discovered by the naturalist Walcott in 1909 and excavated by him and his wife over many years, summer after summer, slowly and painstakingly, during the following few decades. The distinct impression with which I was left was that Gould was arguing in support of a theory of evolution where widely different species appear in a short period of time (on evolutionary timescales), and then disappear or evolve more or less quickly depending on their particular abilities to adapt the the conditions under which they compete with others in their struggle for life.

This position and line of argument necessarily implied that there was a debate about the question of how species have evolved, and in addition, judging from the tone and general style of his argumentation, that he was himself campaigning to convince people of this, being somewhat isolated in this view. As a consequence, I was left with the impression that this was a modern debate, ongoing between Gould and others in the field from which (I only later found out) he was somewhat estranged. From Gould’s book, I was left thinking this view of a sudden evolution of species and varieties versus a slow and gradual process of accumulating genetic variations favourable for survival under changing conditions through the process of natural selection had been formulated recently. What a surprise it was to see Darwin himself addressing this question, countering well-formulated arguments and critiques of several eminent scholars he mentioned who favoured the hypothesis of a sudden rather than gradual evolution more than 150 years ago already!

There is no contradiction, though. The reason for this misinterpretation on my part is due to my own ignorance of the subject. Had I read a little more I surely would have understood that the debate was an old one. That Gould’s position, his line of argument, and the debate within which he was engaged during his life (1941-2002) as a scholar had a longer history. That the debate had been evolving slowly over the last two centuries, and that it has not suddenly appeared into the arena of hot topics in palaeontology, and that it must have surely have been most vigorous within Darwin’s own lifetime after the appearance of On the Origin of Species.

What the Burgess Shale revealed was out of this world.  But this was not understood for a long time: not until the latter part of the twentieth century. Walcott and his wife spent decades excavating, collecting, cleaning and classifying the specimens they would find doing this work on their own, summer after summer (this is how they spent their summer holidays). There were also generally very few people interested and  motivated enough to do this. In the end, it was their discovery, after all, and it was natural for them to work on it and for others to let them do it. The passing of a few decades, world war, major societal changes, and the Burgess Shale was largely forgotten. And besides, everyone wants to discover, to be the discoverer; nobody wants to rummage around someone else’s leftovers looking for something interesting they might have missed by sifting through decades of rubble: finding a gem in piles of rubbish is never very likely. But the gem was not to be found in the rubble; it was to be found in the re-examination of the fossils!

If you want to do your own discovery of the interesting history and intriguing story of the Burgess Shale and its weird animals, you should read Gould’s Wonderful Life. What I want to share with you here is that the fossils in these 530 million year old sedimentary layers were 1) exceptionally well preserved, 2) remarkably concentrated and large in numbers, 3) astonishingly wide-ranging in their variety of radically different body plans, major and minor structures, and physical appearance, and 4) all lived together, simultaneously and side by side, in the warm shallows of the primordial seas of the pre-cambrian. The ensemble of organisms in the Burgess Shale is one of the best examples of the pre-cambrian explosion: a very short period in our Earth’s history that saw, in several different areas of the world, an explosion of strange and wonderful creatures, a small number of which survived to become the ancestors to all currently living animals, including ourselves, of course.

In particular, it was found in the Burgess Shale one little creature, seemingly insignificant in comparison to the so many other larger, stronger and fiercer looking creatures, that is likely the first common ancestor to all vertebrates. That’s pretty huge if you consider that you will likely be hard pressed to think of more than a few animals that are not vertebrates. What this little creature looks like is nothing more than a tiny swimming spine covered in skin, with a little head and mouth at one end and bum hole at the other, with a thin digestive tube going along the spine from mouth to bum hole.

It is today plainly obvious that Darwin was correct in practically every conclusion is drew and explained in his writings, following a lifetime of observations, experiments, readings and lengthy considerations on the nature of evolution and on life itself. It is also clearly obvious that he was exceptionally gifted in his observational, scientific and intellectual skills, as well as remarkable forward-thinking and greatly ahead of his times. At the same time, it is obvious today that what the Burgess Shales tells us in a manner that makes it undeniable is that in the course of the history of life on this planet, explosions of species with widely different body architectures, sense organs and life systems have occurred. These species have coexisted for a time but then most have disappeared and left only a few of them as the progenitors for future generations of species and varieties within species.

We could say that Nature sometime plays a game of chance by producing as many different configurations and structures of living systems just so to maximise the probability that at least one of them will survive, evolve and procreate. Then again, we could also say that when the conditions are good, whatever is possible happens, more or less frequently depending on the requirements for this thing to happen, and therefore, without much restrictions on the conditions of life, a huge variety of organisms will appear in a relatively short span of time, that will look to us from the perspective we have today on the length of geological timescales like a wild and uncontrolled explosion of life.

Independently of interpretations or explanations, it is not debatable that new species sometimes appear very suddenly, and that sometimes they evolve from an ancestor very slowly over millennia. It is not debatable because both are seen in the biological and geological record, providing more than enough evidence to come to this conclusion. So what is there to debate? Why is there a debate? We can understand why there would have been one 150 years ago, but today? Maybe because the importance of each of these two different ways of evolution is difficult to asses. Maybe because some scholars grant to one a much greater importance while others disagree. Whatever the case is, it looks like I’ll have to keep reading and mulling over this matter to eventually come up with an explanation. And you, do you have any thoughts you’d like to share about this?

What are we?

Why is it that every time you think something, and by that I mean every time you talk to yourself quietly inside your head, each time you start telling yourself something, it starts with I?

I’m hungry. I need to piss. I’m tired. I’m so late. I’m sick of this. I don’t feel like it. I love it. I’m going to get dressed now. I need to go poo. I’m going to do this later. I don’t want to go. I’m thirsty. I need to eat right now. I’m going to work. I’m going home. I hate this. I really want this. Why can’t I have this? Why is my life so hard?

Why do we do it? This run-on monologue about ourselves with ourselves, continuously commenting on everything we see, everything we do, all day, every day, always talking to ourselves about ourselves. And why in the world do we take all of it so seriously? All of these ridiculous, fabricated, distorted stories, impressions and judgments about everything and everyone; all these self-justifications we use to convince ourselves that we are totally entitled to be upset, to be angry, to be furious, to be sad, to be feeling sorry for ourselves, to be feeling that we have been wronged or that we deserve so much more than this: justifications, explanations, rationalisations for absolutely everything we want to believe, on and on, day after day, our whole life?

Fucking hell! Is this not completely insane?

What is this? Where does it come from? What it is, is an innate tendency developed to the extreme but unrecognised and therefore invisible to us: completely outside the scope of what we ever allow ourselves to see or to believe. It is a tendency that pushes us to define ourselves by what we do, where we come from, who our parents were, where they came from. To define ourselves by what we think, what we have studied, what we have learned, what we know, what we think we know, what we have read, what we believe and what we want to believe. To define ourselves by what we feel, what we want or would like to feel, what we have felt at various times, what we like and what we dislike, what we think we should like and dislike, what our friends like and dislike, and what our friends think we should like and dislike. To define ourselves by the clothes we wear, by the shoes we have, by the way we cut and style our hair, by what we think people think of us when they see us, by what we would like people to think when they see us. To define ourselves by how many people clicked the Like button on that shot of ourselves on the beach, or on that new profile picture we just put up.

Do we have to be so unboundedly self-absorbed, self-concerned, self-obsessed? Is this just how we are? Is there really such a thing as The Selfish Gene? Maybe there is. But maybe it is simply that we have become so masterful in ways to stimulating its expression that no alternative course is anywhere or at anytime apparent or even imaginable?

What are we? Are we beings of light? Are we part of a unified radiantly beautiful universal soul that has always existed and always will for eternity? Are we creatures of God, created in their image and carrying in us part of them in the form of a stainlessly pure and eternal soul? Could it be, just maybe, that all of these and the multitude of variations on these are just more stories that we tell ourselves, like all the other stories about everything else we know and think we know. More fabrications, more justifications, more rationalisation for this or that reason, for this or that purpose, all of this more lies, day after day, century after century, millennia after millennia?

What we are is this: upright walking animals from a single species most closely related to primates, with extremely well developed language skills and technologies of all kinds, that have evolved as preys for most of our history, have now come to dominate the planet in every way as The predator, but retained our deep psychological instincts as prey, and have, since the very beginnings of oral and pictorial expression, told ourselves and those around us stories to explain what we saw in the world, hardly anything of which we understood, and over the centuries and millennia developed more and more sophisticated ways to occupy, amuse, entertain, delude and lie to ourselves and others about what we are, what we think we are, what we fear we are, and what we would like to be.

Look around. Look at what we have done with this amazing planet, what we have done with its rivers and oceans, its mountains and plains, its air and atmosphere. Look at what we have done with its plants and animals, what we have done with the stuff we eat, the stuff we drink, the stuff we use to put on the skin, in the hair, in the dishwasher and washing machine, on the grass, in the gardens and in the parks. Look at the world that is manifest through Facebook or Twitter and its oceans of selfies, technically limitless and yet full to overflowing in appearance. What does this tell us about where things are going? How long can we go on in this way? When will we get to the end of the rope?

Do we have to continue in this way until we reach the end of the rope? Do we have to continue feeding into this tendency to self-absorbed, self-obsessed selfishness? Do we have to continue defining ourselves by all of these things around us, all this stuff, all these opinions, convictions, beliefs, likes and dislikes? Do we have to continue talking to ourselves about ourselves and others from the moment we wake to the moment we fade into sleep? We don’t. We can stop this right now. And we should. We have to. Don’t you think?

How do you start? It’s very simple. First: shut up and stop talking to yourself; whatever it is, just shut up, listen, and don’t comment. Second: stop taking yourself so fucking seriously. Stop thinking that what you want, what you like, what you don’t like, are all so important. They are not. You are not. You’re just like everyone else. Like 7 billion other people. Third: feel the breath, each breath, moving in and out of the body, and pay very close attention to the details of the sensations of the body in every moment and in everything that you do. Just this will transform you entirely. Guaranteed.

Reflections on what it is to be a scientist

What is it to be a scientist? What do scientists mean and understand by the word “scientist”? What do non-scientists mean and understand by that same word “scientist”? Are non-scientists really not scientists? And are scientists really scientists?

You get up in the morning, go pee, wash your hands and face with cold water, brush your teeth, and go have a good drink of water. You have a shower, get dressed, maybe have some coffee or tea, maybe breakfast, and then go to work. You get to the office and you start working on whatever it is that you were doing the day before, or start working on something new, but typically of a very similar nature as to that of what you were doing yesterday, the day before, the day before that, and for possibly years and decades.

This “work” that you do can be anything: preparing your next class of history or economics, literature or philosophy, geography, biology, chemistry, physics or math, to be presented later that day or next week to your grade 6, grade 9 or graduating students; it can be preparing for your next meeting in which you are presenting to potential investors your revolutionary idea for a project that will be so lucrative it will make Facebook look amateurish; it can be looking through tables of numbers in accounting spreadsheets to track expenditures and sales to make sure that your business is doing good and can continue to function as it has for years in this unpredictable market of consumers regulated by their likes and dislikes, their moods and fashions, their hopes or fears about the evolution of the national economy, and on and on; it can be to set up your cash, making sure you have enough of all the different types of coins and bills, and then starting, from the moment the store doors open, to ring things in from the first customer that lines up at your cash to buy their groceries for the day or the week, continuing this routine of welcoming and greeting them politely, passing all their items, obviously withholding any judgement on their person for buying those things, helping them bag their stuff and wishing them a pleasant day, over and over again from morning to night.

Of course, it can also be to sit down at your desk with your steaming cup of green tea, open a book, and start to read about the history of the second world war from the Chinese or Japanese perspective, about the comparative evolution of our species following the last ice age in the Fertile Crescent and North America, about writing style and how to craft the perfect sentence, about the relationship of butterfly species and birds on the different continents and climates, about the visual display of quantitative information, about political stability and civil unrest in developing countries in the latter half of the twentieth century; or it could be Plato’s dialogues, Galileo’s Messenger from the Stars, Newton’s Principia Mathematica, Darwin’s On the Origin of Species, Kant’s Critique of Pure Reason, Wittgenstein’s Philosophical Investigations, Popper’s Logic of Scientific Discovery, Savage’s Foundations of Statistics, Jaynes’s Probability Theory — the Logic of Science, or anything else from the countless works available for us to read, available for anyone to read at any time given their willingness and effort to read it.

Does what we do define who or what we are? No, it doesn’t. Does what we do tend to define the way we consider and perceive the world? Yes, it does. Does what we read, have read, think about define who or what we are? No, it doesn’t. Does what we read, have read, think about tend to define the way we consider and perceive the world? Yes, it does.

The persona of ‘the scientist’ dates back several centuries, if not millennia, all the way to ancient Egypt, Persia and Greece, where those who wondered about the functioning of the physical world, measured positions and motions of celestial objects, and worked out ways of both keeping track of things as well as calculating and estimating quantities related to physical phenomena, always stood out from the population, and had very privileged positions in society as holders of secret knowledge and deeper truths about the inner workings of the physical world. In many ways, this is still true today, albeit much less so, because scientists are enormously more numerous than they would have been several thousand or even a as little as a hundred years ago, when they were really extremely rare.

But what do twentieth century philosophers like Wittgenstein, Popper and Bertrand Russell mean when they use the word scientist, when they discuss what it means to speak the language of a scientist, to think like a scientist, to perceive the world like a scientist? Do they talk about those famous few that have marked the history of science but that are also remembered for it? Scientists like Copernicus, Galileo and Tycho Brahe, Rene Descartes, Blaise Pascal and Isaac Newton, Jacob Bernoulli, Leonard Euler and Karl Friedrich Gauss, Pierre Simon Laplace and James Clerk Maxwell, Karl Pearson and Ronald Fisher, Niels Bohr, Max Planck and Erwin Schrodinger, Bernhard Riemann, Hermann Minkowski and David Hilbert, Hendrik Lorentz and Albert Einstein, Roger Penrose and Stephen Hawking, Enrico Fermi and Richard Feynman, and so many more uniquely gifted people whose work and discoveries we have studied and admired, often marvelled at as senior university students, but whose persons, personal traits, tendencies beliefs, social behaviours and familial relationships most of us know nothing about. Is this important or is it irrelevant?

einsteinWritingOnBlackboard

The scientist’s persona is defined by a complex mixture of ideas, beliefs, prejudices and other intellectual constructs rooted in a collective consciousness in which everything is distorted. We add to this the powerful attraction we tend to have to myths and tales, and our love for making important figures of the past larger than life, greater than great, more singular, more unique, more unusual, more special than anyone alive that we can actually see, encounter, speak to and interact with in person, even if hypothetically. Why all of this seems to be the way it is, no matter which human collective we consider, indeed is a good question whose answer could probably be found by digging into evolution and anthropological, into everything we can find out about our human ancestry, hoping to help elucidate deeply rooted psychological tendencies and behaviours we, as members of this race of homo sapiens, all share together.

But regardless of the actual details and the level of sophistication or refinement of what great scientists and mathematicians, great philosophers and thinkers, great historians and sociologists, or anybody else may have meant when speaking and referring to the notion of ‘the scientist’, it cannot have been and still cannot be anything other than an agglomeration of complex entangled intellectual, cultural, emotional and psychological constructs. Therefore, the unavoidable conclusion is that philosophers speaking of ‘the scientist’ are speaking of what they think and what they believe this is or should be. They are speaking of that complex mental construct they have developed and formulated in some way, undoubtedly to a level that satisfies their own requirements of intellectual and philosophical rigour, but that, in the end, bears little connection to the practical reality of what it is to be a scientist.

An innumerable number of interesting and useful questions can be posed, and an equally innumerable number of valid and different answers can be put forth in regards to this question of what it is to be a scientist. Does this mean it is not possible to agree on what is meant by it? Or does it mean that this is, in fact, quite hard to do?

Are we a scientist if we have a Bachelor’s degree in a scientific discipline? Anyone who does, knows that by the end of a Bachelor’s degree, what we know is that we have barely touched upon the rudiments of the discipline we have spent three or four years studying up to this point. And for most, it is almost embarrassing to be presented or even considered to be a scientist after graduating in physics or chemistry or biology or whatever other scientific field of study. So, the answer is definitely no.

Are we a scientist once we have spent another two or more years studying and working hard on much more advanced subjects towards a Master’s degree? Here again, doing this only serves to show us how little we know about the process of doing research and about the actual scientific foundations of the research we are participating in under the supervision and guidance of our thesis adviser. This is especially obvious if we are surrounded by or in contact with other graduate students working on their PhD with several more years of experience, and to whom we continuously turn for help and advice, these senior student who appear to us so knowledgeable and so wise from our perspective. So, are we a scientist once we have finished and defended our Master’s thesis, something that may have seemed to us a remarkable and maybe even gruelling accomplishment, but which to any doctoral student who has been through it is now seen for what it actually is: a baby thesis, a warm up for the real thing, for the real thesis that is the doctoral thesis.

Are we a scientist when we finish the course work for our PhD? When we finish the research project we chose or were encouraged to tackle? When we finish writing our doctoral thesis after three, four, five or more years of studying, reading countless papers and books, trying hard to understand things we don’t understand over and over again to eventually understand some of them, rarely completely and usually only superficially, but without knowing it, and only later, upon uncovering yet another level of understanding, realising it? When we defend the thesis and have this moment of great personal satisfaction and maybe even pride?

Of course not! We feel like we are just now allowed to enter the lowest ranks of research workers like our supervisors and their colleagues, those who have been doing research for decades, many sometimes started before we were even born, and we are a new kid on the block who mostly knows things that everyone else in the field knows, with possibly a few tiny bits that we might know a little better than some, but usually only in our skewed perspective and restricted exposure both of which are the result of isolating ourselves in order to complete the work that we have either set for ourselves or that has been set before us.

So, are we a scientist when we have that PhD that we can when we choose to place before or after our name? No, we are not. At least not relatively speaking. Although when we go out in the world and exchange with ‘regular folks’, those who have not spent five or seven or ten years in graduate school, we realise that we speak a different language to a certain extent; we realise that we see things, maybe most things, quite differently than they do, and this no matter what we are talking about, regardless of the actual subject of our studies; there is a different perspective on things, which is difficult to describe but definitely palpable and usually recognised. But when we interact with mature research workers we time and time again are forced to recognise how little we know and how much we still have to learn just to be able to exchange at a level that is sufficiently high to be interesting and useful.

When do we become scientists? Is there a moment at which we begin to feel that we are a scientist? Is there a point at which research workers consider someone to have become part of their peers? Is it possible to actually identify this in an objective way? We could say: when you have published a refereed paper, when you have published ten or twenty, or when your papers have amassed a certain critical number of citations; when you have given your first conference presentation, or when you have given ten or twenty of them; when you have given your first seminar, taught you first class, given your first series of lectures; when you have given your first invited review talk or your tenth. We could go on and on in this way, listing milestones and achievements, but can any of these actually determine at what point we can be considered or consider ourselves to be a scientist?

And what of this language, this language of scientists? Is it that a scientific training changes the way we understand the meaning of common words used in everyday language, or is it that the somehow different and possibly expanded worldview, to a greater or less extent, brought about by going through the process of scientific training, that everyday things, words and meanings are perceived and interpreted in a different and possibly wider general context that allows a more subtle understanding of not just these things relating to the specific subject of the training, but to everything else as well. Does this mean that it is not possible to agree on what different words mean by agreeing on a definition for them? Certainly not. Does it mean that communication between a scientist, whatever that is, and a non-scientist is not possible or not really possible because of the unbridgeable gap between their different worldview that causes an unsurmountable obstacle in their respective abilities to convey what each one is trying to express? Certainly not.

For all of the physical sciences, the universal language is that of mathematics, and it does not depend on culture, religious background, country, gender, skin colour, age, or whatever other superficial characteristic we might have inherited or learned from our family, friends, peers and larger social context. In any other field of science or anything else, for that matter, the specificities of language that are developed in time, and that we usually refer to as jargon, but which involves not just specific kinds of words, but also particular sentence structures, as well as speaking and writing styles. Are these somehow only accessible to those in the particular field of research?

Not really, are they? There is nothing fundamental about this jargon, this way of using words and sentences to express specific kinds of information. It is only a matter of learning it, which only requires exposure and time. To a great extent, to understand the language that is specific to a branch of science or other field of research, we do not even need to have formal training in that field, but only enough exposure to acquire these language-related skills.

Could a Galileo be imagined to be brought from his seventeenth century world into Roger Penrose’s twenty first century classroom on differential geometry in multi-dimensional non-euclidean spaces and understand even a handful of the words he would be speaking? Rather doubtful. On the other hand, could Galileo explain to Penrose his measurements and calculations on evaluating the acceleration of different spheres of the same size but of different materials on inclined planes? Absolutely! Could Galileo, given enough time, learn the vocabulary as well as the mathematical details required to grasp and follow Penrose’s lectures on curved non-euclidean spaces? Surely he could. Is there some kind of unique and special mindset that a scientist has, and that sets them apart, granting them access to hidden, secret aspects of the world, physical and even metaphysical? This was believed for many centuries and by most people, including those scientists themselves, but this is now not very believable, is it? Is it true that a career and a lifetime devoted to scientific inquiry and investigation, to the study of evermore complex subjects and mathematical formalism, the continual pursuit of deeper and more complete understanding of any particular problem in a field of scientific research work can lead to ever deepening insight into the function of and interactions between the phenomena that we observe in the physical world? Absolutely! Are these incompatible conclusions? Not in the least.

The importance of language for communicating, for expressing ideas and conveying what is intended to be conveyed, is enormous: there is no doubt about this. So great is it that it is far easier to be misunderstood or at least not well understood, than it is to actually succeed in making ourselves understood in the way we intended. Every research worker who has been to a conference, given and listened to presentations, and in that setting interacted with other research workers from different cultural and linguistic backgrounds knows how difficult it can be to express oneself in a way that ensures we can be understood, and how difficult it sometimes is to understand what others are trying to express and convey. Pushing this point to the extreme, we could conclude that we always only partially express what we want to convey, and always only partially understand what others are trying to convey. And yet, even if this is, in many ways, more of a tautology than something to be argued, we do succeed in conveying meanings, often of exceedingly high complexity and sophistication, especially in regards to a wide range of very technical scientific matters, that are understood by our peers, at least enough to continue the scientific dialogue and related research activities.

What about the way we function in our life outside of our research work: what do we believe about ourselves, about others, about the world and the universe? Do we believe in a God, a omnipotent or omniscient God, a benevolent God watching over us? Do we, as so many billions all over the globe, pray to our God for health and prosperity, for long life and success, for help and guidance through difficult decisions and difficult times, for a speedy recovery from illness, for our children, for our parents, for our brothers and sisters, for our cousins, uncles and aunts, for our friends? Do we believe in hell or in karma, in the existence of a soul, of an afterlife or in reincarnation? Do we believe that the societal rules of conduct defined by and through the religious and cultural frameworks that evolve within this society and that have been transmitted to us as they have to everyone else, have something inherently important, inherently fundamental, that they have something that inherently sets them above and beyond our ability or even our right to question their validity or just their practical usefulness? Do we believe that what we believe to be ethically right is actually right, and what we believe to be ethically wrong is actually wrong?

Do we question these beliefs that we hold? Do we question all of our beliefs and convictions? Do we recognise how strongly conditioned everything about our selves actually is? Do we recognise the extent to which this conditioning defines not only what we perceive, but also what we are actually able to perceive, what the way in which our attention is configured allows to perceive, irrespective of the actual biochemical and physiological function of the senses, nerve endings and central nervous system? Do we see what the eyes see, hear what the ears hear, feel the breathing of the body as it breathes, feel what the fingers and the skin all over the body actually feel? Or are all of these details ignored, overshadowed by our attention contracted and focused on some thought, feeling-tone or discursive conversation we are having with ourselves while going through the motions of doing what we do from the moment we wake up to the moment we go to sleep, never actually consciously seeing, hearing, touching and feeling anything other than our thoughts, our stories, our memories and our most often recurring and almost always paralysing feeling-tones?

Can we be said to be scientists—actual scientists, real scientists, true scientist—if we don’t question into absolutely everything about the way we know and learn, sense and feel, perceive and cognise, imagine and believe, conceive of and conceptualise, recognise and interpret, and in the end, how we express anything at all? Can we be said to be scientists if we do not strive to reconcile into a coherent whole all of the knowledge, beliefs and information we hold about ourselves and the world in all of its forms? Do most scientists live in this way: questioning thoroughly and uncompromisingly into everything without any discrimination nor censorship? No, they don’t; definitely not. Does, in fact, any working scientist do this? Maybe one or two here and there, but without any doubt, very very few, vanishingly few. Could most scientists, all of them even, live in this way? Yes, indeed, they could.

How is it possible, for example, to spend a lifetime studying and trying to understand the inner workings of supermassive black holes and everything about them, their vicinity and their interaction with and influence on these surroundings, and yet never wonder what happens scientifically speaking—biochemically, physiologically, metabolically—when we take a sip of orange juice or Coca-Cola, when we take a bite of a sandwich or piece of pizza? Does it make sense to spend so much time thinking and considering certain things, and not others, which are to all practical purposes infinitely more important for the survival of this being as a living organism? Does this behaviour seem contradictory?

Well, it may to some when put in these terms, but it is nevertheless normal, it is the norm, the standard way in which we tend to behave and tend to be, not just amongst scientists but amongst everyone, or at least, practically everyone. This separation, this segmented, disconnected, fragmented life filled with piles of bits and pieces, shards and splinters which together seem to make up its entirety, and this remaining so without triggering any sense of awkwardness or that there is something fundamentally off about this painful lack of coherence and cohesion between all of these separately considered broken pieces that what we nonetheless, maybe by force of habit, call our life.

To be starkly truthful, isn’t this questioning into absolutely everything, not merely hypothetically, but practically, not merely once in a while and not merely with our thoughts, but with the whole body-mind in each and every moment, again and again, and over and over throughout life, what every thinking human being should do? Do most people live in this way? No, they don’t; definitely not. Does actually anyone live in this way? Surely some do, but here again there is no doubt that their numbers are also vanishingly small in the global human population. Could most people, everyone even, live in this way? Indeed, we could.

With all of this in mind, having cast such a light on the subject, what would we say about what it means to be a scientist? What would we say about what it means to be a thinking human being? What would we say about coherence and cohesion in our own life? And what would we say to Wittgenstein or Popper about their notions of ‘the scientist’, ‘the life of the scientist’ or ‘the language of the scientist’?

Remarks on the relation of scientific theories to physical reality

A few days ago at the dinner table, my son mentioned that one of their Theory of Knowledge teachers had explained to them on that day that gravity was not a force, but instead that it was an epiphenomenon in the sense that it arose as a consequence of the presence of mass and energy in spacetime. My immediate reaction was to specify that this was true in the framework of Einstein’s Theory of General Relativity, but that as revolutionary, elegant, subtle, and incredibly successful as it was and is, General Relativity is, as all other theories are, a theory nonetheless, and that theories are descriptions of nature that we construct to explain and understand, at least partially, the phenomena we observe.

No matter what it is that we are observing, no matter how microscopically small or astronomically large, no matter how simple of complex, no matter how subtle or coarse, no matter how rudimentary or sophisticated the instrumental methodology, the observation or measurement is inherently distinct from the phenomena being observed, it is removed from it. This precedes conceptually the modern quantum mechanical tenet that the act of performing a measurement affects the system to which the measurement is applied. The former is a statement about the inherent distinction and separation between the phenomena, the observation and measurement of a manifestation of it, and thus also the interpretation that is given to the observation. The latter underlines the fact that, in the quantum mechanical view of the world, a system is a weighted probabilistic mixture of different states that coexist until a measurement is made, at which point the `wave function collapses’, forcing the system to be found in one of these possible states, and the instrument tells us which state that is.

The fundamental point I am referring to, which, when expressed plainly, is as obvious as obvious can be, is this: a description of a phenomena is not that phenomena—it is a description of it; a theory about the physical world, a theory about the physical reality we observe is not the physical world, it is not physical reality—it is a description of it. This is so easy to see that it is not debated and obviously shouldn’t be. However, we, as scientists and philosophers, regularly, and in fact, too often make statements, adopt stances and draw conclusions that undeniably demonstrate that this most fundamental point about the relationship of the theories (to which we tend to be so dearly attached) to physical reality is not well understood, and the point is muddled in our appreciation of the scientific process in which we are engaged.

physicsEquationsOnBlackboard

To hold that gravity is not a force but the manifestation of the fact that objects follow geodesic lines defined by the curvature of space-time which in turn is defined by the distribution of matter and energy illustrates the point well: we have substituted a beautifully accurate and successful description of the physical world as it pertains to the motion of bodies and particles, a jewel of a theory that is as elegant, far-reaching and as awesome in its descriptive as in its predictive powers, for an expression of how reality actually is, what gravity in itself is.

This is the first point I raised and explained in response to his mention of what the teacher told them in class. The supportive argument I used as an illustration of this was that in quantum field theory, another very successful theory that underlies all of modern particle physics, does, in fact, in stark contrast to Einstein’s classical Theory of General Relativity, treat the forces of nature as acting through the mediators of that force, bosons, that travel back and forth between the two particles, `carrying’ the force which is quantised in these boson force mediators. This is why it is described as a quantum theory of fields: everything is quantised into particles, including all the forces of nature, all of these particles are treated mathematically as fields pervading space-time, and gravity is quantised and carried by the graviton, even if the latter is the only one of the bosons that has not (yet) been detected. The other ones—gluons for the strong force holding quarks and anti-quarks together; W^+, W^- and Z^0 for the weak force responsible for radioactive decay; and photons for the electromagnetic force—have all been detected long ago and studied in a great deal of detail for decades now. Therefore, in the framework of the modern quantum theory of fields, gravity is a force mediated by the graviton; not an epiphenomenon that manifests as a consequence of the energy distribution dependent curvature of space-time. Furthermore, most attempts to reconcile General Relativity with Quantum Field Theory are based on the scientific framework defined by the second of these theoretical pillars of present-day physics in which forces are forces carried by gauge bosons.

Each time we succeed in understanding an aspect of the physical world more deeply and in subtler details, even if this understanding is flawed in some way that is not apparent to us, each time we succeed in developing a consistent theory with greater descriptive and predictive powers than the previous theory we had for this aspect of the observable physical world, the natural tendency is to claim and actually feel that now we finally understand how this works and how things are. But by the very fact that we have witnessed a multitude of both large and remarkable as well as small and incremental advances in our theoretical descriptions of the natural world, we are forced to appreciate the fundamental point that descriptions are only descriptions and will never be in any way equivalent to the actual phenomena that they describe.

In the same way that scientists and philosophers have pondered, discussed and argued about the meaning and consequences of the General Theory of Relativity on how we view nature and physical reality, they have done this, and in fact most likely to a greater extent, in relation to the interpretation of quantum mechanics, coming up with various paradoxes and conundrums in the process, which on the whole, instead of elucidating or clarifying issues, have only made the doctrines and theoretical implications appear stranger and more difficult to grasp. But here again, we suffer from the same problem: taking a description of reality, extracting meanings from this description about how reality or nature actually is, and then being intrigued and surprised by the counterintuitive consequences and paradoxes that arise from doing this.

To take the example mentioned above that deals with the collapse of the wave function, the fact that we describe our partial knowledge of the state in which the hydrogen atom finds itself as a superposition or co-existence of a set of different states with different probabilities for manifesting themselves, does not mean that this is so, it does not mean that this is how nature is. And the fact that when we make a measurement we find a particular state does not mean that prior to the measurement the system was in a quantum mechanical mixture of all the states. It is a description that works very well to describe certain physically observed phenomena in our laboratory experiments and therefore we use it. But it should not be interpreted as a statement about how nature in itself or physical reality in itself actually is; it is only a clever description that works in certain settings when certain boundary conditions are fulfilled.

This inquisitive human mind has always sought to understand. This understanding has grown evermore sophisticated and subtle over the centuries and millennia. The inherent human trait of clinging and holding onto whatever seems most solid in an attempt to make it feel most solid has led scientists and philosophers time and time again to believe in scientific theories as being expressions of how nature actually is, to equate a successful description of a physical phenomena to a statement about what the phenomena in itself is. Pursuing the intellectually challenging but stimulating and satisfying exercise of seeking increasingly sophisticated and subtle, extensive and ideally even all-encompassing explanations of natural phenomena through modern scientific theories has muddled the point further by continuing to ascribe to nature qualities derived from the interpretations we make of these theories. I think we should be more careful about this.