There is more subtlety to the evolutionism/creationism debate than many of the loudest voices tend to employ.
Continuing his exploration of space and time, Shahn Majid takes a look at science, religious belief, what we really know, and draws the line in the context of fundamental physics.
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It was the best of times, it was the worst of times; it was the age of wisdom, it was the age of foolishness; it was the epoch of belief, it was the epoch of incredulity.
-Charles Dickens
Last week the director of education for the UK Royal Society, Professor Michael Reiss, resigned after he was criticised for being ambiguous about the correct response to creationism, and to religion in general, if brought up by a pupil in a high-school science lesson. Perhaps his words touched upon a raw nerve in the scientific community or perhaps the point he wanted to make was just too subtle to be understood by the media in these troubled times.
Professor Reiss, who is also a Church of England minister, apparently suggested that in his experience it was more effective in such a situation to discuss creationism in the science class if only to show that evolution fits the facts better. Critics said that he should have had the teacher simply refer the pupil to religious education classes as creationism is not a scientific theory at all. Professor Reiss himself has stated that creationism is a `world view’ and that you have to discuss it to get through to pupils with such beliefs.
Was it over-reaction? A defender of Professor Reiss’ position on the BBC radio I heard argued that the creation myth was a metaphor, not to be taken literally. Hence scientists should not be so touchy. A critic could argue, however that if that were the case then that is exactly why the teacher should indeed to refer the pupil to poetry, drama or religious studies where parables as metaphor are appropriate. The problem is that as soon as you bring it into a science lesson you risk confusing science and parable. This is not helped by creationists who insist that the creation myth is not a parable but true and should at the very least be taught as a valid theory alongside evolution. This then makes a mockery of science.
Science, after all, is supposed to be searching for absolute truths verifiable (in principle) by anybody who cares to. It is supposed to uncover Nature using mathematical or logical tools, of course to formulate theories and hypotheses but to treat these with deep skepticism. Faith is anathema to science. Please understand me. Faith, a moral compass, spiritual values, all have a vitial role to play even in the life of a scientist. When you are stuck on a problem you have to put forth a hypothesis. You have to have some faith in it to take it seriously enough to explore. You may even have a ‘vision’ which is a kind of faith that guides your life’s work. But that’s all about the human process of research. The actual science is supposed to be based on fact and logic independently of how you got there, to the maximum extent possible. So faith is also the bit you are spending your life trying to squeeze out of the end product. It’s a complex dynamic which obviously can’t be grasped by pupils who have not yet understood what science itself is. They have to first learn what science is pure and simple and this is what confusing the issue so early on would deny them. This, in my opinion, is why many scientists are so angry about the no doubt well-meaning but highly dangerous position of the professor and other science educators with similar views.
Let’s see how these issues play out at the modern cutting edge of the most hard-core of sciences, fundamental physics. This is a vast and enormously successful edifice of knowledge which nevertheless has through the hard work of generations of physicists been boiled down to a mere handful of fundamental equations and beautifully simple ideas through which, in principle, we understand the physical world. There is still a certain amount of work to be done in particle physics. There is still a big problem which stumped Einstein but which physicists are now very optimistic about, namely the unification of quantum theory and gravity. But the consensus is that everything is going well and these are truly the best of times …
… but lets look carefully. Among the various hypotheses is at least one fundamental assumption that is not, in fact, supported by experiment. I refer to the topic of my new coauthored book, namely the true nature of space and time. Space and time provide the backdrop against which all of science takes place. It is a hypothesis or an act of faith that spacetime is a continuum. A continuum means that there is a smooth range of points in it, you can move any point arbitrarily close to any nearby one. All of mainstream fundamental physics is built on this assumption as a starting framework. Even quantum theory where things are `fuzzy’ has wave-functions defined over a continuum. Even strings in string theory are fundamental objects moving in … a continuum. Let me explain why this assumption is not only unjustified, it’s illogical even within science.
I will need two simple formulae and one diagram. The first is a formula that expresses the idea of wave-particle duality, that particles are also waves. We will take it in the form
L= 2 x 10⁻³⁷ / m
for the inverse relationship between the mass-energy m of a particle in grams and its Compton wavelength L in centimeters. The diagram shows this on the left in a log-log scale in which each notch on the scale is a factor of 10 billion (10¹⁰). Thus you can see that an electron has a mass of … and hence a wavelength of …. That’s much smaller than the wavelength of visible light, for example, and that is why an electron microscope can achieve so much better a resolution than an optical one. Clearly the wavelength sets the accuracy with which you can use a wave to probe something. Nothing can appear to the left of this left slope in the figure because if you try to make a particle lighter, it will just get bigger in wavelength and move up the slope. The second thing I need is a formula that expresses that gravity can cause space and spacetime to ‘curl up on itself’. We will take it in the form
L= 7x 10⁻²⁹ x m
…for the linear relationship between the mass m of a black hole in grams and half the radiius L of its event-horizon in centimetres. The event horizon is the sphere from inside of which even light cannot escape. It is the `bubble’ in spacetime that a black hole represents. This line of black holes is shown to the right in the figure. Nothing can appear to the right of this slope because if you try to make a black hole more massive it will just get bigger and move up the slope. Conversely, what we talked about last week was black holes evaporating and moving down this slope until they hit the left hand slope at a mass of 20 micrograms in the case of ordinary black holes. This is called the Planck mass. Now consider trying to probe a bit of the geometry of spacetime using different kinds of microscopes. In order to probe smaller and smaller distances you need smaller and smaller wavelengths of your test particle-waves, which entails heavier and heavier mass-energies for them. You follow the left slope until the test particles get so heavy that they themselves form black holes. At this point the test particle is curling up and destroying by its mass the very geometry it was trying to probe. From the figure we see that this happens at about 10⁻³³ centimetres. This is called the Planck length.
What this implies is that distances less than 10⁻³³ centimetres (i.e. 0.000 000 000 000 000 000 000 000 000 000 001 cm) are intrinsically unknowable. They therefore have no status within science. Continued reference to them is an unscientific belief. So, for example, when we look back in time and find that our Universe was smaller and smaller (the ‘Big-Bang model’ or its modern versions) we can extrapolate to a notional ‘point in time’ when it all began. But in fact our extrapolation can only work back to the point in time when the Universe was of Planck length size — earlier than that it did not even have a size! In short, the ‘ultimate creation’ question is not yet answered by science. And where does this problem with spacetime leave science in general? Does the edifice of physics come crashing down on our heads now that its very foundations are fatally flawed? Are these in fact the worst of times for our understanding of physical reality? Let us examine this.
First, physicists could dogmatically cling to a continuum assumption as an act of faith, now truly an act of faith as it has no scientific basis. The trouble with that is that these hypothetical particle wavelengths below the Planck scale render many computations in their theories infinite. For the most part physicists have discovered various tricks to make sense of and cancel these infinities. However, when it comes to gravity waves, i.e. particle-waves which are themselves made of ripples in spacetime, all these ideas so far have failed. There is still no theory of quantum-gravity unifying quantum wave-particle and gravitational ideas. Mainstream physics can continue optimistically down this path, perhaps replace points by strings, etc, but it is an act of faith that they will succeed.
Or, they can say that as scientists they are not wedded to that assumption after all. They can step back and consider notions of space and time in which there is no continuum in the formulation of the theory. I would not say yet that this is a mainstream point of view, but physicists can and in my view should do precisely this. Many physicists do freely acknowledge the problem but go back to the continuum as a practical approximation valid in most computations. They can artificially ‘cut off’ the offending less-than-Planck scale wavelengths in a practical but ad-hoc manner. This, unfortunately, still leaves you with puzzles and problems in the theory, such as the problem of dark energy. At any rate they are free to debate and question this most basic of assumptions. And meanwhile no, the edifice of physics does not come tumbling down in practice as long as the physics under discussion is far from the Planck scale (far from the cross-over point in the figure).
This then is the difference between science and religion. If you follow the Bible or any religious text as sacred, you cannot easily revise your central tenets. You may rather have to bend over backwards in your interpretation in order to accommodate the facts. Scientists on the other hand can, do and should question even the most basic of their assumptions. They sort their assumptions, quantify their impact and stand ready to throw them out if necessary. Far from being the worst of times, when something at the theoretical foundations of science is identified as fundamentally flawed it is cause for joyous anticipation as it means that we must eventually be about to take a leap forward in our understanding. And when theoretical questions such as the above combine with the possibility of experimental tests of Planck scale effects, as I hope to argue next week, it means that we are in fact in the most interesting of times.
Shahn Majid put together Cambridge’s On Space and Time and is Professor of Mathematics at Queen Mary, London. He’ll be filling us in on why these taken-for-granted dimensions of reality hold so much fascination for physicists, mathematicians, theologians, and philosophers.
For another perspective, see Church of England priest and physicist John Polkinghorne’s recent post.
[...] Interested in the science v. religion and creationism-in-schools debates? This article is actually almost too detailed for my stunted brain, but math issues aside, I really enjoyed [...]
Hi Transcendental Logic, appreciate your comments on your website. Sorry about the maths, but I wanted to give the proof for everyone to see for themselves (otherwise its just `he says, they say’). Thats pretty hilarious “Makes you want to pat their heads and demur, “poor thing, don’t worry, a good chunk of this business won’t turn out to be good science either!” ” Nice. I’ll be coming back to Zen philosophy several posts down the line, BTW
I wanted to get beyond the usual level of debate on this issue because its only by conceding that science also makes key assumptions and showing how it deals with them (irreverently) that scientists can explain to non-scientists how science actually works and how it differs from religion. If its just `you faith, me not’ then the creationists have an easy fight back `just a theory’ and people can’t understand what the difference is and why its so dangerous for science education.
What I’m amazed about is how unworried the American people seem to be that the Republican VP candidate seems to support teaching of creationism in science lessons. I guess there are other things to worry about just now.
Thank you for writing this! I’ve been trying to make this point for years. It’s the old “assuming a spherical horse” joke. Unfortunately I can’t remember the rest of the joke, so only people who already understand my point can follow me.
Faith means standing by your worldview and trying to interpret everything to fit it. Science is inventing a worldview and then doing your best to disprove it, and then choosing another, disproving it, and so on until you’re left with only the hypotheses that you’ve failed to disprove.
At that point, you’ll need to stop assuming a spherical horse so that you can disprove the rest of your hypotheses. If you’re lucky, you’ll be left with only one – not necessarily the coolest or most comforting one or the one that will please the most people, but if all the evidence supports it, you’re stuck with it. Unless you later manage to disprove that hypothesis too.
Religion doesn’t necessarily contradict the process of science, but it can interfere with it.
Also, thank you for the example. I’m no physicist, so I learned quite a lot from it. So the problem with the idea of a space-time continuum is not that the observable parts of it are wrong, but that it’s possible that the unobservable parts don’t continue along the same formula? What are the implications if this turns out to be the case?
Hi GSS, thanks for your comment. With reference to your question, the observable parts far from the `crossing point’ and inside the triangular wedge are fine. The unobservable parts don’t exist and one can simply forget them if you have any sense. But that means that as you approach the point where the unobservable parts are to disappear, our theory must break down as we have no understanding of or mechanism for this disappearance process. All of physics takes place in the wedge region so we aren’t concerned with the unobservable parts below it. But what we know is that as we approach the crossover point quantum theory and gravity musts start to interfere with each other in some unknown way. There is a kind of `sharp corner’ in science at this crossover point. Nature is not going to switch sharply from one to the other, the corner will be smoothed out somehow by all kinds of unknown physics as we approach the crossover point from inside the triangular wedge region. So we don’t know what happens at this crossover point and how it impacts the rest of physics inside the wedge.
That’s how I look at it. Many physicists assume the unobservable wavelengths are governed by the same formulae of quantum theory, get themselves into infinities and the subtract out those infinities by hand, a process known as `renormalisation’. This sometimes works but its a bit of a trick to `undo” the ill effects of the wrong continuum assumption. In particular, such methods don’t work for the gravitational waves — which is why we have no conventional theory of quantum gravity.
Also notice that humans, life, lie in the middle of the physical wedge region. I’ll be arguing in a much later post that this is because we somehow built physics around ourselves (a kantian foundation for modern physics).
David White emailed me a comment:
Greetings Jonathan,
This is an essay I blog posted 9/14/08 with a new, controversial and quite unusual viewpoint I hope will be widely discussed concerning the claims of the intelligent design movement.
It makes the case, primarily to religious moderates and others seeking a cooperative solution, that while faith and science are fully compatible, intelligent design is not only a bit crafty but, of all things, unscriptural. I do not believe this charge has ever been made before.
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Practitioners of “intelligent design,” much like Molière’s Physician in Spite of Himself, not only belie the true nature of their avocation and motives but also play fast and loose with a commonly held precept. They tacitly negate the clear and completely traditional parameters that illuminate the position of chance occurrence in our universe.
How often do we see people settle an otherwise contentious decision by tossing a coin or by drawing straws near the climax of one of those tense action movies? It seems fair to all because it’s random and impartial; and most people seem to acknowledge this without any hesitation. Here’s the larger issue. What proponents of so-called intelligent design have cynically omitted in their polemic is that according to Biblical tradition, chance has always been considered God’s choice as well.
Read full article:
http://phoebekate.com/2008/09/14/randomness-creationism-and-intelligent-design
Dear Shahn,
amusing. In your attempt to connect very different issues it is still important not be too creatonistic in the argument.
First the diagram. Justified as it is in the upper region it is pure assumption in the lower part, where you use it for your argument. Reminds of the extrapolations when people paint god as an old man with a long beard. In both cases you know absolutely nothing about the region you want to describe so you extrapolate vastly from what you know and believe (this is probably why god resembles Robinson Crusoe more then Britney Spears on most paintings, be aware of the subtleties here ;-) ). The continuation of the lines in the diagram and the conclusion that “smaller then Planck length does not exist” is pure faith.
Secondly you misquote string theory which according to your description is based on the faith of a continuum and pursuing your thought of line in the same box as creationism in this respect. That’s absolutely not true. ST does not assume a continuum. It reproduces a continuum in regimes where you expect it, which is good, but the mathematical formulation allows also for solutions which do not have an interpretation as a space time continuum. There are also solutions which describe discrete space-times in the appropriate sense.
Hi NoCreationist,
Many thanks — I’m ready to argue those two points, which are very good ones. On the first point: I am saying that assuming the conventional picture well inside the box where we know what we are doing and extrapolating down exposes that we do not know what is happening in the lower region –even within the assumptions that we started off with. So I am pointing to an inconsistency of conventional science within itself and not speaking (in this post!) about what replaces it. Surely then, the argument is within the conventional set of assumptions for quantum theory and GR as a conservative line of argument. I do agree that this points to a `hole in science’, but not how to fill it. Put another way, distances below the Planck scale have no current place within science as it is known so far as there is no evidence for them within what we know so far. That there is some future theory that could be found in which such distances do exist is an article of faith which is possible, but for which scientific evidence does not yet exist.
In truth my actual position on this is that the continuum, like the `real numbers’ that we learn about in high school are useful abstractions because they gloss over a certain level of detail, but thats all. Has anyone actually seen a real number that is not a fraction or a mathematical abstraction? How about Pi? Well, has anyone ever seen an exactly flat circle on a completely flat plane? Before answering that, bear in mind that the Earth as well as spacetime are a little curved. But thats a different story from commenting within the normal assumptions in Science.
On the second point, I chose my words carefully in speaking in the post about `no continuum in the formulation of the theory’. Maybe times have changed but when I learned string theory for the first time it was in an era when every talk in a theoretical physics seminar HAD to begin with a lagrangian which specifies the model, in a continuum, and this included string theory. Now, using this continuum classical theory and `quantizing it’, for example by a weighted average over all possible classical fields (Feynman path integral), you get to some kind of quantum theory from where, within the algebra of that theory, you can recover the classical continuum in, as you say, the regimes where you expect it. Well and good, so you can `extract’ other limits out of it which might better approximate a `foam-like’ structure at the Planck scale or a discrete structure etc, in the effective theory in certain regimes. It is a step in the right direction. But the theory itself is still founded on a continuum in its formulation. I really do not want to single out string theory here, this comment applies to the standard accepted notion of quantisation itself: the mainstream route in theoretical physics is to build the quantum theory on the classical one which is a bit like pulling yourself up by your own bootstraps. The Feynman path integral is a process that is cooked up so that the classical theory you put in has to emerge from the quantum because the quantum one is built around the classical. It works pretty well in practice but is it right? I’m not saying it could not give insight into the true nature of space and time but its illogical to think that it as fundamental as it kind of starts with the answer it wants to get in some limit. Its a bit like putting the cart before the horse.
So IF string theorists want to start with the Nambu-Goto lagrangian etc then they are open to my criticism. Alternatively, they can start with something more algebraic. Perhaps an operator formalism? But the specification of the various operators usually ends up invoking a classical picture. I actually agree with this line of thinking but take it further. The development of an intrinsically algebraic formulation of the theory with only indirect `by analogy’ reference to continuum geometry is called `noncommutative geometry’. I’ll talk about it in a future post but noncommutative geometers indeed let go of the continuum in this way. Now, string theory as I see it is a beast that can absorb any new idea on its cutting edge. So yes, I can name string theorists also working with noncommutative geometry and other non-continuum ideas. But one has to wonder how much of the baggage of string theory is then necessary from this new starting point (I don’t know the answer). My criticism at any rate is addressed to mainstream theoretical physics as it is usually presented.
Maybe a historical anecdote is in order here. When I was finishing my thesis in 1988, Ed Witten (The Ed Witten) gave a wonderful talk at Harvard on something like the `state of string theory today’. He even mentioned noncommutative geometry in his talk (but not as a starting point, rather as an algebra for sewing strings). In the reception at MIT that followed he asked me what I was doing. When I said that my thesis used algebra with different limits and did not begin with a continuum Lagrangian, Ed gave me a nice mini-lecture about how my approach must be wrong because you need a Lagrangian to conserve energy between a baseball bat and an atom. I remember it to this day though possibly in a garbled form (I was a bit too awe-struck to take it all in being a mere graduate student at the time). Some 10 years later I was visiting Harvard when Witten gave a similar lecture on the state of string theory. He began by saying that in his view there was no Lagrangian, that there was some unknown perhaps algebraic M-theory with different limits related by S-duality etc. So in so far as modern physics evolves one is speaking about a moving target. I rather think that the pendulum is gradually swinging to a more combinatorial or noncommutative or an even weirder direction for the deeper structure of space and time, but that the right starting point is still a (fascinating) mystery. Meanwhile, I hope its clear that I have nothing against string theory per se, this applies to much of conventional theoretical physics.
David White’s essay — an interesting read. Michael Heller in the book on Space and Time also has quite
a lot to say about chance and probability in relation to theology and in part to intelligent design. I wont try to summarise the arguments myself. But I would like to comment that pro-creationists also misuse probability in another subtle way. Probability is in fact a tricky subject even in science. When you hear a phrase in everyday speech like `all other things being equal, I propose …’ the intention is that a whole bunch of unknown variables not being quantified, we take them all with equal probability. There is a strong tendency to give the benefit of the doubt, to assign equal probability to things that we don’t have enough data to think about. By putting Intelligent Design up against actual scientific theories (and here I agree with David White that this is dubious) the proponents cynically rely on our natural tendency to assign if not equal then at least some unquantified probability to their `theory’ compared to evolution. It cant be quantified because its not science. But by mispresenting it as a scientific possibility people will start to give it some credibility by this `equal probability’ principle in the minds of nonscientists who have not had the time or inclination to look at the scientific evidence.
I should say also that use of probability is a grey area even among scientists. I remember some decades back Stephen Hawking saying on the Radio that in his view there was a 90% probability that Black Holes exist. I think I know what he meant but, how actually do you define the probability of a 1-off event. Its not like he meant that 9 out of 10 Universes have black holes. Statisticians are generally OK to think of probability as a way of representing lack of knowledge in a given situation or of summarizing repeated experiments, but not as an absolute quantity. Many people, on the other hand, WANT to think of probability as an absolute (this is compounded by its apparently absolute role in quantum theory) which is much more dangerous (I tend to take a Bayesian view that all probability is conditional).
These matters come back fundamental physics in the context of the `anthropic principle’ which some scientists (including some string theorists) advocate. Basically, an `explanation’ for why some of the parameters in our physical theories have the values that they do is put forward as: “The fundamental laws of Nature allow all possible values; we happen to be in a Universe where just the right values were assigned by Nature by chance. It seems unlikely to us but if they weren’t right we wouldn’t be here to see it.” In recent years this has been elaborated a but more as a `multiverse’; that all different values are actually assigned by Nature in different Universes and we are in the right one because life did not develop in most of the others where the values were wrong. Opinion differs among my colleagues but to me this is all a non-explanation. Science should try to understand why things are the way they are.
»Creation« (or »intelligent design«) – as usually understood by creationists and naturalistic atheists likewise – does not account for the transcendance of God [who is not an 'object' - nor a 'natural cause'; cf. Henri de Lubac below].
However, to believe (with science) that »the world is intelligible« is implicitely assuming the world is – in a sense – »intelligently designed«. It ist in that metaphysical ‘sense’ – prior and implicit to all science – that jews and christians can speak of »creation«….
Henri de Lubac: «Dieu n’est pas le premier anneau d’une chaîne. Dans la série de causes et effets qui compose ce monde, Dieu n’est pas le premier de la série. Dieu n’est pas «un point d’origine dans le passé»: il est «une raison suffisante dans le présent» (comme aussi bien dans le passé et l’avenir, – dans toute l’extension de la durée). Que d’objections tomberaient, que de malentendus s’évanouiraient, si cette vérité si simple était comprise! [Henri de Lubac, Sur les chemins de Dieu, Paris, Ed. Cerf, ISBN 10:2-204-08187-6]
Cool article you got here. It would be great to read more concerning this matter.
“Intelligent Design” is better described as “Intelligent Self-Design”. It comes down to three forms of causation: indeterminacy, determinacy, and self-determinacy…the last being a form of meta-causation.