The orientability of a manifold is a mathematical notion that is seemingly abstract and far-removed from reality. It is an issue dealt with in Topology, a modern branch of mathematics that studies properties of space. But in fact, it is one of the reasons why you and I could exist as living beings.
You see, the biochemical molecules that are responsible for sustaining life, amino acids for example, are chiral molecules. This means they have handed-ness. Chemists refer to them as enantiomers. For example, L-Leucine is different from D-Leucine in that they are mirror images of each other. And if you tried to take L-Leucine and rotate it around in space until it looked like D-Leucine, you couldn’t do it. They are mirror-images. And the difference is profound. Certain pharmaceutical drugs cure diseases in one enatiomeric form. Its mirror image could kill you. Indeed, that was exactly the reason why Thalidomide, which was originally designed to cure morning sickness, led to babies being born with no legs or arms. They used the wrong mirror-image form of the drug.
What does this have to do with the orientabiity of manifolds? Well, the mere fact that mirror images of things exist in nature that are not identical (have different chemical effects, for that matter) means that space is orientable. If space were a non-orientable manifold, this distinction would not exist.
Now, we are not actually certain if space is orientable or not. If it was not orientable, an astronaut could travel far into space and come back to earth to find that he is the mirror image of what he used to be! He would find his Heart on the opposite side of his body, and that mole on his left side of his chin would now be on the right! And if L-Leucine had traveled the same path that the astronaut had, it would have turned into D-Leucine! But not one know if such a thing is possible, hence we do not know if space is orientable or non-orientable. But, at least such a phenomenon does not occur nearby earth. Otherwise, we would have to fear for our lives to accidentally travel an orientation-reversing path somewhere in space!
If you are familiar with academic/scientific colloquiums and presentations, you will find this video absolutely hilarious. If you are not, well, then you are probably saner than any of the people laughing uncontrollably in this video.
The newest particle accelerator at CERN, the LHC, has been put on delay again. The problem is a magnet that apparently wasn’t being cooled fast enough. During a high-pressure test, the part collapsed and is now being fixed. While the accelerator was planned to launch in November, it may not be running until next year. This just demonstrates what a tremendously complicated project the LHC is. You have to bring together engineers and physicists and make both understand each others’ worlds. The engineer has to understand particle physics somewhat to know how to implement designs, and the physicist has to know some engineering to know what is feasible. For something this complicated and large scale, it would be a surprising if some type of a failure didn’t occur.
I am also highly dubious about this approach to doing physics. One only needs to look to history to see that the major revolutions in science came from theoretical insight, not some gigantic experiment that produced unexpected data to be analyzed. All the major developments, Newton’s mechanics, Maxwell’s equations, and Einstein’s GR, were developed from theoretical insights and philosophical motivation. NotÂ ONE of them were trying to explain some sort of puzzling data. Even for Quantum Mechanics, it took a little experimental surprises to jump start, but once it was off it was developed entirely theoretically. Schrodinger didn’t sit in a lab trying to empirically come up with the Schrodinger equation.
So to be spending this much money, time, and resources “just to see what happens” is wrong. One should have a theoretical prediction to go and test, not the other way around. Indeed, I fully believe that particle physics and the problem between GR and Quantum won’t be solved by these particle accelerators. I believe that someone smart will come along and come up with a new theory from amazing insight. This is the way physics has progressed for a while.
I find it very disturbing that physicists, and politicians convinced by physicists, are willing to spend the money and the resources to build something like this when it is likely that we will observe nothing new. We should at least have some theory to test, some reason for building the accelerator.
Now, I might be wrong. We may find unexpected data at CERN. But this won’t help in the least. Someone motivated enough mightÂ come up with some empirical equation that fits the data, but this is not progress. Physics needs unifying principles, philosophical ideas, that drive a theory to its inevitable conclusion. While new data may tell us that we are missing something, it can never tell us what is missing. And we already know that something is missing. There already are plenty of data unexplained. So why build another accelerator? At worst, it produces nothing. At best, it produces just another set of data we need to explain.
Recently, I finished reading a book called “The Trouble with Physics” by Lee Smolin, a theoretical physicist at the Perimeter Institute. The book is mostly a critique of why String Theory is bad for science. But on a more general context, it also talks about a certain type of sociology prevalent in the physics community that, Smolin argues, is hampering progress. I think the most representative example is his arguement about “Seers” and “Craftpeople”. Smolin argues that there are essentially two types of physicists. The more common type is the “Craftpeople”, someone who went into physics because they found themselves good at doing calculations and other “craftwork” that’s necessary to be a physicist. These people don’t think about stuff like philosophy orÂ epistemology and show strong deferrence towards well-known physicists, like Feynman and Wheeler. On the other hand, there are the “seers”, the ones who go into physics because they truelyÂ care about how the universe works at the most fundamental level. These people might be artists or philosophers if they had not gone into physics. The deep fundamental questions are what drives them, and they are not afraid to challenge established ideas and think on their own.
Now, I think his description of “Seers” and “Craftpeople” are somewhat true, but I also cannot help feeling that most people are a mixture of both types rather than clearly one or the other. He does make a good point about when each kind is needed though. For example, you need Seers during revolutionary times when the experimental data is clearly in disagreement with established theories, or the theories are not sufficiently clear or elegant. On the other hand, you need craftpeople to do the “hardwork”, to establish all the ramifications of a new theory. For example, you needed the “Seers” like Einstein and Dirac to challenge Newtownian Mechanics and establish Relativity and Quantum Mechanics, but needed “Craftpeople” like Feynman to work out all the applied theories like Particle Physics. Smolin also says that the “Seers” are usually motivated by philosophical principles to develop new theories while the “Craftpeople” are mostly occupied with not-so-elegant mathematical approximations and hard calculations to develop new models.
And thus, Smolin makes the point that in order to unify Quantum and Relativity, you need a “Seer”. Instead, we have had the “Craftpeople” dominant in physics for over 30 years, and their solution to the problem, String Theory, has failed specifically because it is, at best, a mathematical approximation and not a deeply motivated and philosophical theory.
I must say that everything he says is music to my ears because I have been sort of peeved at the “Shut Up and Calculate” mentality that I have found in physics so far. I was glad to know that talented physicsts, like Lee Smolin, cared about philosophical issues as much as I did. On the other hand, I also cannot help but wonder just how much of his arguments are oversimplified. Are most physicsts really so dumb as to deliberately ignore philosophy and epistemology? Can the lack of progress in theoretical physics for the last 30 years really be blamed on the “craftpeople”? If I become a physicist, it seems like there is treacherous road ahead of me.Â
Hi everyone. I guess I’m in the blogosphere now. I read somewhere that over a million blogs are created everyday. So I guess this is one of them. I hope to share my thoughts and frustrations on this blog in the future.
So I will begin by introducing myself. I am currently a sophomore at Swarthmore College. I recently declared a major in Mathematical Physics. In addition, I am planning on a music minor. My interests in math include Foundations, Axiomatic Set Theory, Point-Set Topology, and Geometry (Differential). My interests in physics include General Relativity, Newtonian Mechanics, Maxwell’s Eqations, and philosophy. In terms of music, my favorite genres are the Baroque and Progressive Metal.
I recently discovered a great artist, called Neal Morse. He is a prog-rock composer, and his conceptÂ album “?” (yes, its called question mark) is one of the greatest albums I have heard in a long time. It’s not prog-rock per se, but it uses alot of mannerisms of that genre without the heavy guitar riffs. I have been listening to it constantly. It’s quite catchy, but it a good way. Now it is a Chrisitian album, which turned me off from it a little bit. Some parts do get preachy. But then I remind myself that most of Bach’s wonderful choral music are also religious in theme!