Well, that’s it! I have just finished teaching the last class of this quarter. The rest of my lecture notes for the class are here. I covered less than what I had originally intended. The last sets of notes are sketches of the ideas of holomorphy and basic aspects of supersymmetric vacua, plus some basic intro to the (softly broken) minimal supersymmetric standard model. So after getting five extra minutes of free time to celebrate the end of the quarter, there is all the rest of the backlog of work that I have to plow through.
I’m going to be nice to the readers and restrict my rant to my research (the rest would take some considerable extra rant).
I’m finally restarting some of my old work on numerical simulations that was left on the wayside when the teaching interfered. I successfully compiled and ran my first “Hello world!” program on MPI on my computer. I’m learning some proper parallel programing this summer. I’m also considering learning some python and javascript. These languages were not part of my programming education over 15 years ago. In my days, one learned Basic, Fortran (Basic was a watered down version of Fortran without all the pesky formatting), Pascal (to make you ordered and to learn how to use pointers) and then perhaps C (which I did learn eventually). I also had to learn to program in Assembler for one of my lab classes. The final was writing an Assembler code to compute factorials with input from the keayboard and writing the number on the screen. The computer I had to do that for was old even by the standards of those days.
I’ve also upgraded a whole lot of software that broke down when I upgraded the system last year and that I was not using. Now I needed it again, and I am happily running the codes again.
Now that all of that is working again, I also have to finish those four to five or maybe even six, seven or eight papers I’ve been working on that have also been derailed over the course of the last few months (again, blame the teaching). I’ve stopped counting how many stalled projects there are.
Speaking of parallel programming: Have you taken a look at Fortress?
It’s designed with parallelism in mind.
If I understand correctly, certain for loops are automatically executed in parallel, if possible.
http://projectfortress.sun.com/Projects/Community
Hi Jan:
No, I didn’t know about fortress. It seems to run in Java.
However, I’m using the GSL libraries heavily, so I’m not sure how to patch them up (I’m still trying to get up to date in programming languages, so this would take a while).
As far as I know MPI is more portable (more widely accessible), and then I should be able to run code in supercomputers with no extra effort eventually.
Why would supersymmetry be factual? Protons do not decay, axions are not detected, no accelerator even hints at SUSY channels, dark matter is conjecture (curve fitting). The Standard model arrives massless, the Higgs refuses to surface. SUGRA is a disaster. Contemporary physical theory is a compendium of mathematically elegant interpolations deeply incorrect versus prediction even as an approximation.
Physics has choked on chirality since Newton, barely pausing given the Yang and Lee empirical heresy. Mass is fermionic but GR cannot swallow fermions. Mass distribution chirality is an extrinsic property and emergent phenomenon. Physics knows chemistry cannot harbor the answer any more than a semi-literate grain miller’s son could influence physics (one Green exception noted).
Somebody should look. No Equivalence Principle test (the world line of a body immersed in a gravitational field is independent of of its composition and structure) has returned other than a null output since the mid-1500s. Composition is beaten beyond death, pulsar/star binary included. Quantum gravitation theories supplement Einstein-Hilbert action with an odd-parity Chern-Simons term. A parity Eotvos experiment performs in existing apparatus using commercial materials with validated protocols run by disinterested personnel. When does physics test structure and find its EP parity violation so theory can be rewritten to predictively perform?
Dear Al:
Just because we have not seen a proton decay, it does not mean that it can’t happen. We can only have a bound on it’s lifetime. And just because we have not detected an axion, it does not mean that they are not there. There is a window for axions that is not excluded by current experiments and astrophysical observations of supernovae cooling. Similarly, speculation in theoretical physics is about possibilities that have not been already ruled out by experiment. This includes supersymmetry.
Dark matter is not a conjecture. It has been seen in telescopes via gravitational lensing and rotation curves in galaxies. It is also part of the data that WMAP has spit out.
It is considered a well established observational fact and the various measurements point towards it’s existence in what is called the concordance model in cosmology: all experiments seem to agree on how much dark matter there is. Competing models to explain these features that do not include cold dark matter have not held up to the scrutiny of the scientific community, even if there are a few who have not given up on their pet theories.
It’s just that we don’t know what dark matter is made of. A connection to the Standard model is speculative, but such a hypothetical connection is being tested in direct detection dark matter experiments.
I love Java. It’s like C but it’s so tightly cast that it forces you to correct your errors BEFORE your crashes the computer. It does parallel processing on a weak scale. (By weak, I mean that it allows multiple threads. I spent a couple decades designing mostly Xilinx FPGAs, now those give you true parallel processing; one Virtex-5 chip can theoretically do 20,000 16-bit adds in a single cycle. A cycle is around 2 nanoseconds.)
I second Uncle Al’s complaints but worse. I reject all use of symmetry in the foundations of physics. If you have a set of differential equations, I love using symmetry to solve them, but I reject making assumptions about the symmetry of the universe.
From my point of view, symmetry got under the skin of physics because experimental results are most easily expressed as symmetry rules. So they’re a convenient way of modeling so as to match experimental results, but there is no convincing reason why reality should have been designed with symmetry.
Dear Carl,
comments like yours (about the symmetries) are simply stunning for people like me. I just can’t comprehend how someone can think in your way and fail to immediately see that her or his thinking is demonstrably, fundamentally, and completely wrong.
Symmetries that are important in physics are not arbitrary “assumptions” that are “used” to derive uncertain results. Instead, they’re experimentally demonstrated facts. And they’re damn important. Let me tell you why.
In science, one cannot work with dogmas. So if there is a question, such as “are the dynamical laws of Nature rotationally symmetric?”, one must be a priori open-minded. If one honestly gathers evidence relevant for this question, he will see very clearly that the evidence overwhelmingly favors the Yes answer.
Indeed, such a result couldn’t have been quite known from the beginning, and from some philosophical viewpoint, one might expect that it is extraordinarily unlikely that Nature would respect such a symmetry – and situations related by symmetries “should” have virtually nothing to do with each other (that’s what you expect). But the beauty and meaning of science is that hypotheses can be falsified, and this one is an example, too.
If one actually makes tests, it can be easily demonstrated that the situations related by symmetries are surely not “uncorrelated”. In fact, one can show that they lead to identical results, within an error that can be experimentally proved to be by many orders of magnitude smaller than the initial expectations of an “asymmetric thinker”. Nature is not a scamp who creates lousy products that don’t fit together – like you. Nature actually does things right, and symmetries are a key part of the meaning of “being right”.
Such a conclusion – the existence of a symmetry – is very important exactly because it could have been unexpected by some people at the beginning (and it is unexpected even a posteriori, after the experiments, by other people whose brains are very slow). So most theories that one could invent at the beginning contradict the existence of an exact or “almost exact” symmetry.
Let me emphasize once again that this contradiction is not a contradiction with arbitrary assumptions that someone wanted to impose because he was bored. It is an actual contradiction with the experiments – whose results have been organized and reduced to make it possible to create certain conclusions (and falsify huge classes of theories) very quickly.
If you decide to deny that the laws of physics are exactly or “almost exactly” symmetric with respect to things like the translations, rotations, Lorentz symmetry, U(1) rotations linked to the electric charge conservation, and other things, you are simply denying the reality, and it is virtually guaranteed that all theories that you will invent will be pure crap because the symmetries are among the most important criteria that distinguish promising theories from those that are empirically wrong.
Best wishes
Lubos
Lubos:
Please watch the tone. Carl is giving an opinion, just an opinion, of his predilections for reasoning with symmetry in physics. I don’t agree with it, but he is entitled to it.
Lubos, I agree that theories need to match experiment. But that does not mean that theories should be derived slavishly from symmetries the way a student guesses the method of solution from the terse answer provided for the odd problems at the back of the book.
One does not need to base a theory on symmetries to get symmetries. Solve enough differential equations and you will find that conserved quantities and symmetries pop out of them whether you want them or not. One can’t avoid symmetries.
All that matters is that what is observed is consistent with experiment. The underlying theory does not have to be constructed from the symmetries in order to give predictions that match them. See Chapter 12 of David Bohm’s The Undivided Universe, “On the Relativistic Invariance of our Ontological Interpretation” (of quantum mechanics) for an example with Lorentz invariance.
Newton did it right. He derived the Kepler’s laws (which are a type of symmetry i.e. conservation of angular momentum, etc.) from a simple equation of motion. And in fact, F_x / m = -GMx/r^3 is (a) more general than Kepler’s laws, and (b) is mathematically simpler. So this most important step in physics began not by defining the theory in terms of its symmetries (as is done nowadays) but instead by postulating a simple relation from which the symmetry can be derived.
The best evidence that physics jumped the shark with symmetries is the necessity of theories that use symmetry breaking. Second best is that thousands of physicists have used those methods to unite gravitation and QM and have failed.
Dear Lubos,
“comments like yours (about the symmetries) are simply stunning for people like me. I just can’t comprehend how someone can think in your way and fail to immediately see that her or his thinking is demonstrably, fundamentally, and completely wrong.”
That’s funny. I feel exactly the same way about you and your incessant insults to people like Sabine Hossenfelder, Lee Smolin, and Peter Woit. As well as your sexist insults. Also, your inaccurate assessments of people and their attitudes towards physics:
“Sabine Hossenfelder wrote a very revealing story about her discussion with a yellow cab driver. He was absolutely thrilled by physics and string theory: she just hates it. This is not the first time I learned about it: she sent me quite a lot of mail explaining how she hated theoretical physics.
This is the result of the “politically correct” process of filling science with mediocre people who have no aptitude to study it and no love for it – they end up being unhappy themselves, and they’re doing everything they can to spread the vitriol around and to discourage other scientists, by emitting tons of trash about their troubles with physics. I just hate them. And I hate all the people who have pushed people like Ms Hossenfelder to the physics community. They’re my enemies.”
You’re a complete nut-job, Lubos. Actually, Sabine is attending SUSY ’09, and said to that driver: “I’m not a String Theorist, but yes, it’s interesting.” Does that sound like someone who hates theoretical physics? Why are you letting your (unfounded) dislike for these people spew out such lies that can be easily refuted?
“Nature is not a scamp who creates lousy products that don’t fit together – like you.”
Another reason why you are an a****le.
Dear Dave:
With comments of this nature, please put your name to it. Anonymous insulting is the refuge of cowards and trolls of the internet. Whereas if I can tell who the parties to the fight are, I can start munching on the popcorn and watch the spectacle
.
Dear David, just look how hugely unfair you are.
A crackpot writes nonsense about the non-existence of symmetries, I explain why it’s nonsense, and you tell me “watch my tone” because he is only giving his “opinion” when he is attacking the very fundaments of physics as a science while I am apparently not.
But when an anonymous vitriolic commenter just attacks me, without giving any material content to it whatsoever, you are enjoying it immensely, preparing popcorn for the great spectacle, and prove your excitement by a smiling.
People like you are a part of the problem, a part of “trouble with physics” so to say.
I have no idea how Hossenfelder at SUSY got here, but I personally think it is a theft if someone gathers money for her presence at a conference about SUSY – a framework she dislikes, she doesn’t believe, she has never made any calculation about, and that she has just attacked in dozens of postings on the blog by pure vitriol.
But no one cares. The Academia is literally built at similar parasites, and because pretty much everyone in it is a part of this process of stealing money from the taxpayer, they are supporting each other even if they know what the reality is.
Hi Lubos:
I know, I know… Not fair…
I just get annoyed with the extra -`like you’ tossed carelessly here and there. Let me quote you:
“Nature is not a scamp who creates lousy products that don’t fit together – like you. ”
The absence of those two words would have gotten a free pass
I find that it’s hard to defuse a name calling explosion in the making.
Lubos said:
“I have no idea how Hossenfelder at SUSY got here, but I personally think it is a theft if someone gathers money for her presence at a conference about SUSY – a framework she dislikes, she doesn’t believe, she has never made any calculation about, and that she has just attacked in dozens of postings on the blog by pure vitriol.”
What if Feynman wanted to go to a string theory conference before he passed away? It’s a framework he disliked, didn’t believe, had never made any calculation about, and that he attacked many times even when speaking to John Schwartz himself. Now there’s (I believe) an excellent counter-example. Clearly, Feynman doesn’t deserve the kind of description which you used for Sabine Hossenfelder in your original post on your blog (which I quoted in another comment). Both disliked string theory, but both found it interesting. I’m NOT saying that Hossenfelder (or anybody on this blog for that matter) is on par with Feynman as a physicist.
I had plenty of points to back up my attack on your blog post (and insults) about Ms. Hossenfelder, but you deleted my comments. You will delete the comments of anybody who disagrees with you about your descriptions of people you consider your “enemy”. I suppose if you were at Caltech in the 80′s studying string theory, you would have thought Feynman was your enemy, and called him a “parasite” too.
Ok Dave:
Take it outside. You need some air.
Physics and science in general is not a philosophical or theological belief system where you can express laxly your implausible “beliefs”. Your opinion must be based on facts or at least on a well established theoretical and mathematical reasoning. I too could say that I don’t believe in the evolution theory. Such statement is useless and just adds noise.
I think that people say a lot of distasteful things, but one should always try to stay focused on whether the person is making a contribution to knowledge within their field. I think that the critique offered at TRF often is a great service to those who are trying to weed out poorly thought out papers from ones that have potential to help solve the current unification problem.
If someday another theory emerges that does away with the framework provided by the last 300 years of physics and successfully unifies all our knowledge, that would be fine. The truth is we are stuck with the theories we have because they have proven to be so successful, and much of that success is due to the simple principles those theories are based upon.
Since we are stuck with such theories, then we are stuck with their shortcomings and limitations. Our perfect theories are massless, which comes in conflict with our imperfect massive world. So what are we to do? Deny existence?
The conflict arises in the choice of standards. Those with low standards may be satisfied with an ad hoc approximation that ignores the realm beyond the planck scale. Heck, if we just ignore all the little details of the universe, then maybe all the bad things will go away.
However, no matter how hard we try to ignore reality, we come to the inescapable conclusion that there is a fundamental length in our universe, and there is a natural relationship between it and our notion of mass. We are also forced to conclude that beyond the planck scale exists a realm of seemingly infinite energy and mass, with us merely being some sort of disturbance on its surface.
In the end we can not accept that bosons and fermions are related only trivially. There must be some deeper connection and to that end we must change our frame of mind and accept that the world we see is merely a projection of something larger and more complex.
In conclusion, I don’t think its wrong to criticize, as long as such criticism is justified.
Since we have been discussing symmetries, I suggest that Prof Berenstein perform the following experiment. Go to Lubos Motl’s blog and put up a comment calling him what he called you, a parasite. If he deletes your comment and bans you, you can perform a perfectly symmetrical operation over here.
In fact, LM has been banned from just about every serious physics blog. So banning him here would also establish a symmetry.
Oh c’mon!
I’ve been called much worse than a parasite before. I’m not going to escalate this. It is easy to get angry at words or the people behind them when they are in print. Part of the problem is that when people vent on the web there is a permanent record which leads to a ‘he said, she said’ scenario and it is easy to revisit the wrongs inflicted on us.
In normal conversations it would be patched up with a handshake and a beer or something and everyone would be happy.
Luboš is a powerful, tight, original thinker and a wolverine for attacking questionable reasoning. However, no axiomatic system is stronger than its weakst axiom. Euclid is incomplete for his deficient Fifth Postulate. Noether’s theorems absolutely coupling symmetries to conserved currents (observables) require continuous or approximately continuous (e.g., Taylor series) symmetries. Parity is an absolutely discontinuous symmetry and an external symmetry coupling to translation and rotation. Noether’s theorems are impotent against parity violations.
Perturbational string theory uses BRST invariance to unite the effects of a massive body and an accelerated inertial frame. ALL quantized gravitations supplement Einstein-Hilbert action with an odd-parity Chern-Simons term. There is every reason to believe macroscopically and chemically identical, opposite geometric parity atomic mass distributions will violate the Equivalence Principle and empirically falsify BRST invariance in string theory. GR will be demoted to a heurisitic, conservation of angular mometum will have a parity violation, somebody will visit Sweden.
Commercial hydrothermal growth (Sawyer Research x-plate process) is kind for providing near perfect opposite geometric parity atomic mass distribution test masses to kg scale: enantiomorphic space groups P3(1)21 and P3(2)21 quartz. 25 years of string theory and SUSY excuses could be resolved by a 90-day parity Eotvos experiment. Stop whining and start looking.
http://www.npl.washington.edu/eotwash/publications/pdf/schlamminger08.pdf
The apparatus is superb. Its loadings have been unconscionable crap. The proper challenge of spacetime geometry is test mass geometry – not composition.
Love and kisses, Luboš! Theory predicts what observation tells it to predict. Somebody should look.