Natura non facit saltus
Debunking the Paradigm Shifters
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Thursday, Mar 29, 2007
Definition of Theory
I posted this definition of Theory on Conservapedia.
For some reason, the anti-evolutionist make a big deal out of saying that evolution is a theory, not a fact. The evolutionist, in turn, make a big deal out of saying that a scientific theory is the highest and most perfect from of knowledge that we have. Both sides are a little nutty. Scientific use of the term "theory" is just the same as the common usage, except during evolutionism proselytization.
I am finishing Smolin's book. Some of it is over my head, but he makes a convincing case. Did you read it? He gets really flaky in the last chapter on women in physics and affirmative action. He says that basically he has never seen an affirmative action candidate for some hotshot physics position who wasn't arguably the best candidate. I don't think that many big law firms would share that opinion.Yeah, Smolin gets a little kooky at the end. I was surprised at how he was influenced by Paul Feyerabend. There's a guy who really has some nutty ideas about how science really works.
Smolin cites this MIT report as evidence of blatant prejudice. I just skimmed it quickly, but it appears to me that the report failed to find any significant bias against women. The women said that gender bias is not hindering their careers, and their biggest complaint was that the department could be doing more to make them feel more included.
The argument for affirmative action would be that cronyism and subjective measures work against women. If that were true, then I would expect that women would have a much harder time in the soft sciences than in the hard sciences. In fact, it is just the opposite.
I did like the way Smolin exposes the failure of String Theory as a viable theory of quantum gravity. The string theorists act as if they have already solved gravity and they are moving on to particle physics. Ed Witten is fond of saying, "‘String theory has the remarkable property of predicting gravity." In fact, they've added nothing to our understanding of gravity, and ST is not able to reproduce relativity theory.
Physicist Laurence Krauss says, in a current interview:
The debate is twofold. A: Does string theory have anything to do with the real world. And B: Is it, as I like to put it, ready for prime time? Is it worth all the hype and has it made any progress? I think the answer is no. It's been incredibly unsuccessful. It's a theory in crisis — it hasn't really achieved any of its major goals as espoused 20 years ago. I'm not saying a physicist shouldn't be looking at this stuff. I just think it's not worthy of a lot of attention. Now, there are no really good alternatives, but I can guarantee when there is, everyone is going to drop string theory like a hot potato and go onto something else.Here is a recent debate over string theory:
Brian Greene (left) and Lawrence Krauss (right), participated in a String Theory Debate last night at the Natural History Museum (Smithsonian Associates Program), with Michael Turner acting as moderator.See also this Science magazine summary.
Krauss got the better of the argument, but I thought that he was too easy on Greene. Greene argued that ST had succeessfully combined gravity with quantum theory in a consistent manner, and wasn't even challenged on the point. Greene is not telling the truth. ST does not include gravity, and does not give a consistent way to give a quantum calculation of anything.
Greene gushed with enthusiasm for ST, saying things like this:
When this points to it, and this points to it, and this points to it, all the spokes on the bicycle wheel point to one direction, you begin to have confidence that you are going in the right direction.This is so nutty that I cannot even figure out what he meant. The spokes in a bicycle do not point in the direction that the bicycles is going. I guess you could say that the spokes on a wheel all point to the axis at the center, but that tells you nothing about whether the bicycle is going in the right direction.
Actually, now that I think about it, maybe this is a good quote for characterizing the thinking behind ST. Some physicists think that they are going in the right direction because they found a few mathematical consistencies, but those consistencies say nothing about any real-world physical problems.
Monday, Mar 26, 2007
The failure of String Theory
Clifford V. Johnson, writes, on the Physics blog Asymtotia:
Peter, Please just answer the physics questions asked of you, and stop referring us to your book. ... I asked you whether or not you are now claiming that your declaration (with no proof) that string theory has failed or is wrong (or any of the many ways you are publicly on record for saying this) is still your central claim. ...Clifford refuses to read the book, but he'd get part of the answer by just reading the title, Not Even Wrong. It is not that String Theory makes demonstrably wrong predictions, but that it fails to make any testable predictions at all. String theory has yet to yield a particular definitive test, or to produce any models that resemble any known particles or forces.
Physicists use relativity to explain gravity, and U(1)xSU(2)xSU(3) gauge theory (aka the Standard Model) to explain the electromagnetic, weak, and strong forces. These theories are extremely successful, altho there are some unexplained anomalies like dark energy. String Theory exists as part of a misguided philosophical program to unify these theories and more tightly couple the forces.
String Theory is said to be consistent with relativity because relativity predicts that empty space will be Ricci-flat, and that ST also uses Ricci-flat spaces. Also, hypothetical quantizations of relativity always predict a spin-2 graviton (that has never been observed), and ST also predicts a spin-2 particle.
ST is hoped to be a viable quantum field theory because some of the infinities that would ruin the theory are known to cancel. Existing gauge theories are able to make very accurate predictions by computational procedures that cancel all the infinities. Nobody knows how to calculate anything measurable in ST. The known particles are quarks, leptons, and bosons, but no one has figured out how any of these would have a place in ST.
Where ST has made predictions, they are contrary to observation. ST predicts at least six extra dimensions, stringy electrons, dozens of superparticles, and a gigantic vaccuum energy. There is some possibility that superparticles will be observed, as some theorists predicted these long before ST and there are independent reasons for thinking that they may exist. The other predictions are hopeless.
Asymptotia wants proof that ST has failed. Failure is an understatement. Most of our smartest theoretical physicists have worked on ST for the last 30 years. While it has produced some impressive Mathematics, it has produced nothing of significance to Physics. There is not one formula, particle, principle, force, computation, or other result that the ST proponents can claim to have some tangible connection to actual physics.
The ST proponents argue that despite the shortcomings, ST remains the "only game in town" and is the best hope for replacing current (extremely successful) theories with a more tightly-coupled theory. They are delusional. They are following some peculiar mystical vision of how they think that the universe ought to be, instead of following physics.
Harvard string theorist Motl attacks critics by reciting silly myths about Galileo and Einstein, and calling the string theory skeptics stupid and other names. Today his blog has this gem:
Chicken Little Society has been around for centuries ... a certain kind of human stupidity simply can't be eradicated: Columbus was criticized for his plans to try the Western route to India because this reasoning based on the round shape of Earth was pure theory but it would surely be a waste of sailors in practiceThose who criticized Columbus were actually quite correct. They correctly calculated that Columbus would never make it to India.
Friday, Mar 23, 2007
Bush on who is winning in Iraq
Someone sent this proof that Pres. Bush is a liar, from the Wash. Post in December:
As he searches for a new strategy for Iraq, Bush has now adopted the formula advanced by his top military adviser to describe the situation. "We're not winning, we're not losing," Bush said in an interview with The Washington Post. The assessment was a striking reversal for a president who, days before the November elections, declared, "Absolutely, we're winning."But here is the context for the original quote:
Q Are we winning?It is clear that Bush was saying that we are winning the global war on terrorists. The Iraq War is just a battle in that war, he says. The people have the full story on what is happening in Iraq. I don't see any lies.
Update: When Bush said, "We're not winning, we're not losing", he was just quoting General Pace. It wasn't Bush's phrase.
Saturday, Mar 17, 2007
The geocentric theory is a system for describing the universe with Earth-centered coordinates. It was extremely popular from ancient times until about 1600, as it had better agreement with observation than any alternative. Ptolemy's model was particularly effective at cosmological predictions.A lot of people like to make fun of the geocentric theory, or to use it as an example of ignorant and erroneous thinking, like the Flat Earth Theory. They seem completely oblivious to the fact that they are relying on physics that is 100 years out of date.
Tuesday, Mar 13, 2007
A Call to Cool the Hype
The NY Times reports some inconvenient truths:
Hollywood has a thing for Al Gore and his three-alarm film on global warming, "An Inconvenient Truth", which won an Academy Award for best documentary. ... ...If present trends continue, the best estimate is that Earth's sea level will rise about a foot over the next 100 years. A drastic cut in CO2 emissions might cut the increase to 10 inches. This might be accomplished by either a shift to nuclear power or a reduction in our standard of living. Nothing else would have much effect. A shift to nuclear power would have other environmental benefits as well.
There are also cosmological and other factors beyond human control. These will probably start a global Ice Age in the next 5k years or so. It is possible that the CO2 global warming is just what we needed to stave off the coming Ice Age. It might also be true that we'll be better off with a higher sea level.
Wednesday, Mar 07, 2007
Bush will not pardon Libby
Not now, anyway. I am baffled by those who are pushing for Pres. Bush to pardon Scooter Libby. I have defended Libby here on this blog, but a pardon is not appropriate.
Prosecuting Libby is exactly what Bush wanted. If Bush did not agree with the prosecution, he could have stopped it with a single phone call. The obvious inference is that Bush wanted to make Libby a scapegoat for the Plame controversy. The conviction insures that the legal process will continue, and White House officials have their usual excuse for not commenting until everyone has forgotten about it.
If Libby had told his story, and explained how he was telling the truth, or was mistaken, or was forgetful, or was overlooking a trivial detail, or whatever, then I might feel differently. But he chose to keep his mouth shut, and he will have to live with the consequences.
It is a little strange to hear Libby jurors say that the wrong man was being prosecuted, or that Libby should not goto jail. So why did they convict him?
Tuesday, Mar 06, 2007
Scooter Libby convicted
Okay, I was wrong. I thought that Libby would be acquitted. We may soon know more, as the jurors talk.
My first reaction is that the defense was weak. It mainly argued that Libby could have been mistaken, or he could have been a scapegoat. Libby needed to take the stand, and give his story. He could have stuck by his contradiction of Russert, or explain how he was misinterpreted, or explain how he was mistaken, or explain how he was trying to comply with the feds, or something. But he had to have some story.
My guess is that lawyer Ted Wells talked Libby out of testifying because it is too risky. The risk was that Wells would lose control of the case if Libby's cross-examination strayed into unexpected territory. Defense lawyers hate to put the defendant on the stand. But the real risk is going to prison, and Libby should have known better.
Thursday, Mar 01, 2007
Hansen opposes IPCC report
John Horgan joins the leftists who argue that the Bush administration has been anti-science, and says:
Some of the Bush administration's actions have been almost comically incompetent. Last January, for example, George Deutsch, a public-affairs officer at NASA, tried to prevent the space agency's James Hansen from speaking to the press about the dangers of global warming. Andrew Revkin of The New York Times quickly exposed the attempt to censor Hansen, ...But here is what Revkin wrote:
The top climate scientist at NASA says the Bush administration has tried to stop him from speaking out since he gave a lecture last month calling for prompt reductions in emissions of greenhouse gases linked to global warming.Note that there was no attempt to discourage him from speaking on science; only a feeble attempt to limit policy statements.
What Hansen says now is that the IPCC is understating the expected sea level rise from global warming. Maybe he's right and the rest of the world is wrong, but he doesn't speak for Bush administration policy.
Meanwhile, Al Gore complains that mass media bias is keeping a lid on the global warming story:
He noted that recently the Intergovernmental Panel on Climate Change released its fourth unanimous report calling on world leaders to take action on global warming.Gore sure seems to be getting plenty of publicity for his cause. And he is getting it without having to answer tough questions.
Cartoon compares Science and Faith
This cartoon has flowcharts comparing Science to Faith. For Faith, it is just Get an idea, Ignore contradicting evidence, and Keep idea forever.
Based on this, I am classifying String Theory (ST) under Faith. Among the ignored evidence is:
Here is a typical claim from ST guru Ed Witten:
String theory avoids the ultraviolet infinities that arise in trying to quantize gravity. It is also more predictive than conventional quantum field theory, one aspect of this being the way that it contributed to the emergence of the concept of ``supersymmetry'' of particle interactions. There are hints from the successes of supersymmetric unified theories of particle interactions that supersymmetry is relevant to elementary particles at energies close to current accelerator energies; if this is so, it will be confirmed experimentally and supersymmetry is then also likely to be important in cosmology, in connection with dark matter, baryogenesis, and/or inflation. Magnetic monopoles play an important role in the structure of string theory, and thus should certainly exist, if string theory is correct, though they may have been diluted by inflation to an unobservable level.No, ST does not avoid the infinities, and it is not predictive. Conventional quantum field theory successfully explains all of the atom smasher experiments, and ST explains none of them.
Although it is by no means obvious, this simple replacement of point-particle material constituents with strings resolves the incompatibility between quantum mechanics and general relativity (which, as currently formulated, cannot both be right). String theory thereby unravels the central Gordian knot of contemporary theoretical physics. This is a tremendous achievement, but it is only part of the reason string theory has generated such excitement.This is more nonsense. ST does not resolve any incompatibility. It has not achieved any physics at all. ST advocates like to say that it must be true because it is beautiful and consistent, but these aren't true either.