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Author Topic:   String! Theory! What is it good for ?!?
Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 1 of 107 (535076)
11-12-2009 6:42 PM


M-theory is the current best candidate for a TOE ("Theory of Everything") in science. It's intended to provide an overriding explanation of all 4 fundamental forces; the Standard Model of Quantum Mechanics only covers 3 of them, leaving out gravity. General Relativity successfully explains gravity in most circumstances, but breaks down or becomes "non-renormalizable" on the quantum level when very high energy levels are involved. Or something like that ...
The M in M-theory stands for whatever you want it to. Current favored candidates are Membranes, Matrix, and Magic. *shrugs* It's a working reconciliation of 4 to 6 previous superstring theories, depending how you count. These tend to turn into one another when you switch the numerator and denominator of various equations, and involve 6 more dimensions than we like to use to describe spacetime in more primitive theories. But they seem to disagree on which dimensions are what? So M-theory sorts them out by positing a total of 11 dimensions, the 4 we recognize as spacetime and another 7 altogether that are used to describe quantum phenomena only. Or something like that ...
This tends to read like a detailed specification for Wheeler's "Many Worlds" speculation. That is, there are many adjacent "branes" or sub-universes which have an indirect effect on our own. Thus, gravity is such a weak force because most of the gravitons are leaking into other branes. Conversely, the universe-binding extra gravity we tend to attribute to "dark matter" is actually caused by gravitons leaking in from other branes. Or something like that ...
There's a growing tendency for apparently reputable people to describe this whole line of thinking as "pseudo-science". This is a loaded term in academia, so let's be careful how we define it. For purposes of this context, pseudo-science is a body of thought that uses scientific terminology and builds on existing mathematics and cosmology but doesn't conform to the scientific method. The normal charge is that it doesn't make any useful predictions, or is unfalsifiable. Real science, by contrast, can be tested and either supported or else proven wrong. Or something like that ...
The term pseudo-science is also very commonly used to describe what is actually "junk science", claims that have already been falsified and/or are merely using scietific terminology for psychological reasons, as a form of misdirection or charlatanry. One reason this use may be valid is in cases like Spiritualism or Geller ESP, where the claim is advanced that the presence of skeptics has a real effect on the experiment. "You have to have faith!" In other words, testing it rigorously is what keeps it from working? Which, even if it were true, would be unfalsifiable. Or something like that ...
This secondary usage is what makes a real pejorative out of the term. But we are going to limit the context in this discussion. No one is claiming string theory is the same class of thing as astrology. They may, however, be claiming that it is the same kind of thing as transcendental theology. Or something like that ...
So, let's cut to the chase. What predictions, if any, does M-theory make that could eventually be tested, and by what methods? What results, if any, would falsify the theory, prove it wrong, send us back to the drawing board?
Or something like that. Is It Science?

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 3 of 107 (535087)
11-12-2009 7:37 PM


Absolutely Nothing
Here's a link to the brane this discussion leaked in from
Precognition Causality Quantum Theory and Mysticism
It's a wonderful review of various kinds of junk science and magical thinking like telepathic dogs and Iraqi bomb detectors. Anyway, in the midst of the row, Izanagi jumps in and says So what? String theory is pseudo-science too! Message 101 Note that this is really a confusion as to which kind of pseudo-science is being discussed in the other thread, by the way.
Onifre catches the ball and goes for a line drive. Message 115
That's a load of crap
I shout to him from the sidelines Hey look out! That path isn't clear! Message 234
But cavediver insists I go back to the water-bucket and stop worrying, the guys blocking him don't even deserve to be on the field. Message 235
idiots such as Woit and Smolin who both have immense and unwarranted axes to grind
So anyway, I want to know how the trick works. What's a prediction, what's falsifiability, what is M-theory in this context? I'm learning quite a bit just by studying up on what pseudo-science is.

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 6 of 107 (535102)
11-12-2009 8:57 PM
Reply to: Message 3 by Iblis
11-12-2009 7:37 PM


Re: Absolutely Nothing
Here's something nice from a deliciously inflammatory wiki called the Conservapedia that puts the claim in a nutshell:
The term pseudoscience is also often applied to theories which are falsifiable and have in fact been falsified and discarded. Phrenology predicted that psychological traits could be inferred from the shape of the skull, but no actual link was ever found. Various astrological theories predicted regular planetary effects on the earth and human health, but testing those failed.
The existence of God is thus not considered scientific theory, as no test can possibly be conceived which categorically disproves His existence. The same is the case for string theory, which is a mathematical unification of scientific theory, but makes no predictions. Such things fall outside the realm of science.
http://conservapedia.com/Pseudoscience#Disproven_science
This seems to be too strong to me, to say the least, for reasons I will go into in a moment. But first, it was interesting to learn that this business of falsifiability seems to have been worked up by a philosopher named Karl Popper.
Logically, no number of positive outcomes at the level of experimental testing can confirm a scientific theory, but a single counterexample is logically decisive: it shows the theory, from which the implication is derived, to be false. Popper's account of the logical asymmetry between verification and falsifiability lies at the heart of his philosophy of science. It also inspired him to take falsifiability as his criterion of demarcation between what is and is not genuinely scientific: a theory should be considered scientific if and only if it is falsifiable. This led him to attack the claims of both psychoanalysis and contemporary Marxism to scientific status, on the basis that the theories enshrined by them are not falsifiable. Popper also wrote extensively against the famous Copenhagen interpretation of quantum mechanics. He strongly disagreed with Niels Bohr's instrumentalism and supported Albert Einstein's realist approach to scientific theories about the universe.
Karl Popper - Wikipedia
Popper also originally classified evolution as a pseudo-science on these terms, but he later stepped away from this position.
the doctrine of natural selection is a most successful metaphysical research programme. It raises detailed problems in many fields, and it tells us what we would expect of an acceptable solution of these problems. I still believe that natural selection works in this way as a research programme. Nevertheless, I have changed my mind about the testability and logical status of the theory of natural selection; and I am glad to have an opportunity to make a recantation.
Karl Popper - Wikipedia
It's important to note that Popper and the principle of falsifiability in general are directly opposed to speculations as to what might be "most likely to be true."
Popper held that it is the least likely, or most easily falsifiable, or simplest theory (attributes which he all identified as the same thing) that explains known facts that one should rationally prefer. His opposition to positivism, which held that it is the theory most likely to be true that one should prefer, here becomes very apparent. It is impossible, Popper argues, to ensure a theory to be true (but not fatal, since even false theories may have true consequence); it is more important that they can be eliminated and corrected as easily as possible if false.
Karl Popper - Wikipedia
Anyway, back to the point. The main objection to string theory, unlike transcendental theology or anti-Geller skeptic waves, is not that it is in principle unfalsifiable; but rather that in practice, it would be too difficult or expensive to test it at our imaginable level of technology.
Is string theory predictive?
String theory as a theory of everything has been criticized as unscientific because it is so difficult to test by experiments. The controversy concerns two properties:
1. It is widely believed that any theory of quantum gravity would require extremely high energies to probe directly, higher by orders of magnitude than those that current experiments such as the Large Hadron Collider[28] can reach.
2. String theory as it is currently understood has a huge number of equally possible solutions, called string vacua[29] and these vacua might be sufficiently diverse to explain almost any phenomena we might observe at lower energies.
If these properties are true, string theory as a theory of everything would have little or no predictive power for low energy particle physics experiments.[30][31] Because the theory is so difficult to test, some theoretical physicists have asked if it can even be called a scientific theory. Notable critics include Peter Woit, Lee Smolin, Philip Warren Anderson[32], Sheldon Glashow[33], Lawrence Krauss[34], and Carlo Rovelli.[35]
All string theory models are quantum mechanical, Lorentz invariant, unitary, and contain Einstein's General Relativity as a low energy limit.[36] So to falsify string theory, it suffices to falsify quantum mechanics, Lorentz invariance, or general relativity. Therefore string theory is falsifiable and meets the definition of scientific theory according to the Popperian criterion. However, to constitute a convincing potential verification of string theory, a prediction should be specific to it, not shared by any quantum field theory model or by General Relativity.
One such unique prediction is string harmonics: at sufficiently high energiesprobably near the quantum gravity scalethe string-like nature of particles would become obvious. There should be heavier copies of all particles corresponding to higher vibrational states of the string. But it is not clear how high these energies are. In the most likely case, they would be 1015 times higher than those accessible in the newest particle accelerator, the LHC, making this prediction impossible to test with a particle accelerator in the foreseeable future.
String theory - Wikipedia
This doesn't seem like a valid argument at all, to me? I mean, space shuttles and Hubble telescopes and so forth were prohibitively expensive at the time Einstein was writing, but that was only a temporary problem.

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 7 of 107 (535105)
11-12-2009 9:09 PM
Reply to: Message 5 by onifre
11-12-2009 8:47 PM


prediction
What I meant was that the higher dimensional equations in String Theory predicts gravity.
Yep, that. There's a jargon problem there, I tried to describe it as trivial and cavediver slapped me down, but I'm still missing something. Here's this bit again from the wiki
All string theory models are quantum mechanical, Lorentz invariant, unitary, and contain Einstein's General Relativity as a low energy limit.[36] So to falsify string theory, it suffices to falsify quantum mechanics, Lorentz invariance, or general relativity. Therefore string theory is falsifiable and meets the definition of scientific theory according to the Popperian criterion. However, to constitute a convincing potential verification of string theory, a prediction should be specific to it, not shared by any quantum field theory model or by General Relativity.
String theory - Wikipedia
This seems to touch on what I'm trying to point at here. And it gets even worse if you try to interpret the word "predict" as plain English. If I here now, in 2009, predict that Sir Isaac Newton will discover gravity in 1687, well, I'm some sort of loon. If I already have a copy of tomorrow's paper from my buddy at the press, and tell you what it says on page 1, I'm a charlatan. If the prediction I'm making is something that is already known, there isn't any independent value to my soothsaying powers.
"The Flying Spaghetti Monster uses his massive suck-power to hold things onto planets. He uses larger tentacles, which have more suck-power, for larger planets, and smaller ones for smaller planets. In practice we find that more massive objects attract to a greater extent than smaller ones. Therefore the FSM is not pseudo-science, because it has real predictive power."
(NOT)

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 8 of 107 (535112)
11-12-2009 10:09 PM
Reply to: Message 5 by onifre
11-12-2009 8:47 PM


nuh UNH!
String theory predicts that there is something inside quarks (roughly speaking) - as there was something inside the atom, nucleus, etc.
This is totally new to me, and I've been reading for hours. I thought string theory predicted that particles or waveforms or whatever they are like quarks, which we like to think of as dimensionaless points, are actually one-dimensional lines; and that some of them have ends that are joined and therefore aren't bound to particular branes, like gravitons, while others like photons have loose ends that make them stay in the universe where they are.
In fact, I'm pretty sure quarks do NOT have something smaller inside them. I would like them to, I would like a down quark to have a W boson hidden inside it which it emits to turn it into an up quark. But I don't see how it could, considering a W boson is about 100 times as massive as a proton. And then I would like the W boson to be composed of an electron and an antineutrino, but it isn't even though that's what it decays to.
Waveforms simply don't fit this characterization. When we split a photon, we don't get two half-photons or photon components or whatever. We get two photons! This is what makes them waveforms.
Edited by Iblis, : sign error

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 9 of 107 (535120)
11-12-2009 11:25 PM
Reply to: Message 4 by hooah212002
11-12-2009 8:16 PM


two cents
If I may, I would like to give my .02 on this.
Yes please do! Everyone with ideas about superstrings should jump in here so we can sort them out and see which ideas are more or less true or useful.
I personally would NOT classify string theory as pseudo science
Yes yes, but isn't it better to have a clear well-delimited definition and then see whether it fits the definition or not? I personally would like some ice cream.
When i think of pseudo science, I think of ID and creation: crap that is pressed on as fact or legitimate study, when it is based on bullshit.
That's really junk science though. I suppose it can fit in under the second definition, like when science proves that the earth isn't young and some "creation scientist" goes through each proof systematically adding intentional unverifiables like miraculous drying-in-liquid properties to holy floodwater or diabolical bone-creation campaigns.
But it's not that useful in this case, there is a middle ground between junk science and real science which includes things like psychoanalysis, a real system which does real things but is demonstrably non-scientific because it continues to work the same way even as underlying constructs like our understanding of brain physiology and our interpretation of childhood development change from year to year. It doesn't matter whether you rely on complexes, archetypes or engrams, if you listen to someone's problems and then parrot them back to them in "scientific" language, it helps them feel better!
In the same way, a TOE could be very useful, in that it resolved a number of nagging mathematical problems with our description of the universe, without being real science. In such a case, it would still be better to keep working on the problem until you found an answer that was scientific, testable, falsifiable, because such an answer would be likely to be categorically much more useful. In psychology an example might be our continuing study of brain chemistry, which seems to be producing better and better pharmaceutical solutions to problems that used to require a person to get their psychoanalysis in special rooms, wearing special jackets.
as it is well known to be a hypothesis, not pressed to be an actual theory ... well known to NOT be able to be studied/tested properly so as to formulate a working theory for it......YET.
I'm not sure I understand these statements. I have read that M-theory is "incomplete" but I don't know if I know what that means yet. Could you give some more detail?
Such a collision could happen at CERN’s Large Hadron Collider (LHC), which will become operational next year ... Hewett, Lillie and Rizzo solved complex equations to determine if our universe has 10, 11, or more dimensions perhaps too many dimensions to be explained by critical string theory.
Yes, this is the sort of thing we should be peppering this thread with. Here's another one from the same source.
A stau particle, however, is easier to produce and should be semi-stable, lasting as long as a minute. And it should leave a signature track unexplainable by any of the already-observed particles as it streaks across the LHC’s detectors.
It would be the smoking gun for our stringy models, Vafa said.
http://www.physorg.com/news177262216.html
There still seems to be some doubt here though. Here, look at this language from the same article
there is also a less likely possibility that a semi-stable neutral particle will be generated. If the particle proves neutral, it won’t manifest itself in a way that the LHC’s detectors would see
And this from your link
if so called micro-black holes, which are smaller than the nucleus of an atom, exist
So on the one hand, if we find the right number of dimensions via the theoretical black holes, or if we manage to see the stau, then we will have what? failed to falsify M-theory, yes?
But if we don't find them, we won't have falsified it either, because maybe micro-black holes don't exist after all, or maybe a semi-stable whatsit got generated. This sounds like neither result really proves or even supports anything then, doesn't it?

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 13 of 107 (535128)
11-13-2009 2:13 AM
Reply to: Message 10 by slevesque
11-13-2009 1:29 AM


cosmological constant
Warning: Big Dope gives unneeded history of Einstein's biggest blunder in this post rather than detecting the correct Epic Fail, see two posts down for details
Thanks for your idea!
Didn't string theory predict that the cosmological constant would be negative or null, and so that the expansion of the universe would be have a negative acceleration or be constant ? And then when they found out in 1998 that it was actually accelerating, they just reworked out the theory and made it fit the new data.
I mean, if I remember this correctly, this is pretty much the definition of an epic failed prediction ...
Nope, sorry, no offense, but this reads like an urban legend in its birth throes. I e it's a garble / composite of some real ideas relating to the history of theory in the Big Bang and Inflation, but misattributed and otherwise smudged together in various ways.
What happened was, Einstein (the guy, not his math) liked to assume a steady-state universe, one which neither begins nor ends within a range of observability. His equations, on the other hand, actually left the matter open, and a Russian named Friedmann did the work necessary to show that it might very well be expanding. Einstein at this point developed a number called the Cosmological Constant, which he set to 0, to show his preference for not expanding or contracting. WIdespread criticism and debate ensued, in which the most telling point is that in a case where a number may conceivably be anything negative or positive, any particular singular point like "0" is going to be infinitely unlikely.
That part of the debate came to an end in 1929 when Hubble (the dude, not the space telescope) finished the work necessary to show that the universe was actually expanding, by means of consistent doppler red-shift at greater and greater distances. Thus Einstein (but not his math!) was shown to be wrong, incorrect, having a preference not corresponding to what the actual results came out to be.
A generation or two of infighting went by, and in the meantime the original Big Bang theory, which said that if it's been expanding it was once very compact and sort of "exploded" into existence, had been refined into Inflation, which says that yeah it was very compact but it didn't exactly explode, it sort of "whooshed" out suddenly instead. The prediction involved in this theory was that spacetime was going to continue to be seen as relatively homgenous over distances so great as to make the areas involved causally unrelated, and in particular that it was going to be seen as relatively flat, not curved inward or outward even over vast vast distances.
What happened starting in 1989 was that the COBE and successor programs like WMAP generated tremendous amounts of data that overwhelmingly supported, and continue to support, this prediction of general flatness and homogenity.
Note that this story has "no strings attached"
Edited by Iblis, : Epic Fail

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 14 of 107 (535130)
11-13-2009 2:48 AM
Reply to: Message 12 by AnswersInGenitals
11-13-2009 1:55 AM


Professor Popper pooped a peck of pickled Plancks
LHC is not genuinely scientific
I would go the other way with this argument and say that a genuine scientific theory is actually better when it has been falsified, because then we know what its limits are! Imagine a map that you think is reliable, but in reality it sticks Australia down near where Antarctica actually is and depicts various sources of food and water that aren't actually there. Then imagine a map that has specific areas on it that are known to be unreliable, undocumented, and these places are marked with some sort of warning like a dragon. Which map would you rather have?
Newtonian mechanics are quite good enough to use if you are building a barn or something. You don't need relativity for that! The "flat earth" theory is perfectly fine for this purpose, also. You will find that gravity is constant on both sides of the barn if you use a level in the middle. But it's good to know that if you want to get to China, or Andromeda, there's a point where your maths are going to need correcting.
relativistic quantum field theory or general relativity, two theories that have yet to be falsified
They have been falsified though, haven't they? Isn't that the point of a TOE? Relativity doesn't work right at extremely low distances at extremely high energy levels. These are its limits, now we know them, we can be even more confident because we understand the theory and its scope instead of just hoping it is universal.

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 15 of 107 (535134)
11-13-2009 3:39 AM
Reply to: Message 10 by slevesque
11-13-2009 1:29 AM


NM, I'm a Big Dope
I've found the original for this business about quantum math and the cosmological constant now, it's not as smudged as I thought but you still have it kind of backwards.
Observations announced in 1998 of distance—redshift relation for Type Ia supernovae[3][4] indicated that the expansion of the universe is accelerating. When combined with measurements of the cosmic microwave background radiation these implied a value of \Omega_{\Lambda} \simeq 0.7,[5] a result which has been supported and refined by more recent measurements. There are other possible causes of an accelerating universe, such as quintessence, but the cosmological constant is in most respects the most economical solution. Thus, the current standard model of cosmology, the Lambda-CDM model, includes the cosmological constant, which is measured to be on the order of 10−35 s−2, or 10−47 GeV4, or 10−29 g/cm3,[6] or about 10−120 in reduced Planck units.
Cosmological constant problem
A major outstanding problem is that most quantum field theories predict a huge cosmological constant from the energy of the quantum vacuum.
This conclusion follows from dimensional analysis and effective field theory. If the universe is described by an effective local quantum field theory down to the Planck scale, then we would expect a cosmological constant of the order of M_{\rm pl}^4. As noted above, the measured cosmological constant is smaller than this by a factor of 10-120. This discrepancy has been termed "the worst theoretical prediction in the history of physics!"[7]
Some supersymmetric theories require a cosmological constant that is exactly zero, which further complicates things. This is the cosmological constant problem, the worst problem of fine-tuning in physics: there is no known natural way to derive the tiny cosmological constant used in cosmology from particle physics.
Cosmological constant - Wikipedia
Note that this still isn't string theory, it's field theory on the one hand and supersymmetry on the other. And they never seem to imply a negative result, but rather either a zero result, as you stated, or else on the other hand a much larger result than what we actually observe.
Sorry about the long rehash of big bang/big swoosh stuff, the language you were using really seriously reminded me of that. Here, this is from the same link
Since it no longer seemed to be needed, Einstein called it the '"biggest blunder" of his life, and abandoned the cosmological constant. However,
See what I mean? Anyway I would draw everyone's attention to the entirety of that wiki page, it touches on several things like fine-tuning that seem to be going hot and heavy in the forum lately.

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 21 of 107 (535209)
11-13-2009 6:26 PM
Reply to: Message 19 by slevesque
11-13-2009 3:21 PM


Re: Yes, that's science
Yeah, I still can't find it. Don't get me wrong, supersymmetry, symmetry breaking, and field theory are all components of superstring just like general relativity and Lorentz invariance are; so it's very likely that one of the people in such an argument would be a string theorist.
I would love to find some actual quotes though.

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 23 of 107 (535259)
11-14-2009 5:34 AM
Reply to: Message 22 by slevesque
11-14-2009 2:01 AM


Re: Yes, that's science
Ok, I'm getting closer to it. First off, here's this from the San Francisco chronicle
String theorists and their foes can't even agree on what constitutes success or failure. For example, the most unexpected and counterintuitive discovery of recent science occurred in the 1990s, when astrophysicists at Berkeley and elsewhere realized the universe is expanding faster with time. The apparent reason: a mysterious dark energy pervades space and drives the accelerated expansion.
Critics mock superstringers because their so-called theory of everything failed to predict this colossal discovery. String theorists fire back that no one else predicted it, either
'Theory of everything' tying researchers up in knots
Sound familar? Honestly, though, this sort of development strikes me as good evidence that superstring is not a pseudo-science, particularly in the hoax sense. Why? Because if it were, with the content it has, someone would have been able to throw together a provisional coup of an interpretation almost immediately.
Don't believe me? Fine, I will do it. Dark energy is energy that leaks in from other branes, just as "dark matter" is actually gravity that leaks in from other branes. The objection that we don't have any missing energy to correspond to the energy that would be leaking out of our brane is just as simple; energy, like photons, is bound to stable branes, unlike gravitons, which are looped and have no "loose ends" to lock them inside.
How is the energy getting out of those other branes into ours, then? Simple. There are a huge number of different universes in M-theory, some of which are similar to ours and some of which are wildly different. As the "fine-tuning" argument has demonstrated, a lot of those universes with even mildly different dimensionless constants, wouldn't last 3 minutes! Once they collapse, their constituent energy is no longer bound, and migrates whichever direction entropy happens to take it. Eventually it tends to settle in more long-term universes like our own.
"Oh dear," says God, "I hadn't thought of that," and promptly vanished in a puff of logic.
"Oh, that was easy," says Man, and for an encore goes on to prove that black is white and gets himself killed on the next zebra crossing.
--Douglas Addams
Edited by Iblis, : brane phart

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 24 of 107 (535263)
11-14-2009 6:49 AM
Reply to: Message 22 by slevesque
11-14-2009 2:01 AM


Re: Yes, that's science
Now on to the goodies. First up is Richard Feynmann, Nobel Laureate in Physics and coiner of the "cargo cult science" pejorative
Shortly before his death, Feynman criticized string theory in an interview: "I don't like that they're not calculating anything," he said. "I don't like that they don't check their ideas. I don't like that for anything that disagrees with an experiment, they cook up an explanationa fix-up to say, 'Well, it still might be true.'"
Richard Feynman - Wikipedia
He died in 1988, so he isn't talking specifically about dark energy, but he gets quoted a lot in this argument so he well may be what you remember reading.
There are plenty of other candidates, though. Here's a snap of Robert Laughlin, another Nobel in Physics, from the Guardian
An unprovable theory that talks of unseeable parallel universes and 10-dimensional space has proved too much for some physicists. 'Quasi-theology' and 'post-modern' have been among the most polite terms used; 'bogus' and 'nonsense' among the less forgiving.
'Far from a wonderful technological hope for a greater tomorrow, string theory is the tragic consequence of an obsolete belief system,' said Stanford University's Robert Laughlin, winner of the 1998 Nobel prize for physics.
For a theory that purports to explain the entire structure of the universe, such a high-level attack is very serious.
String theory: Is it science's ultimate dead end? | Science | The Guardian
He won his in 1998 and is still alive and publishing.
Edited by Iblis, : coynte

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Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 30 of 107 (535327)
11-14-2009 7:38 PM
Reply to: Message 26 by cavediver
11-14-2009 1:42 PM


Re: Yes, that's science
Who gives a crap about what Laughlin thinks? His field is condensed matter physics. He's so lost that he thinks that he's qualified to theorise about black holes
Maybe I don't have a good idea of what "condensed matter physics" is. Maybe that sounds to me like exactly the sort of thing that would make one an expert on black holes. (They are made out of condensed matter, ain't they?) Maybe a bit more information about the distinction is in order?
(and why they don't exist :rolleyes
Yeah he's a real hoot!
George and I made a very plausible case that general relativity, as we have observed it experimentally, could be perfectly true, and yet fail to describe a black hole event horizon properly, said Laughlin. What would allow this to happen is failure of the relativity principle on very short-length scales.
His and Chapline’s model, he argues, fixes violations of quantum mechanicssuch as information loss and the freezing of time at a black hole’s event horizon in traditional black hole models. Laughlin notes that the argument may offend his peers, but that they have no valid criticism of his and his partner’s arguments. He insists their redefinition is correct.
The point is that there is no way to tell one way or the other right now, he said. If there were, there would be no controversy.
http://seedmagazine.com/...e/what_if_black_holes_didnt_exist
So, should we just "teach the controversy"?
Anyway, he's fun to read regardless
But skeptics suggest it's the latest sign of how string theorists, sometimes called "superstringers," try to colorfully camouflage the theory's flaws, like "a 50-year-old woman wearing way too much lipstick," jokes Robert B. Laughlin, a Nobel Prize-winning physicist at Stanford. "People have been changing string theory in wild ways because it has never worked."
Already, the split over string theory has caused tensions at some of the nation's university physics departments. "The physics department at Stanford effectively fissioned over this issue," said Laughlin, now on sabbatical in South Korea. "I think string theory is textbook 'post-modernism' fueled by irresponsible expenditures of money."
'Theory of everything' tying researchers up in knots
Here's some more
"If Einstein were alive today, he would be horrified at this state of affairs. He would upbraid the profession for allowing this mess to develop and fly into a blind rage over the transformation of his beautiful creations into ideologies and the resulting proliferation of logical inconsistencies. Einstein was an artist and a scholar but above all he was a revolutionary. His approach to physics might be summarized as hypothesizing minimally. Never arguing with experiment, demanding total logical consistency, and mistrusting unsubstantiated beliefs. The unsubstantial belief of his day was ether, or more precisely the nave version of ether that preceded relativity. The unsubstantiated belief of our day is relativity itself. It would be perfectly in character for him to reexamine the facts, toss them over in his mind, and conclude that his beloved principle of relativity was not fundamental at all but emergent-a collective property of the matter constituting space-time that becomes increasingly exact at long length scales but fails at short ones. This is a different idea from his original one but something fully compatible with it logically, and even more exciting and potentially important. It would mean that the fabric of space-time was not simply the stage on which life played out but an organizational phenomenon, and that there might be something beyond."
http://physicsmathforums.com/showthread.php?t=2722
Making speeches isn't really the same kind of thing as doing experiments and observing results and modifying your hypothesis to agree with the results and doing more experiments and so on though, is it?
Now Dick is another matter
Did you know him personally?

This message is a reply to:
 Message 26 by cavediver, posted 11-14-2009 1:42 PM cavediver has replied

Replies to this message:
 Message 31 by Straggler, posted 11-14-2009 8:47 PM Iblis has not replied
 Message 32 by cavediver, posted 11-15-2009 4:32 AM Iblis has replied

  
Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 39 of 107 (535373)
11-15-2009 9:05 AM
Reply to: Message 38 by cavediver
11-15-2009 7:24 AM


prediction again
a dig at Iblis
Yep, you beat me to it. I'm going to go ahead and scribe a chunk of my imagined posts anyway, for continuity's sake
And then, low and behold, Superstring Theory turns up, and goes "hey, guess what? My low-energy sector IS Sugra!!!" Suddenly everyone who had been working on Sugra, and ignoring String Theory, goes mad. Here was possibly the missing framework whose absence caused Sugra to epically fail. And not only that, it is an explanative framework that tells us why we have Sugra in the first place, where-as Sugra just shrugs and says - this is how it is.
So what we are really saying then is that superstring predicts supergravity? Oh, never mind then, that's fine. Cancel this thread
No seriously, yes that's a much more compelling story than thinking it's similar to saying "L. Ron Hubbard predicted that in 1066 William the Conqueror would permanently pidginize the English language." But can we walk through the fundamental differences between this and the parody FSM prediction I posted?
Supergravity still came before superstring. Why are we certain that the string gurus weren't already aware of this math and specifically concocting their remarkably flexible theory to include it?
This may sound needlessly paranoid, and, well, it is. But I once read an awesomely wrong variable-c and recent-expansion non-theory from some creative-scientist that asserted that one of the people involved in Inflation had a dad that was a radio engineer, and therefore he could have "heard" the CMB and kept it a secret and conspired with his godless sodomite buddies around the world to bury an implication of it in their big lie which could then be conveniently "discovered" later.
There's something suspicious to the non-thinker about "predicting" things that are already known. Let's beat them to death.
No He died just before I arrived at Cambridge
I'm sorry to hear that. I only ask because we have heard more than one troll claim or imply that you "didn't know Dick." And I was hoping to put the lie to that
I think you'll find that Popper is not such a hero in the world of theoretical physics. And he never could quite handle the essence of quantum mechanics and the methodology behind the development of QCD and similar theories...
ABE: but this is for yet another thread
No way! Anything that helps us to understand pseudo-science, the quasi-theology of falsifiability, and its relation to quantum physics and relativity belongs right here where we can bang at it! You just like making people start threads for you, don't you? It's your way of pwning them
Anyway, back to the point ...
It's like hunting for a ten dollar bill, that you thought you'd placed in a coat in a wardrobe, and in the process you find that the wardrobe leads you into the inner-vault of Fort Knox
It's really more like hunting for a ten-dollar bill, not finding it, going ahead and taking that tedious low-paying job you had hoped to avoid in that exotic restaraunt you can't stand, and eventually getting tipped ten dollars by someone who also helps you get your dream-job that you really wanted at the LHC.
Edited by Iblis, : spling

This message is a reply to:
 Message 38 by cavediver, posted 11-15-2009 7:24 AM cavediver has replied

Replies to this message:
 Message 40 by cavediver, posted 11-15-2009 9:25 AM Iblis has not replied

  
Iblis
Member (Idle past 3895 days)
Posts: 663
Joined: 11-17-2005


Message 42 of 107 (535474)
11-16-2009 7:55 AM
Reply to: Message 27 by cavediver
11-14-2009 4:36 PM


awesomer
This is actually the post I have gotten the biggest kick out of so far in this thread
cavediver writes:
Because string theory has been viewed as unfalsifiable for this very reason: it can adapt to anything.
What is reality? - There are several of us who believe that our reality is just one infinitesimal part of a Grand Ensemble - an ensemble that makes the multiverse just our local backyard. This by necessity will involve a theory with an ability to produce an infinitude of possible realities. The fact that M-theory seems to be doing this is exactly what we expected. *If* this is how reality is built, then I guess you're suggesting that we should abandon research in the correct direction, and go play with some wrong theories that you will find more philosophically satisfying. No thanks. I don't give a shit about the philosophy. As a scientist, I'm trying to understand the nature of reality. If M-theory has something to do with it, great. If it doesn't, great.
Yeah! That's the spirit! Screw "wanting" the answer to be something and "trying to prove" it, let's find out what the real answer really is and DAMN THE TORPEDOES !!!

This message is a reply to:
 Message 27 by cavediver, posted 11-14-2009 4:36 PM cavediver has not replied

  
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