It’s that time of the month again.
This afternoon at 5 ET I’ll be doing my internet science radio gig as one of three hosts on Virtually Speaking Science. The others, btw, are Alan Boyle and Jennifer Ouellette.
My guest will by my MIT colleague Allan Adams. Allan is a physicist — a string theorist, AKA someone who works on problems that have been famously twitted as having no rea world test or validation.
That’s a misleading claim on a bunch of levels, some of which are implicated in some recent work Allan and several colleagues have done. The latest, reported in a paper in Science last summer, uses math derived from string theory that’s been applied to the study of black hole dynamics to investigate what happens as a superfluid — a frictionless fluid whose behavior is described by quantum mechanics — displays turbulence.
That’s a mouthful, to be sure. Here’s the nub: a mathematical description of one kind of physical system — a black hole — turns out to explicate the behavior of a very different one, that, as it happens, can be produced, observed and analyzed right here at home.
Think on that for a second.
This is an instance of the most …
…miraculous is the wrong word for it, so perhaps better, astonishing fact about modern science: it really, really works, and it does so through a path that mathematics opens up. We can make sense of our surroundings because of what seems to be an invention of the human mind, a system of logic rigorously expressed that can describe and evolve the relations between ideas, concepts and things in the world. But here’s the weird bit: that tool, that invention of thousands of years of human culture, does so across every more disparate, ever more encompassing domains — from the lab bench to a collapsed star, for example. Mathematics as a creation of fallible humans seems to be in some sense an intrinsic property of the universe, which is a much more banal statement than it appears, in one sense, since what it really says is that mathematical accounts do what people were trying to do with the stuff: find ways to construct arguments in forms that can be checked for accuracy and internal consistency that satisfactorily describe, say, the flight of a cannonball or the path of a planet.
So Allan and I are going to talk about all that: his recent work as an example of the unreasonable effectiveness of mathematics; about how physicists actually use math — what kind of thinking actually goes into doing this kind of work; and about why string theory, for any paucity of new prediction or unique evidence in its favor is still such a fertile field of inquiry — and what that fact tells you about how science actually advances.
Heady stuff, I know, but I, with my physics degree from the school of having things fall on my head, will keep the conversation working as a way to see into what (a) physicist does. Allan, you’ll find, is great value, that most fortunate of human who finds nothing but joy in the work he does. That’ll come through — the great pleasure of my work is to get to spend time with people who know cool stuff, find out more, and can’t stop talking about it. That’s what you’ll get in just a little while.
Tune in if you have a chance, or stop by the Second Life live studio experience, or catch it later as a podcast.
*The phrase “The unreasonable effectiveness of mathematics” was the title of an essay by Nobel laureate physicist Eugene Wigner. Highly recommended. It’s concluding thought:
The miracle of the appropriateness of the language of mathematics for the formulation of the laws of physics is a wonderful gift which we neither understand nor deserve. We should be grateful for it and hope that it will remain valid in future research and that it will extend, for better or for worse, to our pleasure, even though perhaps also to our bafflement, to wide branches of learning.
Image: Jan van Bijlert, Musical Company, before 1671.
chopper
it’s still hard to wrap your mind around the idea that a liquid with zero viscosity would show turbulence. of course, it’s ‘quantum’ turbulence which is different from the regular kind.
sparrow
I will try to tune in for at least the first part. I’ve been guilty of disparaging string theorists, so I’m curious about what they’ve been up to.
Math is strange, because it must be universal. Funny how often in scifi first-contact scenarios, proving mathematical prowess is one of the first tools of communication/validation.
Dee Loralei
Sounds really interesting. My father, the physicist, always says that God is a mathematician with a really weird sense of humor and a penchant for the absurd.
Jebediah, RBG
So the neocons were right after all – we do make reality.
schrodinger's cat
@Jebediah, RBG: No, we just interpret it.
slippy
@sparrow:
What if we meet an alien species and the FIRST thing we learn about them is they have no clue what “math” is, and use a completely different discipline to understand the universe?
I ended up at this thought mostly because I was wondering: what if our irrational numbers and mathematical paradoxes make perfect sense in some alternate form of reasoning that I can’t even imagine because I grew up thinking it was math or nothing. And I was lead to wondering about irrational numbers because of pi, and I had some of Carl Sagan’s ruminations on that number from the novel Contact in my head, and it just occurred to me what if pi is not irrational to someone else? What if it all “adds up” somehow, in a system that is not math . . . . this is a question that can’t really be answered unless someone either thinks up an alternative system to math, or we meet an alien species and see what really happens.
Either way, I continue to nurture this little idea in the hope that it will someday prove useful. And when I say “not math” I kind of think of how music is something you learn by ear, or by theory. Both approaches work. One requires a little more visceral understanding of what’s going on. It’s that visceral understanding I wonder about.
El Cid
You should write a little essay on how transformational optics brought the theoretical intrusion of 10 dimensional objects into a 3 dimensional world into play with metamaterials, forming human made surfaces capable of doing things which no natural or even engineered solids could formerly do.
The Other Chuck
@slippy: Pi is irrational in any sense where you have the notion of ratios of discrete quantities, and discrete quantities comes with having numbers. Some fractions might be repeating in some bases and not in others, but irrational is irrational in any base. Our mathematical models might not make any sense (or they’ll likely be seen as antiquated), but if we have any hope of communicating abstract concepts, math might be the only way.
Now they could have a completely different notion of numbers themselves, but that would likely make them so completely alien as to be incomprehensible at any level. Let’s hope they know how to interpret smiles and grunts.
Problem is, the physics of interstellar travel still are what they are, and we’re on the lonely sparse backwater rim of the galaxy to boot. Not betting on aliens ever finding this rock (of course that might well be a GOOD thing).
matt
I dunno. I wonder if putting our brightest young physicists to study string theory was a misuse of this resource, if the only thing they have to show for it is math that’s useful for other, more mundane physics.
It’s like Tang but without the moon landing.
Beats them all becoming quants, I guess.
Belafon
@slippy: @slippy: The only way you wouldn’t be using mathematics is if you aren’t counting. A lot of things just fall from counting – such as primes that Carl Sagan uses as the starting point of communications.
Pi is interesting to me because it is a property of the universe, unlike e (2.71828…) which is a property of numbers. As The Other Chuck says, it’s a ratio of two measured values. If the way they are measured changes, then the value changes.
Thlayli
“If you argue with math, you will lose.”
— commercial for LED light bulbs.
Baud
@Belafon:
Is that right? I thought both Pi and e had mathematical derivations as well as physical manifestations.
scav
There’s another one or two (or somewhere in-between) nubs, or at least reminders, in there. One, the mathematical description was subject-independent, which should be fairly uncontroversial, but sometimes needs to be remembered. The mathematics are an expression of a model of a process — but replicated something else. Does that mean the expressed underlying process is necessarily the same in both cases? Um, maybe, but there are damn random models that can replicate city outlines (might have been something about land use) pretty well, does that mean city boundaries (or land use) are randomly created? It’s a clue about something but needs the inevitable further research.
Then there’s the production, reproduction and prediction step. I’d call it ground-truthing in my world. This is the bit that some devotés of mathematics skip. “But it’s based on mathematics!” was a cry heard not a few days ago here. Well, goody, it works in theory. Bring me some dirt from Missouri and we’ll talk. And we’ll also be stomping over the first paragraph while we’re at it.
Mathematics is amazing and has fantastically sharp edges but it’s not magically sufficient in and by itself; there is a larger context of use, and it needs to be well-handled. See what the hedgies did with mathematics and yes, I’m afraid I tend to look hard at most economists wielding equations — they tend to disdain the ground-truthing and rely on the fidelity of their models to higher truths.
Jebediah, RBG
@The Other Chuck:
I’d say its even odds that any race advanced enough to get to us will see us as we saw Native Americans – savages getting in the way of exploiting these lovely natural resources they just “discovered.”
NotMax
Synchronicity.
Also too, mathematics: It’s a whole lot more than arithmetic.
Friend of mine (professor now, first met him when he was a wee sprat) has spent years studying the mathematics of theoretically stacking cannonballs in eleven dimensions.
Anoniminous
@The Other Chuck:
Depends on the geometry.
Yatsuno
Will there be cake for Unca Joe’s birfday?
eataTREE
God coded the Universe in Math.
MattR
@Thlayli: I love that those commercials basically call conservatives/libertarians a bunch of dumbasses for their opposition to more efficient lightbulbs.
Belafon
@Baud: You are right in that the constants tend to turn up in both locations. To me, what separates pi is it’s definition, the ratio of a circumference to it’s diameter. I imagine universes where the diameter’s measurement is different, because any region inside a circle has a “bulge” that we would see if we were to look in. Therefore, the diameter is larger, and the circumference is smaller. e is a mathematical definition: the limit as n goes to infinity of (1 + 1/n)^n is the same value.
ETA: A lot of this is us assigning importance to some values over others, but I do see a physical significance in pi that doesn’t exist for e.
nicteis
@slippy: If it “adds up” in a system, that system is math. It may of course be a corner of math of which at present humans have no inkling.
The greatest joy of doing mathematics is that it is chock full of seemingly completely independent systems of thought – complex numbers, p-adic numbers, Lie groups, Riemann manifolds, Galois groups, automorphic forms, and on and on. But as explorers drive deeper into each of these dark continents, they keep finding that the dense jungle thickets of one continent are linked by logical wormholes to the bright savannahs of another. Not only is math unreasonably effective at describing the real world; different branches of math are unreasonably effective at describing one another.
See Frenkel’s scrumptious new book “Love and Math” for a bouquet of examples.
Bring on those aliens of yours. Our intractable Goldbach conjecture will be a pillar of one of their Platonic temples, and from Princeton to Goettingen a million preprints will blossom.
Jebediah, RBG
@NotMax:
Are those cannonballs for the defense of Obama’s 11 dimensional chess board?
Belafon
@nicteis: I’m more of a fan of mathematics than a student, but I’ve started getting into Category Theory (because of computer languages like Haskell), which seems to be laying a mathematical foundation for why these branches are similar. I’m still at a newbie level, so I can’t say much more, but it’s kind of interesting. I do like the fact that you can use category theory to analyze category theory.
Anoniminous
@scav:
This
Valdivia
I have been waiting for a place to drop this at and I am really sorry to be so low-brow in a maths thread (hhis) but it made me smile on this dreary day
http://mashable.com/2013/11/19/mike-tyson-foot-locker-ad/#:eyJzIjoidCIsImkiOiJfY2h4dG5yMGdsaGM4MWZzNG91b2ZfIn0
you’re welcome
MikeJ
@eataTREE:
Or APL. Practically the same thing.
Jebediah, RBG
@nicteis:
I tried putting one of those in a ’64 3-dimensional Chrysler Newport. Did not work well at all.
Jebediah, RBG
@Yatsuno:
Who is Joe?
ETA: Oh, that Joe. I assume then it will be a big fuckin’ cake.
Violet
@Valdivia: That’s awesome. Who’s the guy burning the suits?
Roger Moore
@Belafon:
Pi is a purely mathematical definition. It’s the ratio of a circle’s radius to its diameter in Euclidean geometry, not in reality. People are prone to lose track of that because our local space time is flat enough that measurement error is more important than spacetime curvature in deviations between measured and calculated values of pi, but it’s a real distinction. IIRC, there are physical manifestations of e, but they’re much less obvious to an ordinary observer- which is exactly why e wasn’t conceive of until much later than pi.
RSA
@sparrow:
H. Beam Piper’s SF short story, “Omnilingual,” had human beings trying to figure out how to read books written 50,000 years ago by a now-dead Martian civilization. The breakthrough came when they discovered a periodic table. (Sorry if I’ve spoiled a 1950s story for anyone.) Physics and chemistry are universal, though in a different way.
RSA
@MikeJ:
This is a Deist view of the universe–does anyone program in APL any more?
MattR
@Violet: Craig Sager
(EDIT: His suits have a tumblr page)
Robert Sneddon
@Jebediah, RBG: If hypothetical aliens discover us and arrive on our doorstep then they’ve just flown past the rest of the Solar system including a couple of gas giants if they need hydrogen or most other gases, Saturn with its ice rings and moons if they want water or methane, the asteroid belt if they want rocks or metals and the comet-rich Oort cloud if they’re REALLY thirsty. Why bother coming down into an inconvenient gravity well to a planet with a thick oxidising atmosphere to get raw materials? Energy? The sun, but there are better sources around than our low-power G-type illuminator — they could chuck rubble into a black hole and get serious energy returns.
“To serve Man”? One bite of us and they die in convulsions, assuming our co-dependent biosphere doesn’t make them come out in large purple spots (presuming they don’t have large purple spots to begin with). See “War of the Worlds” for a worked example. Really I can’t think why WE hang around down here…
Valdivia
@Violet:
I have no idea, that was the only one I missed but just the ear part was enough for me (the Rodman part too!)
@MattR: thank you! now I think the add is perfect. love how good humored they all were about it
Bill Arnold
@RSA:
I was told maybe 5 years ago that a bigger-data version/variant of APL (forget the name) was popular with quants.
Jebediah, RBG
@Robert Sneddon:
Cuz it’s where all my stuff is!
Valdivia
@MattR:
those suits are just. I have no words.
my eyes.
burnspbesq
Divine inspiration is as plausible an explanation for that as any other.
MattR
@Valdivia: Imagine trying to answer questions from him while staring at one of those. Kevin Garnett couldn’t do it (that suit was ranked #4 in a top 10 compiled by Bleacher Report)
RSA
@Bill Arnold:
Cool, thanks. I was exaggerating, but I didn’t know that APL or any descendant was still popular with anyone. My last experience with it was in college back in the early 1980s, when I found it to be slow to write (elegance coming with effort) and very slow to read.
Valdivia
@MattR: I can understand why! Just wow.
Tom Levenson
@burnspbesq: Um. No it’s not. Because the universe described by the best math we have does not (as Laplace informed Napoleon) require that hypothesis.
Violet
@MattR: Thanks. Obviously I don’t watch much basketball or sports in general. No idea who he was.
SiubhanDuinne
@MattR:
I’ll see your Craig Sager and raise you Don Cherry.
tybee
@SiubhanDuinne:
dayyum. what a wardrobe.
Belafon
@Roger Moore: Looking further, I will claim to stand semi-corrected. It is a property of geometry. And it’s probably my perception of the development of geometry as a description of the physical world that influences my thinking. It is very important, as you say, to make sure to keep the pure mathematical feature of geometry in mind when using it to describe things, because it is an approximation.
mclaren
Your statement is provably false.
Please provide links to at least three (3) peer-reviewed scientific journals showing that the compactification of Calabi-Yau manifolds has been, or can ever be, tested by any scientific experiment ever performed, or which might plausibly be performed in the foreseeable future, or stand revealed as a liar.
Please provide links to any article in any peer-reviewed scientific journal showing experimental evidence for more than 4 dimensions (3 dimensions of space, 1 dimension of time), or stand revealed as a liar.
Please provide links to any experimental data from any HEP facility showing evidence for any superpartner particles, or stand revealed as a liar.
Please provide links to any experimental data proving evidence that any of the approximately 10 exp 500 theoretically possible vacua, aside from the current physically observable vacuum in our universe, can be experimentally determined to exist, or stand revealed as a liar.
Please provide evidence showing that the anthropic principle can be disconfirmed by scientific experiment, or stand revealed as a liar.
For the remainder of the case against string “theory” (so called), we outsource the issue to Peter Woit:
Source: “Not Even Wrong” blog, Peter Woit, 15 November 2013.
Woit has a regular feature on his blog called “This Week’s Hype.” On 19 October 2011, he points out:
You can find out more by reading Woit’s “This Week’s Hype” on that date. It’s the usual bullshit of the kind Tom Levenson has purveyed here today. (Hint: the “superluminal neutrinos” were junk data from an HEP experiment which has since been explained as a cable that wasn’t plugged in.)
On 18 June 2013, Woit’s “This Week’s Hype” mentions:
More bullshit, with details you can peruse by reading Woit’s column from that date. The same kind of horseshit Tom Levenson peddles here.
In the 10 December 2012 “This Week’s Hype” Woit skewers the latest bogus claims about string theory:
Turns out that the so-called “evidence” is that string theory turns out to be consistent with quantum mechanics in the limit of low energies. More obvious nonsense of the kind Tom Levenson is trying to sell us with his post today. You can find more details, as usual, by reading Woit’s column from that date.
In Woit’s “This Week’s Hype” from 5 September 2012, he remarks:
As usual, you can find the details by reading Woit’s column, The hype is, again as usual, the kind of deceptively dishonest bullshit Tom Levenson tries to scam us with in this post today.
In Woit’s 21 August 2012 “This Week’s Hype,” he discusses a New Yorker article in which the authors rashly claim “The Higgs suggests that there could be more dimensions of space-time than we previously thought,” a claim devoid of even the slightest scintilla of supporting evidence, and Woit concludes:
As always, you can find more details by reading Woit’s column — details deflating the deliberately deceptive twaddle peddled by unscrupulous individuals like Tom Levenson, in his post today.
In Woit’s 22 December 2011 “This Week’s Hype,” he notices that
As is always the case, you can find the nitty-gritty minutia in Woit’s post. He thoroughly debunks the vacuous Japanese announcement, revealing it as nothing more than the empty hype we find in Tom Levenson’s post today at Balloon-Juice.
I could go on, citing post after post after post after post of “This Week’s Hype” by Woit deflating and exposing and debunking this kind of vacuous pro-string “theory” twaddle, but why bother? Read the articles youself. Examine the evidence. Make your own decision.
Has any experiment in the entire history of science provided any evidence for string “theory” (so-called)?
Has any form of string “theory” (so-called) from M-theory to supersymmetry, made a single prediction which can be experimentally tested?
Examine the evidence.
Decide for yourself.
Which leaves us with the deliberately deceptive assertion by Tom Levenson. It’s worth examining Levenson’s claim because it’s tantamount to a lie by omission. Levenson’s claim that the well documented and thoroughly demonstrated untestability of string “theory” is “misleading” boils down to the following exercise in spectacularly mangled logic:
Because some of the mathematics developed for string “theory” (so-called, which has never made a single prediction which can be experimentally tested) can be applied to other physical situations which can be tested, this therefore somehow indicates that string “theory” (so-called, although it has made no predictions which can be disconfirmed in the laboratory) is valid.
Notice the form of this defective syllogism. Major premise: mathematics developed for one untestable theory… Minor premise: …can be used to describe an entirely different physical situation, which can be tested. Conclusion: therefore, the untestable theory is testable and scientifically valid!
Using the same defective syllogism, we can “prove” that numerology is testable and scientifically valid. Major premise: numerology converts numbers into letters, as for example someone’s name… Minor premise: converting letters into numbers and performing mathematical operations on the numbers has valid proven applications in cryptography. Conclusion: therefore numerology is testable and scientifically valid!
We can carry Tom Levenson’s grotesquely faulty logic forward into many other fields. Astrology is testable and scientifically valid. How do we know? Because the mathematics developed for predicting the position of the planets in the sky can also be used to guide space probes. Astrology uses the same type of mathematics, therefore astrology is testable and scientifically valid. Likewise, global warming denial and testable and scientifically valid. The various sorts of spurious curve-fitting used by global warming deniers can be applied usefully to other situations which are scientifically valid, such as filling in noisy or lossy data in communications systems with interference. Therefore global warming denial is testable and scientifically valid.
There comes a point when even the most dishonest and ignorant purveyor of pseudo-science should have a little reluctance to humiliate himself further.
Tom, have you no shame? At long last, sir, have you no shame?
Last, but far from least, Tom Levenson caps off his post with the gem:
Alas, Tom fails to distinguish twixt the possessive and the contractive. Pro tip: “it’s” represents the contractive form, short for “it is.” The possessive form is: “its.”
When purveying vacuous pseudoscience, Tom, you want to make sure that you first get the basic mechanics of the English language right. Otherwise, you make yourself a double laughingstock — once for the junk science, and again for the inability to pen grammatically correct fifth-grade English.
mclaren
@burnspbesq:
Utterly wrong, as usual. Our resident shit-for-brains tax avoidance lawyer predictably makes a fool of himself, failing to realize that the difference twixt divine revelation and laws of physics is that when you stop believing in a law of physics, it still works.
By contrast, when we read e.g., the Book of Revelations and try to relate it to reality, guess what?
It fails.
The Book of Revelations is bullshit.
Let’s take a look at the text of some “divine inspiration,” in this case the Book of Revelations:
This is word salad. It’s gibberish with no more connection to reality than the babbling of the Three Stooges.
By comparion, when we read in a physics textbook that F = ma, we can apply a measured force to a measured mass, and measure its acceleration. And guess what? We always find that the physics works. It corresponds to and predicts reality.
Meanwhile, the “divine inspiration” stuff in the Book of Revelations does not work. It does not correspond to reality and it does not predict reality. It’s nothing but a bunch of word salad designed to scam gullible dupes into reaching into their pockets and shelling out some cash — in this case, to the power-hungry pedophiles operating their originzed religion racket.
Or, in burnspbesq’s case, to the greed-crazed sophist operating his licensed law racket.
Jebediah, RBG
@mclaren:
Holy shit, you’re like a goldbug, but for science!
chopper
@Jebediah, RBG:
when it comes to high-energy physics, the only people more self-righteous than string theorists are ‘STRING THEORY IS WRONG!’-ists.
for the most part. my friends working in supergravity don’t catch nearly as much shit, but that’s just because it isn’t as well-known. something about multiple dimensions makes some people rip their clothes off and gibber like a gibbon.
divF
@chopper: As a mathematician (of sorts – I design numerical methods for PDE) I regret that I come down on the side of mclaren (sans the vitriol) – there is too much theory here chasing too little (in this case no) data. I have a second beef with the more pure of my colleagues (and these folks are mainly pure mathematicians, the string theory is just a fig leaf). There is a strain of revisionist thought in post-Bourbaki mathematics that mathematics has *always* been driven by pure aesthetics, and that applications always came afterwards and serendipitously. This is nonsense. Newton, Euler, Gauss, Riemann, Hilbert, von Neumann, and most of the rest of the greats were simultaneously proving theorems and trying to solve practical problems, with each activity playing off the other (alright, I’ll concede Hardy as an exception). Finally, I will have to wait to see the final tally on the superfluid turbulence application. Turbulence in all its forms have had a succession of triumphalist theories that that have turned out to be flops, with the superfluid variety being no exception.
chopper
I’ve always thought string theory to be a dead end, mostly due to the insane energies necessary to test it.
OTOH, I don’t flip my shit over that belief.
Joey Giraud
Only needed to scroll to “Unreasonable Effectiveness” and I knew it must be Levenson.
I’ve wondered for a long time if the three spacial dimensions we experience is an emergent phenomenon, since three dimensions is the number that supports energy conservative fields ( the 1/x^2 component of gravity and electric force laws )
And even longer ago I had the now-silly-seeming idea that the reason that math was so effective in describing the universe is that the universe is made up of large numbers of things.
Joey Giraud
@mclaren:
mclaren, “Not even wrong” is fightin words in academia. Your picayune complaints on Tom’s grammer indicate a real failure to understand the context here. It’s a layman’s website. And Tom didn’t really say that String Theory had been proven correct.
You’re like that crank friend of mine with a physics BA who’s developed a warp drive in his basement, except that the federal government won’t give him the rare earths to complete a prototype so he can’t show anyone.
OTOH, nice takedown of burnsy. Quite correct.
Ruckus
@chopper:
Thanks for that.
I knew there was a logical explanation to this particular line of bullshit but forgot about gibber like a gibbon.
Ruckus
@nicteis:
Not only is math unreasonably effective at describing the real world; different branches of math are unreasonably effective at describing one another.
Aren’t most just trying to prove/disprove others work or build upon something already proven? That gets one a connection by it’s very nature.
mclaren
@chopper:
Really?
I asked for any evidence from any experiment in the entire history of science showing that there are more than four dimensions. Why is asking for experimental evidence “ripping my clothes off and gibbering like a gibbon”?
When there’s very little experimental evidence for a scientific hypothesis, or when the experimental evidence is ambiguous, the scientific theory is worth discussing.
When there is absolutely zero experimental evidence over the last 350 years for a scientific hypothesis despite repeated testing, why is that scientific “theory” worth discussing?
There exist plenty of hypotheses for which zero scientific evidence exists. For example, the hypothesis that invisible unicorns in the galaxy of Andromeda are responsible for the movements of the planets in our solar system. Why would anyone think that’s a hypothesis worth discussing? There’s no possible way of testing it. It makes no predictions we can test. Why even discuss such twaddle?
String “theory” also provides no possible way of testing it, unless you can show us how to build an accelerator that generates significant collision cross-sections on the Planck length, 1.616252×10−35 meters. Hint: a cyclotron the size of our galaxy would not be big enough.
String “theory” makes no predictions we can test.
Why discuss it?
And why does asking that question involve someone who “rips their clothes off and gibber like a gibbon”?
mclaren
@divF:
But the essential problem is much bigger than that. It’s not just that there’s no experimental data to support string “theory.” The essential problem is that there are 10 exp 500 theoretical vacua. So if you crank up the Large Hadron Collider and find no sparticles, you just re-adjust the constants in your string “theory” and say, “Oh, that’s because we need higher energies.” But the problem is that we’re already at 4 TeV of the theoretical maximum 7.5 TeV maximum energy of the LHC and there’s been absolutely zero evidence of anything beyond the Standard Model — no superpartner particles, no hints of extra dimensions, nothing. Absolutely nothing.
I’ll outsource to the blog Resonaances:
Source: “A Kingdom For A Scale,” Resonaances blog, 13 August 2013.
In short, the LHC is at about 60% maximum illumination, and absolutely nothing beyond the Standard Model has been found. This does not bode well for string “theory,” but more to the point, the very nature of string “theory” with its 10 exp 500 vacua, means it isn’t really a “theory” at all in the traditional sense of the word. A testable scientific theory makes predictions which can be disconfirmed. For example, the Michael-Morley experiments tested the prediction that empty space is actually a medium with its own flux which has an effect on the propagation of light. The luminiferous ether hypothesis was tested and disconfirmed because no matter in which direction the apparatus was set up, the interference fringes never changed.
But with string “theory” (so-called), any time you rule out one energy range or one set of possible masses, the string people can simply fiddle with the constant and move to a higher energy range and larger masses. So the string people can just keep going until you run out of cyclotron. They can twiddle the constants to require energies of 100 TeV, 1000 TeV, 10,000 TeV, 10 exp 100 TeV, or more. And how do you build a collider that can generate those kinds of energies? It’s physically impossible. You can’t get energies at that scale even with colliding black holes.
So how do you test string ‘theory’? With 10 exp 500 possible vacua, it predicts anything. But a theory that predicts anything, depending on how you massage the constants, actually predicts nothing.
I’m far from the only person who has pointed that out. Trashing critics of string “theory” as people who “rip their clothes off and gibber like a gibbon” means you’re saying that the bulk of the high energy physics community falls into this category. New faculty positions for string theorists have dried up. The funding is going away. Quietly but surely, the HEP community is realizing that SUSY is just not going to yield any testable predictions, and they’re moving away from it.
We do have evidence of new physics beyond the Standard Model. The problem is that it’s not coming from the colliders. And it’s certainly not coming from calculations made by string “theorists,” because they’re not giving any testable predictions. The evidence for new physics is coming from astrophysics. Dark matter and dark energy strongly suggest that the Standard Model isn’t complete.
The problem for string “theory” is that it never predicted any of this (because it can’t predict anything we can test). A viable candidate for the “theory of everything” that unites gravity and quantum mechanics would have predicted dark matter and dark energy. It would have predicted that galaxies with very large red shifts are accelerating as they move away, rather than slowing down. String theory didn’t do that.
There are plenty of things Tom Levenson could be talking about that involve real physics, rather than untestable B.S. The latest Ice Cube south pole neutrino cascade findings with 1000 TeV energies. The latest anomaly in the angular distribution of of B0 → K*0 (→K+π-) μ+ μ- decays at the LHC. Nima Arkani-Hamed’s amplituhedron calculation method for cross-sections. Lots of things that are real physics, involving real calculations that can be tested, and real measurements that can be compared against real experimental results.
But string theory gives us nothing. Nothing we can test.
How do you salvage a “theory” like that?
mclaren
@sparrow:
Unfortunately incorrect. Depending on your axioms, your math can totally contradict mine. See Paul Cohen’s work from 1963 in which he proved that neither the axiom of choice nor the continuum hypothesis can be proved from Zermelo-Frankel Theorem. This means that depending on your choice of axioms, you can generate entirely incommensurable but within their own frameworks correct systems of mathematics.
I would also commend to you the Banach-Tarsky paradox, which shows that even though a theorem may be mathematically provably correct, it can flagrantly contradict observed reality. Unless, that is, you want to show us how to disassemble (say) the moon into 10 exp 70 pieces and then reassemble into an object twice the size without any empty space inside. That’s not physically possible. But the Banach-Tarsky theorem says you can do it, mathematically.
In the real world, mathematics sometimes proves unreasonably effective — astronomy, physics, chemistry, et al. But mathematics also sometimes blows up badly and gives us results which grossly contradict observed reality. Examples include financial modeling, DSGE economic models, and the long history of failed efforts to make political or sociological predictions based on mathematical models.
Mathematics is not some magic wand you can wave and get reliable predictions out of. It works in some areas, where the systems are simple enough that they can modeled by linear models. For other systems, like politics or economics or the weather, the systems are so complex that linear models prove inadequate. Mathematics offers little help there.
In fact, there’s a good case to be made that the entire global financial meltdown of 2008 was due to the arrogant and unwarranted belief by economists and financial quants in the allegedly “unreasonable effectiveness of mathematics” when applied to capital markets, economics, and human behavior. As they discovered to their horror, that’s just not the case.
Fred
Gosh, I could have done with a bit less exuberance of how wild and crazy fun it all is and just a taste of the subject you tipped your hat at. No doubt most of it will go over my head but I’m always game to glean what I can. Black holes are always fun to think about.
chopper
@mclaren:
there’s “asking for evidence” and there’s “SHOW ME EVIDENCE OR BE REVEALED AS A LIAR! DISHONEST BULLSHIT!!!”.
one of the biggest problems gibbering gibbons have is that they can’t even recognize their own gibbering. they think they’re being ‘reasonable’.
chopper
@mclaren:
apparently, the physics world disagrees. a nice segment of it thinks it’s worth discussing.
as i said, i think ST is a dead end. but i don’t get to tell physicists and scientific laymen what they should and shouldn’t be discussing. and neither do you, as much as that must drive you insane with rage.