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String Theory Tested, Fails Black Hole Predictions
eldavojohn writes "Back in 2006 there was a lot of talk of testing String Theory. Well, today CERN has released a statement for the Compact Muon Solenoid Experiment. The short of it is simply that as far as they could tell, 'No experimental evidence for microscopic black holes has been found.' The long statement indicates that since the highly precise CMS detector found no spray of sub-atomic particles of normal matter while LHC smashed particles together, the hypothesis by String Theory that micro black holes would be formed and quickly evaporated in this experiment was incorrect. These tests have given the team confidence to say that they can exclude a 'variety of theoretical models' for the cases of black holes with a mass of 3.5-4.5 TeV (1012 electron volts). Not Even Wrong points us to the arxiv prepublication for those of you well versed in Greek. While you may not be able to run around claiming that String Theory is dead and disproved, evidently there are some adjustments that need to be made."
StringFail
When the foot seeks the place of the head, the line is crossed. Know your place. Keep your place. Be a shoe.
Simple. The Creator obviously didn't NULL-terminate. Hence his strings have no black hole at the end.
and failed, right here, right now on Slashdot.
I hope the hype ends now.
How can we be sure that the black holes were not created? String theory posits that there exist physical dimensions outside of our 4 dimensional universe, in fact that these are part and parcel of our universe. However, given our tools are all limited to 4 dimensions, it makes sense that there could be phenomena that is unobservable in our universe yet occurring in those other unexperienceable dimensions.
I agree with the summary, this isn't the defeat of String Theory. It is a chance to refine and improve it.
Any day now a new string theory will "predict" that we won't find any microscopic black holes. String theory's main strength is in predicting the results of experiments that have already been done. It's just predicitng anything we don't know yet that it has trouble with.
One day, Bob the Scientist was puffing on some buddha. He smoked and smoked, and smoked some more. Suddenly, Bob the scientist looked down: the lines between the tiles on the floor started to wiggle this way and that, giving the tiles the impression that they were vibrating. Bob the Scientist blinked his eyes twice, only to see the lines still wiggling, enticing them with their random, chaotic dance.
"That's it!" Bob shouted. "That's the answer, man!"
Bob the Scientist went and grabbed Bill the Scientist. He pointed at the floor, saying over and over again "The lines, man! Look at the lines! Wooooooaaaaaahhhhh."
Bill the Scientist sniffed, and said to Bob "Bob...have you been smoking that crazy ganja again?"
"Yes, but so what? Duuuuude...the liinnnes...their taaaalking to meeeee..."
"Give me some of that shit." Bill the Scientist took a big drag, looked down at the floor, and they both stared. "Woooooaaaaaaah...we better write this down, so we don't forget!"
And thus, string theory was born.
Living With a Nerd
While you may not be able to run around claiming that String Theory is dead and disproved, evidently there are some adjustments that need to be made."
...again
String theory is one of those theories that get changed around every time they run into trouble. I can't imagine what it would take to have it go away, aside from a paradigm change.
Assorted stuff I do sometimes: Lemuria.org
It shows string theory is testable after all.
Even failing still sheds light on what is wrong with our theory (or reality if you're an economist :-).
If this work checks out, then it's "good science" (yay, a disproof!), and tells us a lot more about current ideas than the typical run-of-the-mill publications that exist today. At the risk of trolling: we have many broken or fudged models at the moment, and we need new ideas!
How can we be sure that the black holes were not created?
As one might suspect, the very opening to the paper in the arxiv explains this. After lengthy explanation of several peer reviewed papers that have been widely accepted on detection of black holes, they state:
The microscopic black holes produced at the LHC would be distinguished by high multiplicity, democratic, and highly isotropic decays with the final-state particles carrying hundreds of GeV of energy. Most of these particles would be reconstructed as jets of hadrons. Observation of such spectacular signatures would provide direct information on the nature of black holes as well as the structure and dimensionality of space-time [1]. Microscopic black hole properties are reviewed in more detail in [15, 16].
Now, as you can see by the [1], [15] and [16] references, each of these claims will lead you to a further longer paper on the concept of black holes themselves. Is it possible this method is flawed? I'm not a particle physicist so I'm not authorized to answer that. But I will say that this experiment has been a long time coming and I'm certain the authors of this paper were very careful in all their statements about String Theory.
String theory posits that there exist physical dimensions outside of our 4 dimensional universe, in fact that these are part and parcel of our universe. However, given our tools are all limited to 4 dimensions, it makes sense that there could be phenomena that is unobservable in our universe yet occurring in those other unexperienceable dimensions.
I know what you're saying but String Theory turns a lot of people off when its nature seems to be "unobservable" as you so put it. You'd have just as easy a time proving God exists as you would proving String Theory. The joke about String Theory is that it is conceived to make it untestable so it can never be wrong. This is dangerous ground and whenever a prediction is made by the theory that can be tested, it must be taken seriously. "Unexperienceable dimension?" Ahhh, I wouldn't go around talking to scientists about 'unexperienceable' things. I do not believe the scientific process looks kindly on such things.
I agree with the summary, this isn't the defeat of String Theory. It is a chance to refine and improve it.
I am the submitter, I don't think I said anything too far one way or the other. Usually Not Even Wrong points me in the correct direction but they gave this paper an unusually short nod with little correspondence or refutation. I think this is a good indication that everyone is waiting for the real scientists (not my lame armchair ass) to look this over and weigh in. You know, if you make predictions and they're wrong and you stretch your model to always avoid any sort of direct contradiction but you never get anything correct, then you look more like a fortune teller than a theoretical physicist. They should have the option to revise but my prediction is that this result will lose them a large amount of support in the community. It doesn't outright disqualify them but it sure is a vote of no confidence in a lot of the popular String Theory models.
My work here is dung.
The Hawking Singularity Detector shows different results. http://www.youtube.com/watch?v=FH5Xyj0yYjs
Undetectable Steganography? Yep, there's an app fo
Logically, the strings came from the first crappy but mandatory attempt to visualize the science for a documentary or a magazine. Science must be cool (says management), and therefore, we need full-color pictures - preferably moving pictures. Since 26-dimensional calculations are very difficult to visualize (see for example the end of Space Odyssey 2001), and you can't show the actual calculations either... Voila: strings.
Ok. I admit... my version isn't much better.
I think String Theory is vital! You take the early works of Chuck Berry, Carl Perkins and move through Hendrix, Trower and later Stevie Ray and without people furthering string theory then American Idol becomes the end-all! Granted we're in a glut of String Theory progress right now but these things are cyclical. I'm confident there's another genius out there that will take strings to the next level of understanding and I for one can't wait. And as for "tiny black holes," frankly the big one behind the strumming point on the strings has always worked just fine.
What a waste of 30 years and 4.4 billion dollars
Until it has some experimental evidence to support it, it should be String Hypothesis.
If Slashdot were chemistry it would look like this:Cadaverine
If you make adjustments based on experimentation, then your theory becomes nothing more than
"explaining the results" which is bad science.
In other words, the experimenter should not say "your model failed this particular test"
but "your model failed".
Both theoretical and practical physics are important. But I fear some theoretical physicists have become so disjointed form the practical side of things, they are engaging in nothing but science fiction. The self-reinforcing groupthink begins to build upon itself, some horrible academic paper generating force, a sociological phenomenon that bears no relation to what science is actually supposed to be.
Then we have something more akin to how religious organizations conduct the preservation, evangelization, and defense of their dogma.
This isn't physics anymore. Don't question string theory. It exists in a realm outside of reality, untestable, unprovable, unknowable. Except through the investment of faith in the academic movement that keeps the sacred thing alive.
intellectual property law is philosophically incoherent. it is your moral duty to ignore it or sabotage it
Either that, or he'll be on a complete tear to prove CERN wrong. I can feel a few Big Bang Theory episodes out of this!!
"the hypothesis by String Theory that micro black holes would be formed and quickly evaporated"
Better no black holes than black holes that didn't evaporate.
I haven't read Woit's post on this, but the whole idea that some guy who has for years claimed that string theory is "not even wrong" because it can't make any predictions suddenly changes his mind to say it predicted the Planck scale is below 3,5TeV is absurd.
Some Randall-Sundrum models might have been falsified, but I don't know enough to say whether they are part of string theory or not.
I remember in a math class, we were given series of numbers and we were supposed to determine the function that created them. For example:
1, 4, 9 ,16 Obviously asking for y=x^2
0, 1, 0, -1 Going for a sinusoidal wave
etc. etc.
Now, me being the smartass I am and completely bored decide to prove that an infinite number of functions can produce these series. So after digging in, figure out that if given a series of n items that I can reproduce it with at least one polynomial function with largest term of cx^n-1 terms and an infinite number of polynomial functions with largest term of cx^n.
So basically one can create a function to describe the limited information you have but not really answer what the "real" answer is.
This is what string theory reminds me of. You observe some things and find some convoluted explanation for it. If you get a data set that destroys the theory, you add another term to your equation and shout "VOILA" and declare that you have enhanced your theory.
Contrast this to the theory of relativity where new observations support its validity. Bottom line: string theory is not science.
See my journal for slashdot ID's by year. Mine created in 2005. http://slashdot.org/journal/289875/slashdot-ids-by-year
not yet the end of the world? with a runaway blackhole gulping earth... now that's a relief :)... maybe better (or worse) luck next time :)
Never antropomorphize computers, they do not like that
Well, string theory is indeed far from dead but I would claim that it does not even need adjustments.
The reason for this is that string theory contains within itself a large class of possibilities for the 'low-energy' degrees of freedom. (The name 'low-energy' is a bit misleading since those degrees of freedom are actually precisely the particles one may detect with very high-energy particle colliders like the LHC.) Naively speaking you can curl up your six or seven (or even eight) extra dimensions in such a way that they predict *very* different results for experiments like the LHC, and all of this can be done within the same string theory.
What the present paper says is that *one class* out of these very many possibilities should now be discarded. That is a nice and good result in itself but personally I am not too surprised since this class seemed a bit far-fetched to me anyway.
String theory is therefore still alive and kicking and this experiment certainly does not imply any adjustments are necessary to the fundamentals of the theory itself. Rather, string theorist simply cross out these options from their list, thank the experimenters for their efforts (thanks, guys!) and start looking for different ways of curling up dimensions... ideas are welcome! :-)
Disclaimer: IAAST
I happen to be an actual theoretical particle physicist. The headline and summary are completely misleading/sensationalist and this has essentially nothing to do with string theory. If I hadn't seen the string-theory connection here on slashdot, "string theory" would not even have crossed my mind reading this. If you happen to actual read the so-called "long statement" (which is only half a page really) you would have noticed that it doesn't say anything about string theory. What this measurement has ruled out are certain theories that have some small extra dimensions that would predict these tiny black holes. Those theories don't really have anything to do with string theory per se. The only conceived connection is that string theory also has more than 4 spacetime dimensions.
Calling this "string theory tested, fails prediction" is close to the following analogy: Someone comes up with a crazy theory according to which once a while (say 1 in 100) an apple that gets detached from a tree should rise into the sky (say by using complex numbers to cleverly generate a minus sign in Newton's laws). After having observed sufficiently many apples all fall down, we can now say with confidence that apples don't rise but in fact always fall. The slashdot headline would be: "Complex numbers tested, fail apple prediction."
So rest assured, no string theorist will have a sleepless night and none of them will make any adjustments whatsoever. The main reaction in the particle physics world to this will be a lunch conversation along the lines of: "Told you so, this whole idea about mini-blackholes was ridiculous in the first place, in any case, glad they rule it out, so hopefully this will quiet down this whole black-hole circus now."
Okay, I'm as interested in tests of String Theory as the next guy. But more importantly, if CERN can not create mini-black holes, can we stop with all the LOLZ THE WORLD ENDZ IN 2012 LOLZ!!!!
Is that to much to ask?
And preemptively, If you want to reply, IT DID CREATE THE BLACK HOLES, THEY DIDN'T EVAPORATE, THE WORLD ENDS IN 2012, LOLZ!!! I should point out that if i made the black holes that don't evaporate they'll end the world before 2012. Second of all, shoot yourself. Just shoot yourself, alright?
Democracy Now! - your daily, uncensored, corporate-free
"Fuck."
...for the cases of black holes with a mass of 3.5-4.5 TeV (1012 electron volts).
Ok, wtf is that bit in the brackets meant to be? A conversion into "common sense" units? From terra electron Volts to ... electron Volts? But the numbers make no sense at all!! Seriously, whoever put that in, go learn some physics. Or some maths. I can't even work out what units they were attempting to convert to there. Closest I can come up with is "two-third milli-ergs" ... but that's deliberately venturing into the realm of the riduculous.
1 TeV = 1,000,000,000,000 eV. So 3.5 - 4.5 TeV is 3,500,000,000,000 eV - 4,500,000,000,000 eV. Where the hell does the 1012 eV part come from? Graah!
The string theory is that cats like them, or not. I don't think the cats should be in a box though, that's just cruel.
Weren't there "only" 11 dimensions, or have they added some in the new catalog ?
What a depressingly stupid machine.
Does this mean I don't get my mhttp://science.slashdot.org/comments.pl?sid=1913170&op=reply&threshold=0&commentsort=0&mode=thread&pid=ini-black hole blaster?
I swear to God...I swear to God! That is NOT how you treat your human!
Not Even Wrong points us to the arxiv prepublication for those of you well versed in Greek
As the article is written in English, I'm trying to understand why you wrote that.
"I've got the world on a string. I'm sitting on a rainbow. Got that string around my finger"
HRH The Duke of Windsor
Who prays to string? Who says that anyone not understanding string should be killed?
It's a kind of religion in the same way as a lettuce leaf is like a car.
If you make adjustments based on experimentation, then your theory becomes nothing more than "explaining the results" which is bad science. In other words, the experimenter should not say "your model failed this particular test" but "your model failed".
Maybe they should tack a constant on the end.
Taking guns away from the 99% gives the 1% 100% of the power.
My god man, you found a black hole!
It's not just physics. The whole insistence on a rigid distinction between theories and hypotheses, in any field, is a sign of a ignorance of fundamental things about how science works. Anyone who's read Popper (whose stuff is almost 100 years old now) would understand.
Good; wise words. However M-theory (the new name for string theory) is a cluster of freakishly many theories, each of which predicts a different sort of universe. Many of these are still consistent with the data we have, and for whatever data we could ever get, I'm sure there will be some M-theory that's consistent with that data. So M-theory as a cluster is basically immune to any kind of empirical falsification. This might sound like a good thing, but it's just the opposite.
The summary is completely incorrect. Whoever wrote the summary simply didn't understand the paper. String theory does not predict the production of microscopic black holes at LHC eneries. The paper's abstract says, "Limits on the minimum black hole mass are set, in the range 3.5 -- 4.5 TeV, for a variety of parameters in a model with large extra dimensions, along with model-independent limits on new physics in these final states." Note that phrase "large extra dimensions." Here is the WP article on large extra dimensions. String theory has *small* extra dimensions: extra dimensions that wrap around on themselves at the Planck scale. The LHC doesn't probe the Planck scale. Theories with large extra dimensions have, er, *large* extra dimensions. This experiment falsifies those theories, not string theory.
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John Titor just died.
Proving the geocentric model is easy. The earth is stationary, space is the thing that's moving.
...Hooray for Science!
If they knew how long the string was then this problem would not exist.....or be......or..ahhhh......whatever!
A closed mouth gathers no foot.
I'm a frayed knot!
Currently hooked on AMP
Ha ha. Calling someone a tard when you can't even spell 'get' and 'stupider' correctly. Bonus points for the incorrect use of 'stupider'.
Double bonus for supporting the moronic notion that the use of a tilde can represent snarkiness.
Don't you have homework to finish?
Do not anger the Kaku.
And this is why the comments from dilettantes such as yourself are utter nonsense, you forever re-read your denier websites since reality wouldn't support your political opinions.
No, seriously...have you ever spent a long time at any scientific websites that really dig in a defend the science behind AGW? My guess is no. You peruse both sides, and just pick the one you agree with politically.
And, yeah, I've dug into both...unfortunately the denier websites don't have much depth to dig into.
I hate to say it, but string theory has always reminded me of Kepler's platonic model of the solar system: a wonderfully elegant description that is wrong. He spent an enormous portion of his life trying to make that model fit, but it didn't. The very fact that it was an elegant description was compelling to him, as I think string theory is to its theorists, but I'm not sure that should be counted as a point towards a theory.
I read Greene's "Elegant Universe", and indeed the initial insights of string theory are mathematically beautiful. But by the time he was talking about adding in lots of rolled up dimensions to make it work, I was starting to feel the theory was a little threadbare.
I suppose the proponents will rework the number of dimensions and such to account for these latest results. And maybe they'll find the One True Theory. Or maybe they'll spend another couple decades exploring a beautiful mathematical world that simply doesn't map to our own.
Cheers.
The depth of your ignorance is profound beyond measure.
"Oh, that's interesting. That toy model that has nothing to do with what we work on bar a couple of brief justifications and hand-waving about branes in 11D gravity implying we can work with branes in 5D gravity even though we have no dimensional reduction mechanism that we can trust that does this, is ruled out. That's interesting."
Nor do I understand Quantum ChromoDynamics. I am half way through Penrose's "Road to Reality" and I do not expect to understand either when I get to the end. That being said, the arxiv.org paper is fathomable at first glance (not so Greek). it is pleasing to see results coming out of the LHC. Science inches forward.
Slashdot: Where nerds gather to pool their ignorance
Among all the parallel Universies only those that did not produce small black holes survived HLC experiment and since we are still alive our Universe is one of them.
If enithin kan gow rong it whil. (Murfey)
This may be mostly off-topic, but I saw Michio Kaku on Conan the other night and he was talking all about string theory and how it's going to allow all of these sci-fi fantasies to become reality... and basically the guy seems to come off as a total hack to anyone with any semblance of a scientific background. Does he have any credibility at all among real physicists?
Until the theorists get back to us, wanna try hitting pidgeons with the proton stream?
that's exactly why I think cats should be in a box.
The Kruger Dunning explains most post on
A few posters are saying that there are many string theories. It would be more accurate to say that there's only one theory, but many models - if we define a theory by an equation of motion, and a model by a choice of initial conditions. For string theory, that means describing the space that the strings move through.
At the level of theory, string theory still doesn't have its fundamental universal equation. Probably that will come from the study of M-theory, the eleven-dimensional phase of the theory. Apart from M-theory, what we have are various fundamental equations for strings in ten dimensions, which correspond to different limits of M-theory. In the development of the subject, the ten-dimensional string equations were constructed first, and then the existence of M-theory was extrapolated from those.
To make predictions using string theory, you pick one of these fundamental starting points, and then you specify the geometric background that the strings will inhabit, and then you calculate their properties in that background. For example, you might look at "Type IIA string theory compactified on a T6/(Z2xZ2') orientifold". There is a very large number of possibilities.
So far, it hasn't even been proven that string theory can completely match experiment. This is because of the subject's mathematical difficulty. There are many models - many choices of the background space - which qualitatively resemble the real world, but it is technically very challenging to determine the exact parameters at which a particular geometric background will stabilize, and those parameters in turn determine observable properties like particle masses. It will be a big day for string theory when a class of models is found in which those geometric "moduli" are provably stable and in which the known particle masses come out right.
At a higher level, you might also hope that the fundamental equation of motion will actually determine the choice of background space, and not just how the strings behave on it. This is an even harder problem than moduli stabilization, though the two problems are connected; the moduli are the geometric parameters describing a space, and if they change enough, the space will become another space (e.g. it will change topology). So in both cases, to solve the problem, you need to understand the dynamics of the moduli. As things stand, the idea that string theory dynamically favors just one background seems like a naive hope from the early days of the theory. If we *are* living in a particular string model, some of its features may have been imposed by the anthropic principle, and the other features may just be "random". But we won't know for sure how to think about the theory at this level until we understand its dynamics much better than now.
So, when it comes to confronting string theory with experiment, there are two paths forward. First, you can hope for a spectacular qualitative indication that string theory is correct, such as the detection of supersymmetry or extra dimensions. Second, you can wait for the slow difficult advance of mathematical understanding to produce realistic models with stabilized moduli, or even a dynamical prediction of the background space. The LHC is guaranteed to show us something new - the cause of electroweak symmetry breaking, whether that's a Higgs boson or something else - but whether it will be spectacular enough to change the situation is unknown. If it doesn't, then testing string theory will depend on achieving those fundamental theoretical advances.
String theory is simply a way of using math to describe this world, the basics behind it are logical.
However since its only a math framework there are a lot of potential ways to use.
some say this is the downside of string theory, but string theory has allready been used to describe things in the real world.
So far those results never really forwared a specific version, but instead showed that the framework can be used.
Overall this means that we can describe nature in various ways, one of them is string theory but its not a finalized theory; in itself this is not strange in math.
For example we're still researching the distribution of prime numbers.
Math basicly is about logic and to extend our logic, its about frameworks of logic.
In the end it realy doesnt matter if there are strings or brains; or point like electrons; what matters is what we might be able to do with a working framework.
Sofar natures framework is still for a big part hidden, we have nothing to describe it all.
Sometimes in math there are shortcuts to calculate; if string theory turns out to be something like that, then it still is usefully.
Maybe we will need the math framework to describe quantum chromodynamics or we need other math toolboxes.
Its still waiting to be solved and maybe we never will be able to solve, not all math problems can be solved with our understanding of math.
Who are we to say that we will someday, maybe a computer someday will find a solution, but even so will we then be able to understand it to its full potential ?
I think a fish (we) will never comprehend the world outside the bowl although we pretend to do so.
And you're full of shit.
I think the String Theory spectrum looks more like Pure Mathematics practise than a theoretical physics endeavour. I think the problem is that (as of Lee Smolin opinion in his book The Trouble with Physics) too many distinguished professors and respected departments are so deeply (and for so long) involved in this business that a withdraw from this theory would cause too much embarrassment at this point. Too much money and time spend from research funds for over 25 years. How would you justify withdrawal by other means but by some experimental disagreement. Like Richard Feynman said, 'they keep finding excuses cocking up here and there looking for excuses', with other words to keep their careers and reputation intact. Can you imagine what it must feel like after being warned for decades that it doesn't make sense what you're doing, how would you react. I think Smolin was right when he said that this theory could damage science (in particular physics) reputation if it doesn't succeed. Lets be honest 30 years of development and still not one testable prediction? I mean can someone explain to me why they are pursuing a Theory of Everything TEO at this time while they haven't found the Grand Unified Theory GUT yet? And why seek a GUT while you haven't even finish with Quantum Gravity yet? It should have been in this chronological order right: Electric F + Magnetic F > EM EM + Weak F > EW EW + Strong > GUT GUT + Quantum Gravity > TEO What these people are doing is bypassing QG and GUT to reach at TEO in the hope to distinguish themselves, collect the Nobel Price and become immortals. To my opinion, the reason why there is no TEO yet is because currently there are no scientist bright enough e.g. like Einstein and his colleagues of his generation to take this challenge. Feynman was the last of that kind of breed. Until another bright by birth dude wont come along we will have to wait patiently and be content with general relativity and quantum mechanics as two separate frameworks but that works very fine for our needs (GPS, computers, condense matter, etc). If we want to know about what happened during the big bang and what is inside of a black hole we would have to wait for another Einstein type to be born again. Witten, Greene and all other current leading physmathist are simply not of the same league as Einstein and his generation, plain simple! These people have chosen the wrong career path, instead of theoretical physics they should have followed pure mathematics. In this way they would have made sense. But now it is too late!