Cern is asking—did it happen? Or is there an error? Or is there a situation we don’t understand?
Speed of light broken?
by CJ | Nov 21, 2011 | Journal | 32 comments
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http://www.bbc.co.uk/news/science-environment-15017484
Actually the news report is from next week; so it’s looking like causality has taken a bit of a hit.
Side note; I was a speaker at a conference after one of the leads on this story. To say they were puzzzled and annoyed would be a mild understatement. They are certain they are wrong but cannot find out why.
A new and fairly definitive refutation of the FTL result was released today:
Study rejects “faster than light” particle finding
And more technical detail here:
ICARUS Refutes Opera’s Superluminal Neutrinos
It looks fairly conclusive, but they will still have to find the error in the Opera experiment.
Their definitive refutation is more than a little inbred to my way of thinking. They are refuting an exception of the Theory of Special Relativity by …. Ta Da .. a nearly tautological portion of the same theory. A more humble presentation would say that there is no previous evidence that would lead them to believe that the neutrinos could be tachyons without having lost energy in the process.
Um… no. The refutation has nothing to do with Special Relativity.
The actual paper can be downloaded here (PDF download of the full paper at the top right).
I’m not current, nor was I ever especially well versed in the subject of nuclear physics and I can’t really follow the equations, but.. High energy and particle physics as an experimental and theoretical science has Einsteinian principles at its very foundations. Without that, particle acceleration in general and this experiment in particular would be literally inconceivable and the results meaningless. Any general physics equation dealing with near light speeds and/or extremely dense energies that is both predictive and verifiable must have Einsteinien DNA at its roots else it would fail miserably in conditions where relativistic effects are prominent. I’m ready to be persuaded, but I really can’t imagine that any event with material relativistic influences can be described or explained without using relativistic theories and equations.
A question from the front of the class, where I sit with some decent old college calculus, was terrible at physics, and a more liberal arts (languages and literature) understanding, with some computer science thrown in, pre-internet; in fact, just after Mac and Windows.
So, with such background, this student wonders about the Emperor’s Clothes, with a question perhaps as uncomfortable:
OK, probably they are right and FTL was not exceeded. Are they certain this was an error in data, and not an error in the current scientific theories’ (and professors’) understandings? In other words, what happens if FTL is, through some unforeseen way, exceeded by means natural or technological? More uncomfortably, what is to prevent an attempt to keep the status quo and explain away an actual event by current theoretical, equational means? What happens if there *is* some unknown exception, but the theories and equations we currently have are…incomplete in understanding and in error themselves, somewhere, rather than an event with its data? — Not casting aspersions, but asking, because that’s a basic science question: Suppose our current ideas are not complete or not quite as right, or maybe just plain phooey in some particular spots? If there *were* some odd event, in nature or by technological intervention, then, well, how would that be proven an exception, a positive? — Not that I’m likely to understand an explanation beyond simplest terms, but just for the sake of raising the point. 🙂
Oh, and of course, if the Emperor looks rather fetching without any clothes on, well, that’s another issue (in the) altogether. 😉 Just, you know, for further bemusement.
Back in college Calc III, I was fine if you threw any problem at me. I liked it. But physics? Whatever you do, don’t put me in charge of ship’s astrophysics or navigation. I nearly always forgot or misplaced or added a force somewhere it wasn’t supposed to be; frustrated me to no end. These days, I’d have to have my nose buried in textbooks catching up with what of trig and calc I’ve forgotten, but I’d eventually be back up to speed. Physics? Please get someone else doing the figures. Though I’d love to listen to Dr. Sagan or Dr. Kaku or Dr. Hawking. — Give me some ancient manuscript, language samples, and so on, and I’d be thrilled. Put me at ship’s com/comp, and I’d be likely happy, figuring out what the aliens are saying/signing/coloring/wiggling/singing.
Yes, the whole question that’s being debated and investigated is whether the measurements are wrong, or whether the theoretical understanding has to be modified. It must be one or the other.
Science progresses by constantly modifying our abstract understanding of Nature as new information comes to light.
It’s just that relativity has been verified so thoroughly and so often, in so many different ways, over a period of so many years, and has been used for so many practical purposes, that scientists are skeptical that it needs to be revised.
However, if the data is right and the theory does need to be changed, it would be a major breakthrough in physics. It would be the start of a whole new era in scientific research. Physicists would absolutely love it if FTL neutrinos do turn out to be true – it’s just that it looks highly unlikely on the face of it.
The repeat of the Opera experiment removed one possible cause of measurement error, but the whole setup is massively complicated, and there could be other causes of error.
Many hundreds of physicists will keep working on it until they either find the cause of the measurement error, or the result is verified by similar experiments elsewhere which are unlikely to share the same source of error. In that case, they will start working on a major revision of our whole understanding of way the universe works.
…And if they do find some FTL exception, I’d be tickled…blue?
The bartender says, We don’t serve your kind here.”
*
*
*
An FTL sub-atomic particle walks in to a bar.
Very funny. Had to think about it for a moment.
Phil Brown
I’d be more worried if the bar had a Moebius Stripper. (Eek, on second thought, not as funny as at first thought.)
But I suspect if there were a causality effect where you end up before you begin, the show might lose appeal. Heh.
@ GreenWyvern, Thanks, that clarifies things some. While they’re busy recalculating to check the figures, I hope somebody puts out the welcome mat and brews up some more tea and coffee.
Ah, Möbius strips. I remember a short story about an underground train system that accidentally incorporated one of those.
Ah, I think this is it:
http://kasmana.people.cofc.edu/MATHFICT/mfview.php?callnumber=mf102
I remember a Thieves’ World story, where a gate to a demonic dimension was closed by the bard taking the scroll that had opened the gate and folding it on itself to make a Mobius strip, thus making the gate unable to be open in our universe. One-dimensional topology FTW!
One of the less outlandish but interesting explanations would be to say that the true speed limit in the universe is the speed of neutrinos, and normally light travels at the speed of neutrinos. However, in certain circumstances (say the presence of a graviational field) light travels slower than the speed of neutrinos.
Such an adjustment to relativity might also explain the ever-so-slight timing discrepency in supernova 1987a between the light and neutrinos arriving. The percentage speed difference on that was far less, but when travelling through interstellar space, both the light and the neutrinos would have been in strong gravity fields far less often that during Opera’s earth-bound experiment.
But I’d do cartwheels if this turned out to be the unlocking of the FTL gateway.
Actually, in General Relativity (as opposed to Special Relativity) gravity does come into it, and in some kind of strong gravitational field, light (and other things) can go a lot faster.
The problem with General Relativity (the part with gravity and acceleration) is the mathematics is a lot harder to understand than Special Relativity (the part with the speed of light). Special Relativity uses high school algebra; General Relativity involves tensors and differential equations and manifolds.
As for the speed of neutrinos being the “real speed” and that of light being close to, but not the same: I see a bit of a problem with that, though it may be more of a philosophical one than a practical one. The speed of light isn’t just the speed light happens to go. The equations for electricity and magnetism determine how fast a light wave will go. The fact that they do, is part of the motivation for saying that the speed of light is constant (in special relativity). They don’t say how fast a neutrino will move.
Which isn’t to say the equations couldn’t be something different. But it wouldn’t just change how fast light moves, or really really light particles — it would impact the behavior of electric and magnetic fields which we deal with a lot more often.
And just to be honest, when I say GR “is a lot harder to understand” I also mean: I don’t understand it. Even a degree in math, gave me just enough to grasp “what it’s about” and no deeper.
Many years ago, I read a pop-math book (maybe The Education of TC Mitts?) In explaining relativity, the author said that Einstein had taken the unbreakable speed of light as an assumption — a starting point in his theorizing.
As though he said, “Nobody has ever discovered anything faster than light, so it must be the winner.” The resulting theory has, as mentioned, been verified and formed the basis of many advances in knowledge.
Still, I wonder what replacement assumption Einstein would have made if FTL was discovered before he began theorizing.
Einstein developed the theory of Relativity to explain various anomalous experimental observations which could not otherwise be explained or understood. He didn’t just dream it up out of nothing.
He also didn’t start by thinking in terms of objects moving in different frames of reference, the way that Relativity is often explained in simplified texts. He started out by looking at electromagnetism and trying to reconcile Maxwell’s equations with mechanics, and explain the Michelson–Morley experiment, which had unexpectedly shown that the speed of light wasn’t affected by the motion of earth.
These were major unexplained experimental phenomena at the time, and many physicists were trying to find a way of explaining them.
Einstein’s original paper on Relativity was entitled “Zur Elektrodynamik bewegter Körper” or “On the Electrodynamics of Moving Bodies”. The correct way to understand Relativity is to start with electrodynamics, and look at what experimental phenomena needed to be explained and how Relatively explains them.
A very important thing to know about physics is that it’s not possible to understand physics by reading popular science books. The language of physics is mathematics. The only way to understand physics more than very superficially is to understand the actual, rigorous mathematics of it.
Don’t mistake simplified pop-science descriptions of physics for actual physics.
Popular descriptions of physics are sometimes referred to by physicists as ‘hand-waving’ explanations. The real explanation is in the mathematics, everything else is just ‘hand waving’ – talking fast and waving your hands about excitedly to try to persuade someone.
Quote: “everything else is just ‘hand waving’ – talking fast and waving your hands about excitedly to try to persuade someone.”
And just what is that the physicists are doing when they write their fancy math equations on their blackboards? 😀
Truly, the equations are a (much more) rigorous description of what is going on, and we still need some physical embodiment of them before we can make use of them. Some engineer has to get her mind around the concepts and beat them into submission.
These are fascinating times we live in.
On a completely unrelated note, a bit of sorrow: Anne McCaffrey has died D:
Again from the liberal arts plus Calc III and some comp. sci. perspective:
Well, one of the things about physics is that it applies the same rules throughout, whether it’s a simple, everyday object, such as a person or horse or car, to something more exotic, like a star or spaceship or a neutrino or lightwave or microscopic lifeform…. The scale of things, the order of magnitude, may mean some things apply “more” than others in a given situation, but it’s the same thing affecting an oak tree as a starship or a planet. (Yes, very broadly speaking. Neutrinos and black holes and such may be so mind-bendingly different that the same rules apply rather differently. (Scale and magnitude again.)
In other words, a simplified explanation, an elegant simplicity and commonality of effect, is what makes it possible to teach the concepts in the first place, to observe and develop working theories, and to explain them in popular science documentaries hosted by a professor able to bring it across and excite the imaginations of the general public, and perhaps future students.
(Well, of course, BlueCatShip, but so what?)
The scientific understanding always has to get refined, because our understanding of the universe is incomplete, imperfect. There’s always some new special case or a new question, leading to something else. “And then what? Well, what if? How does…? Why?” There are things we simply don’t know how to explain, a few of which might not be solvable by the empirical method of science. But the drive to “figure it out” and — to make something useful or beautiful from it — is crucial.
(Oh, that also seems rather obvious. Something tells me I need to re-examine my thesis and decide what I’m defending, before I try to make some persuasive argument.) (Aha, the editor and liberal arts side of me appears to have awakened, finally. Heheheh.)
Ahem, sorry, I believe I’ll just go back to taking notes. :embarrassed-grin:
You know, this all would’ve turned out differently if Isaac Newton had sat near a watermelon patch, or if René Descartes hadn’t watched that silly fly crawl across the ceiling….
(No, BCS, bringing in a literary example doesn’t establish a new thesis or persuasive argument.)
Yeah, but what if René had had a flyswatter or a can of bug spray?
OK, ya got me on that one.
I do wonder, though, how the fly managed those (x, y) coordinates….
Oh, now you’re just being cheeky! You know that passage better than that, doofus! 😀
BCS, I’d point you to Feynman’s lectures where he warns us about trying to understand things in everyday, experiential terms. One of the most fundamental conundrums of physics for the lay person is, “Are photons particles or waves?” “They are both,” hardly promotes understanding. But in a way it points to Heisenberg, for it clearly shows ‘what you see depends on how you look at it’. The mathematics itself, which for most of us doesn’t translate to ‘real’, works but our experiential level is based on ’emergent properties’ and can’t help us at all at the QM/fundamental particle level.
I had up through Calculus III, so I can appreciate that there’s more to things than meets the eye. The possibility of more than one thing at once, duality or multiple realities, I can somehow appreciate and somewhat wrap my brain around the idea (or it wrap itself around mine). Heck, I *like* the unusual about it all, the exotic, the weird, the wonder, the what if.
I hope I wasn’t over-simplifying or implying things should be somehow immediately obvious and simple to grasp. There are plenty of questions that are not easy to figure out, and never will have an easy answer. That’s why we keep at them, trying to come up with something that works. Whether it’s philosophy or physics or metaphysics, the questions are worth it.
I suppose even all the ugliness of violence and intolerance are in some way attempts to come up with answers, a struggle to deal with what seems unworkable. I don’t know. But on that, surely there’s some better answer available.
Hmm. I don’t recall the source of the quote that intelligence is the cosmos trying to understand itself, but that puts it neatly.
That’s the thing about physics: I was bad at physics, but the math (calculus) was something I liked, and the questions raised by physics, I like a lot.
“Hydrogen is a colorless, odorless gas, which if left alone in large enough quantities, for a long enough, will begin to think about itself.”
I did try to look that up, found a few minor variants, “…turns into people,” but never an attribution. But it sounds very much like something Carl Sagan would have said.
“Not only is the universe stranger than you imagine, the universe is stranger than you CAN imagine,” (JBS Haldane, British Geneticist) is perhaps apropos of modern physics.
Hmm, and I really wish the people who think we shouldn’t ask some questions, or that being “different” is wrong, would see the larger picture. I don’t think any of us can see the whole picture, so we’re all a bit off the mark. At least, hopefully, we try.
@Paul – Re: Consciousness arising from hydrogen atoms.
I just wanted to say a few words about this since I am writing a book on the nature of consciousness.
The idea that conscousness can spontaneously arise from inert matter is very strange. When you think about it, it’s just as weird, just as far-fetched, just as unscientific, and just as much an article of pure faith as believing that bread becomes the body of Christ. Believing that mind arises spontaneously out of matter is comparable to the Aristotelian belief about the spontaneous generation of worms and insects from decaying matter. It doesn’t stand up to logic or experience or scrutiny.
A purely materialistic understanding of the nature of the universe falls down when it comes to consciousness.
It’s interesting that some of the gratest physicists, who laid down the whole basis of modern understanding of physics, didn’t think this way.
Many of them had very interesting thoughts about consciousness, including Niels Bohr, Erwin Schrödinger, Werner Heisenberg, Wolfgang Pauli, and Max Planck. Their views were certainly not the kind of standard materialism which you might expect. I doubt whether any of them would agree with the simplistic “mind is just a complex electro-chemical process in the brain” approach which is so common today.
Here are a few quotes from some of the most respected names in modern physics.
Max Planck (Nobel Prize in Physics, originator of Quantum Theory):
“As a man who has devoted his whole life to the most clear headed science, to the study of matter, I can tell you as a result of my research about atoms this much: There is no matter as such. All matter originates and exists only by virtue of a force, which brings the particle of an atom to vibration and holds this most minute solar system of the atom together. We must assume behind this force the existence of a conscious and intelligent Mind. This Mind is the matrix of all matter.”
“I regard consciousness as fundamental. I regard matter as derivative from consciousness. We cannot get behind consciousness. Everything that we talk about, everything that we regard as existing, postulates consciousness.”
Werner Heisenberg (Nobel Prize in Physics, Heisenberg Uncertainty Principle):
“I think that modern physics has definitely decided in favor of Plato. In fact the smallest units of matter are not physical objects in the ordinary sense; they are Forms, ideas which can be expressed unambiguously only in mathematical language.”
Wolfgang Pauli (Nobel Prize in Physics, Pauli exclusion principle):
“The natural laws of matter are the physical manifestation of the archetypes.”
“The layman always means, when he says ‘reality’ that he is speaking of something self-evidently known; whereas to me it seems the most important and exceedingly difficult task of our time is to work on the construction of a new idea of reality.”
Erwin Schrödinger (Nobel Prize in Physics, Schrödinger equation – the basis of Quantum Mechanics):
“The observing mind is not a physical system, it cannot interact with any physical system. … Sensations and thoughts do not belong to the ‘world of energy’.”
“There is no kind of framework within which we can find consciousness in the plural; this is simply something we construct because of the temporal plurality of individuals, but it is a false construction… The only solution to this conflict insofar as any is available to us at all lies in the ancient wisdom of the Upanishads.”
We do not belong to this material world that science constructs for us. We are not in it; we are outside. We are only spectators.