CERN are off their rocker
Here's a rational look at these folks and their "problems" with software.
Only weeks since mathematicians proved it couldn’t be done, CERN boffins have put the smile back on sci-fi fans’ faces everywhere by discovering neutrinos travelling faster than light. The astonishing results, reported by Reuters and others, came as the result of the OPERA experiment in which 15,000 beams of neutrinos were …
Oh noes! It's written in C++!
Obviously, if you are truly serious about writing software that won't get hacked, you must write it in a language that hackers do not know. Something like... er... lemme think... COBAL.
That way, if you're ever hacked you know you're looking for a hacker in his 60s, something of a rarity.
because you are the only person who knows about it!
I suspect that you mean COBOL, and if there is any modern (post millennium) serious scientific application (I will not accept financial software as falling in this category, even if it is for scientific establishments) written in COBOL, I'll eat my copy or K&R.
COBOL was able to add up numbers of arbitrary length (directly in decimal, usually) while others were stuck with 16-bit ints. Even 32 bits only gets you to $20M (with pennies). So it can do 'hard sums' in that sense.
But, go write a COBOL procedure which finds the inverse of an m x m matrix, with variable m, and report back to us how it went. And if you succeed, let us know how fast it runs relative to the C or fortran version.
Yeh, yeh. Very droll.
I was trying to exclude the daft things students do at University.
But seriously, Cobol is quite definitely a commercial language, and is not at all suited to scientific work. It's missing lots and lots of things you take for granted in any language more suited. There is only one language (apart from the out-and-out weird ones for specific purposes) that I can think of that is less suited, and that is RPG!
On the subject of 6502 assembler, I'm sure if you looked hard you may still find a BBC micro or two buried in the depths of some lab. somewhere. BBC basic was written in 6502 assembler originally, and people did lots of interesting things in that, so 6502 assembler by proxy.
COBOL is a just SQL.. or rather it is a version of SQL written by an evil genius - who decided to write a programming language where your code's failure to compile is dependent on time rather than errors. The more time critical your project, the more likely your code will fail to compile.
You can take the exact same code that failed to compile one day and it will work the next, as long as your deadline has already passed.
No, that is not a rational look, it's an irrational rant. Of course ROOT has bugs; every large software system ever written has bugs. And of course such bugs can increase the systematic error in a scientific result - actually the systematic error is always more worrisome than the statistical error, because what if some source of systematic error has been overlooked? But there's no news here. Archimedes had systematic error in his experiments, and so did Galileo.
Thus, a deviation of 20 ppm may or may not mean anything - hence, the next step will be an independent experiment somewhere else. And in any case, do you know whether ROOT was used for the OPERA analysis?
The first computer course I did (long after I had taught myself how to program) was mainly full of stuff that I already knew, and so tended to be boring. However, it did introduce me to a couple of rules that I still hold as fundamental:
Rule 1: No non-trivial computer program either a) works perfectly first time, or b) is entirely free of bugs
Rule 2: Any programming issue can be boiled down to one of two things: a) Garbage-in:Garbage-out, or b) Speed
For pointing out the silliness in the reporting, and the importance of the scientific method - BRAVO! HEAR HEAR!
This isn't a case of "They arrived in half the time", this is a case of barely measurable, maybe something maybe error, squint and it goes away type errors. Neutrinos are hard to detect, and by the time you go from impact to scintillation to detection, there's enough fuzz on this measurement that, while it's "more than noise", it's also still "less than a clear signal".
... just not faster than light in a vacuum (which the rocky 700km between CERN and "Big Rock" aren't).
The Cherenkov effect --- the greenish light always seen around say nuclear fuel rods in cooling water for example --- is exactly that, (charged) particles going faster than light in the medium at hand.
They're comparing to the host-to-goodness, full-fat, speed-limit-o-the-universe in vacuo speed....
A better comparison would be with the apparently super-luminal velocities of the plumes of active galactic nuclei 'observed' a while back... Further (non-trivial) research showed that actually, all was right with the cosmos and it was illusory.
Hmm, I could either pull up a reference for this, or down tools and head to the pub.... Guess which is likelier
60ns measured, vs 10ns error. They also repeated the measurement 15,000 times. I agree there is room for systematic errors in the OPERA experiment, and we should simply wait for confirmation (or the reverse) from independent experiments.
It ain't over till the fat lady signs
is true. The result isn't valid unless it's replicated.
But if it *is* valid, the science reporting is spot on. It's not just popular science that has elevated relativity to an absolute limit - it's science itself.
If the reporter knew anything about relativity he'd understand that relativity is a philosophical position about causality, and not just some fancy footwork that describes velocities in a counterintuitive space time.
Mainstream science has been insistent that the speed of light is an absolute limit for most of the last century.
If it turns out it isn't, that's not just a bit of an adjustment and an extension to existing models - it's a complete revision of how reality works.
"Mainstream science has been insistent that the speed of light is an absolute limit for most of the last century."
It has always been a concern of mine, whether the limit really is the (max) speed of light, or whether it is actually something a fraction faster.
In any case, E=mc2 only really applies to 'normal' stuff with measurable mass - it has always seemed likely to me that there are particles out there that differ so much from 'normal' as to allow them to ignore this rule.
Indeed, is 'c' the limit to the speed of light, or a more general limit that light maybe doesn't achieve?
I recall, back in the days when people were actually measuring the speed of electromagnetic radiation, that the speed of radio frequency radiation appeared to be a little different to that of light.
Have the theoretical physicists ignored this since?
If an object has any mass (which neutrinos do) as you approach the speed of light the amount of energy required goes to infinity correct? Just like with tachyons this applies in both directions both faster and slower. I guess of course this only applies if you follow the curvature of space time. Hope this is another cold fusion moment.
The shortest distance between two points is the line along space-time curvature. Not following space-time merely slows you down and requires more energy.
To my knowledge the only tested 'faster than light' phenomena are - quantum tunnelling, entanglement, and these meta-materials - all of which aren't really 'faster than light' in a strict sense, or are quantum uncertainty in action.
that relativity predicted that you could not travel at the speed of light, because it would imply infinite mass and thus infinite energy.
But if there was a dis-continuous way of jumping over the speed of light without actually accelerating through it, I believe that the equations could still hold, although I suspect that it would require a completely new branch of physics to explain the dis-continuous speed jump in the first place, and also some strange concepts like negative mass.
I'm expecting serious physicists to rip this suggestion to shreds ( I got no further than Principal Physics in my General Science degree thirty years ago - equivalent to the 2nd year of a normal Physics degree), and I'm expecting to be thumbed down, but it will be interesting to see what is said!
which takes different forms but the easiest expression to work with is 1/sqrt(c*c - v*v) where c is the speed of light and v is the observed speed of the object. If v=c the divisor is 0, iv v>c the divisor is imaginary. What division by 0 and what imaginary might mean is left as an exercise for the student.
Einstein essentially reasoned that is was an inherently continuous process and you could therefore never get an object with mass to the speed of light. Since quanta are very, very small quantities of energy, and increased acceleration requires every increasing amounts of energy, it seems a reasonable assumption.
I think you missunderstand what infinity is, in the sense you are talking about it's a process by which it's incremental, it's not a value something can "change to". I think it's more likely that if you go faster than the speed of light it's reasonable to say that the amount of energy required is an unknown by current thinking. It can't just be set to infinity like it's a cap.
Nah I'm pretty sure stimulated emission (Einstein A and B coefficients) were derived from thermodynamic arguments. Lasers work due to population inversions and stimulated emission producing coherent photons, neither of which has much to do with special relativity (Though if you can prove me wrong I'd be interested to read about it!)
Also Destroy All Monsters there is QM that doesn't depend on special relativity, the Dirac equation is good for explaining spin-1/2 particles travelling at relativistic speeds, if they're going slow you don't need to use it.
Perhaps remarkably, Maxwell's equations indeed are relativistic, and were so before SR was proposed by Einstein. If you want a plausibilty argument, then consider that SR uses light(speed) propagation to establish a metric, and that Maxwell's equations describe light propagation.
Otherwise, I suggest you go read any EM textbook.
Or ponder why, post-SR, Maxwell's equations are so popular.
Or feel free to invent a theory of non-relativistic light to describe your laser. Good luck with that, eh.
But if the neutrinos really are faster than light, and the wormhole appears next, right on schedule:
Mightn't someone will have persuaded Einstein to retrogave Maxwell a heads-up about rewritten his equations willen to became relativistic?
It doesn't really work like that, the Maxwell equations are invariant under a Lorentz transformation, which means in different moving frames of reference they are the same, or you can also say that the speed of light is constant in any frame. This doesn't necessarily mean that a working laser proves that special relativity is correct just because light is involved somewhere. You can show how a laser works without involving SR at all.
A better example of SR would be time dilation of relativistic particles http://en.wikipedia.org/wiki/Time_dilation_of_moving_particles
That the speed of light is not really a constant.
The correct phrase is speed of light in a vacuum is a constant. And even then it can change infinitesimally with the quality of the vacuum.
Given that neutrino's are famous for only weakly interacting with the material universe it's no surprise that they zip along a fraction faster. Z m
One of the more 'believable' tropes of science fiction is that 'FTL travel' is possible by generating or entering a domain where the speed of light is much faster than in our normal universe, thus technically not passing the speed of light. Handily it also gets around the near infinite mass/energy requirements that reaching lightspeed is meant to require.
The fact that neutrinos have mass and appear to travel faster that light opens the possibilities for lots of fascinating new science.
You appear to be struggling with two different meanings of the word "vacuum", here. Consider that in relative terms, the Earth's core can be considered a partial vacuum if you compare it to the density of the material at the Sun's core.
At least you don't think we're talking about hoovers.
I think what he means is that because of quantum jitters - disturbances created by the spontaneously appearing / annihilating of virtual particles at a quantum level - it might be possible for a particle like a neutrino which is extremely weakly interacting, to travel faster than other particles who might feel the 'drag' of these quantum fluctuations.
because the photons still need to pass through the medium, and the information is passed by the photons. The focus point is keeping causality in tact, and one of the observations which is key on this is being able to detect the orbit of pulsars around other stars. If strict Newtonian physics held you would get a confused signal. The speed of light in a vacuum is taken to be the uberlimit because vacuum has the highest speed for any medium.
I would imagine that the scientists in question understand and have already taken into account the speed of light in a vaccuum vs the speed of light in an atmosphere. I mean we're talking about world class boffins here. Do you really think they'd make mistake on something that even a high school physics student understands?
For that matter, how did they measure the distance? At light-speed, 60 nanoseconds is less than 20 metres. That's 20 metres along a path of 730000 metres through solid rock dipping through Earth's gravitational well and back up again.
I dare say they've thought about all of this (coz it's their job and it only took me ten seconds over breakfast to come up with that) but even forewarned of all the complications, this is a *really* challenging experiment.
Oh, and as others have pointed out, *all* the neutrinos seem to be travelling at the same "only ever so slightly faster than light" velocity. If they aren't limited by c, they sure seem to be limited by something awfully close to it. This is too much of a co-incidence. As the experimenters themselves say, the result is crazy.
The point, which El Reg seems to have picked up on but the mainstream media have missed entirely, is that the scientific interest here is not "Is this true?" because not even the experimenters believe that it is. The point is "Why can't we figure out where we've gone wrong?". This is fun stuff for physics geeks, but not (ultimately) interesting for anyone else.
Not between a straight line and the curved surface of the earth, between two curves along the surface of the earth: one the line they think they cut, the other along the path they actually took. Also, have they accounted for the gravitational warping of the path due to differing densities of the rock through with the path passes when they measured the distance.
Perhaps the two clocks talk to each other? You know: One sends a signal to the other with a time stamp. The second returns the signal with the received time stamp. Then they swap and the second sends first. That gives them the time it takes to send and process a signal. Now you can synchronize both clocks and you have the means to check they are in sync.
That's just off the top of my head, of cause...
Gravity doesn't slow light, same way that light emitted from a moving vehicle travels at the same speed as light emitted from a stationary source. The speed of light depends only on the medium - photons in a vacuum are always travelling at 'c'.
Even inside the event horizon of a blackhole they're travelling at 'c', they're just travelling in closed orbits.
In the presence of gravity the speed of light becomes relative.
Einstein theorized that the measured speed of light in a gravitational field is actually not a constant but a variable depending upon the reference frame of the observer.
I would have been more interested in a "race" between neutrinos and light.....first past the post is faster: relatively speaking.
Photons have no mass, so are 'lighter' than neutrinos.
Gravity doesn't slow light down, it warps space-time. Time passes more slowly in a strong gravitational field, but the speed of light is constant.
Given the enormous number of measurements confirming relativity to a very high level of accuracy, is unlikely in the extreme that these new results 'break relativity' or show that weve been 'measuring the speed of light wrong'. It is more likely that these results are either inaccurate, or that there is something more subtle at play.
Like the author of this article, I urge people to ignore the press hyperbole, and let science be done in a scientific way. To quote report author Antonio Ereditato of the Opera collaboration --
"When you don't find anything, then you say 'Well, now I'm forced to go out and ask the community to scrutinise this." .... "we are not claiming things, we want just to be helped by the community in understanding our crazy result - because it is crazy"
Einstein published his theory of relativity in 1905, and neutrinos were *postulated* in 1930. Now it looks like this is the first time that the speed of neutrinos have been actually measured. Is this truly flouting the "laws" of the universe, or did we simply make a good measurement? I really don't think that this is going backwards in time at all, it's just that a particle that was unknown in 1905 really happens to move faster than another particle.
It goes a bit deeper than that.
In special relativity, the speed of light "c" is constant when measured in any inertial frame. In general relativity, this means that the speed of light is constant in any freely falling reference frame (in a region small enough that tidal effects can be neglected).
If general relativity is correct, then the constancy of the speed of light in inertial frames is a tautology from the geometry of spacetime. The structure of the universe is determined by the geometry of "null vectors". Travelling at the speed c means following world-lines tangent to these null vectors.
c is not merely the speed of light, it is a fundamental feature of the geometry of spacetime.
But how do we know what c is? it is just a number that we have determined through measuring the speed of light, where we have assumed that the speed of light is c.
Just change the name of c from "the speed of light" to "the speed of neutrinos" and say that light travels slower (but not by much) than neutrinos in vacuum, due to some as yet unknown coupling (the same way light travels slower in media anyway)
Spec rel and gen rel still hold, c is still a constant, and nothing can go faster than c.
What this discovery means is not that we have found something that breaks the laws of physics, but that we have found that light travels slightly slower than c, and neutrinos do not.
(Whyever reply as anonymous to something like this??) According to what I've read, the speed of light still hasn't changed. A photon hasn't been sped up, and nothing has gone backwards in time. We have a good reading of the speed of a neutrino. It would be great to get more readings.
Fermilab had similar results four years ago, but they had a much larger margin of error. Perhaps the CERN team could send a beam at the Minnesota facility, and get some more data.
As our scientific searches progress, there is nothing that prevents the real existence of something moving faster than a photon. The mathematics based on photons remains the same, it's just that we need a whole new set of mathematics for other particles. Like Euclidean and non-Euclidean geometry, there will be theories describing the real measurements we make with neurtrinos, and maybe in the future, dark matter.
But none of this means that we'll make a time machine, warp drive or hyperspace engine, or flying car.
>But none of this means that we'll make a time machine
>warp drive or hyperspace engine
Probably wrong. This is exactly the sort of discovery that might one day allow FTL travel, even if only for signals, not ordinary old spaceships. This is the sort of exploit (for the lack of a better term) in the security model of the universe that might allow all this.
The neutrino burst from this was detected 3 hours before the first light, which was expected because the neutrinos travel from the collapsing core to the outside much faster IN THAT MEDIUM than the light. This is because the photons are constantly absorbed and re-emitted by all the nuclei and electrons in the dense stellar matter, whereas the neutrinos move like ghosts through everything. If the current difference is correct, the neutrinos should have arrived 4 years before.
Now these neutrinos may behave differently than the ones observed in OPERA, but it shows not all neutrinos move faster than light.
A friend who is a plasma physicist, had his doctorate paper turned down several times by Oxford University because it challenged existing physics facts laid down by Amper.
He finally got his doctors certificate because the results of his painstaking physical experiments, which had been conducted over several years, were some time later coroborated by other physicist who had used a super computer.
"Extrordinary claims require extrordinary evidence."
It is good (and likely significant) your friend's research was eventually accepted, but that sort of thing is pretty necessary in science. It marks the difference between a scientist with controversal data and a crackpot, and it is a painstaking and time-consuming line to mark. Your friend should be extra proud in this case and deserves full kudos!
its nothing amazing, all atoms die, light has never been a constant, or shadows would not exist and light beam would not fade after heating surrounding hydrogen in the armosphere then cooling
lightspeed does`nt mean you time travel either, in a neurtral void in space that would probaly make light speed possible, watches wouldnt work unless they are digital, which is the same as the upper atmosphere
a lightbulb heats up hydrogen to create a lightsource, hydrogen is the most common element in the universe, heat is making 99% of light that is in the universe
all atoms and whatever eventually diei, so it is impossible for light to be a constant, except on speed
e=mc2 is a pinhole in a 40foot canvas, in the quantum theory of it all. neutrinos are used because they have no electric field causing friction on gravity, so the nrutrino is travelling in a neutral pocket of space
I thought the previous article only showed that light could not go faster than the speed of light in a vacuum. Thus, the correct conclusion was that light could not travel back in time.
Also, my recollection was that Einstein only said that nothing else could travel at the speed of light. Meaning that nothing could accelerate from slower than light speed to faster than light speed and vice versa.
Perhaps, someone more knowledgeable could correct my misconceptions though.
If anything with mass travels faster than light, then the speed of such a particle will increase as it's energy decreases. The particle can also never slow down to less than the speed of light, as infinite energy is required to pass the barrier.
Also, if such a particle is to communicate with a slower than light particle, then it's mass has to be treated as an imaginary number.
All these things and others suggest that Tachyons are just mathematical concepts.
Think of it like the surface area of a sphere (4πr2). Mathematically this equation has two roots (r and -r) that give identical results. But this does not mean that such a sphere exists in reality that has a negative radius.
So, we have neutrinos with imaginary mass? Which brings to mind a 15 year old paper about how that might have been a possibility with the neutrino bursts from that supernova in one of the Magellanic Clouds arriving faster than expected, so this is not completely, only somewhat unexpected.
But doesn't that mean that the future is written in stone, immutable and the whole universe a timeless brick? That would mean Einstein wins in the end, because isn't that what is required to make General Relativity stay consistent? At least it would focus efforts on getting the free t variable out of Quantum Mechanics. NYAH!
The splattering you hear is "free will" philosophers brutally decelerating after they jumped out of their armchairs and through windows.
Still, my bet is that error bars will just get larger, killing off this particular weirdness.
> But doesn't that mean that the future is written in stone, immutable and the whole universe a timeless brick?
It might, unless you think of it differently and speculate that the past, present and future are in fact happening together and we lifeforms just separate it out into the three to make sense of it all (or really two, because there is no 'present'). Then the idea is that we work out the contents of our lives while at the same 'time' living it. Because how can we tell the past didn't change if we have no separate reference point outside of the flow of time? An analogy is writing a program - you run it once, it has a bug and crashes (=dies prematurely). You find the bug occurs early in the code (=childhood) and fix it, then re-run the program. The program itself never knew the original buggy code, but you are both the program and the programmer so you are both ignorant AND in control. Then you hit more bugs, and decide it's not worth fixing the program anymore because you're sick of fixing it so you just let it crash, quit and go to another company (=giving up and going to heaven? Well, it's heaven for the first few weeks at the other company anyways... :-)
A weird idea I agree, but quantum entanglement is weird like that too!
There are no serious philosophers who espouse free will- within a determinate physical universe it just doesn't make sense and by this point enough brilliant minds have failed to argue convincingly against it that people who take their philosophy seriously accept determinism.
An interesting question though - is there just one timeless brick or are there many endlessly dividing timeless bricks, intersected at certain temporal locations? In the latter case could what we perceive as free will be the decision as to which timeless brick happens to be the one we experience?
Experientially we will only know one future, so we can treat the future as absolutely fixed, but while it remains unknowable that really makes no difference to how any of us lives our life.
I think you're overreacting, Richard. I doubt whether "Einstein WRONG!!!" headlines are going to lead to mobs storming physics labs and hanging the scientists.
Einstein was wrong (by current orthodoxy) about quantum mechanics, but I never heard of any bloodletting in that debate.
Scientific laws are always subject to refinement as measurement techniques improve. A good example is the Law of Conservation of Mass. This says, for example, that if you burn 1 million carbon atoms, you combine them with 2 million oxygen atoms to produce 1 million CO2 molecules, whose mass is precisely the same as the mass of the carbon atoms and the oxygen atoms. This law was proved to be true by hundreds of experiments with different reagents and products. The mass of the products is always the same as the combined mass of the reagents, and every chemical engineer today can calculate how many tons of materials he needs to produce 100 tons of, say, sulphuric acid using the law of conservation of mass.
As measurement techniques evolved, however, it was shown that the CO2 molecule actually weighs very, very slightly less than the 3 atoms that compose it, and that the difference could be accounted for by some the mass turning into energy, explaining why burning carbon keeps us warm. The refined Law is known as the Law of Conservation of Energy, and is of great importance in theoretical chemistry/physics.
Chemical engineers, however, continue to blthely use the disproven Law of Conservation of Mass, because for everyday purposes the difference is unmeasurable.
"Einstein WRONG!!!" headlines are going to lead to mobs storming physics labs and hanging the scientists"
No the Great Unwashed won't be storming the labs, but they will use this as a way to bolster their crazy ideas.
Arguments of the form: "Well Einstein was wrong about the speed of light, so no matter what the scientists say, my theory about HAARP causing earthquakes is valid."
They don't see this as being a refinement to Einstein's models but a complete trashing of scientific knowledge.
It doesn't help that scientists hoping to make good sound bites are hyping it up with some saying this shakes fundamental science to the core.
BTW: Einstein never proved Newton was wrong for two reasons.
a) Firstly, Newton made huge disclaimers about the limits of his measurements. He said that this was the best model he could come up with and expected it to be refined in the future.
b) Newton's models still hold at low speeds. They only start to wobble at very high speeds.
I doubt even Einstein would have ever claimed he'd said the final word on the subject and he no doubt expected further refinements for cases his models did not cover.
But for the life of me, I can't even be that cynical. The masses, while unversed in the scientific method and the (hopefully) critical examination that theories go through, aren't that simple. In general, your average Joe happily accepts most scientific progress without so much as a bat of the eye. It's only when you try to violate their core beliefs (beliefs being the important word here), that they get bent out of shape. And for some (many), things like evolution or the impact of man on the global climate (for example, our dear friend Andrew O), strike them as utterly bonkers.
Because most of science is based on the null hypothesis, you do have to rely on things like probability (which even scientists have problems with) to present your case. Even a five sigma event means there is still a chance, however small, that you're being fooled by randomness or fuzziness. Therefore, most scientists qualify statements with things like "probable" or "statistically significant."
In the real world, where the rest of us mortal folk live, probable just means that you are pretty certain, such as in the law where the phrase "probable cause" is thrown around. We know of arrests, using the "probable cause" standard, that were later thrown out or resulted in the release of someone. But, because of the nature of science and not knowing everything, the shortcomings of language color the opinion of the man on the street.
But no, I don't think most people would immediately organize a book burning in the town square for all the false physics textbooks out there. In most cases, it's a failure of language and communication that causes the problem. That's why philosophers still have a use these days.
You're in luck. Einstein addressed this very question and gave a clear answer. (http://en.wikiquote.org/wiki/Talk:Albert_Einstein#Thermodynamics_.22will_never_be_overthrown.22)
Notice the particular mention of the "framework of applicability of its concepts". Presumably, then, he expected even Special Relativity to be overthrown even within the sphere for which it was developed (classical electromagnetism on a macroscopic scale).
In fact, he would probably be disappointed that it hasn't happened yet. With physics now funded on an international scale with thousands of active researchers, it is rather disappointing that the Standard Model developed in the late 1960s is still our best effort 40 years on.
Often with science articles posted here, I've wished for a reference to a corresponding technical article by the authors. Here... well... I'd *really* love to read what they themselves have to say, if it's published (though from some googling (hint: vixra.org), maybe the answer is, Not Yet, but wait for the CERN seminar on Friday 9/23...)
Are they using speed-of-light through rock and that, or actual c in the comparison?
If the former a) it has to be an estimate, so error prone, and/or b) as neutrinos don't interact much with matter, surely the vacuum c is the applicable one? Maybe this'll say something important about neutrino interactions, rather than about c....
A quick back-of-an-envelope (or rather it's modern equivelant - 8 cells in Excel) using the numbers quoted produces a figure for c that's over 56000km/s slower than in a vacuum.
Unless they can fire EM waves through 730km of rock a control isn't possible so it does seem more reasonable that the 20 parts in a million could come from an assumption made about the medium.
Only simpletons need to live in a world in which falsifiability somehow equals inadequacy. ®
I am pretty sure that the simpletons mentioned above do not understand the sentence.
It is time to make science look exciting again and take it's image out of the hands of politicians and mass media networks.
I too recall the possibility that neutrinos may have really small imaginary mass ("hi" or something like that). Not negative mass as mentioned above btw*.
So the question really is, and I am trying to visualize this right as its all quantum thingy, is the speed 'c' possible to be approached by an article with 'h'. And thus, if so, could a particle with equivilent imaginary mass thus exceed the speed of light by that same percentage. But then it would get hairy with particles that have even larger imaginary mass.***
*Which would lead to the interesting thought of a particle with negative mass actually working through a dimension backwards - would it be the time dimension?**
** And does Dark Matter have real positive, real negative, or imaginary mass or some form of mass that isnt actually described by those three planes/ummm number lines?
*** And yeah my QM was all done about 20 years ago so Ive forgotten most of what I learned back then - but I did get to do real MOSFET layouts and use SPICE (well p-spice) and stuff :)
Nothing in science is ever proved.
But the evidence for evolution is overwhelming - to the extent that it might as well be called a fact.
The main theory for the MECHANISM for evolution is modified descent by natural selection, as proposed by Darwin, modified by our knowledge of genetics, and supported by DNA and fossils. It's a good theory, and makes predictions which can be tested - google Tiktaalik for one excellent example.
The alternative theory for the mechanism is Intelligent Design, as proposed by Behe, supported by handwaving and the argument from incredulity (I don't understand how this can happen, so goddidit). It's a bad theory, which makes no testable predictions.
The necessary and sufficient prerequisites for evolution are: (1) babies are not exact clones of their parents, and (2) brothers and sisters are good at different things, which in extreme cases makes the difference between life and death. I trust that I do not need to point out examples of these in real life.
The 'flu virus is evolving all the time; which is why you need a new jab every year, so your immune system can get some practice in and learn the moves required to defeat the new version (left left up left up right down A down B down left may have worked against last year's version, but this year's version has a newer and funkier set of moves).
Identical endogenous retrovirus signatures in corresponding positions in human and chimpanzee DNA show unequivocally that both are descended from a common ancestor.
Evolution *can* happen, *does* happen and is how we got here.
On the other hand, if you think that life is complex enough to require an Intelligent Designer, then how do you account for the existence of this Intelligent Designer (who must necessarily be more complex than any other life-form, or else the Designer is redundant) in the first place?
Just because the flu virus changes from one year to the next doesn't make it evolution - it's still a flu virus after the transmutation, not a new species. Actual evolution into a new species hasn't been observed because it would take too long.
A lot of the evidence supporting evolution can also be read to support intelligent design. Imagine you're God, you come up with a design for a mammal, would you start from scratch for every other mammal you design or would you reuse the majority of the design across all your mammals?
You've got a bunch of islands that you want to put finches on, the food for these finches varies between the islands, would you design whole new finches for each island or reuse the same finch design, but change the beak to match the food source?
Most cars have fundamentally the same design, does that prove that a Ford model T evolved into a Mondeo by itself?
Blind faith in science is just as bad as blind faith in anything else.
OK, you can chose to believe that God was lazy and couldn't be arsed to finish designing finches for all the islands (which he presumable he designed himself also...., or perhaps Slarty did them for him?), so God in his infinite lazy way made a solution to allow one finch to populate all the islands.... pretty neat, go God!
As I'm tired I'm gonna go straight for the trump card in this silly game: WHO DESIGNED GOD?
"Actual evolution into a new species hasn't been observed because it would take too long"
Not true. There are several crystal clear experiments, observing evolution taking place, in a strictly controlled laboratory environment.
The problem here isn't what mass the neutrino would need in order to be able to exhibit tachyonic behaviour, that would just be work for the guys doing field theory or working on variants of the standard model. It's years since I looked at electroweak but even I can remember that mass eigenstates didn't map onto flavour eigenstates, resulting in oscillations. If one mass eigenstate was imaginary then the neutrino could be intermittently tachyonic - it's velocity switching between just below and just above 'c', without ever equalling it.
- the big problem is the potential for paradox within relativity - but paradoxes don't appear until information can travel faster than light - and a single particle burst does not constitute information.
It may turn out that any attempt to modulate the neutrino beam does not result in the information being carried faster than 'c' - group velocity doesn't have to be the same as phase velocity.
"Because it encourages a simplistic and ignorant understanding of $Topic among the general public."
Allow me to extrapolate your (precisely correct) observation into a law of society.
Regrettably too many "news" organisations use bad reporting. This is why I read El Reg almost exclusively. All the boys and Girls at Vulture Central seem more interested in telling the story than trying to rickroll us with "shock and awe".
Keep it up people!
I don't see how you disprove everything just Bamfing into existence in a suitable form, but if something with godlike powers manifested and pointed out that yes, it was all engineered that way and yes, YHBT, then evolution doesn't look quite so hot for our universe.
Doesn't answer the 'turtles all the way down' question though.
Relative to the direction that the planet is orbiting the sun, where were the two labs? Would firing neutrinos out the back at the other lab chasing after at the earth's orbital velocity account for the time difference? Late, can't be arsed to dig up formulae and crunch things.
If you fire two photons at each other, is their relative velocity twice the speed of light?
There is of course bad reporting El Reg and this whole business about misunderstanding what a scientist means when he uses the word "theory" (ie Something for which there is substantial evidence but which we must continue to "destruction test" - and indeed is formulated in such a fashion that it *can* be tested) and the way the word "theory" is used in everyday colloquial speech where it really means what a scientist means when he uses the word "hypothesis". However there are those who *deliberately* blur the differences between those two usages *and* claim that because scientists say at the outset that no theory is set in stone that shows that the theory concerned is only a hypothesis (although they use the word "theory" when making that argument). The creationists are one of the very worst examples of this kind of deliberate obfuscation using it as they do to conceal the fact that their hypothesis about the Origin is completely (as formulated) untestable and at the same time they exploit the confusion generated to claim, for example, that the theory of human evolution and creationism should have equal status in the classroom. In other words I wish it was just "simplistic and ignorant" reporters and other members of the "great unwashed" who failed to understand the concept of scientific theory, testability/falsifiability and the difference between "theory" and "hypothesis" - it is not. There are some heavyweight religious/political fundamentalists out there who deliberately run their propaganda campaigns by wilfully confusing these issues.
And neither do evolutionists.
Evolution doesn't attempt to explain the origin of life. That is outside of it's domain, a bit like Newtonian and relativity theories cover different domains. I'd be curious to know if the various parts of the theory of relativity are as mutually exclusive as the various theories of evolution.
Evolution as a theory of the origin of life is an extrapolation of "God is not needed for the variety of life forms". The belief that life started spontaneously from inorganic matter comes from the prior assumption that god doesn't exist (because he isn't needed for variety). Adding billions of years and primordial soup to the discussion waves a wand and gives the illusion that we understand what happened when in fact we don't. It is magic - technically too advanced for us to understand.
So as far as Origins go, the creationists' magic requires someone to do it and the evolutionists' magic doesn't. Either way, it's still beyond our understanding - it is still magic.
Going back to the article and falsifiability, evolution appears to be infinitely flexible in that it accommodates mutually incompatible versions of itself. Yet, whereas in the article it was noted that new theories can arise and co-exist (Newtonian and Relativity), there is no possibility of an acceptable additional theory of life, even though there are admittedly significant problems with incomplete and contradictory evidence and incredibly unlikely assumptions.
It's a bit of a jump from "a set of commonly held working assumptions based on an interpretation of the evidence" to "it's as factual as 1+1=2".
Perhaps if it's adherents were a little less dogmatic...
I am deeply humbled that you would place mine, and everybody else's ability to understand something on the same lofty plane as your own.
One thing I can understand though, is that a post about evolution has little to do with CERN neutrino results.
Does this tie in with the observation that neutrino bursts from distant supernova appear to arrive 20 minutes prior to the visual confirmation? Is this the right time difference to match the experiment? (Previously explained as "dust" interactions.)
As neutrinos notoriously don't interact much, could this be something to do with the virtual particle creation/destruction in transit.
The difference in hours is explainable in core-collapse supernovae, because light gets absorbed and re-emitted many times before reaching the surface, whereas neutrino zip through the dense core matter. The currently observed effect would result in 4 years difference even in a nearby SN in the Large Magellanic Cloud.
Don't let BT hear about firing broadband through rock, it would be the ideal traffic shaping. Downloaded too many torrents this month? Granite for you! Been relatively good? Switch to limestone.
The worst thing about bad reporting on science is how smug all the headlines look. Einstein wrong in 6 inch letters? Must be true then. Off to read the Daily Fail to see how they explain it to the common people.
"Off to read the Daily Fail to see how they explain it to the common people."
Headline: "Neutrinos Travel At Faster Than Speed Of Light After Gypsies Steal Them"
Sub-headline: "Jew Gets Laws Of Universe Wrong, Should Probably Stick To Eating Christian Babies"
Editorial: "We at the Daily Mail always knew that things could travel faster than light. Among the objects we have personally observed going faster than a neutrino: our judgement (when travelling out of the window), our knee tendons (when oscillating after seeing a photo of a junior martial arts contest), and human drool (coming out of our mouths while taking photos of celebrities in swimsuits, preferably underage)"
Tachyons are mathematical concepts. It is effectively just rearranging, and taking the other root of the E=mc2 equation.
Think of it like the surface area of a sphere (4πr2). Mathematically this equation has two roots (r and -r). But this does not mean that such a sphere exists in reality that has a negative radius.
"I believe they are measuring it with GPS"
That's a *very* good point.
IIRC Civilian GPS is only good to 30m (1 arc second of the Earth's circumference).
However according to this link
Modern civilian GPS 2 frequency receivers should be able to get to withing 5m.
There are daylight surveying telescope systems that can triangulate against stars to <6m (which given the error levels we're dealing with might be a good idea).
Neutrinos *possibly* 60ns FTL.
Podcast and wire service reports.
Cosmic rays interaction with Earths atmosphere *radically* changing levels of cloud formation.
"We must avoid interpreting these results".
They are *both* interesting and both, if confirmed require *substantial* revisions to cherished theories.
So why the different treatment?
well, i dont have a clue about all this, but its most intresting :)
What i dont understand is that we have all these "laws" which have stood true for the last 100 years, but my problem is the question of why? why cant something be done, why does something have to follow these rules, who is to say that these laws are perfect.
Essentially, we made up these rules based on our understandings, but why do they have to be correct, because we say so?
but anyhow, thats just my ignorance of the situation, but id love for someone to tell me why these laws must hold true without resorting to quoting the laws them selves.
perhaps im talking out of my arse but ive just never understood why we say something cant be when equally we dont know everything.
Science is the pursuit of knowledge and understanding based upon evidence.
It doesn't claim to have all the answers. For example, Quantum Mechanics and Relativity are mutually incompatible - they can't both be exactly correct. That's not the point however. Both are exceptionally good models for the domains they attempt to represent - that is to say they enable very accurate predictions of events and behaviours that experiments can then show to happen. The same is entirely true of Newton's Laws of Motion.
The practical difference between Relativity and Newton's Laws is that if you want to play pool, or build a roller-coaster, Newton is fine and Relativity unbelievably over-complex, but if you want your GPS to work, you'd better use Relativity.
Alternatively, we know, for certain, that Newton's Laws are incorrect - there are situations that we can observe and measure that demonstrate this. Doesn' t mean we throw them in the bin, they happen to be exceptionally useful and for most of us, most of the time, they're so close that it really does make no difference at all.
You'll rarely hear a serious scientist say anything like "Relativity is True", you're much more likely to hear "Relativity is proving to be a remarkably robust theory." meaning that experiments consistently and to great accuracy validate it. It only takes one experiment to prove it "wrong" but over time, as more and more observations of the universe are made that continue to support the theory, more confidence grows that "there's something in it" even if it's not actually correct. And regardless, it *is* useful.
Your problem is the English language - we often use the same word for different ideas, and this can cause confusion. In this case, the word is "law".
In science, a law is not a rule that you can't break, it's an observed reality that has been recorded many times and hasn't been refuted by any other observation. Gravity is a fundamental example. When you drop something, you expect it to go "downwards". If it goes upwards, you look for an explanation, because it "breaks the law" which says "what is unsupported must move down".
Once it was generally understood that the world was a sphere, (long before the Christian era), the word "down" in the law had to be modified to "towards the centre of the Earth". Newton's mind-shattering insight was in realising that gravity was was a universal property of mass, but that the Earth was so massive that its gravitational effect drowned out the effects of other nearby masses. As such, he developed a new version of the "law of gravity", and a "theory of gravity" to explain it.
You can argue with Newton's theory of gravity by proposing an alternative theory which explains Newtons law of gravity equally well, but you cannot argue with Newton's law of gravity except by finding a circumstance in which it isn't true.
I hope this helps.
WHst the speed of neuteno's thru a vacum? Also rotational speed of the planet and lets ignore the aspect that the earth is orbiting a sun at speed.
Have these two aspects been factored in. Until we see a light particle and neuteno travel from point A to B and the neutreno gets there first; Until then there will be some doubts. Still fun times.
Does that mean we can stop all this silliness about "Dark Energy" and "Dark matter". If the C in E = MC squared is a smidgen bigger doesn't that account for the missing mass/energy? Or at least some of it? Or is it just hiding in another dimension through which neutrinos move?
Mine's the one with an alternative universe in the pockets.
Lasers are light and we already know the speed of light. Even if things can go faster than the speed of light how does that affect lasers? I'm shocked at a lot of peoples attitude about the whole thing its also like no body can question the Theory of Relativity. Isn't science all about advancing theories or expanding on them? Its almost like people are frightened about something changing the laws of physics.So just because the theory of relativity for the most part works should never question it or try to expand on it?
If we, as a species, feel that we "know it all", and that our "currently established laws" somehow describe the totality and that then allows us to make sweeping statements about what is and what is not possible then we are, as my title suggests, children.
Keep asking the questions...
Our fire has become our electricity...what will our electricity become?
It might not sound like a big discrepancy, but as an example, for this to have been caused by a physical calibration issue the equipment at each end of the experiment would have to have been about 14.5 meters further apart than the scientists believed...
Now we just need them to discover the Higgs boson and we can have FTL star ships with on board gravity field generators :oD
...the next day, the boffins recieved letter from the Universe's Safety Camera Partnership demaining a £30 trillion fine, and three points on their science licence. It turns out when people said light was the universal speed limit, it was only the fear of the fine that kept that in check.
Neutrinos: the boy racers of the subatomic world!
I can think of loads of possible reasons, none of which violate relativity, interesting as they are:
1) How did they measure the distance between the endpoints, and exchange time? The only method that could be remotely accurate enough, is GPS. Which fundamentally clocks photons to orbit & back. So, what they are basically saying, is that the photon-exchanged space-time separation that they measure is actually ~20 cm too short.
A) The GPS constellation was never designed for that type of measurement. Differential distances of a few mm, yes. Over that distance, no.
B) GPS was designed to compensate for General Rel, and the time-lag of the radio through the air (differential of two frequencies). But never the ABSOLUTE time-value. How could it? Light doesn't travel through air at the same speed as light in a vacuum
2) Neutrinos travel faster than light. Maybe (if they put the effort in to remove all systematics, which I doubt is possible). But that doesn't tell us that special rel is dead, it would tell us that photons travel slower than "the speed of light"."The speed of light", is properly just the meaningless conversion factor between space & time. So if photons don't travel at the speed of light, that is very radical, and very interesting about Quantum Electrodynamics. But not special rel.
3) Lots of things travel faster than light actually. See, for example tunnelling electrons. But INFORMATION can't. The "trick", usually, is that some physical effect causes us to preferentially detect the leading-edge of a spread-out wave. That can either be a detector effect. Or, in the case of tunnelling electrons, the probability of transmission is 0.01%, but those electrons that do make it through are "instantaneous". After a lot of numerical magic, it turns out that if one treats them as information channels, and modulate information onto them, the average speed of information is slower than light.
Probably the most likely, because the cross-section of neutrino detection is so fantastically small. Measuring the timing of the peak, when the detected distribution is 10^-15 of the actual flow, is a mugs game in terms of detector dynamics to be honest. The assumptions one would have to make about how symmetric the distribution is....
4) Detector dynamics. What exactly do we know about the timing of neutrino reactions? Any non-prompt or nonlinear processes? Remember, what we detect is the light given off when the neutrino interacts - not the arrival of the neutrino itself. And how big is that detector? 12 meters, just and they would like to tell us about the accuracy arrival time to within 20cm?
So much for predictions that we will understand all of physics in a decade or so!
Since some neutrinos appear to have mass, going this fast implies that Special Relativity got it wrong anyway, since the effective mass of the particles would be infinite under that theory. I'm going to bet that only one of the neutrino types does the hyperspace thing, though. Maybe one of the oscillation states is the so-called sterile neutrino, which doesn't interact because it has crossed the light-speed barrier.
Any way you look at it, neutrinos really change the ground rules.
I'm guessing Fermilab and SLAC just got a major life extension!
"So much for predictions that we will understand all of physics in a decade or so!"
It is sadly true that various fairly eminent souls have made several such rash claims over the past hundred years, but I don't think it has *ever* been the consensus view of physicists.
And as I noted in a reply to an earlier post, Einstein held precisely the opposite view (i.e., that we'd never finish) except for the special case of classical thermodynamics, which in many ways is a set of theorems about inference from limited information rather than an actual physical theory.
This has always bugged me, if a unit is travelling at say 700 miles per hour and fires a bullet, then the speed is 1,400 MPH, the same thing if you are travelling at the speed of light and fire a rocket again in the direction of travel then surely the rocket will be travelling at more than the spped of light, however, relative to what?
I asked my physics master that some 50 years ago and he could not answer it. If a space ship at speed of light transmits a radio message, is the message standing still as perceived from behind and travelling at 2 times the speed of light in front.
Surely the speed is relative to the item that it is related to, otherwise me and my car can be "done" for 30,000mph as the whole earth is travelling at that speed.
So are we looking at 2 things separatley but together.
If the neutron was fired at the speed of light from something travelling at the speed of light then in relationship to the original source its 2x the speed.
No one has denied nor confirmed this, if it is not so then jet planes that broke the sound barrier and having machine guns would have shot themeselves down as the bullet would be going backwards relative to the plane, but they were not, they were travelling at mac1.5.
If you are travelling at half the speed of a bullet and you measure a bullet going past you it looks like it is going half the speed of the bullet.
If you are travelling at half the speed of light and you measure a beam of light going past you it looks like it is STILL going at the speed of light, not half the speed.
It is this behaviour of light - that it does not behave like bullets - that gives rise to relativity - something has to give and that something is TIME (simplifying a bit here).
First off, your 700+700 actually works out at marginally less than 1400, but the margin is too small for anyone to notice.
Secondly, your stationary observer standing behind the spaceship sees the radio wave move at exactly x and the radio operator on the spaceship does too, despite the two observers *agreeing* that they are moving relative to each other.
Now, if you want to turn round and say "This cannot be. I cannot imagine definitions of space and time where this is even possible. It must be untrue." then well done. You've arrived at roughly where Einstein started off. His conclusion was that in order to preserve the constancy of c, he would have to change his definition of space and time.
To be honest, if trying to imagine space-time doesn't do your head in, you haven't understood it. I find quantum theory *much* more acceptable.
"I asked my physics master that some 50 years ago and he could not answer it."
This sort of question is now well within the realm of ordinary physics teachers now, because there has been enough time for teaching methods, analogies, and explanations to catch up with these complex ideas.
The speed of light is the same for observers on the unit, or on the ground that it is approaching.
If you are on the unit, then from your frame of reference the unit will not be travelling at all, and it is perfectly acceptable to fire a beam and have it shoot away from you at the speed of light.
If you are on the ground and a unit approaches you at the speed of light and fires off a beam toward you then you will see them simultaneously because the beam and the unit are both travelling at the same speed - the speed of light - from your frame of reference.
The thing you will both agree on is that the beam travels at the speed of light. The thing that you will not agree on is the time when it was fired.
Came across this a few weeks ago, researching DNS stuff and Anycast. Apparently the pings were coming back before they had sent them from the servers on the other side of the world. I really can't remember now and I didn't bookmark it. It was really weird off the wall stuff that, to be honest was well over my head on more than one level. So don't quote me on that, but please do correct me if you know what I'm talking about (because I don't). Maybe it was all just a dream.
Here's a few links, however:
Really sorry I didn't bookmark it now.
How the elapsed time is measured?
What I mean is:
a. I believe from the reports that the distance travelled by the neutrino's is 454km (or it might have been miles) from CERN to some other lab.
b. Clearly, if I call you 454km away and say "synchronise watches!" then the result is garbage because of the time delay inherent in the phone conversation
c. If you came over to see me and we synchronised two atomic clocks then you drove away with one, how do we verify that they have remained synchronised?
d. Use of something like timeservers wouldn't work simply because of the minute variance inherent in the network connections etc
Surely the most accurate way of timing this is for the neutrino's journey to start and end at the same point, ensuring timing by the same device? It wouldn't appear difficult to be more than 50 billionths of a second out otherwise.
Awesome discovery if it's true.
Could this effect not be explained in the same way as Hawking radiation (predicted and observed) which escapes a black hole (not even 'light' can escape a black hole) using quantum mechanics?
or the less fun version: the detector is based near the L'Aquila earthquake of 06/04/2009. This could of damaged there equipment giving a small systematic bias on the readings.
@Roger Mew this is explained nicely in a book by Roger Penrose called: The Emperor's New Mind
Hawking radiation doesn't escape a black hole, not in the sense of something that was once inside getting outside.
Hawking radiation is the case of virtual particles being created spontaneously near the event horizon. One is slightly on the outside and shoots out into space, free from its partner, while the other is slightly on the inside and shoots inwards, colliding with something and taking them both out of existence.
And, sorry, it's "could have" not "could of".
The evidence seems to contradict the laws of physics. It takes 32ms for a photon traveling at the speed of light to bounce from the U.S. Northeast to the West Coast and back again; in practice you're doing extremely well if you can get through all the routers in twice that (for example my DC and CA computers have a 94ms ping time between them). But 3+13=16ms is much less than 32ms and a physical impossibility. Even with perfect zero latency routers and perfectly straight-line optical paths, a 16ms round-trip is twice as fast as possible.
Still confused though.
assuming for a second that this is indeed true, that we have neutrino's traveling faster then the speed of light in vacuum.
I'm willing to bet, assuming this is not a meaurement error, that this will eventually be shown to be caused by the fact that the Higgs field (which we dont even know yet exists :) ) exists, and is not constant.
Any phycisists in the house willing to correct me on this ?
very tight.... very very tight, between Geneva and Gran Sasso (thru a tunnel!). Now when Bob in Geneva pulls on his end, does not the string tied around Alice's wrist in Gran Sasso not tug immediately, nay instantaineously?
Using a piece of string and Morse code you can therfore send information faster than light AND neutrinos, hay presto!
Reply appreciated, however I still find it hard to grasp from a "gut feeling" point of view. I have puzzled over this one for years with physicist offering various "train-car" analogies. Are you telling me that for a 330m* piece of (tight) string if I pull one end the other end doesn't move until a second later???
[*speed of sound in air, presumably faster in string]
Mind boggling!!!! (and hard to accept). What if I pulled on the string at faster than the speed of sound in the string?
Finally, please see title!
Correct if that's the speed of sound in whatever medium.
That answers both questions.
(should be easy enough try with string - not sure about the neutron star rod)
"What if I pulled on the string at faster than the speed of sound in the string?" - I think you might snap the string.
Common sense or "gut feeling" is not always a good guide to reality. To some extent that's why we need mathematics. Try reading about chaos theory which doesn't deal with the very small like QM or the very fast/large like relativity but still provides some really weird and wonderful effects in the everyday world.
"What if I pulled on the string at faster than the speed of sound in the string?"
That will generate a shock wave which will initially travel supersonically until its energy is dissipated enough and then it will convert into an ordinary wave. It may or may not break the string depending on the stresses produced and the strength of the string.
Is this the same cern who have a big bug in there software?
Anyhow ill wait and see, and as im inpatient, if time travel ever becomes possible. either ill come back and stop myself or can someone post before me not to :P
If this post is readable bad news time travel will never be discovered, but things might still travel faster than light, although how moving fast is of any real benefit to mankind right now, i dont know.
Also id like to remind myself next week to buy a brolly, buy shares in some cern.
But note a few things.
Firstly while neutrinos have *little* interaction with matter they do have some. How could you detect them otherwise?
So unless that 730Km path is *very* homogeneous or *very* well mapped regarding its physical properties a vein of the right material (I'll guess something of below average density but IDK) could probably give this.
It also appear impossible to run a parallel light beam through an evacuated tunnel due to the engineering problems. This would be the ideal race. Obviously the beam pointing issues would be severe. IIRC the JPL did work on laser comms from Mars to Earth and developed systems that can deliver nano radian pointing accuracy for all you armchair physicists.
*if* this can be duplicated (no reason to think it cannot but it's always nicer to have confirmation) and these neutrinos have exceeded the speed of light in a *vacuum* (once the *know* corrections for it being through rock are made, both important words in this context) then a fundamental principle on which large chunks of modern physics is based is going to need some serious re-thinking.
Of course the *ultimate* test of this is to send the neutrinos through a vacuum path, requiring *no* corrections for media. That's likely to take a long time to do but with this result it should have it's priority raised substantially.
Exciting times. Who saw this one coming?
"...why has EVERY post on this thread (including all replies) been downvoted at least once?"
Good question. I noticed all my posts had down voted but not realised it had happened to *everyone*.
Trial of mass down/up voting mod gone wrong?
General snarkyness of a poster?
Who can say.
So ... five pages of posts, and only one mentions causality?
The biggest issue with FTL neutrinos isn't the asymptotic increase in relativistic mass. It's not finding a new area of post-Einsteinian physics (pace Robert Chirgwin). It's that a controllable, detectable neutrino beam - which is at the heart of this experiment - which is FTL is a signal; and that means transmitting information faster than c.
And if you can transmit information faster than c, you can send a signal from an event to an observer who precedes and can affect that event. And thus you can create temporal paradoxes, and causality goes out the window.
The article Chirgwin linked to has a basic explanation, though the accompanying light-cone diagrams aren't great.
As one commentator did point out, previous claims about other FTL information transmission (eg the Bell effect and the EPR paradox) have been revealed as non-issues, because no information is exchanged. At the moment, these results - if they stand - look different. And there doesn't yet seem to be any explanation of how we salvage causality if they are.
"And if you can transmit information faster than c, you can send a signal from an event to an observer who precedes and can affect that event"
Aren't these two different things? Sending a message FTL and sending a message back in time?
FTL does not necessarily mean "to the past", it just means "bloody quickly"...
If you can send a signal FTL, you *can* send a message to the past (speaking loosely - I'm not going to try to draw ASCII-art light-cones here). It doesn't matter whether someone actually does.
Here's a simple thought experiment. Set up a couple of these detectable FTL neutrino beams in appropriate frames of reference, so you have a full-duplex link between two sites. Now it's not hard to arrange things so that a signal from A to B is bounced back from B to A; and when it arrives at A, it disables the emitter there. And since these signals are FTL, you can arrange for the B-A signal to arrive before the A-B signal is generated.
And thus you have a paradox: if the signal is sent, the signal is never sent.
Again, it doesn't matter whether anyone actually *builds* such an apparatus. If they *can build* one, then we have a problem: inconsistent causation. There are all sorts of science-fictional ways to weasel out of this (one favorite is the "robust universe" model, where random accidents just prevent a paradox from occurring - eg your equipment breaks down at a crucial moment), but it remains a rather nasty metaphysical problem.
The neutrinos that do not change flavor travel AT the speed of light. The neutrinos that CHANGE flavor leap ahead by a Plank Length because during the change of flavor there is a Virtual Particle change that lets the new flavor leave the change area at the same time the old flavor reaches the change area. http://en.wikipedia.org/wiki/Virtual_particle
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