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Faster-Than-Light Particle Results To Be Re-Tested
surewouldoutlaw writes "After the astonishing news from CERN that the OPERA experiment had detected neutrinos traveling faster than light speed, challenging Einstein's theory of special relativity, there has been some skepticism over the results. Now Fermilab, near Chicago, has announced it will attempt to replicate the experimental results within four to six months."
And I posted it tomorrow, as well!
So if we don't get the results by next month, we can assume the experiments failed to hold up?
If you didn't see this coming, then you don't understand science...
WARNING! This girl exceeds the MAXIMUM SAFE standards established by the FDA for BRATTINESS
The results are in!
The barkeep says 'We don't serve faster-than-light particles in here'. A neutrino walks into a bar.
Confirmation of the results of an experiment by an independent party is standard practice in the scientific community. Without it, the findings wouldn't even be considered completely valid! Nothing to see here...
They already did the experiment, and actually found similar results but did not claim any significance. Of course they are going to repeat this, once they finish kicking themselves.
...if the Neutrino was a filthy cheat running a hidden nitrous bottle.
"When information is power, privacy is freedom" - Jah-Wren Ryel
The process is working.
The scientists at CERN asked for peer review and checking of their methodology. This announcement means that at least on paper the method was near-perfect for Fermilab to be committing resources in the near future to prove/disprove it.
Science: it works, bitches!
http://xkcd.com/54/
I did have a college physics covering relativity but it was a long time ago. Correct me if I am wrong, but Einsteins Special Relativity theory doesn't prohibit speeds faster than light. It just prohibits speeds EQUAL to the speed of light. If so, It would be problematic to accelerate past the speed pf light or to decelerate to slower than the speed of light.
And re-tested and re-tested and re-tested.
Could you elaborate, please?
Having neutrinos fly at 'true c' rather than a lower 'apparent c' isn't a good solution, because it doesn't take in account neutrino bursts from supernova 1987A. The neutrinos from that supernova were detected only four hours before the light from it. That's explainable with what we know about internal stellar processes. But if the neutrinos were flying FTL then they should have arrived four years earlier.
The most likely explanation for the CERN results (apart from experimental error) is that neutrinos are tachyonic -- they have imaginary mass, and naturally fly faster than light. The higher their energy, the closer to lightspeed they travel.
That's not a trivial situation. To use a technical term, it breaks relativity into itty bitty pieces. We will have to change a lot of theories around. But it's unlikely that the value of c is going to change.
Genocide Man -- Life is funny. Death is funnier. Mass murder can be hilarious.
Six if they don't. ;)
I talk about stuff.
OPERA has just found that either neutrinos travel 0.03% faster than photons we've measured, or their equipment has an unknown systematic error. Assuming there's no equipment error, I would find it more palatable to assume that light around Earth travels a bit below c and that neutrinos travel closer to c. What we think of as vacuum could really be a medium with refractive index 1.0003, perhaps due to a uniform background of weakly-interacting particles (maybe even dark matter) that affect photons but not neutrinos.
I have a physics undergrad degree; if there's someone here with better qualifications, would you care to weigh in on the idea that c could be 0.03% faster than the speed of light we measure on Earth?
Expected time to finish is 1 hour and 60 minutes.
Random question:
What kind of technology and materials would we need to get the giant Fermilab etc. down from square kilometres down to square metres or even inches? Would cheap fusion energy, or room-temperature super-conductors, or limitless supplies of carbon nanotubes/diamond/graphene help reach that particular goal?
Why OpalCalc is the best Windows calc
I think they're more interested in what could be slowing down the rest of the universe and NOT neutrinos.
Sorry guys. I'm not trying to put him down but Phil really isn't the one we should be turning to on this question. While he brings up good and valid points the bottom line is that he even said in his twitter feed that this isn't his area to speak on. I respect the man for his work with BA and in the community in general but he's just not the best source of understaing on the subject. Something tells me that better sources for information on this are keeping their mouths closed for a good reason even if it's nothing more than professionalism on their part.
I want a neutrinos modem so that my downloads are finished before I click on the links!
If they can go faster than light, then they may have already completed their retest. The results of that test were that they cannot go faster than light.
Again, don't the neutrinos arriving before the light from SN1987A simply mean that the neutrinos got here at closer to c than the actual light?
I mean the light from SN1987A had to travel through a non-vacuum (space, which is never really empty) and the neutrinos on the other hand were simply less obstructed.
I don't know the meaning of the word 'don't' - J
The theory of Relativity still holds true, what this experiment (if it's accurate) changes is our idea of matter and causality: if neutrinos have imaginary mass, they are allowed to traver faster than light, as tachyons; and causality may have to be revised, from a onward moving arrow to a regular dimension, in which the future can influence the past.
http://www.gizmodo.com.au/2011/09/nikola-tesla-predicted-faster-than-light-particles-in-1932/
If they succeed in recreating the measurements, doesn't it just mean that c was set at too low a value, and that the true speed to light in a vacuum is slightly faster than originally thought?
c is not a fundamental value, its a function of the permeability and permittivity of either empty space or some dielectric (something like inside a piece of coaxial cable, etc). Or rephrased, you are arguing the impedance of free space is wrong, and generations of antenna and RF engineers would disagree with you. Also c shows up in energy mass equivalance e=mc2 and all that which seems quite accurate. And in time dilation experiments it seems to work quite well. Astrophysics "stuff" thats far away seems to confirm that neutrinos do not exceed light speed in vacuum; this test involved blasting thru rock instead of vacuum so that is no huge problem; theres a long history of shoving light thru materials results in weird behavior. Given how many decimal places that kind of stuff has been verified, more than this result which was only 6 sigma or whatever, I'm thinking fundamental constant fine tuning is awful unlikely.
In summary, either its wrong (which seems unlikely given all the verification they did) or its new physics. Simply tuning up the known constants is just not gonna work.
To fit other, higher precision experiments, its gotta boil down to something like the logical inverse of the light refraction law, where light slows down in certain materials (like, say, glass) resulting in refraction and timing issues (like pulse dispersion in optical fiber). The analogy is maybe neutrinos "speed up" when rammed thru solid rock due to some strange property of rocks, or floating about in a rock-produced gravity well, or something like that.
I can totally see how previous subatomic experiments would miss the neutrino effect; after all its hard to shove gammas or plain ole light quanta thru a couple zillion KM of solid rock... Its too technologically hard to do, until trying out the neutrinos...
A good example of how F-ing around in the lab doing blue sky stuff simply because you can, is the primary source of interesting ideas.
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
Because relativity starts to break down when things exceed the speed of light.
Wikipedia sez that going faster than the speed of light breaks causality -- so signals can be received before they're sent. However, as you suggest there is plenty of room to rework the theory rather than throwing up our hands and declaring reality broken.
-GiH
I can only assume that they've corrected for General Relativity. Everyone seems to be pointing to the obvious potential sources of error: knowing when the neutrinos are created, knowing when they arrive, knowing the distance that they've traveled.
What about variations in the Earth's gravitational field between the two clocks? Or along the path that the neutrinos follow? You can't call the planet a point-source of gravity - the density of matter is quite lumpy.
I haven't seen a back-of-the-envelope calculation for this...maybe it's orders of magnitudes impossible? Would it require a tiny black hole to throw the timing off by 60ns...or would a big uranium deposit be enough? I could probably do the Lorenz transforms for Special Relativity myself, but General is a bit beyond me!
1. Yes, due to relativistic addition of velocity, neither see the other as moving over c.
2. This does not transmit information faster than light, and
3. The shockwave of you pushing the rod would propgate at the speed of sound in the material, not instantly. Until it reached the end, the rod would effectively be 1/16th of a centimeter shorter.
It's not so simple. We've measured the speed of light to great precision. We know what that speed is, and we know photons are massless, so we know with very high confidence what the speed of massless particles is. If neutrinos travel faster than light, then this is very surprising and points to something new and interesting. I'm avoiding referring to 'c' because it would be ambiguous: in traditional relativity, the constant speed of light is equal to the maximum possible speed, which is also in essence the ratio between space-like and time-like variables in the theory (the slope of light-cones and all that). It's a constant that reappears over and over again, and marvelously it's precisely equal to the speed of light. It can't be as simple as just "we were wrong, c is a bit higher than we thought" because it would immediately mean that "c" isn't as universal as we thought: the symmetry of the universe must be somehow different so that photons and neutrinos (and probably other particles) follow slightly different rules.
But if this result is indeed true, and neutrinos travel faster than light, then this is truly amazing and could mean different things. One possibility is that different particles actually have different 'speed limits' (and different causal cones), so there is c_light, c_neutrinos, etc. There are many other possibilities (extra dimensions, breaking of Lorentz invariance, imaginary mass, closed timelike curves, etc.). All of them amount to a substantial rethinking to some aspect of physics. This is definitely exciting, since it could be telling us something very new! And it won't be as simple as just adjusting a constant a bit. (If we tweak the value of "c" in our equations even just a bit, all kinds of well-tested observations, in everything from cosmology to the functioning of transistors, would come out wrong...).
Lastly, it's worth keeping in mind that it's probably a subtle experimental error (very subtle!). This is still useful, because it will teach us something new about experiment design and possibly even teach us something about particle physics. For instance, the timing calculation is based on certain models of the packet of neutrinos that are generated. But, it could be that the packet that arrives at the end is slightly different than the one sent out at the beginning, thus altering the way one should compute the flight time. This could point to some interesting, previously unknown, ways in which neutrinos are generated, or interact with matter, or interact with each other. In any case it will be interesting.
1. Yes, they can see each other. Why should they not? You can hear a fighter jet flying faster than the speed of sound easily, similar here. But don't get confused: you will only ever be able to see the past "image" of the other object, this image is traveling towards you with c.
2. More than 1 year. Your idea of a rod is not quite right. Think of it like a big rubber band, then make it stiffer and stiffer. If you pull too hard you would rip off one end but in any case they would probably not notice it for way more than a year (speed of sound).
...ago, of course.
Thanks for taking the time to reply, vim.
Why can't c be just slightly faster than it has been estimated at?
I mean no one has ever been able to measure the speed of light in a true vacuum, right? A true vacuum would contain absolutely no particles and no electromagnetic waves. That is impossible to obtain, so how does anyone really know how fast c really is?
Maybe neutrinos are simply lithe enough that they are almost unaffected by the non-vacuum, I mean it has been theorized that to completely block a neutrino, you'd need a block of lead one light-year thick.
I don't know the meaning of the word 'don't' - J
object A moving .50001 the speed of light. Object B moving .5 the speed of light moving the exact opposite direction away from object A.
You are on object A, can you see object B?
Yes.
I thought they already figured out faster than light speed via quantum physics entanglement.
No.
Another thought experiment. a 1" rod 1 light year long. you move it 1/16 of a centimeter. How long does it take for the movement to register at the other end?
A: its instant, for it does not need to move any faster than the time it took you to move it.
No.
A million internet points for the person who commercializes this in to a faster than light inter-planatary communication network and calls it subspace.
3e8 is here to stay in my dungeon
There is no way I am relearning electronics math after replacing 3e8 -- with what? , a new unknown variable!?
Radios and TV's will be fixed with existing 3e8 test equipment and 3e8 math.
I'll make a prediction, even if there is a particle traveling faster than 3e8,
it will be a particle which people who work with 3e8
1. don't care about, unless the discussion is shielding
2. can't measure
3. can't use
4. the timing for chips will still be timing for chips based on 3e8
5. Joe 6 Pack will be hard pressed to put a particle going faster than 3e8 to practical use
3e8 is here to stay, it's the LAW for now.
object A moving .50001 the speed of light. Object B moving .5 the speed of light moving the exact opposite direction away from object A.
You are on object A, can you see object B?
I thought they already figured out faster than light speed via quantum physics entanglement.
Another thought experiment. a 1" rod 1 light year long. you move it 1/16 of a centimeter. How long does it take for the movement to register at the other end?
A: its instant, for it does not need to move any faster than the time it took you to move it.
My understanding is that object B is outside the light cone and therefore is not observable from object A and visa-versa.
The rod would not move instantaneously, the movement of the rod would be transmitted from one end to the other at around the speed of sound in the material. IANAP But I guess this means it would either take a lot longer than a year to move that far (because the inertia would be so huge and waiting for the other end to start moving) or you would send a compression wave from one end of the rod to another.
1. Yes, drastically red shifted.
2. What's the bar made of? It would have to be pure Imaginanium and impossibly rigid. Any other material? Then the movement propagates depending upon the modulus of elasticity- or the propagation of electromagnetic force between atoms. Even your two foot long one inch rod of diamond compresses a little when you push one end.
To a neutrino, space and the planet Earth are almost equally transparent. The neutrinos from OPERA and the neutrinos from SN1987A should be travelling at the same c, and they (apparently) aren't.
The one real difference is that the planet has a gravitational field. That could support some theories which suggest that neutrinos are able to take shortcuts through extra dimensions, but only in the presence of a gravity field. That result would still make relativity choke and turn blue, but it might make sense.
Either way, it doesn't look like a tweaking of the value of c is likely.
Genocide Man -- Life is funny. Death is funnier. Mass murder can be hilarious.
with v > C
I don't know about Tesla, but this is Yet Another Example... Of the standard scientific method.
You never trust a single result, the experiment always has to be repeated especially in the case of unexpected findings. What I'm really waiting for is data from other accelerators, or experiments (given this experiment may be prohibitively difficult to properly replicate) to corroborate the findings.
I'm not even remotely qualified to comment on this, but I seem to remember light being affected by gravity and thus the mass around it, where as neutrinos are virtually unaffected by normal matter. What this says to me is the neutrinos are showing us what the actual speed limit of the universe is compared to what we think it should be as an observer sitting on a giant ball of gravity rich mass. Basically, in space, they go the same speed, which is why the neutrinos and photons from a distant stellar event show up here at the same time, but on earth, the results might be slightly different.
My gut tells me that this will end up shoring up special relativity and perhaps adding a new understanding of our universe without shattering everything as so many are saying.
object A moving .50001 the speed of light. Object B moving .5 the speed of light moving the exact opposite direction away from object A.
You are on object A, can you see object B?
I am not a physicist by any means but...
Einsten told us that to add two velocities u and v the right formula is (u+v)/(1+(uv/c^2)). In your case this yields 1.00001c/(1+0.250005) =0.8c.
I thought they already figured out faster than light speed via quantum physics entanglement.
They did not. You generate the entangled particles together, you take them to different places, you read them and you see the same quantum state. After that the game is over. You cannot change the state of one expecting the other one to follow.
Another thought experiment. a 1" rod 1 light year long. you move it 1/16 of a centimeter. How long does it take for the movement to register at the other end? A: its instant, for it does not need to move any faster than the time it took you to move it.
If your rod is made out of a perfectly rigid material (unobtainium), that will work. Interactions among atoms are of electromagnetic nature and you stil have propagation of information at the speed of light
If they succeed in recreating the measurements, doesn't it just mean that c was set at too low a value, and that the true speed to light in a vacuum is slightly faster than originally thought?
No, probably not. Einstein came up with relativity after a thought experiment concerning what a light wave would look like if you were traveling at its velocity. Electro-magnetisim does not allow for a stationary vacuum solution, so he figured out that the way out was to have time stopped at the speed of light. If the speed of light isn't the speed of light, this problem reoccurs. Now, you could postulate a material (let's call it the... ether), so that light is traveling slow, while neutrino's bound on ahead, but that also would disagree with various experiments.
One way out is to have the neutrinos be tachyons, traveling faster than light, but that does allow for causality violations. (Read the link.) That is based on pretty basic stuff, so it's hard to escape it. That would trouble a lot of people, but it would allow for neutrino oscillations (changes from one type to another). You can't do that at the speed of light, as time is frozen there. (As oscillations have been observed, that is additional strong evidence that the neutrino velocity is not the new "speed of light.")
And, there is also the Supernova 1987a results, which conflict with these results (as the 1987A neutrinos do travel near c). Maybe there are oscillations between tachyonic neutrinos and non-tachyonic ones, which would be mind-blowing all by itself.
I think that a bunch of theorists will spin their wheels until this is better constrained experimentally.
With the small but consistent error in the results, what I have not seen is how you know that this isn't a measurement that the distance did not change.
You are wrong on both counts.
In the first example, Galilean relativity (velocities sum) is not correct at high velocities.
In the second example, objects are not perfectly rigid, the movement actually travels at the speed of sound in that medium. So much slower than light.
You are on object A, can you see object B?
Yes, although it will be heavily redshifted.
The most likely explanation for the CERN results (apart from experimental error) is that neutrinos are tachyonic -- they have imaginary mass, and naturally fly faster than light. The higher their energy, the closer to lightspeed they travel.
This would be backwards. SN1987A neutrinos were in the 10MeV range so should be much more super-luminal than the 17GeV neutrinos being measured at CERN. So I think that rules out tachyonic neutrinos.
Assuming that this is a real result, the most likely explanation is going to be the emergence of new physics when KE is very much (10^10 times) greater than rest mass.
Some sort of frame dragging a la alcubierre drive would be one possibility that possibly doesn't have to throw out relativity.
Tim.
God said, "div D = rho, div B = 0, curl E = -@B/@t, curl H = J + @D/@t," and there was light.
As the underground tunnel between Swiss and Italy is not finished yet.
Indeed.
Sent as ripples into the electromagnetic field. No single photon has been harmed in the process.
Your first scenario is handled by standard relativivity, how fast each object is moving is different from the frame of reference of object A, object B, and and the observer who they are moving at those speeds with respect to.
Quantum entanglement does not allow the transmission of infromation faster than the speed of light. The collapse of the wave function is transmitted instaneously but since what a particle decays into is random you can't use it transmit information.
No, there is no such thing as a perfectly rigid rod. The movement of the rod can't happen any faster than the speed of sound in the material that the rod is made. The speed of sound can't be faster than the speed of light since the interactions of the material making up the rod are electromagnetic in nature.
Although neutrinos were originality called neutrons for a few years before the name was changed due to confusion with what is called a neutron now, that quote comes from an article where Tesla is talking about penetrating rays, so he was talking about modern neutrons, not neutrinos. This was in an article about being able to harness immense power from cosmic rays, which now are measured with a flux of power less than a billion times smaller than solar power received, on average in northern Canada. Tesla was a very brilliant man and invented some amazing devices that actually worked, but the deifying of him by saying everything he said or made worked doesn't do any good.
c isn't just the speed of light. It's a constant that appears in all kinds of equations: sometimes as the speed of light, sometimes as the permeability of vacuum (Maxwell equations, etc.), sometimes as the ratio between matter and energy (E=mc^2), sometimes as the fundamental ratio between space-like and time-like quantities (relativity, etc.), and so on. It's quite amazing that this same constant comes out with the same value in all these different ways. (And, again, we can measure this constant in totally different experiments and come up with the same value.) This points to a fundamental symmetry in our universe, a realization which gave rise to relativity, quantum physics, and so on.
In short, you shouldn't think of it as merely being the speed that light (or any other particle) travels. It's a fundamental value that is deeply entrenched in just about every branch of physics you can think of. It so happens that it's also the speed that photons travel at. (That's, no accident, of course.) Changing the value of c even slightly would propagate through all of our physics equations, and would lead to totally different predictions for a host of results. (More specifically, we would start getting the wrong predictions for many things!)
So the explanation for this new result must be something rather more subtle than just adjusting c.
Gravity Biatches!
No, seriously though. Hear me out...
We know gravity can bend light going around a star, thus it has an effect on the speed of light much in the same manner as a refracting medium. When traveling near a source of gravity, c even in a vacuum isn't going to be constant.
The problem is, it's not that obvious at first. Gravity causes time dilation. So what does that affect? Oh yeah, that atomic clock you're using to time the speed of light. You're just not going to be able to measure the variation in c because of that.
This is much akin to taking a metal measuring stick along with a block made of the same metal and putting both in an oven, and then taking measurements. Then dipping both the block and measuring stick in liquid nitrogen, and again taking measurements. Oh yeah, the measurements didn't change did they? Now imagine if you swapped out the block of the same metal as the measuring stick for one with a different metal with a thermal expansion rate...
Apparently neutrinos may be affected by gravity in a different way than photons. At least if they're faster than light in certain situations, this may be the case. Alright physicists, have at it!
On the second one, the compression wave will propagate through the rod at less than C, assuming the rod is made from any existing material. That's how they calculate the theoretical maximum stiffness/weight ratio, by putting the compression wave speed equal to C.
Help I am stuck in a signature factory!
Another thought experiment. a 1" rod 1 light year long. you move it 1/16 of a centimeter. How long does it take for the movement to register at the other end? A: its instant, for it does not need to move any faster than the time it took you to move it.
This is clearly wrong. The input at one end of the rod propagates along the rod at a speed lower than c, if the rod had no mass and no inertia the input could propagate at c.
Another thought experiment. a 1" rod 1 light year long. you move it 1/16 of a centimeter. How long does it take for the movement to register at the other end?
A: its instant, for it does not need to move any faster than the time it took you to move it.
The atoms of the material would carry the signal at the speed of light to the other end. There would be a compression wave travelling along the rod. It would seem to you as if the whole rod moved, but in reality the effect wouldn't be instantly noticeable at the other end. The rod wouldn't have to be so long either, you could measure the same delay using a much shorter rod. Try tapping your mobile phone. The other end seems to move instantly, but in reality there is a delay.
If sound travelled at c in the rod there would be a delay of one year before it reached the other end. If you used the rod as an electromagnetic communication device there would be a delay. In the end the rod is an electromagnetic construction itself. It doesn't matter how rigid it is to you.
2. What if it was a single atom? If you "push" an atom, does the other side move immediately or is there a small delay? I'm guessing there's a small delay, or we'd be able to transmit data faster than the speed at light, albeit only at relatively small distances, such as the width of an atom.
...these results were calculated in ITALY.
I don't know about you, but according to my experience, NOTHING runs on time there.
Not even neutrinos.
So the idea that they arrived early? hahaha, clearly a clock error.
-Styopa
This experiment has not actually been conducted yet, but due to the faster-than-light nature of the experiment we are receiving the results here in the past.
This article would make a lot more sense if it read, "According to scientists at CERN, faster-than-light results have again been produced earlier today, after testing equipment was set up for an experiment scheduled for this Thursday, September 29th. The experiment will still be initiated as normal on Thursday, to avoid continuity problems, stated the scientists."
When I get my neutrino modem, I will use it to send my first post from the future.
But seriously - I can't imagine this being possible. If this is true - we'd be seeing distant supernovae on the neutrino detectors years before they flare up un the night sky. As far as I know the two events are measured within seconds of each other, even when they are millions of light years away. 0.03% of millions a years is much much more than seconds.
Run with the lemmings, and you'll get your feet wet.
if It arrives before it left - it's a bean counters wet dream they can check the results of the retest before they start and not bother doing the experiment if the result is disappointing saving all that cash.
I have to wonder....
Did they account for the rotation of the earth. The beam was fired from west to east. That would mean that the rotation of the earth would have to be added to the speed of light because the detector is not fixed, it is in motion toward the beam with the rotation of the earth. That speed would be something like 900 miles. I wonder if they took that into account......
See, this is where I've never understood relativity when it comes to C.
I don't know WHY it has to break causality. As light does have SOME mass, however infinitesimal, but it doesn't interact well with other things, it would just continue at its initial ejection speed until it interacts with something. As it doesn't interact well with well... anything, it would be very close to a constant speed.
Maybe the event energy required to produce these types of neutrinos is just enough higher than is required to produce light that it travels faster? Maybe the Neutrino is the universal constant and we've been looking at this all a little bit wrong.
All of this stuff is fairly interesting to me but I've never had time to investigate it fully and I want to get a course of some kind done in it so that its more to me than a bunch of scientists going "NO IT WILL FSCK WITH THE MATHS TOO MUCH!!!!".
Original contents of WHAT, punk?
Perhaps I'm trolling, perhaps I'm not.
Asimov already explained all of this in "Nemesis": gravity is a function of mass and speed. If you travel slower than light, gravity pulls you. If you travel faster than light, gravity repels you. Make sense to me!
Perhaps I'm trolling, perhaps I'm not.
If the measured distances is 20 meters too short, this would explain the error. I agree they should be able to measure the distance to 30 centimeters by high resolution GPS. But I suspect distance is the source of the error.
Polywater?
Those 4 hours are a cool number. I didn't know they had it.
Hogwash. The only reason FTL breaks causality is because relativity theory defines termporal ordering in terms of c. Using pure classical definitions, there will always be an observer for whom the causality principle holds (i.e. the FTL particle itself).
You'd be pushing its electromagnetic field with another electromagnetic field, and electromagnetic fields propagate at the speed of light.
Gravity Biatches! No, seriously though. Hear me out... We know gravity can bend light going around a star, thus it has an effect on the speed of light much in the same manner as a refracting medium. When traveling near a source of gravity, c even in a vacuum isn't going to be constant. The problem is, it's not that obvious at first. Gravity causes time dilation. So what does that affect? Oh yeah, that atomic clock you're using to time the speed of light. You're just not going to be able to measure the variation in c because of that. This is much akin to taking a metal measuring stick along with a block made of the same metal and putting both in an oven, and then taking measurements. Then dipping both the block and measuring stick in liquid nitrogen, and again taking measurements. Oh yeah, the measurements didn't change did they? Now imagine if you swapped out the block of the same metal as the measuring stick for one with a different metal with a thermal expansion rate... Apparently neutrinos may be affected by gravity in a different way than photons. At least if they're faster than light in certain situations, this may be the case. Alright physicists, have at it!
Darn it AC, if you're posting something mildly interesting, at least make a new account so it gets a default score of 1. So many people ignore 0 and -1.
In the end the rod is an electromagnetic construction itself. It doesn't matter how rigid it is to you.
An interesting side effect of a very long rod and the speed of sound vs the speed of gravity and light, is the effect it has in directionality of a simple type of gravitational antenna. To get a nice strong gravitational wave signal out of an "infinitely" long rod, not only do you need to point it perfectly, you have to curve it to match the wavefront of the expected gravitational wave, or else you just get a jumbled up mess at the transducer. Of course if you had multiple transducers and did lots of math...
"Science flies us to the moon. Religion flies us into buildings." - Victor Stenger
If you had an ideal incompressible solid, you might very well have created the first immovable object.
If in can't have a compression wave, it can't move.
When will these so-called "scientists" ever realize that nothing can move faster than the speed of light which includes these "ghost-particles"?
There is nothing to be gained by any of this ouija science.
... It's not yet clear how to make sense of this result.)
Of course we both know that it's 99.9% probably experimental error - they just havn't found it yet, and now they've asked the americans to help them find the error.
Run with the lemmings, and you'll get your feet wet.
You could make it of neutronium.
(just stand back a ways, if you did try to touch it, you would be sucked into the resulting black hole
Or, there could be flavors of neutrinos with different amounts of tachyonistic behavior.
In other words, if some neutrinos went at c, or very close to c (above or below), while others were tachyons, then the two results could be reconciled. If there
was a neutrino burst 4 years before 1987A, no one would have noticed it. So, maybe neutrinos have tachyonic hair.
By the way, if these results are true, your sig will need to be changed.
That's how much of an error in the presumed distance between the stations is required to explain a 60 ns discrepancy. Bearing in mind that neutrinos travel "as the crow flies" along a geodesic (effectively a straight line) between the two points, where light signals in the form of e.g. radio waves or in optical fibers, in addition to being retarded by an index of refraction, must follow an arc length along the Earth's surface if not worse.
rgb
Even when the experts all agree, they may well be mistaken. --- Bertrand Russell.
One might say, even at the speed of... ah, skip it.
I've always through Einsteins laws were bullshit, no offense to anyone who believes them. "Bending time" is ridiculous, and always has been.
Using some string left over from string theory?
On y va, qui mal y pense!
Two things: since the velocity of tachyonic neutrinos would depend on their energy it's plausible that the ones from a supernova were very high energy indeed, and thus traveled very close to the speed of light, albeit very very slightly faster rather than very very slightly slower.
The second thing is that it may well be that we don't understand the chronology of events within a supernova very well- what if the burst of neutrinos actually happened some time after the burst of light, but then outran it? After all, our current supernova models were designed to try to fit the data that appeared at the time to indicate that the neutrinos were emitted first...
Einstein's laws might be imperfect, but they are no more bullshit than Newtons laws are bullshit - Newtons laws are fine for speeds near zero, but very much imperfect for speeds near c.
And we already knew that Einstein's laws as you call them were imperfect before this, because quantum physics don't agree with Einstein's laws, see ERP experiment, also with the idea that here might be a smallest unit of time or space.
Science is the search for perfection within humanity, while God is the search for perfection elsewhere.
Hey don't blame me, IANAB
This thing is going to be tested again and again until they find a way to turn this into FTL travel.
Probably they will find that the neutrino doesn't travel faster than light, but instead the reference light bean somehow travels 20 nano seconds slower than expected.
Nothing to see here.
OR there is "dark matter" involved that slows down the light beam.
Privacy is terrorism.
Are neutrinos affected by gravity? If not, then I can see that they would not be affected by the curved space time of Earth and would appear to us (on Earth) to be going faster than light when both light and neutrinos are actually going at c. From the point of view of the neutrinos, a light beam (if there was a vacuum tunnel going through the Earth) would appear to curve towards the center. Both light and neutrino beam would be going at the same speed, but the light beam would have a longer distance to traverse (from the frame of the neutrino). In our reference frame, the neutrino beam appears to be going faster than c.
I'm not referring to the distance we measure, because our rulers are also curved. I'm asking if neutrinos are affected by the space time curvature created by Earth's gravity.
Based off this assumption being true, then this experiment repeated in space (away from the strong gravity inside the Earth) would not yield the same results. The beams would appear to be moving at the same speed.
I think to reconcile this with the supernova and the inconsistencies there is simply that the burst of light and neutrinos from different supernova are affected by different gravity fields on their way to Earth.
If it's already well known how gravity affects neutrinos, then please explain and don't flame.
What if neutrino propagation is unaffected by gravity? Time slows down in a gravitational well, as I recall, relative to being outside the well. In fact, GPS satellites have to compensate for this. What if this space time effect does not apply to neutrinos? Are the neutrinos seen to travel faster than c, or faster than light in our gravity well?
I haven't thought through if the question actually makes sense: it's a bit early on a Monday for my brain to deal with relativity, but I thought I'd raise the issue. Perhaps someone younger, more caffienated, or both, as a better idea.
Planck constant is in fact a momentum of photon. Having only this knowledge you can calculate it's mass.
Going further, you will found that photon is positively charged.
And that's why they are getting measurement errors on both LHC and OPERA.
By properly calculating elementary particles based on proper math and constants you can evaluate measurements.
All measurements are wrong, no wonder they got this one wrong as well.
Interesting, I wasn't aware that the energy of the SN1987A neutrinos had been measured. As an aside, I'm not at all sure that "rest mass" is the right phrase if they are indeed tachyons - perhaps "infinite speed mass?"
Let's roll with it, though, and assume they're really tachyons- how sure are we that we're observing the same kind of neutrinos? If the SN1987A tachyons had less than 10^-10 of the imaginary "rest mass" than the ones from CERN then they might travel closer to the speed of light even with much less total energy.
I've been experimenting with OPERA too - and it really is the fastest browser I have tried.
And that theory makes about as much sense as Superman being able to reverse time by reversing the Earth's rotation. (None.)
If a signal travels at light speed, it takes a certain amount of time to travel from point A to point B.
(If you're a light year away, it takes a year.)
If a signal travels at twice the speed of light, it *still* takes a certain amount of time to travel from point A to point B. .5 years.)
(If you're a light year away, it takes
Even a signal traveling at infinite speed will only manage to arrive at the destination at the same moment it was sent.
For a signal to arrive *before* it was sent, it would need to travel at *greater* than infinite speed.
If neutrinos are tachyonic, they have imaginary mass and would traverse gravity fields (such as the Earth's gravity in this experiment) faster than vacuum.
"Politicians and diapers must be changed often, and for the same reason."
If neutrinos are tachyonic and with imaginary mass, they could move faster through a gravitational field (the Earth's) in this experiment than in the vacuum of space between 1987A and us.
"Politicians and diapers must be changed often, and for the same reason."
Just a layman's idea but, could it be that due to some kind of gravitational interference, light is slowed down just a tad around Earth while some neutrino's are not thus allowing them to be measured as going faster than light?
Read what I mean, not what I wrote.
Wow that's quite a concept. To me that idea smacks of some unknown type of energy which has the potential of being converted into regular mass. However, it would seem to me complex mass would be impossible because as the particle's mass oscillated between the real and complex states its speed would likewise be respectively slower and then faster than c. Heh, imagine the shock waves from something breaking the light barrier a couple billion times per second, and the energy dumped into entropy. I don't think a particle with complex mass would make it very far. More like a one way ride...
Pure imaginary mass (the tachyon) is pretty neat to think about though. What kind of state could mass be in its "potential" form? The old E=mc^2 certainly implies that you can convert energy into mass, but I'm not aware of anybody who has created mass out of pure energy yet.
Clickety Click
732 km = 732000m .0024 comes out to 305,000,000m/s.
732000 /
That seems a bit clean of a number to be a coincidence.
Maybe the speed of light really is 305,000,000m/s and light has an undetectable mass by current measurement equipment, giving it a slower speed than a neutrino.
Think about it.
This is an honest question, not snark - I'm not nearly as scientifically grounded as many Slashdotters. Didn't quantum mechanics develop well before we had high-energies to play with? I've had the impression that we've known since the early 20th century that Newtonian physics wasn't complete, and that one of the amazing things about quantum physics is the ability of the early thought-experiments to get proven out by later real-world experiments and even incorporated into engineering principles (a la GPS). Is that accurate? And if true, what's the modern-day analogue to quantum physics here?
There's a nice summary here: http://theconversation.edu.au/neutrinos-and-the-speed-of-light-not-so-fast-3513 As usual, the media is reporting this as far more certain than the scientists think it is. As the article says "[the scientists] seem to be the only ones not jumping to conclusions just yet."
The 1987a SuperKAK measurements (at least) got the direction (approximately, +- 20 deg or so) and energy (again approximiately) of the incoming neutrinos; they came from the right direction (except for one, IIRC), and had "normal" energies, so the identification is pretty robust. The energies for this experiment were much higher. Now, for tachyons, that means that the 1987a guys should have been much faster, and arrived earlier. If the SuperKAK guys are smart (and they are) they should be looking through the old data right now for a FTL burst prior to 1987.
I am going out on a long limb here, but my physical intuition is tell me that supersymmetry may be involved. In simple supersymmetry, neutrino masses are zero, but there is some discussion out there where supersymmetric neutrinos are tachyonic.
I robustly predict a bunch of theoretical ... whimsy before this is resolved.
We've seen neutrinos from supernova arrive 4 hours earlier than light. But that from 170 light years distance.
If the difference was caused by neutrinos traveling faster than light, speed difference is roughly 1000 times smaller, than what was measured recently.
And if you say that well, neutrinos can travel at different speeds, it's hard to imagine a theory, where neutrinos produced by supernova produce slower neutrinos than those produced at CERN.
In other words: most likely it's some unaccounted detail in experiment.
I don't see people mentioning this glaring factor in this experiment: the neutrinos are traveling through SOLID MATTER, ie. Swiss and Italian earth, whereas c is the speed of light in VACUUM.
If the CERN measurements are correct, it might mean that there is some anomaly when neutrinos travel through the core of other particles (protons, neutrons etc). This explanation is consistent with SN1987A observation since the distance between SN1987A and Earth is mainly vacuum.
Bad physics alert: Possibly neutrino's top speed in vacuum is still 'c' but when traveling through matter it can somehow enter the core of a neutron or proton and exit simultaneously at the other end. If you sum up the lengths of all these core particles, it might give us the missing 18 meters.
Amoeba News - Multicellular organisms exist! Oh the horror...
First off, everyone, including the media needs to get the facts straight.. Relativity was not the brain-child of Einstein. In fact, it was one of the earliest "Facebook Scams" meaning... Einstein took the ideas of Henri Poincaré and reworked them... Henri Poincaré was the father of Relativity. Second. I hope the Theory of Relativity IS proven wrong. It is too constricting for us... Why limit our cognitive to theories that constrict the creativeness of the mind??
I am a firm believer that space is an entity and not a lack thereof. That is why most mass cannot break through
the light speed barrier. The neutron may be too small to collide with space and is not restricted by it. Remember there
is no speed without collision. This is why gravity compounds with increasing speeds. The only aspect of this theory
which is unknown to me is why space wan'ts to fill the *voids in it created by mass in a persistent way. Maybe mass creates
a vacuum in a space following with a timeline which cannot be studied. Analogically, It could be a vacuum in which
molasses is trying to fill. Doing this very slowly and without much force. But maybe I can crack the code. Why would
space be pushing back in a seemingly perpetual way?
Bonus: Traveling faster than light will put an object outside the fabric of the space/gravity boundaries. This effectively
causing a infinite speed increase with the remaining thrust used to achieve it. The result, whatever lies beyond our reality as
we know it.
Geez. Look up Tachyons. They are a theoretical massive particle traveling faster than the speed of light which is totally consistent with all theories of relativity. So basically everyone who talks as if it invalidates anything are just speaking talking points they read somewhere. You need to see the speed of light limit is valid for both sides. Relativity posits subluminal particles can never move faster than the speed of light in a vacuum, and superluminal particles can never move slower than the speed of light in a vacuum. Get yo shit straight!
I have talked about this with my friend who is a physicist at CERN. And the measurements in the experiment are not very "solid". They can only measure very indirectly when neutrinos being emitted. Their methodology can be microseconds off, they are using statistics to increase precision, and 60ns error is still very low. So chances that they have made a mistake when they measured neutrinos faster than light, are about 99.999%. The experiment should be redone, but not worth a BIG media announcement, which would most likely only make them look silly.