Evidence of a Correction To the Speed of Light 347
KentuckyFC writes: In the early hours of the morning on 24 February 1987, a neutrino detector deep beneath Mont Blanc in northern Italy picked up a sudden burst of neutrinos. Three hours later, neutrino detectors at two other locations picked up a second burst. These turned out to have been produced by the collapse of the core of a star in the Large Magellanic Cloud that orbits our galaxy. And sure enough, some 4.7 hours after this, astronomers noticed the tell-tale brightening of a blue supergiant in that region, as it became a supernova, now known as SN1987a. But why the delay of 7.7 hours from the first burst of neutrinos to the arrival of the photons? Astrophysicists soon realized that since neutrinos rarely interact with ordinary matter, they can escape from the star's core immediately. By contrast, photons have to diffuse through the star, a process that would have delayed them by about 3 hours. That accounts for some of the delay but what of the rest? Now one physicist has the answer: the speed of light through space requires a correction.
As a photon travels through space, there is a finite chance that it will form an electron-positron pair. This pair exists for only a brief period of time and then goes on to recombine creating another photon which continues along the same path. This is a well-known process called vacuum polarization. The new idea is that the gravitational potential of the Milky Way must influence the electron-positron pair because they have mass. This changes the energy of the virtual electron-positron pair, which in turn produces a small change in the energy and speed of the photon. And since the analogous effect on neutrinos is negligible, light will travel more slowly than them through a gravitational potential. According to the new calculations which combine quantum electrodynamics with general relativity, the change in speed accounts more or less exactly for the mysterious time difference.
So, what's the correction? (Score:2)
Re:So, what's the correction? (Score:5, Funny)
do they correct the idealized, or do they correct the observed?
Neither. You cannot correct the speed of light, because it isn't measured, it is DEFINED as EXACTLY 299,792,458 meters per second. So it is not the speed of light that needs to be updated, but the length of the meter.
Re:So, what's the correction? (Score:5, Insightful)
You have this the wrong way around. The speed of light is not defined, it is a universal constant. It is the length of the meter that is defined based on a combination of this constant, and the international standard of time. So you are correct that if light turned out to travel slower, the length of the meter would be slightly shorter, and the speed of light would still be exactly 299792458 meter per second. This would be according to the new length of the meter though, when expressed in the old length (which is what the poster is implicitly asking for), it would most certainly be less, and could be given as such.
Of course the truth is that the speed of light is perfectly fine as it is. It's just that light isn't always exactly 'light' when it travels through space.
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*This*.
It would've been better if they had focused on the transformation of light over time as it travels through space - that shit is interesting as all hell.
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Re:So, what's the correction? (Score:5, Informative)
None of this is the issue; speed of light stays constant, as does distance measurements. What changes is the understanding of the stability of a photon of light in a vacuum and the effect of this instability on travel time while passing near a gravitational well.
So while it's a photon of light, it travels light speed. When the energy converts to kinetic energy for a breather, it is affected by the gravitational pull, in a manner significantly stronger than a neutrino is affected. When it then flops back to being a photon, it is once again traveling at the speed of light.
What intrigues me about this is that this will also have implications regarding relativity, as every time the light flips state, it is essentially anchoring itself to a location in space from which the next photon flop can take its bearing. My mind can't quite grasp the further implications of this right now, but it could really mess with observation of light from a moving point (which all points are).
The recalibration is mostly on how we project distances based on light measurements; it's now become significantly trickier, as we need to account for gravity at specific moments.
Re:So, what's the correction? (Score:5, Interesting)
An easier example of this: light moves much slower than c in glass, or in water. The open question is: does light move non-trivially slower than c in the vacuum of space (which is not an idealized vacuum).
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SN 1987A is approximately 167,885 light years away, and they are showing a change of around 4 hours.
4 hours divided by 167,885 years (4029240 hours) = ~0.00001% (I hope I did that math correctly).
So like.. if the age of the Universe is 13.7 billion years, we would incorrectly believe it was 13.7000137 billion years old.
Re:So, what's the correction? (Score:4, Interesting)
In my conception (which may be flawed; I came to this conclusion after university physics classes that I didn't always understand as well as I should have, and these were 20+ years ago), the speed of light is governed by "the rate at which things can happen".
Electromagnetic waves propogate because a changing electric field produces a changing magnetic field which produces a changing electric field, etc. For reasons that I can't remember these changing fields occur in a slightly offset position each time, so that the fields move through space as they create each other.
If causes and effects could occur at an infinite rate, the waves would move infinitely fast; but since there always has to be a time gap between a cause and an effect, there is a fixed upper bounds for the rate at which these fields can produce each other.
There is also a fixed lower bounds on the minimum offset that can occur between the electric and magnetic fields.
So what you have is essentially effects occurring as quickly as possible over distances as small as possible. The ratio of the smallest possible time between a cause and an effect, and the smallest possible distance between an electric field and the magnetic field it produces and vice versa is ... the speed of light.
So why can't light go faster than c? Two reasons really: a) things "can't happen" faster than the cause-effect relationship of a magnetic field producing an electric field, and vice-versa; and b) distances between an electric field and the magnetic field it produces, and vice-versa, can't be smaller.
I vaguely remember that this is related to one of the cool aspects of Calculus - the ability to take the ratio of an infinitesimally small number to another infinitesimally small number, each expressed as a limit approaching zero, and get a calculatable, real number result.
In this case, if you take the limit as distance approaches zero, divided by time as it approaches zero, you get the speed of light - the ratio of two infinitesimally small numbers (the smallest unit of distance over the smallest unit of time).
Anyway that's how I explain it to myself.
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Agreed. But that's kind of my point. It's easy to wonder why light has to be bounded by a maximum speed because we can easily ask "why not faster"? For me it makes it clearer that there are fundamental aspects of physics/reality at work here to keep in mind that it's really the ratio of the smallest distance to the shortest time.
Yes, you do then have to ask "why is there a smallest distance" and "why is there a shortest time", but at least for these questions, I have an answer I can live with: because t
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Are you sure that the cause-effect relationship between an electric field propogating a magnetic field, and vice-versa, is included in this theory? Because there is no time component in the equations and therefore there is no unit of time to be made shorter.
There actually isn't any time between the change in the magnetic field and the change in the electric field; and there isn't any distance, either. But the ratio of these two values does produce a finite number, just like how calculus can calculate the
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None of your questions can be answered by science. Science is a great tool, but can't answer "why" things are the way they are. Just be grateful it is not different, otherwise we wouldn't even be here to ask the questions.
Similarly, asking what happened before the big bang is meaningless. Stephen Hawking puts it beautifully:
Since events before the Big Bang have no observational consequences, one may as well cut them out of the theory, and say that time began at the Big Bang. Events before the Big Bang, are simply not defined, because there's no way one could measure what happened at them.
This doesn't mean you can't enjoy pondering these questions if that's what you want to do, but do so with full realization you're now in the realm of philosophy, religion, and mysticism
Re:So, what's the correction? (Score:5, Informative)
It is the average speed of the light over very large distances that needs a correction, to account for the portions of travel where the light, well, is not light. The photons still move at 2.99x10^8m/s. It's the electrons and positrons that move slower.
Even that Sounds Wrong (Score:3)
The photons still move at 2.99x10^8m/s. It's the electrons and positrons that move slower.
This whole premise sounds wrong and needs data to confirm it. The problem is that the article is wrong to claim that neutrinos move at the speed of light - they have a non-zero mass and so must move slower than this. However their mass is incredibly small (probably ~100,000 times less than an electron - so small that we have not actually measured it yet!) so they move very close to the speed of light. What sounds dodgy is that they are claiming that the primary effect of the non-zero neutrino mass is negli
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OTOH, this is an interesting idea, and it may have greater imp
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I suspect the actual study, if not TFA, took that into consideration.
I actually find it more odd that the effects of mass on the neutrinos slowed them less than the effects of quantum gravity on the photons - The photons still lagged the neutrinos, rather than making up for a mere three hours' lag on a journey of 168,000 light-years? Truly mind-boggl
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You are mixing up rest mass (which neither the photon nor the neutrino has) with moving mass / impulse, which the photon has and the neutrino 'perhaps' has.
You claim that a neutrino has always mass (or more than a photon) is either plain wrong or grants you a noble prize if you can proof it.
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one part in 200,000,000 (Score:2)
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The way I read it, the speed of light (in a vacuum) isn't changed by this article.....just the expected speed of photons through a gravitational field of large enough mass and enough distance.
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Or it could be a badly written summary and article that completely misrepresent what is being stated.
If every science journalist on the planet were to spontaneously combust, not only would it introduce a whole new physical phenomenon, it would cause the average IQ of the planet to jump by at least 5 points.
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I'll at least give you points for not putting up a link to that Plasma Cosmology bullshit.
Don't mess with "c" (Score:5, Interesting)
There's an alternative explanation. Space-Time could have non-zero viscosity, and slow down photons.
There are a lot of reasons to consider that space might have a viscosity. For one thing, it would neatly explain the expansion of the universe, without the necessity of invoking dark matter and dark energy.
We live in interesting times!
-- Norm Reitzel
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Space has a sort of viscosity if it would mean gravity and expansion, but that doesn't have an effect on the speed but the frequency of a photon. So it's more like a spectral filter.
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You're playing games with words. Viscosity is "a measure of its resistance to gradual deformation by shear stress or tensile stress, due to friction between neighboring particles that are moving at different velocities". How could any part of that definition have anything to do with light?
Or do you intend viscosity to mean "a force which slows down photons"? In which case your sentence is "Space-Time could have a non-zero force which slows down photons, and slow down photons", in which case you aren't re
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It isn't a fixed length of time or distance (same thing at the speed of light in a vacuum, excepting spacial expansion). It's a statistical chance; each high energy photon has a chance at each and every point in time to split into an electron-positron pair (annihilation of the pair create gamma and higher photons, so it should only be those photons that split) and then those will travel for some time, being effected by gravity and all the other forces, before re-combining into a photon.
That's my complex way
In nearly 15 years, I've never done this... (Score:5, Funny)
FIRST POST
(however, the apparent local time when you see this post may differ based on the apparently non-constant nature of c )
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J.D. Franson's research appears to be Nobel prize worthy for its implications, and how much it could simplify our understanding of the universe. Wanting a first post on this is understandable.
Anyway, nothing 'virtual' at all about virtual particles. - Who would thought?
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Perhaps you forgot to take into consideration the speed of light through fiber is less than c?
Re:In nearly 15 years, I've never done this... (Score:5, Funny)
Perhaps you forgot to take into consideration the speed of light through fiber is less than c?
And the speed of light over Verizon fiber will vary based on whether it's sending Netflix photons or not.
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Mod up to 6!
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If this joke goes over someone's head who's sufficiently dense, does that affect it's arrival time?
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I'll let you know in a minute or two.
Ummm (Score:2)
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Photons need to have gamma-ray energies before they can create virtual electro-positron pairs. Visible light simply does not have enough energy to do this.
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2) We're talking about visible photons in this case, anyways.
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No, we aren't talking about visible photons. The emissions from the supernova were neutrinos and a gamma ray burst, the visible light travels still separately because of the other things in space that it interacts with that are transparent to gamma energy and above. But, yes, over the very large distances between us and the supernova it was not just a few photons that traveled at less than c for some time, but the chance rose high enough that it was nearly all of the photons.
All EM radiation travels at the
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That all makes sense, but it doesn't seem to match up to the observations.
The article says neutrons were observed arriving hours before optical photons, but what you are saying is that photons of high enough energy to become temporary particle pairs should arrive later than lower energy ones, which don't get slowed down by temporarily dropping below c.
If the chance to become a particle pair varies with energy, we ought to see the supernova change colour, starting off shining brightly in the visible spectrum
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Ah, this is getting off topic, but your comment raised a question in my mind. Suppose the light is blue shifted for an observer approaching it so that it does have the energy to form an electron-positron pair, but for another observer not approaching it as fast, it doesn't have the energy. Might one observer see the pair formation while the other did not?
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Bloody good question. They are called virtual particles, though. If forced to answer, I would suspect that the energy added by the observer traveling fast enough to blue shift the light that far, 50,000 times the wavelength (talking about a 500nm green down to 10picometer gamma) and 50,000x to 100,000x energy in keV, would require a good portion of c and would reduce the apparent distance covered to a lower amount that does not offer a high enough chance of a virtual particle interaction.
But that's just me
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Photons need to have gamma-ray energies before they can create virtual electro-positron pairs. Visible light simply does not have enough energy to do this.
No, they don't
They need those energies to create REAL, PERSISTENT electron-positron pairs, which fly away and last until they interact with something else - maybe centuries or eons later - that changes them to some other particle.
Virtual particle pairs, as long as their lifetime is less than a time that puts the product of the "error' in energy with the l
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That's what the article seems to suggest, yes. And that the virtual particle pair, if they exist for real time, would move at less than c for their short life-span. But the major change from Earth's perspective is that the gamma rays we saw did not travel in the straight line that the neutrinos did.
That might also explain the second neutrino burst (maybe, wild guess from a programmer). If some of the neutrinos went through a virtual particle state (Z boson, I think?) then they would also arrive at a differe
What the hell... (Score:5, Insightful)
Re:What the hell... (Score:5, Funny)
"more or less exactly" == "approximately", more or less exactly.
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It is almost precisely what you make it to be.
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It means their are error bars due to the limitation of the equipment and new equipment might change the answer at some decimal point down the line.
Example:
On my birthday I will be more or less 50. So if its before 4AM, in general parlance, people would say I"m 50 and they would more or less be exact. But if you accurately look at it I would actually be 50 until 4AM
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It means the reporter was lazy.
What gets corrected? (Score:3)
Presumably this happens all the time for light so what we've measured as the speed of light is correct, it's just that the true universal speed limit is higher and only neutrinos travel that fast. So we should find out that speed and use the speed of neutrinos when doing relativistic corrections.
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Presumably this happens all the time for light so what we've measured as the speed of light is correct, it's just that the true universal speed limit is higher and only neutrinos travel that fast. So we should find out that speed and use the speed of neutrinos when doing relativistic corrections.
But we are pretty sure neutrinos have mass now... so nope.
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Yup, it only affects a small percentage of photons for a very brief time. Schrodinger's equation and the rest of QED let you work out how many photons in a given burst over X amount of time. For most of our observations, in laser labs and other 'short' distances the effect shouldn't even be noticeable. But it might change astronomical measurements by a good bit. (well, 1.7 hours over 168,000 years, 1x10^-9; more or less, since light-years traveled and years traveled aren't identical at that distance due to
Finite chance? (Score:2)
For that matter, what is an infinite chance?
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Wait until you see these guys split up a bill for lunch.
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I'm not sure, but it may or may not involve monkeys, typewriters, and the works of Shakespeare.
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Given a specific period of time it WILL happen.
Given all time and space it might happen. Also: given a sub set of infinity it MAY happen within that subset but WILL happen in a larger subset of infinity.
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No it doesn't. Finite means finite.
Chance ranges from 0 to 1. All numbers between 0 and 1 (inclusive) are finite.
All chances are finite.
Is it possible? (Score:2)
Is there a 'less nerdy version'? (Score:3)
Genuine question - this seems like an interesting thing, but as someone whose expertise in physics is incredibly limited, is there anyone who would be willing to provide an "explain it like I'm five" version for an individual like myself who is interested in understanding the speed differences observed in the particles?
Thanks, internet!
Re:Is there a 'less nerdy version'? (Score:5, Informative)
photons and neutrinos both travel at approximately the same speed in vacuum - "the speed of light"
However, when it comes to going through a non-vacuum, like a star, neutrinos have a straight shot because they don't interact with anything and the photons have to run through a pinball game (or a pachinko game, if you've seen those) until they actually get out. Best estimates of the time difference to date are about 3 hours.
Because of that, they would expect to see the light about 3 hours after seeing the neutrino burst, but in this case it looks like it was 7+ hours instead.
This guy (if I'm understanding it right) is saying that even "in a vacuum" light does enough zig-zagging to add a few hours to the transit time of a 163000 lightyear trip.
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The guy is saying that we know photons can very quickly turns into an electron and it's friend a positron. They almost instantly turn back, but since the electron and it's friend are bigger and heavier than a photon of light they are affected by gravity more.
So, if the author is right, the light we saw took a different path to get to us. Just a little bit different, enough to add an hour over the course of 163,000 years.
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The first part you got right, the second I don't think so. From what I gather the photon is really like an "on and off again" couple, every so often they split apart to an electron and positron but almost instantly realize being on their own doesn't work so they get back together again. But in those brief moments they're single they're pulled much stronger towards parties, curving the path they take between our house and their house - not zigzagging.
Apparently over a 168000 light year stretch this adds up t
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In this explanation, why is there a net gravitational pull away from Earth? In those brief moments where the photons disassociate into electron/positron pairs, why are they pulled in any direction in particular? Why are they more likely to be pulled in a direction that slows them down rather than speeding them up?
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Why is the force of gravity pulling these electron/positron pairs away from Earth? Why is there any net effect at all? Is there "more stuff" on average on the other side of that supernova than on this side?
Correspondingly, if a supernova were to happen here and direct photons in the other direction, would the light get there "faster"? If not, why not? Why is the net drag caused by gravity always away from the direction that the light is travelling?
Sorry if this is a double-post, Slashdot eats my comment
'less nerdy version' for five-year-olds. (Score:2)
Photons travel slower than neutrinos because they dawdle.
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Genuine question - this seems like an interesting thing, but as someone whose expertise in physics is incredibly limited, is there anyone who would be willing to provide an "explain it like I'm five" version for an individual like myself who is interested in understanding the speed differences observed in the particles?
Thanks, internet!
Neutrinos go straight from start to destination, while photons have to take breaks every few minutes to pee, get a snack, fill up the tank, check out that yard sale, etc. They're like the cousin with ADD.
CAR ANALOGY, SUCKAS! (Score:3)
Okay, let's say you have two cars, a Porsche and an NSX (representing a photon and a neutrino, respectively). Both are limited by the same speed limit, which they always travel at (the speed of light).
Well, due to some weird quantum mechanics, every so often that Porsche splits into a pair of motorcycles, because apparently they got bought by Wayne Enterprises or something (in actuality, they split into an electron and anti-electron). They almost immediately join back together (forming a photon again), but
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In other words, the photon is like embarrassing photos of Kim Kardashian on TMZ, and a neutrino is like relevant news stories on Slashdot? :-P
Thanks for the help =)
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"explain it like I'm five"
Because I said so.
Done.
haha, no I've never said that to my kids. I always followed the why question as far as I could. And when I didn't know, the internet did.
subject (Score:2)
Based on the last 100 crackpots that said the speed of light was wrong... or that it was variable...
and that I've never heard of this guy, and no other physicists are talking about this that I can tell...
I'm calling bullshit.
Maybe I'll feel dumb tomorrow, but I'm pretty sure physics blogs would be exploring right now if this were even remotely true.
also, this is just a blog post...
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Maybe I'll feel dumb tomorrow, but I'm pretty sure physics blogs would be exploring right now if this were even remotely true.
also, this is just a blog post...
You've underestimated the speed of news on SlashDOT. It's much slower than the rest of the universe. Those events you mention should have already happened and you should feel stupid yesterday!
That's not what I took away from this... (Score:5, Interesting)
Franson's idea, as I understand it, is that during the small window between creation and annihilation, the massive particles are under the influence of gravity, which bleeds off energy. When the pair recombines, it results in a reduced velocity of the photon.
Now, as I understand it, reducing the energy of a photon would merely reduce its frequency (red-shifting), not affect its actual velocity.
However, over long distances, the total time required for a photon to travel distance X would thus be slightly more than X/c, based on the proportion of time spent as a pair of massive particles, rather than as a massless photon. From a statistical perspective, this yields an average velocity of slightly less than /c/ (the speed of light in a vaccuum).
This seems reasonable to me, at least at first.
mrsquid0 raises an issue, though: Photons in the visible light range are not sufficiently energetic to create an electron-positron pair. I do not know if the photons in question were in the visible light range or not.
NoNonAlphaCharsHere also raises an important point: the electron-positron pair *cannot* travel at the speed of light. In fact, he/she raises an even better idea than Franson; my reading of Franson's explanation is that gravity is slowing down the particles (gravity field behind the photon), but there's just as much opportunity for gravity to *speed up* the particles (gravity field in front of the photon).
Now, I don't feel like doing all the math for this one little message, so here are the things I would consider before taking this article (and the original paper) at face value:
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Photons in the visible light range are not sufficiently energetic to create an electron-positron pair. I do not know if the photons in question were in the visible light range or not.
The photons were in the visible, but the e+/e- pair exists "off the mass shell", which is an obscure way of saying that the normal conservation laws don't apply. There is an uncertainty relation that goes dE*dt >~ h/2Pi, which is to say: you can violate the law of conservation of energy by any amount so long as you do it for a short enough time. That's what's happening here.
That said, this whole thing is pure speculation, and somewhat problematic speculation at that. If you take the first neutrino detect
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Franson's idea, as I understand it, is that during the small window between creation and annihilation, the massive particles are under the influence of gravity, which bleeds off energy. When the pair recombines, it results in a reduced velocity of the photon.
I read it as just barely changing the vector of the light, not the velocity. All photons travel at c, but gravity could make the path of travel curve more than previously thought.
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If it's path curved, even infinitesimally, then it would miss us, wouldn't it? Unless you're saying that it curves one direction and then back again in a crazy squiggle pattern, somehow always re-aiming directly at us. Which doesn't sound remotely plausable.
"more or less exactly" (Score:2)
The headlines seems needlessly sensationalist (I know, shocking!) since apparently we're saying that photons don't always travel at the speed of light, not that the speed of light needs to be "corrected".
Bad summary/Theory Conflicts with data (Score:3)
The summary (and linked article) do a poor job of explaining the process and imply some change in the speed of light (there isn't one). The problem with the article (http://arxiv.org/abs/1111.6986) is that it ignores a bunch of more relevant data: Fermi-LAT observed photons from the same GRB over a very wide energy range placing an extremely good limit on effects like this proposed in the article (http://arxiv.org/abs/1305.3463).
Furthermore this is NOT new; the original article was posted in 2011 and only recently published in the "New Journal of Physics" which has apparently only published 16 volumes and I believe has had its email permanently redirected to my spam box.
Finally why do people link to Medium and not the actual article for physic related news items? We have demanded open, free access to all our papers since the birth of the internet (I speak as a physicist). Do everyone a favor and find the arxiv link and include it in your summary when submitting physics stories to Slashdot.
Lies, all lies (Score:2)
Apparently, there's a 1 in 10,000 chance that it's all a coincidence... and if you consider the number of observations being made, and the implications (aka other observations we should see), that's a really high chance. For example, it would mean that the Large Electron–Positron Collider was accelerating particles to faster than the speed of light in a vacuum, without anyone having noticed.
I am dubious (Score:4, Interesting)
When 1987A happened, it is fair to say that an enormous amount of attention was placed on those neutrinos - >> 1 paper per neutrino. The report of an earlier neutrino burst from the Mt Blanc LSD was discussed at length - see Arnett 1987 [harvard.edu] Table 1 for the time line.
The facts are these - the optical supernova could not be accurately timed, it wasn't bright at Feb 23.10 and it was at 2 / 23.443. The Mt Blanc LSD burst was at 2 / 23.12, while the other two detectors had a mutual burst at 2 / 23.316. Note that both neutrino bursts occurred before the optical SN was detected, and also that none of the other detected picked up the Mt Blanc LSD burst.
All of this has been known a long time, and numerous theories have been introduced to explain it.
- formation of a nlack hole [harvard.edu] (from the neutron star)
- formation of a quark star [harvard.edu] (from the neutron star)
- the Mt Blanc data were unrelated to the SN (that appears to be Arnett's viewpoint).
So, this is another explanation, and not a super compelling one to me. It will clearly never be proven from the SN 1987A data - the next such close supernova should have a lot of neutrino data, and maybe will resolve the issue.
anyone ever considered (Score:2)
...that the definition of the speed of light includes the term "in vacuo" for a reason?
It means, literally, "in vacuum". As in, the complete absence of matter along the path. Which is impossible even in laboratory conditions, never mind out in space where deep interstellar density runs on the order of tens of atoms per cubic metre. That might not sound like much but with the quantum probability of a photon polarising and forming a pair with mass, that pair will be subject to gravitational effects (even from
Better Red Shift Explanation? (Score:2)
Does the extreme distances of very far galaxies red shift and rapid expansion, better explained by vacuum polarization and a slow down of light over extreme distances? So that what we are not seeing is some sort of doppler shift, but instead of something akin to friction over very long distances using this process that both delays the light, and shifts the frequency to red? And if so, does this change the expansion of the universe answer?
Re:Which means (Score:5, Interesting)
The preceding relates to another thing, the quantum-mechanical mechanism for interfering with the actual speed of light. Those pairs of virtual particles that form also have mass. That means, while they temporarily exist, they also cannot be traveling at exactly light-speed; they have to be traveling slightly slower.
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I think you are confusing neutrinos, which have been known for a while, with tachyons, which are speculative and haven't been detected. Neutrinos don't move faster than light.
Re:Which means (Score:4, Funny)
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That is only true if the faster then light particle carries information. The way I heard it (and I don't remember where and whether it was much more then speculation) was that photons average the speed of light so they might go a bit faster, then a bit slower then c. There is also phenomena such as quantum entanglement that clearly show the speed of light being broken or bypassed with no information being transmitted faster then light. There are other quantum effects that also seem like they may be instant,
the force is weak with this one (Score:3)
and oh by the way photons can momentarily turn into other shit on their journeys yet somehow neutrinos can't.
I don't study particle physics, but from what I understand, for photons or neutrinos to "turn into other shit", they need to interact with something -- such as the particles they create, atomic nuclei, etc. Photons interact through electromagnetic forces -- which is the strongest force out there. In contrast, neutrinos interact via the weak force. As you might guess, that force is very weak. That's why neutrinos are so hard to detect.
Since photons interact with "other shit" via a much stronger force than ne
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What lack of observational evidence? Neutrinos do not produce Cerenkov radiation (light booms, caused by traveling faster than light) in a vacuum, but they do in a fluid such as they do at neutrino detectors such as this one. This indicates that they travel faster than light when light is barely slowed down, but not when light is in a vacuum. Hence, the evidence indicates that neutrinos travel close to, but not at the speed of light. How close? We haven't measured that yet (to my knowledge) but we can: dete
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If you chose your units of measure correctly, c^2 = c^3 = c^n = 1, and under this choice. E=m.
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they generally operate at 2.4GHz, which is the resonant frequency of water. Yes, a leaky microwave oven will interfere with wifi and bluetooth.
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What part of the site needs a tablet?
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So ALL THINGS are made by the devil except for infrared light and AM radio. Seems to explain why looking at things makes you question stuff (visible light is a lie!) and only AM radio tells the truth.