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    One Way Light Velocity Toward Gran Sasso
    By Sascha Vongehr | September 23rd 2011 04:38 AM | 22 comments | Print | E-mail | Track Comments
    About Sascha

    Dr. Sascha Vongehr [风洒沙] studied phil/math/chem/phys in Germany, obtained a BSc in theoretical physics (electro-mag) & MSc (stringtheory)...

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    The people with the atom smashers, especially the ones at OPERA (Oscillation Project with E-tR Apparatus) in Italy’s Gran Sasso, announced to likely have a whopping 60 nano second systematic error with some neutrino experiments, but it makes for much better news to question Einstein. The scientists blame journalists for the hype, but of course they prepared everything just so that the press has no reason not to go ahead and make an Einstein spectacle out of it – the BBC promptly obliged. It is the usual ‘claim-to-be-fundamental-strategy’ as done with the God particle and all the other blown out of proportion humps-on-bumps. Note that Wired Science and SciAm for example go along with this worse than the BBC. Supposed to be the other way around? What does this tell us about science(media)?


    When the speed of light is involved, especially much nonsense comes shooting from all sides, not only from those with revolutionary claims, but often particularly from those who defend orthodoxy claiming that all this cannot possibly be because XYZ. Overwhelmingly, XYZ turns out to be nonsense.



    Plenty discuss those neutrino issues directly (I do so some more here), so I will merely give out a general warning. Most physicists are not experts on relativity, not even most of those who apply relativistic formulas daily in astronomy and particle physics. For illustration purposes, let me introduce the one-way speed of light problematic – this will give you at least one article about the speed of light today that will still be relevant after this neutrino storm is forgotten.


    If the speed of light is constant, is it the same in all directions?

    Einstein’s Theory of Special Relativity holds that there is no difference between physics as described by one reference system versus any other reference system that moves at a constant velocity relative to the first.


    So, now I will describe everything from a reference system that moves relative to you with half the speed of light c to the right. Einstein allowed me to do so. However, this also implies that ‘relative to you’, light moves three times faster to the right than to the left! Don’t believe it? Well, let us see:


    Remember, now we describe everything from a reference system that moves relative to you with half the speed of light c to the right. Thus, you move to the left at half the speed of light v = c/2. If you send out a short flash of light, it will travel outwards making up a spherical shell. After one second, that ball has a radius of one light second around the event of the flashing. However, since you moved half a light second to the left during this second, the light on your left is only another half light second towards your left. It did not get very far away from you because you followed it. On the other hand, the light to your right is already 1.5 light seconds away toward your right. Thus, relative to you (but as described in my favorite reference system), light moves three times faster to the right than to the left.*


    What is wrong with this? I guess maybe 30% up to perhaps 90% of physicists reading this have by now come to the conclusion that I am an idiot, but in fact nothing is wrong with what I wrote, nothing except for that the wording is carefully crafted to irk all those who claim to understand relativity but who actually only have a superficial understanding. But don’t we all know that light velocity is the same relative to everybody and everything? Yes, if “relative to them” is interpreted as “measured/described relative to their reference system in a certain way”. But I instead focused on the actual core of special relativity, namely that I can describe physics in any so called inertial system.


    General Relativity the Absolute

    Oh – but it gets much worse. In fact, the cosmic microwave background (CMB) is a rather special reference system left over from the big bang: the Theory of General Relativity insists on that such a unique (!) background exists in most cosmologies (even those without a big bang). Relativity theory thus not only allows us to use any reference system (Earth, space ship, …), but it moreover suggests that the CMB may be the one to pick, say in case you desire to make contact with an perhaps underlying physics from which relativity emerges.


    Earth is bound to the sun which in turn is bound to the Milky Way galaxy, which moves with about 600 km per second through the cosmic reference system, that is 0.2% of the speed of light. Therefore, relativity theory suggests that light may in fact fundamentally go almost always into some direction faster than into others, certainly in all of our earth bound experiments.


    Relativity isn’t about the velocity of light directly, it is about whether we can ever find out about it in case our most fundamental measurement is light itself. My thumb is always exactly one thumb long.


    The orthodox over-interpretation of relativity is all about that there is no preferred reference frame whatsoever. An ether with emergent Lorentz symmetry is another interpretation, entropic gravity yet another. Relativity theory is crucially about that the blasphemous interpretations are just as valid. Savor this for a moment:

    We do not just have some theory T that happens to have different interpretations, but the main point of that particular theory is that those descriptions are equally valid as far as T can tell!

    Such a theory gives you no indication as to which of its interpretations is more natural or closer to the truth.


    This property and the occurrence of such highly non-trivial dualities may be characteristic for fundamental theories. Quantum mechanics is certainly similar in this respect. Given the flood of blog articles on the speed of light these days, one aspect that can serve as a good indication for people who do not know what they are talking about is their defending a particular interpretation of relativity, regardless which one.

    ------------------------

    * UPDATE: After deleting some comments, let me point out that if you think you need to explain basic undergrad special relativity to me, it means that you did not understand what I wrote, period. Before commenting nonsense, first make sure you understand what an author actually wrote (no, it is not as simple as you may think); this and this reference may also help to give you an idea about the kind of issues this text is ultimately about. No, it is not about challenging Einstein - you got it wrong.

    Comments

    "I guess maybe 30% up to perhaps 90% of physicists reading this have by now come to the conclusion that I am an idiot,"

    What's unique about you, Sascha, is that you encourage that belief.

    vongehr
    Yes, I do not want to have any false friends. Those that do not fully understand relativity theory yet go out to defend it are not on our side, as their flawed arguments backfire and put the whole trustworthiness of science into question. We do not just need arguments, we as scientists need correct arguments!
    No one realy understands time, so a result that involves a discrepant time measurement is not a surprise - it really could be a new physics. As it involves a particle that barely notices what we see as the real world I dont think its any kind of gateway to FTL for anything with definite mass.Or even a threat to the Standard Model or Special Relativity. However this is the wonder of science, they are going to dig and dig and dig until it goes away as a mistake in the experimental method, or they figure out what it really means. Thats why science is fun, there is an answerr or there will be an answer one day if we keep working at it. Nothing else in the philisophical realm has this kind of satisfaction that once the password has been cracked and the tumblers fall into place we can know that what we know is valid - for the time being until all the complexity has been squeezed out of it. Science is pretty.

    Quentin Rowe
    Relativity isn’t about the velocity of light directly, it is about whether we can ever find out about it in case our most fundamental measurement is light itself. My thumb is always exactly one thumb long.
    I think Sascha has your comments mostly addressed by this paragraph.

    First off, I am nowhere near even an undergrad's level of relativistic physics. I'm mostly self-taught and curious.

    That being said, I find it hard to believe that people misinterpret what Sascha is writing. I understood it. Quentin hit it right on the head with the quoted selection.

    vongehr
    I find it hard to believe that people misinterpret
    I hope you did not take the UPDATE as an insult - it was put there after deleting a bunch of totally useless comments by people that you find hard to believe exist. This is the intertubes - selective perception and almost wistful misinterpretation is basically what it feeds on nowadays.
    I took no offense to the UPDATE. Actually, I'm glad I read this article after the comments had been cleaned up. I hate having to read through a bunch of useless comments to get to the more meaningful and relevant ones.

    Larry Arnold
    Well fortunately I don't have enough knowledge of relativity not to be called an idiot, so I can happily give the idiot's perspective.

    The dogma of science is that no amount of positive experimental results can ever prove a hypothesis, but it only takes one negative result to disprove it.

    No wonder the media are jumping about.

    I see it all as an attempt to measure the unmeasurable anyway for if this is a result of either miscalculation or inadequate time keeping it does not say a lot for the future of experimentation in this area does it? how many millions spent on scientific error? it's not the first time is it?
    vongehr
    no amount of positive experimental results can ever prove a hypothesis, but it only takes one negative result to disprove it.
    This statement has various versions but they all presume some concept of absolute truth, i.e. whether a theory for example is either wrong or correct. The discussion becomes much more civilized and nourishing if we simply map out a theory's domain of applicability. 
    Halliday
    Laurence:

    You stated:
    The dogma of science is that no amount of positive experimental results can ever prove a hypothesis, but it only takes one negative result to disprove it.
    This is a position asserted by Karl Popper.  Unfortunately, you are probably correct if you are asserting that all too many scientists ascribe to this position.

    For a more realistic view see Testing Scientific Ideas, at the Understanding Science website.

    David
    Well I've read your posts and your archive publications, and I still don't get your point. Why is this understanding of relativity in any way unique or deep? And how does it preempt experiments so you can dismiss the results just because it contradicts some dogmatic theoretical view of the world? If nature happened to decide for example to break the electroweak symmetry in such a way that a second gauge boson had zero mass, we would treat the Z-boson in the same way as light. The international system of units does define the meter in terms of the propagation speed of light in a QED vacuum, but this is just a human committee deciding that let's make this the basic unit of measure. Plenty of experiments are still trying to check whether Lorentz invariance is exact or not.

    Neutrinos were previously believed to be massless too so would behave like light (so people talked about "neutrino refraction" and so on), but experiments show they are probably massive. There are plenty of weird results about neutrinos in the last 20 years, but people dismissed them each time as an observational error. This time, the effect was too large to be immediately discarded as a mistake.

    Also get your facts straight, the neutrinos arrived 60 ns before they were allowed by special relativity, this is the measurement result. The combined statistical and systematic error in this experiment is 10 ns (claimed). Thus they have a 6-sigma discrepancy (claimed) from the results expected from special relativity. The measurement repeated over 3 years gave the same result. Probably this is still an experimental error because I don't personally believe that special relativity is violated, but they used to say the same thing about the apparent deviations between mercury's orbit and Newton's law of gravitation before Einstein's General Relativity explained it.

    vongehr
    Why is this understanding of relativity in any way unique or deep?
    Which understanding? I listed three types.
    And how does it preempt experiments so you can dismiss the results
    Who dismisses what results?

    About getting the facts straight - I was referencing the accuracies usual in the field. Why would I state the claimed accuracies of a pre-print that is published because the authors have big problems with the sys/stat errors and are asking for help???
    MikeCrow
    Neutrinos were previously believed to be massless too so would behave like light

    If someone could help me understand this.

    Assuming Neutrinos are massless, why would they be limited to the speed of the
    carrier of charge (ie photons), when they have no charge?
    Never is a long time.
    Halliday
    Mi Cro:

    First:  Photons are not the "carrier[s] of charge".  They are the mediators of the interaction between particles that carry electromagnetic charge.  Photons have "no charge", either.

    Second:  The relationship between the speed of massless particles and "the speed of light" has far more to do with the nature of space-time than to electromagnetism, light, and/or (electromagnetic) charge.

    In fact, here's a "shocker" for you:  No massless particles, including photons, actually "exists" (in one or more specific senses of "exists").  Massless "particles" can be viewed as merely direct interaction between massive particles via null geodesics (lines/paths) through space-time:  Direct interaction over zero space-time separation.

    I think that should give you enough to "chew on", for now.  ;)

    David
    MikeCrow
    David, You're absolutely right, I did butcher that.

    Second: The speed of light is due to the permeability of electric and magnetic fields through a vacuum in space-time (well that's what I was taught).

    Neutrino's having no charge, shouldn't have an electric or magnetic field, correct?

    Hence my question.
    Never is a long time.
    Halliday
    Mi Cro:

    You say:
    Second: The speed of light is due to the permeability of electric and magnetic fields through a vacuum in space-time (well that's what I was taught).
    Well, that is a correct explanation from a Newtonian/Galilean standpoint.  However, we have a century of data showing that that standpoint is only a low velocity, and low energy approximation.

    In point of fact, the way that Maxwell's electromagnetism violates Galilean relativity is one of the principle reasons it wasn't widely accepted until much later.  In a sense, Einstein came up with Special Relativity because he believed Maxwell more than he believed Newton.

    So, my second point remains:
    Second:  The relationship between the speed of massless particles and "the speed of light" has far more to do with the nature of space-time than to electromagnetism, light, and/or (electromagnetic) charge.
    (See also Sascha's response, bellow.)

    David
    vongehr
    You seem to be very much into the fact that light happens to be an EM phenomenon. Special RT has historically origins there, but the mechanical formulas (masses, energy, momentum, acceleration) go through entirely without EM, which is the reason for that Lorentz symmetry arises naturally in many condensed state systems like graphene. I do not see how you would like to accommodate a zero rest mass particle in orthodox special RT without it going at velocity c. How is it supposed to respond to acceleration?
    Anyway - the discussion is beside the point. I for one have never, not twenty years ago, believed for a single moment that neutrinos have no mass. I am not sure who ever actually believed the tentative standard model that far.
    Theory of relativity not only emphasizes on constantcy of light. It says that it is maximum velocity. Physically this means- when there is a relative velosity ,for both the velocities speed of light is constant.Implies that speed of light is changing for each reference(velocity) frame.In other words light is adjusting its velocity so as to mantain physics of theory of relativity and it is covering the distances with in certain time durations.(The time dilation is introduced to satisfy this situation) if time dilation is not introduced in theory of relativity definetly the velocity of light cannot be constant.Now the question is Time dilation is real? what is time? If we accept time dilation it gives lot of research regarding time and constancy of light? Theary of relativity started with the postulate that velocity of light is constant and maximum.Why light behaves like that? Answer is......... Further research

    vongehr
    It says that it is maximum velocity.
    Wrong! It holds that one cannot reach light velocity via smooth acceleration and that superluminal velocity must be bound to a particular reference frame in order to not violate causality. 
    UvaE
    I will merely give out a general warning. Most physicists are not experts on relativity, not even most of those who apply relativistic formulas daily in astronomy and particle physics.
    It's the price paid for specialization. Another example: ask physicists why we have tides or why an airplane flies, and you will get a pretty confusing tapestry of answers.
    Your idea is exactly what I was wondering what may have happened. But what about this:
    As I understood, in the US they had also found that neutrino's were going faster than lightspeed-constant, but within error-margin.

    As far as I know, the direction in US was almost opposite. Wouldn't those US-neutrino's had to be slower than lighspeed in that case?
    What is your explanation for that? Was that than due to the large errormargin? Or am I wrong about that direction? Or is the direction not exactly opposite? Or has the earth rotated relative to the "aether" :-} ... last one probably not ;-).

    Mm, I realise now that the time measurements will undo the 2 directional lightspeed difference. For the moment, this difference is not measurable. So it can't influence the experiments outcome.