(Note: This is my first post in discussion, instead of just a comment. Feel free to suggest improvements.)
A few weeks ago in Less Wrong discussion, there was a discussion on whether or not we had found neutrinos traveling at superluminal velocities. That discussion can be found here:
Apparently, a paper was recently put into Arxiv from Ronald A.J. van Elburg, which has been popping up in the news as having indicated a possible explanation for the difference. To sum up the paper, instead of superluminal velocities, we may have a possible source of GPS error to compensate for.
Some of the news reports also correctly pointed out that this paper is currently as tentative as the first announcements about the Neutrinos were when OPERA made them.
The Michelson-Morley experiment shows that the experimental outcome of an interference experiment does not depend on the constant velocity of the setup with respect to an inertial frame of reference. From this, one can conclude the existence of an invariant speed of light. However, it does not follow from their experiment that a time-of-flight is reference frame independent. In fact, the theory of special relativity predicts that the distance between the production location of a particle and the detection location will be changed in all reference frames which have a velocity component parallel to the baseline separating source and detector in a photon time-of-flight experiment. For the OPERA experiment we find that the associated correction is approximately 32 ns. Judging from the information provided, the correction needs to be applied twice in the OPERA experiment. Therefore the total correctiotion to the final results is 64 ns. Thus bringing the apparent velocities of neutrino’s back to a value not significantly different from the speed of light. We end this short letter by suggesting an analysis of the experimental data which would illustrate the effects described.
Hypothesis to test if paper is correct:
We showed that in the OPERA experiment the baseline time-of-flight is incorrectly identified with the Lorentz transformation corrected time-of-flight as measured from a clock in a non4 stationary orbit and in fact exceeds it by at maximum 64 ns. The calculation presented contains some simplifying assumptions. A full treatment should take into account the varying angle between the GPS satellite’s velocity vector and the CERN-Gran Sasso baseline. We expect that such a full treatment will find a somewhat smaller value for the average correction. In addition such a full analysis should be able to predict the correlation between the GPS satellite position(s) and the observed time-of-flight.
Particles may not have broken light speed limit
(Note: This is my first post in discussion, instead of just a comment. Feel free to suggest improvements.)
A few weeks ago in Less Wrong discussion, there was a discussion on whether or not we had found neutrinos traveling at superluminal velocities. That discussion can be found here:
Apparently, a paper was recently put into Arxiv from Ronald A.J. van Elburg, which has been popping up in the news as having indicated a possible explanation for the difference. To sum up the paper, instead of superluminal velocities, we may have a possible source of GPS error to compensate for.
Some of the news reports also correctly pointed out that this paper is currently as tentative as the first announcements about the Neutrinos were when OPERA made them.
Arxiv link:
http://arxiv.org/PS_cache/arxiv/pdf/1110/1110.2685v2.pdf
Link to Preprint on Author’s page: (Thanks to Shminux)
http://home.kpn.nl/vanelburg30/Papers/RAJvanElburg_TimeOfFlight_Preprint.pdf
Summary:
The Michelson-Morley experiment shows that the experimental outcome of an interference
experiment does not depend on the constant velocity of the setup with respect to an inertial
frame of reference. From this, one can conclude the existence of an invariant speed of light.
However, it does not follow from their experiment that a time-of-flight is reference frame
independent. In fact, the theory of special relativity predicts that the distance between the
production location of a particle and the detection location will be changed in all reference
frames which have a velocity component parallel to the baseline separating source and detector
in a photon time-of-flight experiment. For the OPERA experiment we find that the
associated correction is approximately 32 ns. Judging from the information provided, the
correction needs to be applied twice in the OPERA experiment. Therefore the total correctiotion
to the final results is 64 ns. Thus bringing the apparent velocities of neutrino’s back
to a value not significantly different from the speed of light. We end this short letter by
suggesting an analysis of the experimental data which would illustrate the effects described.
Hypothesis to test if paper is correct:
We showed that in the OPERA experiment the baseline time-of-flight is incorrectly identified
with the Lorentz transformation corrected time-of-flight as measured from a clock in a non4
stationary orbit and in fact exceeds it by at maximum 64 ns. The calculation presented contains
some simplifying assumptions. A full treatment should take into account the varying angle between
the GPS satellite’s velocity vector and the CERN-Gran Sasso baseline. We expect that such a full
treatment will find a somewhat smaller value for the average correction. In addition such a full
analysis should be able to predict the correlation between the GPS satellite position(s) and the
observed time-of-flight.
References in the news:
http://www.pcmag.com/article2/0,2817,2394747,00.asp#fbid=iQWAnqFuW6P
http://www.ibtimes.com/articles/232354/20111017/neutrino-light-einstein-cern-opera-theory-of-relativity-debate-speed-of-light-particle-faster-than-l.htm
http://www.geekosystem.com/ftl-not-so-much/
As a side note, if this paper is correct, Eliezer may have won some money, since he made bets in a thread about this from the earlier discussion.
Edit: Fixed three broken links and header formatting.
Edit2: The original author retracted some of his comments on GPS. http://home.kpn.nl//vanelburg30//Publications.html has the link to why. Thanks to Shminux for finding this.