Is Lorentz symmetry violation possible for electrons and photons?

[wolram]

http://doc.cern.ch//archive/electronic/gr-qc/0402/0402009.pdf

A perspective on Quantum Gravity Phenomenology1
Giovanni Amelino-Camelia
aDipart. Fisica, Univ. Roma \La Sapienza” and INFN Sez. Roma1
P.le Moro 2, 00185 Roma, Italy
ABSTRACT
I give a brief overview of some Quantum-Gravity-Phenomenology research lines, focusing on studies of cosmic rays and gamma-ray bursts that concern the fate of Lorentz symmetry in quantum spacetime. I also stress that the most valuable phenomenological analyses should not mix too many conjectured new features of quantum spacetime, and from this perspective it appears that it should be dicult to obtain reliable guidance on the quantum-gravity
problem from the analysis of synchrotron radiation from the Crab nebula and from the analysis of phase coherence of light from extragalactic sources. Forthcoming observatories of ultra-high-energy neutrinos should provide several opportunities for clean tests of some simple hypothesis for the short-distance structure of spacetime. In particular, these neutrino studies, and some related cosmic-ray studies, should provide access to the regime E> mEp.
1 Quantum Gravity Phenomenology
Quantum-gravity research used to be completely detached from experiments. The horrifying smallness of the expected quantum-gravity eects, due to the overall suppression by powers
of the ratio of the Planck length (Lp ~ 10-35m) versus the characteristic wavelength of the particles involved in the process, had led to the conviction that experiments could never
possibly help. But recently there has been a sharp change in the attitude of a signi cant fraction of the quantum-gravity community. This is reflected also by the tone of recent
quantum-gravity reviews (see, e.g., Refs. [[1,2,3,4])]as compared to the tone of quantum gravity reviews published up to the mid 1990s (see, e.g., Ref. [[5, 6]]).
The fact that the smallness of an eect does not necessarily imply that it cannot be studied experimentally is not actually a new idea. There are several examples in physics, and even
remaining in the context of fundamental physics there is the noteworthy example of studies of the prediction of proton decay within certain granduni ed theories of particle physics.
The predicted proton-decay probability is really small, suppressed by the fourth power of the ratio between the mass of the proton and the granduni cation scale [mproton=Egut]4 ~ 10-64 ,
but in spite of this truly horrifying suppression, with a simple idea we have managed to acquire an excellent sensitivity to the new eect. The proton lifetime predicted by granduni ed theories is of order 1039s and \quite a few” generations of physicists should invest their
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i thought this might be interesting, some may have read it already
sorry about the quality of reproduction.

 

[marcus]

this is the best survey article in Quantum Gravity Phenomenology
(testing QG theories by observation) so far, as far as I know

here is an alternative link, to the one wolram gave

http://arxiv.org/gr-qc/0402009

Giovanni A-C chaired the first QG session of last July's
"Tenth Marcel Grossmann Meeting on General Relativity"
which was on QG testing
and he gave a summary talk which basically defines the field
and tells where it is and what the prospects are

to me this says that currently this paper that wolram linked us to is the definitive mainstream word on testing QG theories

so where does Jerzy Kowalski-Glikman fit in
a slightly belligerant looking young man in a motorcycle jacket (see his website)

http://www.ift.uni.wroc.pl/JK-G/

well he fits in at the footnote at the bottom of page 5
down below equation (3)

and in that footnote his work is somewhat overshadowed by
Amelino-Camelia's own work

be that as it may Jerzy K-G also gave a paper at that session of Tenth Marcel Grossmann and my private opinion of K-G is very high

 

[wolram]

the large boost high velocity regime, seems to be an
important aspect in testing QG, i am attempting to
understand this area of research, i am not sure if it
will provide an answer, given that there is so many
unknowns of the properties of Planck scale, but it may
be an interesting path to follow.

 

[wolram]

http://www.iop.org/EJ/abstract/-ff30=7/0264-9381/21/4/010

Abstract. We consider the implications for laser interferometry of the quantum-gravity-motivated modifications in the laws of particle propagation, which are presently being considered in attempts to explain puzzling observations of ultra-high-energy cosmic rays. We show that there are interferometric set-ups in which the Planck-scale effect on propagation leads to a characteristic signature. A naive estimate is encouraging with respect to the possibility of achieving Planck-scale sensitivity, but we also point out some severe technological challenges which would have to be overcome in order to achieve this sensitivity.
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as i am not a member i can not get the full article, anyone have an
alternative?

 

[wolram]

http://arxiv.org/abs/astro-ph/0309681

Constraints on possible Lorentz symmetry violation (LV) of order E/M_Planck for electrons and photons in the framework of effective field theory (EFT) are discussed. Using (i) the report of polarized MeV emission from GRB021206 and (ii) the absence of vacuum \v{C}erenkov radiation from synchrotron electrons in the Crab nebula, we improve previous bounds by 10^-10 and 10^-2 respectively. We also show that the LV parameters for positrons and electrons are different, discuss electron helicity decay, and investigate how prior constraints are modified by the relations between LV parameters implied by EFT.