Abstract spacetimes and their Lorentz groups
J. Math. Phys. 37, 3073 (1996); doi:10.1063/1.531555
Issue Date: June 1996
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It has recently been discovered [A. A. Ungar, Am. J. Phys. 59, 824 (1991); 60, 815 (1992)] that the set R
={v
R3 :
v
<c} of all relativistically admissible velocities in Euclidean three-space R3, with a binary operation
given by relativistic velocity addition, forms a gyrogroup (R
,
). The gyrogroup (R
,
) reduces to the group (R3,+) in the limit c
, + being the prerelativistic velocity addition (that is, the ordinary vector addition in the Euclidean three-space R3). The binary operation
in R
is gyroassociative and gyrocommutative, as opposed to the binary operation + in R3 which is associative and commutative. In this article we extend the study of gyrogroups into that of Lorentz groups. In particular, we find that a gyrogroup must be equipped with a cocycle form in order to be extendible into a Lorentz group. We thus study gyrogroups that are equipped with a cocycle form, and their resulting Lorentz groups. Interestingly, the cocycle form needed for the extension of gyrogroups into Lorentz groups involves a cocycle identity which is known to be useful in various branches of mathematics [B. R. Ebanks and C. T. Ng, Aequat. Math. 46, 76 (1993)]. ©1996 American Institute of Physics.
R3 :
v
<c} of all relativistically admissible velocities in Euclidean three-space R3, with a binary operation
given by relativistic velocity addition, forms a gyrogroup (R
). The gyrogroup (R
) reduces to the group (R3,+) in the limit c
, + being the prerelativistic velocity addition (that is, the ordinary vector addition in the Euclidean three-space R3). The binary operation
in R| History: | Received 26 September 1994; accepted 20 February 1996 |
| Permalink: |
http://link.aip.org/link/?JMAPAQ/37/3073/1 |
KEYWORDS and PACS
PUBLICATION DATA
0022-2488 (print)
1089-7658 (online)
REFERENCES (18)
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