文档介绍：GRA VITY
GA UGE THEORIES AND GEOMETRIC
ALGEBRA
An thon y Lasen b y
Chris Doran and
Stephen Gull
MRA O
Cavendish L ab or atory
Madingley R o ad
Cambridge CB
HE
UK
Abstract
A new gauge theory of gra vit y is presen ted
The theory is constructed in a
at bac kground spacetime and emplo ys gauge
elds to ensure that all relations
bet w een ph ysical quan tities are indep enden t of the p osition and orien tation of
the matter
elds
In this manner all prop erties of the bac kground spacetime
are remo v ed from ph ysics
and what remains are a set of
in trinsic
relations
bet w een ph ysical
elds
F or a wide range of phenomena
including all presen t
exp erimen tal tests
the theory repro duces the predictions of general relativit y
Di
erences do emerge
ho w ev er
through the
rst
order nature of the equations
and the global prop erties of the gauge
elds
and through the relationship with
quan tum theory
The prop erties of the gra vitational gauge
elds are deriv ed
from b oth classical and quan tum viewp oin ts
Field equations are then deriv ed
from an action principle
and consistency with the minimal coupling pro cedure
selects an action whic h is unique up to the p ossible inclusion of a cosmological
constan t
This in turn singles out a unique form of spin
torsion in teraction
A
new metho d for solving the
eld equations is outlined and applied to the case
of a time
dep enden t
spherically
symmetric p erfect
uid
A gauge is found
whic h reduces the ph ysics to a set of essen tially Newtonian equations
These
equations are then applied to the study of cosmology
and to the formation and
prop erties of blac k holes
Insistence on
nding global solutions
together with
the
rst
order nature of the equations
leads to a new understanding of the
role pla y ed b y time rev ersal
This alters the ph ysical picture of the prop erties
of a horizon around a blac k hole
The existence of global so