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CATEGORIES:Theoretical Physics Seminars
SUMMARY:Generalised Functions and Singularities of Einstei
n’s equations - James Vickers (Southampton\, Maths
)
DTSTART:20170323T134500Z
DTEND:20170323T150000Z
UID:TALK2383AT
URL:/talk/index/2383
DESCRIPTION:This talk will describe how singularities of Einst
ein’s equations are treated within the theory of G
eneral Relativity. In other field theories\, such
as electromagnetism\, an important role is played
by point charges\, line sources and surface charge
s. Mathematically such concentrated sources are de
scribed using the classical theory of distribution
s. However Einstein’s equations are a system of n
on-linear PDEs so that one cannot use classical d
istribution theory. This talk will explain how a n
on-linear theory of generalised functions (Colombe
au algebras) may be used to describe important phy
sical solutions of Einstein’s equations such as Co
smic Strings\, shells of matter and impulsive grav
itational waves. It will also give a recent new de
scription of gravitational singularities in terms
of the evolution of test fields rather than the tr
aditional definition using world lines of test par
ticles. It will end by relating this work to new d
evelopments in the theory of PDEs.
LOCATION:Theory Library
CONTACT:Mike Gunn
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