On the differential topology of space-time
1971 ◽
Vol 69
(2)
◽
pp. 295-296
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Keyword(s):
It has often been assumed in cosmology theory(1) that there exists an average density of matter in space which is everywhere greater than zero. Under this assumption the space-time M will be foliated by curves each of which represents the life history of a particle. In keeping with the postulates of general relativity theory we shall refer to these curves as geodesics. Letting X denote the space of particles one obtains a projection f: M → X which assigns to every P ∈ M the particle found at P. Conversely, given the projection f:M → X, one can recover the geodesics: they are precisely the fibres f−1(x), x∈X.
1921 ◽
Vol 27
(4)
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pp. 182-187
2018 ◽
2021 ◽
1988 ◽
Vol 68
(1)
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pp. 46-46
Keyword(s):
2006 ◽
Keyword(s):