62:, it became clear that there is an unexpected connection between spacetime geometry (Killing horizons) and thermal effects for quantum fields. In particular, there is a very general relationship between thermal radiation and spacetimes that admit a one-parameter group of isometries possessing a bifurcate Killing horizon, which consists of a pair of intersecting null hypersurfaces that are orthogonal to the Killing field.
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The
Killing horizon also plays a role in the study of cosmic censorship hypotheses, which propose that singularities (points where quantities become infinite) are always hidden inside black holes, and thus cannot be observed from the rest of the Universe.
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In the context of black holes, a
Killing horizon is often associated with the event horizon. However, they are not always the same. For instance, in a rotating black hole (a Kerr black hole), the event horizon and the Killing horizon do not coincide.
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The concept of a
Killing horizon is significant in the study of Hawking radiation. This is a theoretical prediction that black holes should emit radiation due to quantum effects near the event horizon.
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The term "Killing horizon" originates from the
Killing vector field, a concept in differential geometry. A Killing vector field, in a given spacetime, is a vector field that preserves the metric.
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Penrose, Roger (1969). "Gravitational collapse: The role of general relativity".
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Chruściel, P. T. (2005). "Black-holes, an introduction". In
Ashtekar, A. (ed.).
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569:{\displaystyle r=r_{e}:=M+{\sqrt {M^{2}-Q^{2}-a^{2}\cos ^{2}\theta }}.}
473:. For this spacetime, the corresponding Killing horizon is located at
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Associated with a
Killing horizon is a geometrical quantity known as
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100 years of relativity; space-time structures: Einstein and beyond
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Furthermore, considering a particular linear combination of
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that, taken together, are the
Killing horizons generated by
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In the usual coordinates, outside the
Killing horizon, the
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contain
Killing horizons, which can coincide with their
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1117:Carroll, Sean M. (2004).
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1096:Wald, Robert M. (1984).
33:Einstein field equations
698:{\displaystyle \kappa }
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1009:black holes
471:ergospheres
355:Therefore,
1318:Categories
1214:relativity
1026:2015-07-15
993:References
867:See also:
955:Λ
937:π
900:Λ
847:ℏ
787:π
779:κ
773:ℏ
737:κ
693:κ
666:ϕ
663:∂
655:∂
632:∂
624:∂
598:∂
590:∂
559:θ
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533:−
520:−
411:−
331:−
294:−
208:∂
191:∂
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141:−
135:−
1176:Bibcode
1147:Bibcode
1054:Bibcode
52:Hawking
21:physics
1143:Nature
1125:
1104:
582:field
50:After
1269:This
1212:This
1020:(PDF)
1013:(PDF)
812:with
1275:stub
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1123:ISBN
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647:and
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