The Hilbert space of quantum gravity is locally finite-dimensional
2017 ◽
Vol 26
(12)
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pp. 1743013
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Keyword(s):
We argue in a model-independent way that the Hilbert space of quantum gravity is locally finite-dimensional. In other words, the density operator describing the state corresponding to a small region of space, when such a notion makes sense, is defined on a finite-dimensional factor of a larger Hilbert space. Because quantum gravity potentially describes superpositions of different geometries, it is crucial that we associate Hilbert-space factors with spatial regions only on individual decohered branches of the universal wave function. We discuss some implications of this claim, including the fact that quantum-field theory cannot be a fundamental description of nature.
2019 ◽
Vol 28
(14)
◽
pp. 1944006
2020 ◽
Vol 29
(14)
◽
pp. 2043009
Keyword(s):
1982 ◽
Vol 34
(6)
◽
pp. 1245-1250
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Keyword(s):
1981 ◽
Vol 81
◽
pp. 177-223
◽
2020 ◽
Vol 35
(02n03)
◽
pp. 2040012
1966 ◽
Vol 7
(11)
◽
pp. 2107-2120
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2019 ◽
Vol 377
(2)
◽
pp. 971-997
2015 ◽
Vol 93
(4)
◽
pp. 456-459
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