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Liegener, Klaus; Rudnicki, Łukasz

Algorithmic approach to cosmological coherent state expectation values in loop quantum gravity. (English) Zbl 1479.83092

Classical Quantum Gravity 38, No. 20, Article ID 205001, 39 p. (2021).
Summary: Within the lattice approach to loop quantum gravity on a fixed graph, explicit calculations tend to be involved and are rarely analytically manageable. However, being focused on a particularly interesting setting, concerned with expectation values with respect to coherent states on the lattice (sharply peaked on isotropic and flat cosmology), we are able to provide several simplifications which can facilitate approaching beyond-state-of-the-art problems. We present a step-by-step algorithm resulting in an analytical expression including up-to-first-order corrections in the spread of the coherent state. The algorithm is developed in such a way that it makes the computation straightforward and easily implementable.

Cited in 3 Documents

MSC:

83C45 Quantization of the gravitational field
81Q20 Semiclassical techniques, including WKB and Maslov methods applied to problems in quantum theory
81R30 Coherent states
83C27 Lattice gravity, Regge calculus and other discrete methods in general relativity and gravitational theory

Keywords:

quantum; gravity; loop quantum gravity; semiclassicality; lattice; coherent states
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References:

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