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Title: Inflation and the quantum measurement problem

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Journal Article: Publisher's Accepted Manuscript
Journal Name:
Physical Review D
Additional Journal Information:
Journal Volume: 94; Journal Issue: 4; Related Information: CHORUS Timestamp: 2017-06-24 16:48:49; Journal ID: ISSN 2470-0010
American Physical Society
Country of Publication:
United States

Citation Formats

Alexander, Stephon, Jyoti, Dhrubo, and Magueijo, João. Inflation and the quantum measurement problem. United States: N. p., 2016. Web. doi:10.1103/PhysRevD.94.043502.
Alexander, Stephon, Jyoti, Dhrubo, & Magueijo, João. Inflation and the quantum measurement problem. United States. doi:10.1103/PhysRevD.94.043502.
Alexander, Stephon, Jyoti, Dhrubo, and Magueijo, João. Wed . "Inflation and the quantum measurement problem". United States. doi:10.1103/PhysRevD.94.043502.
title = {Inflation and the quantum measurement problem},
author = {Alexander, Stephon and Jyoti, Dhrubo and Magueijo, João},
abstractNote = {},
doi = {10.1103/PhysRevD.94.043502},
journal = {Physical Review D},
number = 4,
volume = 94,
place = {United States},
year = {Wed Aug 03 00:00:00 EDT 2016},
month = {Wed Aug 03 00:00:00 EDT 2016}

Journal Article:
Free Publicly Available Full Text
Publisher's Version of Record at 10.1103/PhysRevD.94.043502

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Cited by: 4works
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  • We consider the measure problem in standard slow-roll inflationary models from the perspective of loop quantum cosmology (LQC). Following recent results by Ashtekar and Sloan, we study the probability of having enough e-foldings and focus on its dependence on the quantum gravity scale, including the transition of the theory to the limit where general relativity (GR) is recovered. Contrary to the standard expectation, the probability of having enough inflation, that is close to 1 in LQC, grows and tends to 1 as one approaches the GR limit. We study the origin of the tension between these results with those bymore » Gibbons and Turok, and offer an explanation that brings these apparent contradictory results into a coherent picture. As we show, the conflicting results stem from different choices of initial conditions for the computation of probability. The singularity-free scenario of loop quantum cosmology offers a natural choice of initial conditions, and suggests that enough inflation is generic.« less
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  • A generalized Bloch sphere, in which the states of a quantum entity of arbitrary dimension are geometrically represented, is investigated and further extended, to also incorporate the measurements. This extended representation constitutes a general solution to the measurement problem, inasmuch it allows to derive the Born rule as an average over hidden-variables, describing not the state of the quantum entity, but its interaction with the measuring system. According to this modelization, a quantum measurement is to be understood, in general, as a tripartite process, formed by an initial deterministic decoherence-like process, a subsequent indeterministic collapse-like process, and a final deterministicmore » purification-like process. We also show that quantum probabilities can be generally interpreted as the probabilities of a first-order non-classical theory, describing situations of maximal lack of knowledge regarding the process of actualization of potential interactions, during a measurement. - Highlights: • An extended Bloch representation of quantum measurements is given. • Quantum measurements are explained in terms of hidden-measurement interactions. • Quantum measurements are explained as tripartite processes. • The Born rule results from a universal average, over all possible measurement processes.« less