TY - JOUR

T1 - Probing the Big Bang with quantum fields

AU - Ashtekar, Abhay

AU - De Lorenzo, Tommaso

AU - Schneider, Marc

N1 - Funding Information:
This work was supported by the NSF grants PHY-1505411 and PHY-1806356, the Eberly Chair funds of Penn State, and the Alexander von Humboldt Foundation.
Publisher Copyright:
© 2021. Advances in Theoretical and Mathematical Physics.All Rights Reserved.

PY - 2021

Y1 - 2021

N2 - By carrying out a systematic investigation of linear, test quantum fields ˆϕ(x) in cosmological space-times, we show that ˆϕ(x) remain well-defined across the big bang as operator valued distributions in a large class of Friedmann, Lemaˆıtre, Robertson, Walker space-times, including radiation and dust filled universes. In particular, the expectation values ⟨ˆϕ(x) ˆϕ(x′)⟩ are well-defined bidistributions in the extended space-time in spite of the big bang singularity. Interestingly, correlations between fields evaluated at spatially and temporally separated points exhibit an asymmetry that is reminiscent of the Belinskii, Khalatnikov, Lifshitz behavior. The renormalized products of fields ⟨ˆϕ2(x)⟩ren and ⟨ ˆ Tab(x)⟩ren also remain well-defined as distributions. Conformal coupling is not necessary for these considerations to hold.

AB - By carrying out a systematic investigation of linear, test quantum fields ˆϕ(x) in cosmological space-times, we show that ˆϕ(x) remain well-defined across the big bang as operator valued distributions in a large class of Friedmann, Lemaˆıtre, Robertson, Walker space-times, including radiation and dust filled universes. In particular, the expectation values ⟨ˆϕ(x) ˆϕ(x′)⟩ are well-defined bidistributions in the extended space-time in spite of the big bang singularity. Interestingly, correlations between fields evaluated at spatially and temporally separated points exhibit an asymmetry that is reminiscent of the Belinskii, Khalatnikov, Lifshitz behavior. The renormalized products of fields ⟨ˆϕ2(x)⟩ren and ⟨ ˆ Tab(x)⟩ren also remain well-defined as distributions. Conformal coupling is not necessary for these considerations to hold.

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U2 - 10.4310/ATMP.2021.V25.N7.A1

DO - 10.4310/ATMP.2021.V25.N7.A1

M3 - Article

AN - SCOPUS:85134532843

SN - 1095-0761

VL - 25

SP - 1651

EP - 1702

JO - Advances in Theoretical and Mathematical Physics

JF - Advances in Theoretical and Mathematical Physics

IS - 7

ER -