2018/04/04 by Syed Moeez Hassan, Hassan, Syed Moeez
Physics and Astronomy · #Cosmology and Gravitation Theories #FOS: Physical sciences #General Relativity and Quantum Cosmology (gr-qc) #High Energy Physics - Theory (hep-th) #Noncommutative and Quantum Gravity Theories #Relativity and Gravitational Theory
paper · pdf · doi:10.48550/arxiv.1804.01389
openalex publication_date 2018/04/04 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
It was recently suggested that the cosmological constant problem as viewed in\na non-perturbative framework is intimately connected to the choice of time and\na physical Hamiltonian. We develop this idea further by calculating the\nnon-perturbative vacuum energy density as a function of the cosmological\nconstant with multiple choices of time. We also include a spatial curvature of\nthe universe and generalize this calculation beyond cosmology at a classical\nlevel. We show that vacuum energy density depends on the choice of time, and in\nalmost all time gauges, is a non-linear function of the cosmological constant.\nThis non-linear relation is a calculation for the vacuum energy density given\nsome arbitrary value of the cosmological constant. Hence, in this\nnon-perturbative framework, the cosmological constant problem does not arise.\nWe also discuss why the conventional cosmological constant problem is not\nwell-posed, and formulate and answer the question: "Does vacuum gravitate?"\nFinally, we give a derivation of reduction to quantum mechanics on a flat\nbackground from a non-perturbative gravity-matter theory.\n