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A Postquantum Theory of Classical Gravity?
Physical Review X, 2023 The effort to discover a quantum theory of gravity is motivated by the need to reconcile the incompatibility between quantum theory and general relativity. Here, we present an alternative approach by constructing a consistent theory of classical gravity coupled to quantum field theory.
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Hamilton–Jacobi Wave Theory in Manifestly-Covariant Classical and Quantum Gravity [PDF]
Symmetry, 2019 The axiomatic geometric structure which lays at the basis of Covariant Classical and Quantum Gravity Theory is investigated. This refers specifically to fundamental aspects of the manifestly-covariant Hamiltonian representation of General Relativity which has recently been developed in the framework of a synchronous deDonder–Weyl variational ...
Cremaschini, Claudio +1 more
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Brown-York charges at null boundaries
Journal of High Energy Physics, 2022 The Brown-York stress tensor provides a means for defining quasilocal gravitational charges in subregions bounded by a timelike hypersurface. We consider the generalization of this stress tensor to null hypersurfaces.
Venkatesa Chandrasekaran +3 more
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Unified Theory of Gravity and Electromagnetism: Classical and Quantum Aspects
SSRN Electronic Journal, 2021 A unified classical theory of gravity and electromagnetism with a torsion vector 0, proposed by S N Bose in 1952, is introduced. In this theory, the torsion vector acts as a magnetic current and it is shown that (i) the electromagnetism is invariant under continuous Heaviside–Larmor transformations and (ii) the electric and magnetic charges are ...
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On scalar and vector fields coupled to the energy-momentum tensor
Journal of High Energy Physics, 2018 We consider theories for scalar and vector fields coupled to the energy-momentum tensor. Since these fields also carry a non-trivial energy-momentum tensor, the coupling prescription generates self-interactions. In analogy with gravity theories, we build
Jose Beltrán Jiménez +2 more
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Quantum field theory with classical sources—linearized quantum gravity [PDF]
Classical and Quantum Gravity, 2018 Abstract In a previous work (Skagerstam 2018 arXiv: 1801.09947v1 [quant-ph] ) and in terms of an exact quantum-mechanical framework, -independent causal and retarded expectation values of the second-quantized electro-magnetic fields ...
Bo-Sture K Skagerstam +2 more
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Cuscuton gravity as a classically stable limiting curvature theory [PDF]
Journal of Cosmology and Astroparticle Physics, 2020 Finding effective theories of modified gravity that can resolve cosmological singularities and avoid other physical pathologies such as ghost and gradient instabilities has turned out to be a rather difficult task. The concept of limiting curvature, where one bounds a finite number of curvature-invariant functions thanks to constraint equations, is a ...
Quintin, Jerome, Yoshida, Daisuke
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Generating cosmological perturbations in non-singular Horndeski cosmologies
Journal of High Energy Physics, 2023 We construct a concrete model of Horndeski bounce with strong gravity in the past. Within this model we show that the correct spectra of cosmological perturbations may be generated at early contracting epoch, with mild fine-tuning ensuring that the ...
Yulia Ageeva +2 more
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Spacetime and the Philosophical Challenge of Quantum Gravity [PDF]
, 2001 We survey some philosophical aspects of the search for a quantum theory of gravity, emphasising how quantum gravity throws into doubt the treatment of spacetime common to the two `ingredient theories' (quantum theory and general relativity), as a 4 ...
Butterfield, Jeremy +3 more
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Grand unified theories in renormalisable, classically scale invariant gravity [PDF]
Journal of High Energy Physics, 2019 Abstract We analyze SO(N) and SU(N) gauge theories with scalars in adjoint and fundamental representations, coupled to renormalisable, classically scale invariant gravity. In the specific case of SO(11), we show that the quantum field theory can be can be asymptotically free in all couplings (hence ultra-violet complete).
Einhorn, Martin, Jones, D.R.
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