Results 31 to 40 of about 4,678 (262)
Monodromy inflation and an emergent mechanism for stabilising the cosmological constant
Journal of High Energy Physics, 2019 We show that a pair of field theory monodromies in which the shift symmetry is broken by small, well motivated deformations, naturally incorporates a mechanism for cancelling off radiative corrections to the cosmological constant.
Antonio Padilla
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Gravitational SL(2, ℝ) algebra on the light cone
Journal of High Energy Physics, 2021 In a region with a boundary, the gravitational phase space consists of radiative modes in the interior and edge modes at the boundary. Such edge modes are necessary to explain how the region couples to its environment.
Wolfgang Wieland
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From Classical Theory to Quantum Gravity [PDF]
Space Science Reviews, 2009 While it has been generally accepted for decades that general relativity and quantum theory are inconsistent, and that therefore general relativity must yield to a new theory of gravity compatible with quantum principles, the way to the new theory is still very unclear.
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From classical theory to spin 2 gravity
Intellectual Archive, 2021 We consider here the simple derivation of the Einstein equations by Fock. Then, we approach the way from the spin 1 fields to the spin 2 fields for massive and massless particles and we derive the gravity equations from this base. In conclusion, we discuss the principle of equivalence in classical Einstein theory and in the Schwinger spin 2 ...
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Classical Gauge Theory of Gravity
Theoretical and Mathematical Physics, 2002 The classical theory of gravity is formulated as a gauge theory on a frame bundle with spontaneous symmetry breaking caused by the existence of Dirac fermionic fields. The pseudo-Riemannian metric (tetrad field) is the corresponding Higgs field. We consider two variants of this theory.
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The cosmological constant as a boundary term
Journal of High Energy Physics, 2022 We compare the path integral for transition functions in unimodular gravity and in general relativity. In unimodular gravity the cosmological constant is a property of states that are specified at the boundaries whereas in general relativity the ...
Wilfried Buchmüller, Norbert Dragon
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An Ultralocal Classical and Quantum Gravity Theory
Journal of High Energy Physics, Gravitation and Cosmology, 2020 8 pages; an ultralocal gravity is quantized proving that full gravity can be affine quantized: a minor equation or two errors ...
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Mimetic massive gravity: beyond linear approximation
Journal of High Energy Physics, 2018 We present a theory of ghost-free massive gravity where the mass of the graviton is generated through the Brout-Englert-Higgs (BEH) mechanism and one of the four scalar fields used is that of mimetic gravity.
Ali H. Chamseddine, Viatcheslav Mukhanov
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Null infinity as an open Hamiltonian system
Journal of High Energy Physics, 2021 When a system emits gravitational radiation, the Bondi mass decreases. If the Bondi energy is Hamiltonian, it can thus only be a time-dependent Hamiltonian. In this paper, we show that the Bondi energy can be understood as a time-dependent Hamiltonian on
Wolfgang Wieland
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Large Quantum Gravity Effects: Unforeseen Limitations of the Classical Theory [PDF]
Physical Review Letters, 1996 3-dimensional gravity coupled to Maxwell (or Klein-Gordon) fields is exactly soluble under the assumption of axi-symmetry. The solution is used to probe several quantum gravity issues. In particular, it is shown that the quantum fluctuations in the geometry are large unless the number and frequency of photons satisfy the inequality $\N(\hbar Gω)^2 <&
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