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Time and the interpretation of canonical quantum gravity
Physical Review D, 1989The unsatisfactory status of the interpretation of the wave function of the Universe in canonical quantum gravity is reviewed. The ``naive interpretation'' obtained by straightforwardly applying the standard interpretive rules to the canonical quantization of general relativity is manifestly unacceptable; the ``WKB interpretation'' has only a limited ...
, Unruh, , Wald
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On the canonical approach to quantum gravity
Physical Review D, 1982General relativity has the property that, under the natural projection mapping, the image of the constraint surface in the phase space is a proper subset of the configuration space. This feature is not shared by other field theories of direct physical interest such as the Yang-Mills theory, nor by constrained systems which have been modeled after ...
Abhay Ashtekar, Gary T. Horowitz
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Canonical approach to quantum gravity
Classical and Quantum Gravity, 1987Summary: Dirac's canonical programme for the quantization of gravity is discussed. The order of operators in the `kinetic' part of the generator of normal deformations, \(\hat H_{\perp}\), is chosen to give the Laplace-Beltrami form. This follows from the requirement of invariance of the quantum theory under arbitrary contact transformations of the ...
Christodoulakis, Theodosios +1 more
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1992
Dirac’s theory of constrained Hamiltonian systems is first described, discussing in detail primary and secondary constraints, first-class and second-class constraints, Dirac brackets, effective Hamiltonian, total Hamiltonian and extended Hamiltonian. On quantization, the operator versions of first-class constraints become supplementary conditions on ...
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Dirac’s theory of constrained Hamiltonian systems is first described, discussing in detail primary and secondary constraints, first-class and second-class constraints, Dirac brackets, effective Hamiltonian, total Hamiltonian and extended Hamiltonian. On quantization, the operator versions of first-class constraints become supplementary conditions on ...
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Unimodular theory of canonical quantum gravity
Physical Review D, 1989Einstein's theory of gravity is reformulated so that the cosmological constant becomes an integration constant of the theory, rather than a "coupling" constant. However, in the Hamiltonian form of the theory, the Hamiltonian constraint is missing, while the usual momentum constraints are still present.
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A constraint on canonical quantum gravity?
Nature, 2003Gamma rays from the γ-ray burst (GRB) 021206 have been reported to be strongly linearly polarized1, with the estimated degree of polarization (80 ± 20%) being close to the absolute maximum of 100% — affording us the opportunity to constrain models of quantum gravity, which has had 1010 years to act on the photons as they travelled towards us.
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Time and complex numbers in canonical quantum gravity
Physical Review D, 1993It is noted that not only time but also the imaginary unit is absent from the Wheeler-DeWitt equation (WDE), the basic equation of canonical quantum gravity. This leads to a severe problem in an attempt to recover the time-dependent Schrodinger equation from the WDE. It is suggested that the problem will be solved if the WDE is actually complex and not
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Canonical quantization of gravity and quantum geometrodynamics
Soviet Physics Journal, 1986A representation in the form of the Faddeev-Popov path integral is constructed for solving the equations of quantum geometrodynamics (QGD). It is shown that QGD is equivalent to canonical quantization of gravity in a unitary gauge. Given the state of the gravitational field on the initial Cauchy hypersurface, a wave function of closed universe is ...
A. O. Barvinskii, V. N. Ponomarev
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Canonical Quantum Gravity on the Space of Vassiliev Invariants
International Journal of Theoretical Physics, 1999zbMATH Open Web Interface contents unavailable due to conflicting licenses.
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Epistemology of Loop Quantum Gravity in the Context of Canonical Quantum Gravity
Cunoașterea ȘtiințificăIn the quest to comprehend the fundamental nature of the universe, physicists have delved into the realms of quantum mechanics and general relativity. However, joining these two pillars of modern physics into a unified framework has been a longstanding challenge.
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