Results 21 to 30 of about 6,202 (230)
L'emergenza dello spazio-tempo nella gravità quantistica e nella cosmologia quantistica
Philosophy Kitchen, 2019 Our best description of spacetime is provided by general relativity – yet, this theory is not thought to be fundamental. Instead, it is expected to be replaced by a theory of quantum gravity, which may not feature spacetime fundamentally.
Karen Crowther
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The Quantum Cosmological Constant [PDF]
Symmetry, 2019 We present an extension of general relativity in which the cosmological constant becomes dynamical and turns out to be conjugate to the Chern–Simons invariant of the Ashtekar connection on a spatial slicing. The latter has been proposed Soo and Smolin as a time variable for quantum gravity: the Chern–Simons time.
Alexander, S, Magueijo, J, Smolin, L
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Loop Quantum Cosmology, Modified Gravity and Extra Dimensions
Universe, 2016 Loop quantum cosmology (LQC) is a framework of quantum cosmology based on the quantization of symmetry reduced models following the quantization techniques of loop quantum gravity (LQG).
Xiangdong Zhang
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Cosmological quantum billiards [PDF]
, 2012 The mini-superspace quantization of D=11 supergravity is equivalent to the quantization of a E10/K(E10) coset space sigma model, when the latter is restricted to the E10 Cartan subalgebra. As a consequence, the wavefunctions solving the relevant mini-superspace Wheeler-DeWitt equation involve automorphic (Maass wave) forms under the modular group W ...
Kleinschmidt, Axel, Nicolai, Hermann
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Tachyon field in loop cosmology
Physics Letters B, 2020 The evolutionary pictures of tachyon field in modified loop cosmology have been investigated. We present the dynamical behavior of the tachyon field associated with an exponential potential and find that the pre-inflation dynamics are very similar in ...
Kui Xiao
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Pytanie o jedność nauki na przykładzie kosmologii antropicznej
Studia Philosophiae Christianae, 2023 Given the ongoing process of the differentiation of sciences, it is worth posing a question about the possibility of them being integrated. This matter will be explored with reference to anthropic cosmology.
Sławomir Leciejewski
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Noncommutative Quantum Cosmology [PDF]
Physical Review Letters, 2002 We propose a model for noncommutative quantum cosmology by means of a deformation of minisuperspace. For the Kantowski-Sachs metric we are able to find the exact wave function. We construct wave packets and show that new quantum states that ``compete'' to be the most probable state appear, in clear contrast with the commutative case.
Octavio Obregón +2 more
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Quantum Gravity Effects in Cosmology
EPJ Web of Conferences, 2018 Within the geometrodynamic approach to quantum cosmology, we studied the quantum gravity effects in cosmology. The Gibbons-Hawking temperature is corrected by quantum gravity due to spacetime fluctuations and the power spectrum as well as any probe field
Gu Je-An, Pyo Kim Sang, Shen Che-Min
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Effective Field Theory of Loop Quantum Cosmology
Universe, 2019 Quantum cosmology is traditionally formulated in a minisuperspace setting, implicitly averaging fields over space to obtain homogeneous models. For universal reasons related to the uncertainty principle, quantum corrections then depend on the size of the
Martin Bojowald
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On the holographic basis of loop quantum cosmology
European Physical Journal C: Particles and Fields, 2018 In this work, we obtain the loop quantum cosmology dynamical equations, plus a positive cosmological constant, from the Bekenstein–Hawking entropy-area relation given by Loop Quantum Black Holes, by the use of the Jacobson formalism (Phys Rev Lett 75 ...
C. A. S. Silva
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