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European Physical Journal C: Particles and Fields, 2019 Mimetic gravity can be described as a formulation capable of mimicking different evolutionary scenarios regarding the universe dynamics. Notwithstanding its initial aim of producing a similar evolution to the one expected from the dark components of the ...
Eunice Bezerra, Oswaldo D. Miranda
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Quantum Reduced Loop Gravity and the foundation of Loop Quantum Cosmology [PDF]
, 2016 Quantum Reduced Loop Gravity is a promising framework for linking Loop Quantum Gravity and the effective semiclassical dynamics of Loop Quantum Cosmology. We review its basic achievements and its main perspectives, outlining how it provides a quantum description of the Universe in terms of a cuboidal graph which constitutes the proper framework for ...
arxiv +1 more source
Symmetry Reduction of Loop Quantum Gravity [PDF]
Class.Quant.Grav. 28 (2011) 245014, 2010 The relation between standard Loop Quantum Cosmology and full Loop Quantum Gravity fails already at the first nontrivial step: The configuration space of Loop Quantum Cosmology can not be embedded into the configuration space of full Loop Quantum Gravity due to a topological obstruction.
arxiv +1 more source
On solutions of loop quantum cosmology [PDF]
The European Physical Journal C, 2013 Loop quantum cosmology is considered in inflation era. A slow roll scalar field solution with power law potential is presented in the neighborhood of transition time, i.e. when the universe enters inflation phase from super-inflation. The compatibility of the model with Planck 2013 data is discussed. The domain of validity of second and the generalized
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Qualitative study in loop quantum cosmology [PDF]
Classical and Quantum Gravity, 2017 This work contains a detailed qualitative analysis, in General Relativity and in Loop Quantum Cosmology, of the dynamics in the associated phase space of a scalar field minimally coupled with gravity, whose potential mimics the dynamics of a perfect fluid with a linear Equation of State (EoS).
Aresté Saló, Llibert +2 more
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Is a loopy and noncommutative early Universe viable?
Physics Letters B, 2023 We conduct a (pre-)inflationary dynamics study of the chaotic quadratic potential within the framework of a simple noncommutative extension of effective loop quantum cosmology put forward recently.
Luis Rey Díaz-Barrón +3 more
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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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Some conceptual issues in loop quantum cosmology [PDF]
, 2016 Loop quantum gravity is a mature theory. To proceed to explicit calculations in cosmology, it is necessary to make assumptions and simplifications based on the symmetries of the cosmological setting. Symmetry reduction is especially critical when dealing with cosmological perturbations.
arxiv +1 more source
Loop cosmological dynamics and dualities with Randall-Sundrum braneworlds [PDF]
, 2006 The discrete quantum geometric effects play an important role in dynamical evolution in the loop quantum cosmology. These effects which are significant at the high energies lead to the quadratic energy density modifications to the Friedmann equation, as ...
A. Ashtekar +6 more
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Loop quantum cosmology and inhomogeneities [PDF]
General Relativity and Gravitation, 2006 Inhomogeneities are introduced in loop quantum cosmology using regular lattice states, with a kinematical arena similar to that in homogeneous models considered earlier. The framework is intended to encapsulate crucial features of background independent quantizations in a setting accessible to explicit calculations of perturbations on a cosmological ...
openaire +3 more sources