Results 41 to 50 of about 426 (131)
Restrictions on curved cosmologies in modified gravity from metric considerations
Physics Letters B, 2015 This study uses very simple symmetry and consistency considerations to put constraints on possible Friedmann equations for modified gravity models in curved spaces. As an example, it is applied to loop quantum cosmology.
Linda Linsefors, Aurelien Barrau
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Guiding and Manipulating Light Fields in Microstructured Liquid Crystals
Advanced Physics Research, Volume 5, Issue 7, July 2026.This review summarizes recent advances in guided‐wave optics enabled by microstructured liquid crystal (LC) devices, covering their fundamental material properties, key degree of freedom for dynamic light field manipulations. The advances of linear guided‐wave optics, nonlinear‐optics with spatial optical solitons, and microlasers in LC‐based devices ...
Shan‐shan Chang +2 more
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Starobinsky potential and power suppression in hybrid loop quantum cosmology
Physics Letters BWe study the effect on the primordial tensor power spectrum of varying the number of e-folds during slow-roll inflation in Loop Quantum Cosmology with a Starobinsky potential. Using the hybrid quantization approach, we derive the effective mass governing
Marceau Henry +2 more
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New Hamiltonian constraint operator for loop quantum gravity
Physics Letters B, 2015 A new symmetric Hamiltonian constraint operator is proposed for loop quantum gravity, which is well defined in the Hilbert space of diffeomorphism invariant states up to non-planar vertices with valence higher than three. It inherits the advantage of the
Jinsong Yang, Yongge Ma
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Magnetic properties of geraisites, the first tektite strewn field identified in Brazil
Meteoritics &Planetary Science, Volume 61, Issue 7, Page 1163-1178, July 2026.Abstract Geraisites are a newly recognized class of tektite from Brazil. They occur as centimeter‐sized, elongated to subspherical bodies scattered across surface gravel and shallow subsurface layers within a ~90‐km‐long strewn field extending between the municipalities of São João do Paraíso and Curral de Dentro, near the border between the states of ...
Melissa De Andrade Nunes +7 more
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Topological Point Defects in SmC* Liquid Crystals Under Mechanical Disturbance
Advanced Materials Interfaces, Volume 13, Issue 11, 9 June 2026.Tangetial air jet shear inducess island formation and nucleates topological point defects in uniform SmC films. Island bounded by edge dislocation loops shrink and transform into isolated point defects under continued shear. Mechanical perturbatio provides a controllable route for defect engineering in smectric liquid crystal thin films.
Gunganist Kongklad +3 more
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Loop quantum cosmology with a non-commutative quantum deformed photon gas
European Physical Journal C: Particles and Fields, 2018 The non-commutativity of the space-time had important implications for the very early Universe, when its size was of the order of the Planck length. An important implication of this effect is the deformation of the standard dispersion relation of special
Yunxin Ye, Tiberiu Harko, Shi-Dong Liang
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Background Instability of Quintessence Model in Light of Entropy and Distance Conjecture
Fortschritte der Physik, Volume 74, Issue 6, June 2026.ABSTRACT We apply the covariant entropy bound argument supporting the de Sitter swampland conjecture to the quintessence model, to find out the condition for the background to be unstable. More concretely, the background is unstable when the matter entropy given by the species number of the effective field theory increases more rapidly than the ...
Min‐Seok Seo
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Numerical Techniques in Loop Quantum Cosmology
Symmetry, Integrability and Geometry: Methods and Applications, 2012 In this article, we review the use of numerical techniques to obtain solutions for the quantum Hamiltonian constraint in loop quantum cosmology (LQC).
David Brizuela +2 more
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Mathematical Structure of Loop Quantum Cosmology: Homogeneous Models
Symmetry, Integrability and Geometry: Methods and Applications, 2013 The mathematical structure of homogeneous loop quantum cosmology is analyzed, starting with and taking into account the general classification of homogeneous connections not restricted to be Abelian.
Martin Bojowald
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