Results 101 to 110 of about 32,779 (246)
Some inflationary Einstein-Aether cosmologies [PDF]
Physical Review D, 2012 We show how to derive several families of accelerating universe solutions to an Einstein-Aether gravity theory. These solutions provide possible descriptions of inflationary behaviour in the early universe and late-time cosmological acceleration.
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de Sitter Excited State in Heterotic E8×E8${\rm E}_8 \times {\rm E}_8$ Theory
Fortschritte der Physik, Volume 73, Issue 12, December 2025.Abstract A novel duality sequence is devised to study late‐time cosmology in the heterotic E8×E8${\rm E}_8 \times {\rm E}_8$ setup of Horava and Witten with dynamical walls that are moving towards each other. Remarkably, the dimensionally reduced 4‐dimensional theory does not violate NEC and no bouncing or ekpyrotic phase is observed.
Suddhasattwa Brahma +5 more
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Expected value, to a point: Moral decision‐making under background uncertainty
Noûs, Volume 59, Issue 4, Page 1093-1125, December 2025.Abstract Expected value maximization gives plausible guidance for moral decision‐making under uncertainty in many situations. But it has unappetizing implications in ‘Pascalian’ situations involving tiny probabilities of extreme outcomes. This paper shows, first, that under realistic levels of ‘background uncertainty’ about sources of value independent
Christian Tarsney
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Bounding field excursions along null geodesics with applications to cosmology
Journal of High Energy PhysicsScalar fields in theories of gravity often inhabit a moduli space of vacua, and coherent spatial or temporal variations in their expectation values can produce measurable gravitational effects.
Aidan Herderschee, Aron C. Wall
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The Berry phase in inflationary cosmology
, 2013 We derive an analogue of the Berry phase associated with inflationary cosmological perturbations of quantum mechanical origin by obtaining the corresponding wavefunction.
+20 more
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Principle of «Observability»: Why Cannot the Theory of the Infinite Universe be Realized?
RUDN Journal of Philosophy, 2009 The present work demonstrates that all cosmological theories obey an epistemological relation: all steps cosmology makes in the direction of acquiring the status of a natural science are inversely proportional to its steps in the direction of allowing ...
A N Pavlenko
doaj
Universe, 2016 I show here that there are some interesting differences between the predictions of warm and cold inflation models focusing in particular upon the scalar spectral index n s and the tensor-to-scalar ratio r.
Øyvind Grøn
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Trans-Planckian footprints in inflationary cosmology
Physics Letters B, 2004 We consider a minimum uncertainty vacuum choice at a fixed energy scale Lambda as an effective description of trans-Planckian physics, and discuss its implications for the linear perturbations of a massless scalar field in power-law inflationary models.
ALBERGHI, GIAN LUIGI +2 more
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Non-commutativity in modified loop cosmology
European Physical Journal C: Particles and FieldsIn this study, we explore the pre-inflationary dynamics of the universe using a non-commutative extension of the mLQC-I framework. By incorporating a scalar field potential, we show that key features of Loop Quantum Cosmology (LQC), such as the quantum ...
Abolhassan Mohammadi
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The Structure and Interpretation of Cosmology: Part I - General Relativistic Cosmology
, 2004 The purpose of this work is to review, clarify, and critically analyse modern mathematical cosmology. The emphasis is upon mathematical objects and structures, rather than numerical computations. This paper concentrates on general relativistic cosmology.
Arp +24 more
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