Results 51 to 60 of about 59,420 (206)
SCALAR COSMOLOGICAL PERTURBATIONS OF PRESSURELESS MATTER IN THE BRANEWORLD MODEL
Odessa Astronomical Publications, 2012 We present a complete set of differential equations describing the evolution of scalar cosmological perturbations of pressureless matter on the brane in the general case where the action of the model contains the induced-curvature term as well as the ...
A. V. Viznyuk, Yu. V. Shtanov
doaj +1 more source
Evolution of perturbations in distinct classes of canonical scalar field models of dark energy
, 2010 Dark energy must cluster in order to be consistent with the equivalence principle. The background evolution can be effectively modelled by either a scalar field or by a barotropic fluid.The fluid model can be used to emulate perturbations in a scalar ...
B. Novosyadlyj +7 more
core +1 more source
Matter coupling in partially constrained vielbein formulation of massive gravity [PDF]
, 2015 We consider a consistent linear effective vielbein matter coupling without introducing the Boulware-Deser ghost in ghost-free massive gravity. This is achieved in the partially constrained vielbein formulation.
De Felice, Antonio +3 more
core +2 more sources
de Sitter Excited State in Heterotic E8×E8${\rm E}_8 \times {\rm E}_8$ Theory
Fortschritte der Physik, EarlyView.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
wiley +1 more source
On the effect of renormalization group improvement on the cosmological power spectrum
European Physical Journal C: Particles and Fields, 2018 Asymptotically safe quantum gravity predicts running gravitational and cosmological constants, while it remains a meaningful quantum field theory because of the existence of a finite number of non-Gaussian ultraviolet fixed points.
R. Moti, A. Shojai
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Integrating multimodal data and machine learning for entrepreneurship research
Strategic Entrepreneurship Journal, EarlyView.Abstract Research Summary Extant research in neuroscience suggests that human perception is multimodal in nature—we model the world integrating diverse data sources such as sound, images, taste, and smell. Working in a dynamic environment, entrepreneurs are expected to draw on multimodal inputs in their decision making.
Yash Raj Shrestha, Vivianna Fang He
wiley +1 more source
Irregular universe in the Nieh-Yan modified teleparallel gravity
Physics Letters B, 2023 The Nieh-Yan modified teleparallel gravity is a model which modifies the general relativity equivalent teleparallel gravity by a coupling between the Nieh-Yan density and an axion-like field.
Mingzhe Li, Haomin Rao
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Cosmological perturbations in the inflationary Universe [PDF]
, 1997 Previously defined covariant and gauge-invariant perturbation variables, representing, e.g., the fractional spatial energy density gradient on hypersurfaces of constant expansion, are used to simplify the linear perturbation analysis of a classical ...
A. R. King +32 more
core +2 more sources
Journal of the Royal Anthropological Institute, EarlyView.Drawing on fieldwork conducted in a hospital in Greater Manchester, England in 2016–17, we describe how a set of national health priorities were translated into work for hospital managers and clinicians during a period of significant organizational pressure.
Adam Brisley +2 more
wiley +1 more source
Cosmological Perturbations in Phantom Dark Energy Models
Universe, 2017 The ΛCDM paradigm, characterised by a constant equation of state w = − 1 for dark energy, is the model that better fits observations. However, the same observations strongly support the possibility of a dark energy content where the corresponding
Imanol Albarran +2 more
doaj +1 more source