Results 41 to 50 of about 22,331 (301)
New effective coupled $$F(^{(4)}\!R,\varphi )$$ F ( ( 4 ) R , φ ) modified gravity from $$f(^{(5)}\!R)$$ f ( ( 5 ) R ) gravity in five dimensions [PDF]
, 2015 Using some ideas of the Wesson induced matter theory, we obtain a new kind of $$F(^{(4)}\!R,\varphi )$$ modified gravity theory as an effective four-dimensional (4D) theory derived from $$f(^{(5)}\!R)$$ gravity in five dimensions (5D).
José Edgar Madriz Aguilar
core +1 more source
$$f(\mathcal {R},\varphi ,\chi )$$ f(R,φ,χ) cosmology with Noether symmetry
European Physical Journal C: Particles and Fields, 2020 This paper is devoted to explore modified $$f(\mathcal {R})$$ f(R) theories of gravity using Noether symmetry approach. For this purpose, Friedmann–Robertson–Walker spacetime is chosen to investigate the cosmic evolution. The study is mainly divided into
M. Farasat Shamir
doaj +1 more source
European Physical Journal C: Particles and Fields, 2020 In this work we analyze hydrostatic equilibrium configurations of neutron stars in a non-minimal geometry-matter coupling (GMC) theory of gravity. We begin with the derivation of the hydrostatic equilibrium equations for the f(R, L) gravity theory, where
G. A. Carvalho +4 more
doaj +1 more source
Arthritis Care &Research, EarlyView.Objective Studies of damage accrual in patients with systemic lupus erythematosus (SLE) show associations with disease activity measured by the SLE Disease Activity Index 2000 (SLEDAI‐2K), but these associations are imperfect. SLEDAI scores are powerfully influenced by weightings (1–8) assigned to each domain.
Kevin Zhang +8 more
wiley +1 more source
Thermodynamics in Modified Gravity with Curvature Matter Coupling
Advances in High Energy Physics, 2013 The first and generalized second laws of thermodynamics are studied in f(R,Lm) gravity, a more general modified theory with curvature matter coupling. It is found that one can translate the Friedmann equations to the form of first law accompanied with ...
M. Sharif, M. Zubair
doaj +1 more source
Cosmological Bounce and Some Other Solutions in Exponential Gravity
Universe, 2018 In this work, we present some cosmologically relevant solutions using the spatially flat Friedmann-Lemaitre-Robertson-Walker (FLRW) spacetime in metric f ( R ) gravity where the form of the gravitational Lagrangian is given by 1 α e
Pritha Bari +2 more
doaj +1 more source
Advanced Engineering Materials, EarlyView.A novel workflow for investigating hydride vapor phase epitaxy for GaN bulk crystal growth is proposed. It combines Design of experiments (DoE) with physical simulations of mass transport and crystal growth kinetics, serving as an intermediate step between DoE and experiments.
J. Tomkovič +7 more
wiley +1 more source
Gravitational Wave Polarizations in f (R) Gravity and Scalar-Tensor Theory
EPJ Web of Conferences, 2018 The detection of gravitational waves by the Laser Interferometer Gravitational-Wave Observatory opens a new era to use gravitational waves to test alternative theories of gravity.
Gong Yungui, Hou Shaoqi
doaj +1 more source
Effective actions for loop quantum cosmology in fourth-order gravity
European Physical Journal C: Particles and Fields, 2021 Loop quantum cosmology (LQC) is a theory which renders the Big Bang initial singularity into a quantum bounce, by means of short-range repulsive quantum effects at the Planck scale.
Marcello Miranda +3 more
doaj +1 more source
Journal and proceedings of the Royal Society of New South Wales, 2008 (Uploaded by Plazi from the Biodiversity Heritage Library) No abstract provided.
openaire +2 more sources