Results 121 to 130 of about 167,529,233 (288)
Spacetime and the Philosophical Challenge of Quantum Gravity [PDF]
, 2001 We survey some philosophical aspects of the search for a quantum theory of gravity, emphasising how quantum gravity throws into doubt the treatment of spacetime common to the two `ingredient theories' (quantum theory and general relativity), as a 4 ...
Butterfield, Jeremy +3 more
core +1 more source
On the scalar-vector-tensor gravity: Black hole, thermodynamics and geometrothermodynamics
Physics Letters B, 2018 Recently, a new class of modified gravity theories formulated via an additional scalar and vector field on top of the standard tensor field has been proposed.
Phongpichit Channuie, Davood Momeni
doaj +1 more source
Halide Perovskite: A Rich Source of Thermal Insulator
Advanced Science, EarlyView.Halide perovskites exhibit ultralow thermal conductivity driven by intrinsic lattice softness and strong anharmonicity, falling below conventional defect‐engineering limits. Weak metavalent bonding, A‐site rattling, and dynamic octahedral tilting drive phonon scattering to the Ioffe–Regel limit, where wave‐like tunneling replaces particle‐like ...
Haolin Ye +3 more
wiley +1 more source
Anomalous radial acceleration of galaxies and clusters supports hyperconical modified gravity
, 2014 General relativity (GR) is the most successful theory of gravity, with great observational support at local scales. However, to keep GR valid at over cosmic scales, some phenomena (such as the flat galaxy rotation curves and the cosmic acceleration ...
Monjo Agut, Robert, Banik, Indranil
core +1 more source
Birkhoff’s theorem and uniqueness: A peek beyond general relativity
Physics Letters BIn General Relativity, Birkhoff’s theorem asserts that any spherically symmetric vacuum solution must be static and asymptotically flat. In this paper, we study the validity of Birkhoff’s theorem for a broad class of modified gravity theories in four ...
Rajes Ghosh +2 more
doaj +1 more source
Advanced Science, EarlyView.Schematic representation of ultrasound‐mediated ICG/siCD24@MSN‐LCD from nanostructure to synergistic sono‐gene therapy. This nanoplatform targets ASGPR via the LCD shell, which dissociates to release loaded ICG and siCD24. The core mechanism involves ultrasound‐guided sonodynamic therapy by ICG and CD24 knockdown by siCD24, both activating the p53 axis
Yading Zhao +11 more
wiley +1 more source
Time machines and traversable wormholes in modified theories of gravity
EPJ Web of Conferences, 2013 We review recent work on wormhole geometries in the context of modified theories of gravity, in particular, in f(R) gravity and with a nonminimal curvature-matter coupling, and in the recently proposed hybrid metric-Palatini theory.
Lobo Francisco S.N.
doaj +1 more source
Multi‐Scale Bionic Structure Constructs Biomass Flame‐Retardant Thermal Insulation Foam Material
Advanced Science, EarlyView.Inspired by mussel adhesion and hierarchical brick‐and‐mortar architectures, a cellulose‐based biomimetic foam is constructed by anchoring bentonite nanosheets onto a polydopamine‐decorated cellulose nanofiber network. The resulting foam combines low thermal conductivity with intrinsic flame retardancy and full biodegradability, presenting a ...
Jianming Liao +10 more
wiley +1 more source
Modified Gravity as Entropic Cosmology
UniverseThe present work reveals a direct correspondence between modified theories of gravity (cosmology) and entropic cosmology based on the thermodynamics of apparent horizon.
Shin’ichi Nojiri +3 more
doaj +1 more source
Bio‐Inspired Gradient Coatings Enhance the Leading Edge Erosion Resistance of Wind Blades
Advanced Science, EarlyView.Rain‐induced erosion of the wind turbine blade leading edge poses a critical challenge to maintenance and operation. Here, we propose a bio‐inspired approach for erosion protection utilising a platelet‐reinforced polyurethane coating with a graded through‐thickness architecture.
Natalia Sofia Guevara‐Sotelo +2 more
wiley +1 more source