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Presentism and Quantum Gravity [PDF]

open access: yes, 2001
There is a philosophical tradition of arguing against presentism, the thesis that only presently existing things exist, on the basis of its incompatibility with fundamental physics.
Monton, Bradley
core  

Spacetime and the Philosophical Challenge of Quantum Gravity [PDF]

open access: yes, 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

open access: yesPhysics 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

Multi‐Scale Bionic Structure Constructs Biomass Flame‐Retardant Thermal Insulation Foam Material

open access: yesAdvanced 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

Anomalous radial acceleration of galaxies and clusters supports hyperconical modified gravity

open access: yes, 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

open access: yesPhysics Letters B
In 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

Challenges in connecting modified gravity theory and observations

open access: yesPhysical Review D, 2017
Cosmic acceleration may be due to modifications of cosmic gravity and to test this we need robust connections between theory and observations. However, in a model independent approach like effective field theory or a broad class like Horndeski gravity, several free functions of time enter the theory.
openaire   +3 more sources

Bio‐Inspired Gradient Coatings Enhance the Leading Edge Erosion Resistance of Wind Blades

open access: yesAdvanced 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

Time machines and traversable wormholes in modified theories of gravity

open access: yesEPJ 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

Blood Cell‐Camouflaged Liquid Metal Nanoconjugates Orchestrate Treg Depletion and STING‐Amplified Photothermal Immunity for Metastatic Triple‐Negative Breast Cancer Therapy

open access: yesAdvanced Science, EarlyView.
Whole‐blood biomimetic engineering transforms liquid metal nanoparticles into a tripartite immunotherapeutic platform that orchestrates regulatory T‐cell depletion, photothermal‐induced immunogenic cell death, and activation of the stimulator of interferon genes pathway.
Nina Sang, Eijiro Miyako
wiley   +1 more source

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