Results 61 to 70 of about 129,163 (322)
Quantum Gravity in Everyday Life: General Relativity as an Effective Field Theory
Living Reviews in Relativity, 2004 This article is meant as a summary and introduction to the ideas of effective field theory as applied to gravitational systems, ideas which provide the theoretical foundations for the modern use of general relativity as a theory from which precise ...
Burgess Cliff P.
doaj
Hidden quantum group structure in Einstein's general relativity [PDF]
Nuclear Physics B, 1998 A new formal scheme is presented in which Einstein's classical theory of General Relativity appears as the common, invariant sector of a one-parameter family of different theories. This is achieved by replacing the Poincare` group of the ordinary tetrad formalism with a q-deformed Poincare` group, the usual theory being recovered at q=1.
BIMONTE, GIUSEPPE ROBERTO +3 more
openaire +4 more sources
Advanced Functional Materials, EarlyView.This study presents novel anti‐counterfeiting tags with multilevel security features that utilize additional disguise features. They combine luminescent nanosized Ln‐MOFs with conductive polymers to multifunctional mixed‐matrix membranes and powder composites. The materials exhibit visible/NIR emission and matrix‐based conductivity even as black bodies.
Moritz Maxeiner +9 more
wiley +1 more source
Perturbative Quantum Gravity and its Relation to Gauge Theory
Living Reviews in Relativity, 2002 In this review we describe a non-trivial relationship between perturbative gauge theory and gravity scattering amplitudes. At the semi-classical or tree-level, the scattering amplitudes of gravity theories in flat space can be expressed as a sum of ...
Bern Zvi
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A fundamental problem in quantizing general relativity
, 2018 We point out a fundamental problem that hinders the quantization of general relativity: quantum mechanics is formulated in terms of systems, typically limited in space but infinitely extended in time, while general relativity is formulated in terms of ...
Maccone, Lorenzo
core +1 more source
CLASSICAL AND QUANTUM GENERAL RELATIVITY: A NEW PARADIGM [PDF]
International Journal of Modern Physics D, 2005 We argue that recent developments in discretizations of classical and quantum gravity imply a new paradigm for doing research in these areas. The paradigm consists in discretizing the theory in such a way that the resulting discrete theory has no constraints. This solves many of the hard conceptual problems of quantum gravity.
Gambini, Rodolfo, Pullin, Jorge
openaire +3 more sources
Synchrotron Radiation for Quantum Technology
Advanced Functional Materials, EarlyView.Materials and interfaces underpin quantum technologies, with synchrotron and FEL methods key to understanding and optimizing them. Advances span superconducting and semiconducting qubits, 2D materials, and topological systems, where strain, defects, and interfaces govern performance.
Oliver Rader +10 more
wiley +1 more source
Discrete Approaches to Quantum Gravity in Four Dimensions
Living Reviews in Relativity, 1998 The construction of a consistent theory of quantum gravity is a problem in theoretical physics that has so far defied all attempts at resolution. One ansatz to try to obtain a non-trivial quantum theory proceeds via a discretization of space-time and the
Loll Renate
doaj
Quantum Black Holes and (Re)Solution of the Singularity
Universe, 2021 Classical general relativity predicts the occurrence of spacetime singularities under very general conditions. Starting from the idea that the spacetime geometry must be described by suitable states in the complete quantum theory of matter and gravity ...
Roberto Casadio
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Advanced Functional Materials, EarlyView.HKUST‐1/TiO2 composite materials show a very high photocatalytic hydrogen evolution rate which increases as a function of the irradiation time until reaching a plateau and even surpasses the performance of the 1%Pt/TiO2 material after three photocatalytic cycles.
Alisha Khan +9 more
wiley +1 more source