Results 11 to 20 of about 20,675 (71)

Heun Functions and Some of Their Applications in Physics

Advances in High Energy Physics, Volume 2018, Issue 1, 2018., 2018
Most of the theoretical physics known today is described by using a small number of differential equations. For linear systems, different forms of the hypergeometric or the confluent hypergeometric equations often suffice to describe the system studied.
M. Hortaçsu, Saber Zarrinkamar
wiley   +1 more source

Optimized Reputable Sensing Participants Extraction for Participatory Sensor Networks

Mathematical Problems in Engineering, Volume 2014, Issue 1, 2014., 2014
By collecting data via sensors embedded personal smart devices, sensing participants play a key role in participatory sensor networks. Using information provided by reputable sensing participants ensures the reliability of participatory sensing data.
Weiwei Yuan, Donghai Guan, Yuanfeng Jin, Lu Zhen   +3 more
wiley   +1 more source

From Physics Model to Results: An Optimizing Framework for Cross‐Architecture Code Generation

Scientific Programming, Volume 21, Issue 1-2, Page 1-16, 2013., 2013
Starting from a high‐level problem description in terms of partial differential equations using abstract tensor notation, the Chemora framework discretizes, optimizes, and generates complete high performance codes for a wide range of compute architectures. Chemora extends the capabilities of Cactus, facilitating the usage of large‐scale CPU/GPU systems
Marek Blazewicz, Ian Hinder, David M. Koppelman, Steven R. Brandt, Milosz Ciznicki, Michal Kierzynka, Frank Löffler, Erik Schnetter, Jian Tao   +8 more
wiley   +1 more source

Covariant action for bouncing cosmologies in modified Gauss-Bonnet gravity

, 2019
Cyclic universes with bouncing solutions are candidates for solving the big bang initial singularity problem. Here we seek bouncing solutions in a modified Gauss-Bonnet gravity theory, of the type $R+f(G)$, where $R$ is the Ricci scalar, $G$ is the Gauss-
Lemos, José P. S., Terrucha, Inês, Vernieri, Daniele   +2 more
core   +1 more source

Switching internal times and a new perspective on the 'wave function of the universe'

, 2019
Despite its importance in general relativity, a quantum notion of general covariance has not yet been established in quantum gravity and cosmology, where, given the a priori absence of coordinates, it is necessary to replace classical frames with ...
Hoehn, Philipp A
core   +1 more source

Hubble operator in isotropic loop quantum cosmology

, 2003
We present a construction of the Hubble operator for the spatially flat isotropic loop quantum cosmology. This operator is a Dirac observable on a subspace of the space of physical solutions.
Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M Vandersloot K, Date G, Dirac P A M, Fernando J, Gaul M, Golam Mortuza Hossain, Immirzi G, Kodama H, Misner C W, Perez A Rovelli C, Rovelli C, Rovelli C, Smolin L, Thiemann T, Thiemann T, Thiemann T   +26 more
core   +1 more source

The cosmological implications of a fundamental length: a DSR inspired de-Sitter spacetime

, 2008
We study a de-Sitter model in the framework of a Deformed Special Relativity (DSR) inspired structure. The effects of this framework appear as the existence of a fundamental length which influences the behavior of the scale factor.
Amelino-Camelia G, Amelino-Camelia G, Ashtekar A, Brandenberger R H, Carmona J M, Cheng T-P, Connes A, Green M, H R Sepangi, Khosravi N, Khosravi N Sepangi H R, Kowalski-Glikman J, Liddle A R, Magueijo J, Majid S, N Khosravi, Nascimento J R, Perkins D, Polchinski J, Rovelli C, Rovelli C, Seiberg N, Susskind L, Zachos C K   +23 more
core   +1 more source

Coherent states for FLRW space-times in loop quantum gravity

, 2011
We construct a class of coherent spin-network states that capture proprieties of curved space-times of the Friedmann-Lama\^itre-Robertson-Walker type on which they are peaked.
Abhay Ashtekar, Abhay Ashtekar, Antonino Marcianò, Carlo Rovelli, Claudio Perini, Elena Magliaro, Robert M. Wald, Thomas Thiemann   +7 more
core   +2 more sources

Nonmetricity formulation of general relativity and its scalar-tensor extension

, 2018
Einstein's celebrated theory of gravitation can be presented in three forms: general relativity, teleparallel gravity, and the rarely considered before symmetric teleparallel gravity.
Järv, Laur, Rünkla, Mihkel, Saal, Margus, Vilson, Ott   +3 more
core   +1 more source

The Semiclassical Limit of Loop Quantum Cosmology [PDF]

, 2001
The continuum and semiclassical limits of isotropic, spatially flat loop quantum cosmology are discussed, with an emphasis on the role played by the Barbero-Immirzi parameter \gamma in controlling space-time discreteness.
Ashtekar A, Ashtekar A, Ashtekar A, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bojowald M, Bombelli L, Bombelli L, Corichi A, Karasev M V, Martin Bojowald, Rovelli C, Sahlmann H, Thiemann T, Thiemann T, Varadarajan M   +20 more
core   +3 more sources