Zobrazeno 1 - 10
of 266
pro vyhledávání: '"Martin Bojowald"'
Autor:
Martin Bojowald, Erick I. Duque
Publikováno v:
Physics Letters B, Vol 847, Iss , Pp 138279- (2023)
A new class of modified gravity theories, made possible by subtle features of the canonical formulation of general covariance, naturally allows MOND-like behavior (MOdified Newtonian Dynamics) in effective space-time solutions without introducing new
Externí odkaz:
https://doaj.org/article/8999c0b3745c4bdca473338de85f1f3a
Autor:
Martin Bojowald, Artur Tsobanjan
Publikováno v:
Quantum Reports, Vol 5, Iss 1, Pp 22-37 (2022)
Quantum reference frames are expected to differ from classical reference frames because they have to implement typical quantum features such as fluctuations and correlations. Here, we show that fluctuations and correlations of reference variables, in
Externí odkaz:
https://doaj.org/article/cbb676cab2454b6c9f14444c324f15de
Publikováno v:
Physics Letters B, Vol 816, Iss , Pp 136193- (2021)
The Higgs field is an attractive candidate for the inflaton because it is an observationally confirmed fundamental scalar field. Importantly, it can be modeled by the most general renormalizable scalar potential. However, if the classical Higgs poten
Externí odkaz:
https://doaj.org/article/e40757104b084b469b13280add59723f
Autor:
Martin Bojowald
Publikováno v:
Universe, Vol 8, Iss 3, p 184 (2022)
In canonical gravity, general covariance is implemented by hypersurface-deformation symmetries on thephase space. The different versions of hypersurface deformations required for full covariance have complicated interplays with one another, governed
Externí odkaz:
https://doaj.org/article/8b15c3518e614bcfafb8192b2fcb2089
Autor:
Martin Bojowald
Publikováno v:
Universe, Vol 7, Iss 7, p 251 (2021)
Background independence is often emphasized as an important property of a quantum theory of gravity that takes seriously the geometrical nature of general relativity. In a background-independent formulation, quantum gravity should determine not only
Externí odkaz:
https://doaj.org/article/0e935a2018c3467d81f96f39aee0da31
Autor:
Martin Bojowald
Publikováno v:
Universe, Vol 7, Iss 6, p 186 (2021)
Loop quantum cosmology is a conflicted field in which exuberant claims of observability coexist with serious objections against the conceptual and physical viability of its current formulations. This contribution presents a non-technical case study o
Externí odkaz:
https://doaj.org/article/23ba856e1078488cbc2550c827ff6db5
Publikováno v:
Journal of High Energy Physics, Vol 2017, Iss 4, Pp 1-18 (2017)
Abstract Non-associative algebras appear in some quantum-mechanical systems, for instance if a charged particle in a distribution of magnetic monopoles is considered. Using methods of deformation quantization it is shown here, that algebras for such
Externí odkaz:
https://doaj.org/article/1fe1bb28c26b4270aa2abcabbe6b4041
Autor:
Martin Bojowald
Publikováno v:
Universe, Vol 6, Iss 8, p 125 (2020)
Dynamical black-hole scenarios have been developed in loop quantum gravity in various ways, combining results from mini and midisuperspace models. In the past, the underlying geometry of space-time has often been expressed in terms of line elements w
Externí odkaz:
https://doaj.org/article/8c77356b980a403590b4ebb2112958c2
Autor:
Martin Bojowald
Publikováno v:
Universe, Vol 6, Iss 3, p 36 (2020)
A large number of models have been analyzed in loop quantum cosmology, using mainly minisuperspace constructions and perturbations. At the same time, general physics principles from effective field theory and covariance have often been ignored. A con
Externí odkaz:
https://doaj.org/article/aa18e84923fb434abaf750b3179cfdbc
Autor:
Martin Bojowald
Publikováno v:
Mathematics, Vol 7, Iss 7, p 645 (2019)
In loop quantum cosmology, the values of volume fluctuations and correlations determine whether the dynamics of an evolving state exhibits a bounce. Of particular interest are states that are supported only on either the positive or the negative part
Externí odkaz:
https://doaj.org/article/861029ea8de3465db0c3cf54c4d10d0c