Zobrazeno 1 - 10
of 39
pro vyhledávání: '"Michiyasu Nagasawa"'
Autor:
Michiyasu Nagasawa
Publikováno v:
Symmetry, Integrability and Geometry: Methods and Applications, Vol 6, p 053 (2010)
Cosmological phase transitions accompanied by some kind of symmetry breaking would cause the creation of topological defects and the resulting production of primordial magnetic field. Moreover, such a procedure inevitably affects the cosmic backgroun
Externí odkaz:
https://doaj.org/article/4ed077f05e984690851459f7fcbab2ba
Autor:
Michiyasu, Nagasawa
Primordial black hole formation by cosmic string collapse is reconsidered when the winding number of the string is larger than the unity. The line energy density of the multiple winding string becomes greater than that of the single winding string so
Externí odkaz:
http://arxiv.org/abs/astro-ph/0011482
Autor:
Ryouta Matsuyama, Michiyasu Nagasawa
Publikováno v:
Journal of Physics: Conference Series. 1468:012006
A noncommutative gravitational theory constructed by applying Moyal deformation quantization and the Seiberg–Witten map to teleparallel gravity shows that gravity acts repulsively in an extreme region where its quantum effects become prominent. The
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ceeb5591bb4b6fb2b8914ce94f9bdb54
https://doi.org/10.1088/1742-6596/1468/1/012006
https://doi.org/10.1088/1742-6596/1468/1/012006
Autor:
Ryouta Matsuyama, Michiyasu Nagasawa
In this paper, a noncommutative gravitational theory is constructed by applying Moyal deformation quantization and the Seiberg-Witten map to teleparallel gravity, a classical gravitational theory, as a gauge theory of local translational symmetry. Si
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::34e8abcd4b0f905ef240e2031ac6e61c
Autor:
Michiyasu Nagasawa
Publikováno v:
International Journal of Modern Physics A. 22:5785-5799
The production and evolution of cosmological defects are investigated based on the standard particle physics theory such as the electroweak unified model and quantum chromodynamics. In these models, the string type solution can be obtained. Although
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5fe844d032663685b1a9e6a55aac3ae1
https://doi.org/10.1142/s0217751x07039018
https://doi.org/10.1142/s0217751x07039018
Autor:
Michiyasu Nagasawa
Publikováno v:
General Relativity and Gravitation. 37:1635-1649
Primordial black hole formation by cosmic string collapses is reconsidered in the case where the winding number of the string is larger than unity. The line energy density of a multiple winding string becomes greater than that of a single winding str
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::68a994abd01ed944bfd02050db9eaf1c
https://doi.org/10.1007/s10714-005-0141-9
https://doi.org/10.1007/s10714-005-0141-9
Autor:
Michiyasu Nagasawa
Publikováno v:
Nuclear Physics B - Proceedings Supplements. 136:356-361
If some kinds of symmetry breaking occur at the cosmological phase transition, the production of topological and/or non-topological defects can be expected. Within the core of such defects, symmetric states, that is, the high energy states where the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::49fefcb77a0159d24d044797e256be02
https://doi.org/10.1016/j.nuclphysbps.2004.10.017
https://doi.org/10.1016/j.nuclphysbps.2004.10.017
Publikováno v:
Physics Letters B. 467:205-210
In models in which some of the scalar field are charged and some uncharged, interactions with a finite temperature plasma will lead to corrections to the effective potential of the charged fields which may stabilize embedded defects made up of unchar
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3fba485cdeb1a932fbcb999ade0bb332
https://doi.org/10.1016/s0370-2693(99)01140-5
https://doi.org/10.1016/s0370-2693(99)01140-5
Autor:
Michiyasu Nagasawa
Publikováno v:
Nuclear Physics B - Proceedings Supplements. 72:94-98
When the amount of the axion emitted from the axionic string and the axionic domain wall is evaluated, the number density of the source string should be necessarily determined. Although it is the simplest assumption that the axionic string obeys the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::357e530326887d96552981d387b5a91d
https://doi.org/10.1016/s0920-5632(98)00509-x
https://doi.org/10.1016/s0920-5632(98)00509-x
Autor:
Michiyasu Nagasawa
Publikováno v:
Progress of Theoretical Physics. 98:851-867
The damping of the axionic string motion due to the surrounding plasma is estimated by a detailed calculation of the fermion scatter from a global string and it is shown that the friction force on the string can be neglected before the axionic domain
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::3ec1c752cac0416c900e2b0d5b4cb2e5
https://doi.org/10.1143/ptp.98.851
https://doi.org/10.1143/ptp.98.851