Zobrazeno 1 - 10
of 16
pro vyhledávání: '"Dumitru N. Vulcanov"'
Autor:
Dumitru N. Vulcanov
Publikováno v:
TIM 19 PHYSICS CONFERENCE.
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::f73219ef1a923c0b0c246c530316672d
https://doi.org/10.1063/5.0001073
https://doi.org/10.1063/5.0001073
Publikováno v:
Annals of West University of Timisoara: Physics, Vol 56, Iss 1, Pp 139-144 (2012)
The article presents some new aspects and experience on the use of computer in teaching general relativity and cosmology for undergraduate students (and not only) with some experience in computer manipulation. Some years ago certain results were repo
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::a4c8324f5d29f492b97d24a28d076b17
https://doaj.org/article/d1f72a4241e449bbb99fd4ccfb3612d2
https://doaj.org/article/d1f72a4241e449bbb99fd4ccfb3612d2
Autor:
Dumitru N. Vulcanov
Publikováno v:
Open Physics, Vol 6, Iss 1, Pp 84-96 (2008)
The method of “reverse engineering” for designing potentials in cosmologies with “quintessence” scalar field is systematically used for several types of cosmologies (through the time behavior of the scale factor). The general recipe is introd
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::7025dad48e0536a65f2718f7e1b8d0a6
https://doaj.org/article/ed1472f901a146fea74db656b4445523
https://doaj.org/article/ed1472f901a146fea74db656b4445523
Autor:
Dumitru N. Vulcanov
Publikováno v:
Computer Physics Communications. 154:205-218
The article presents computer algebra procedures and routines applied to the study of the Dirac field on curved spacetimes. The main part of the procedures is devoted to the construction of Pauli and Dirac matrices algebra on an anholonomic orthonorm
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::5b0fec0e44f6fc0c7ffe610042e0f0d6
https://doi.org/10.1016/s0010-4655(03)00344-8
https://doi.org/10.1016/s0010-4655(03)00344-8
Autor:
Dumitru N. Vulcanov, F.A. Ghergu
Publikováno v:
Computing in Science & Engineering. 3:65-70
The authors' department considers general relativity (GR) teaching a necessity for midlevel graduate physics students, so we introduce a GR course at the third-year undergraduate level. During the last two years, we have used several packages in the
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::f14497261f5d9af3feb8f53bdfc0c239
https://doi.org/10.1109/5992.909005
https://doi.org/10.1109/5992.909005
Autor:
Dumitru N. Vulcanov, Ion I. Cotaescu
Publikováno v:
Europhysics Letters (EPL). 49:156-161
It is shown that in general relativity some static metrics are able to simulate oscillatory motions. Their form depends on two arbitrary real parameters which determine the specific oscillation modes. The conclusion is that these metrics can be used
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_dedup___::fedadd11029900b0344d323e6f4b667f
https://doi.org/10.1209/epl/i2000-00100-3
https://doi.org/10.1209/epl/i2000-00100-3
Autor:
Dumitru N. Vulcanov
Publikováno v:
International Journal of Modern Physics C. :103-111
We present new procedures in REDUCE language using the EXCALC package (adapted for IBM-PC machines) for algebraic programming in the hamiltonian formulation of Einstein–Maxwell equations. The dynamic and the constraint equations containing specific
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::a16c9c486f151bbba58844c449db0151
https://doi.org/10.1142/s0129183198000091
https://doi.org/10.1142/s0129183198000091
Publikováno v:
AIP Conference Proceedings.
We consider a class of tachyon-like potentials, motivated by string theory, D-brane dynamics and inflation theory in the context of classical and quantum mechanics. A formalism for describing dynamics of tachyon fields in spatially homogenous and one
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::90b168023ddb912e9cd79761abb65acd
https://doi.org/10.1063/1.4903007
https://doi.org/10.1063/1.4903007
Autor:
Dumitru N. Vulcanov, Ion I. Cotaescu
Publikováno v:
International Journal of Modern Physics C. :273-286
We present new procedures in the REDUCE language for algebraic programming of the Dirac equation on curved space-time. The main part of the program is a package of routines defining the Pauli and Dirac matrix algebras. Then the Dirac equation is obta
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::d945ce2f7433a7cc324f7003bacda090
https://doi.org/10.1142/s0129183197000254
https://doi.org/10.1142/s0129183197000254
Autor:
Ion I. Cotaescu, Dumitru N. Vulcanov
Publikováno v:
International Journal of Modern Physics C. :345-359
The article presents some new results obtained for the non-relativistic approximation of the Dirac equation in a non-inertial reference frame — rotated and accelerated — and in Schwarzschild gravitational field. These results are obtained with ne
Externí odkaz:
https://explore.openaire.eu/search/publication?articleId=doi_________::ca698e2d933c17856ec28213644d74a8
https://doi.org/10.1142/s0129183197000291
https://doi.org/10.1142/s0129183197000291