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61.
62.
Bikash Sinha 《Pramana》1989,32(4):523-539
The general characteristics of the transition from hadronic matter of nucleons, three quark bags, mesons of quark antiquark
pairs to quark gluon plasma is discussed. The phenomenological approach essentially guided by the MIT bag model and general
thermodynamic criteria of first-order phase transition is elaborated. The more realistic calculations using the QCD lattice
renormalization quark are touched upon. Possible signals of quark-gluon plasma are discussed. The central issue of deciphering
plasma signals from the signals of hot hadronic matter is discussed in detail.
The signals of the quark-gluon plasma, a subject of considerable interest in contemporary literature are focussed only on
(i) dileptons (ii) photon photon pairs and (iii)J/Ψ suppression (with special emphasis on CERN experiments). The lingering shadow of “EMC” effect is also mentioned.
Relics of the very early universe microseconds after the big bang in today’s universe (∼ 15 billion years later) are discussed.
Finally, the outlook of this very exciting field is presented, a purely personal viewpoint, generalized eventually to poetic
signals of the creation of the universe. 相似文献
63.
The total energy of the universe has been calculated assuming that it is the sum of the contributions from the matter part
and gravitational part. The calculations involve the use of Einstein pseudotensor. Calculations have been carried out in some
specific examples of spacetime geometries. In some cases the total energy is indeed zero confirming previous results but in
other cases the total energy is nonzero. So Rosen’s idea that the pseudotensorial calculations will lead to the result that
the total energy of the universe is zero, is very much model dependent. 相似文献
64.
R. Triay 《International Journal of Theoretical Physics》2003,42(6):1187-1192
The present speculation shows that a spatially closed geometry might be an alternative to Inflation scenario. 相似文献
65.
D. I. Savel’ev 《Mathematical Notes》2007,81(5-6):716-719
66.
Y. Baryshnikov P. Jelenkovi? P. Mom?ilovi? D. Rubenstein 《Operations Research Letters》2004,32(3):199-206
We consider flood search on a line and show that no algorithm can achieve an average-case competitive ratio of less than 4 when compared to the optimal off-line algorithm. We also demonstrate that the optimal scanning sequences are described by simple recursive relationships that yield surprisingly complex behavior related to Hamiltonian chaos. 相似文献
67.
Edson de Faria 《Proceedings of the American Mathematical Society》1996,124(6):1949-1957
In this paper we examine a result of D. Sullivan according to which two expanding endomorphisms of the circle are conjugate as soon as they are symmetrically conjugate. We develop general a priori estimates on the local distortion of quasisymmetric mappings and combine them with the classical naive distortion lemma to present a complete proof of Sullivan's result. A new proof is offered at the end that renders unnecessary the use of Markov partitions or the control of eigenvalues at periodic points.
68.
69.
M. A. Mestvirishvili K. A. Modestov Yu. V. Chugreev 《Theoretical and Mathematical Physics》2007,152(3):1342-1350
We propose a variant of the quintessence theory in order to obtain an accelerated expansion of the Friedmann universe in the
framework of the relativistic theory of gravity. The scalar field of dark energy creates the substance of quintessence. We
show that the function V(Φ) that factors the Lagrangian of the scalar field Φ does not influence the evolution of the universe.
We find some relations that allow finding the explicit time-dependence of Φ if only the function V(Φ) is chosen.
__________
Translated from Teoreticheskaya i Matematicheskaya Fizika, Vol. 152, No. 3, pp. 551–560, September, 2007. 相似文献
70.
Cosmological models with two interacting fluids, each satisfying the strong energy condition, are studied in the framework
of classical General Relativity. If the interactions are phenomenologically described by a power law in the scale factor,
the two initial interacting fluids can be equivalently substituted by two non interacting effective fluids, where one of them
may violate the strong energy condition and/or have negative energy density. Analytical solutions of the Friedmann equations
of this general setting are obtained and studied. One may have, depending on the scale where the interaction becomes important,
non singular universes with early accelerated phase, or singular models with transition from decelerated to accelerated expansion
at large scales. Among the first, there are bouncing models where contraction is stopped by the interaction. In the second
case, one obtains dark energy expansion rates without dark energy, like ΛCDM or phantomic accelerated expansions without cosmological
constant or phantoms, respectively.
We would like to thank CNPq of Brazil for financial support. One of us (NPN) would like to thank the French/Brazillian cooperation
CAPES/COFECUB for partial financial support. We would also like to thank ‘Pequeno Seminario’ of CBPF’s Cosmology Group for
useful discussions. 相似文献