相关论文: A relation between the Barbero-Immirzi parameter a…
The Ashtekar-Barbero-Immirzi formulation of General Relativity is extended to include spinor matter fields. Our formulation applies to generic values of the Immirzi parameter and reduces to the Ashtekar-Romano-Tate approach when the Immirzi…
The success of a given inflationary model crucially depends upon two features: its predictions for observables such as those of the Cosmic Microwave background (CMB) and its insensitivity to the unknown ultraviolet (UV) physics such as…
We embed second class constrained systems by a formalism that combines concepts of the BFFT method and the unfixing gauge formalism. As a result, we obtain a gauge-invariant system where the introduction of the Wess-Zumino (WZ) field is…
Using the data from SNO NCD phase, SuperK, Borexino and KamLAND Solar phase, we derive in a model independent way, bounds on the possible components in the solar neutrino flux. We update the limits on the antineutrino ($\bar\nu_x$) flux and…
The Hawking radiation is one of the most interesting phenomena predicted by the theory of quantum field in curved space. The origin of Hawking radiation is closely related to the fact that a particle which marginally escapes from collapsing…
The canonical one-band Hubbard model is studied using a computational method that mixes the Monte Carlo procedure with the mean field approximation. This technique allows us to incorporate thermal fluctuations and the development of…
Invariants at arbitrary and fixed energy (strongly and weakly conserved quantities) for 2-dimensional Hamiltonian systems are treated in a unified way. This is achieved by utilizing the Jacobi metric geometrization of the dynamics. Using…
We study the accelerated expansion phase of the universe by using the {\textit{kinematic approach}}. In particular, the deceleration parameter $q$ is parametrized in a model-independent way. Considering a generalized parametrization for…
In this paper, we analyse a curvature- and torsion-square quantum gravity action with an additional Holst term minimally coupled to a massive Dirac field in four dimensions. The main purpose here is to try to estimate and compare the value…
The predictions of Standard Model Higgs inflation are in excellent agreement with the Planck data, without the need for new fields. However, consistency of the theory requires the presence of (unknown) threshold corrections. These modify…
We analyze the exclusive rare $B \to K^{(*)} \ell^+ \ell^-$, $B \to K^{(*)} \nu \bar \nu$ and $B \to K^* \gamma$ decays in the Applequist-Cheng-Dobrescu model, an extension of the Standard Model in presence of universal extra dimensions. In…
A mechanism of radiatively induced breaking of the conformal symmetry in the Standard Model is suggested. The system of one scalar (Higgs) and one fermion (top-quark) fields with Yukawa and $\phi^4$ interactions is considered. The infrared…
It is shown that the commonly accepted definition for the Casimir scalar operators of the Poincare group does not satisfy the properties of Casimir invariance when applied to the non-inertial motion of elementary particles while in the…
The spacetime dependent lagrangian formalism of references [1-2] is used to obtain a classical solution of Yang-Mills theory. This is then used to obtain an estimate of the vacuum expectation value of the Higgs field, viz. $\phi_{a}=A/e$,…
We rederive the thermodynamical properties of a non interacting gas in the presence of a minimal uncertainty in length. Apart from the phase space measure which is modified due to a change of the Heisenberg uncertainty relations, the…
We consider a class of toy models describing a fermion field coupled with a boson field. The model can be viewed as a Yukawa model but with scalar fermions. As in our first paper, the interaction kernels are assumed bounded in the fermionic…
We consider the question of removing the ultraviolet cutoff in a 2D Quantum Field Theory with an interaction term which is non-renormalizable by power counting. This model arises as the first non-trivial correction beyond the Gaussian…
The key elements of the Unified Model are reviewed and checked against modern experimental data. For medium-mass or heavy nuclei it is found that separation between collective and intrinsic degrees freedom becomes invalid for after exciting…
An imroved standard solar model, with more accurate input parameters and more accurate treatment of plasma physics effects, predicts a solar neutrino flux which is consistent within experimental uncertainties with the solar neutrino…
The quantization of the chiral Schwinger model $(\chi QED_{2})$ with one-parameter class Faddeevian regularization is hampered by the chiral anomaly, i.e., the Gauss law commutator exhibits Faddeev's anomaly. To overcome this kind of…