A minimal Length Uncertainty Approach to Cosmological Constant Problem
Abdel Magied Diab, Abdel Nasser Tawfik
备注：
5 pages, 0 figures, an invited talk given at the int. Workshop on Astronomy and Relativistic Astrophysics (IWARA $2020$ Video Conference), accepted for publication in Astronomische Nachrichten
Based on quantum mechanical framework for the minimal length uncertainty, we demonstrate that the generalized uncertainty principle (GUP) parameter could be best constrained by recent gravitational waves observations on one hand. On other hand this suggests modified dispersion relations (MDRs) enabling an estimation for the difference between the group velocity of gravitons and that of photons. Utilizing features of the UV/IR correspondence and the obvious similarities between GUP (including non-gravitating and gravitating impacts on Heisenberg uncertainty principle) and the discrepancy between the theoretical and the observed cosmological constant (apparently manifesting gravitational influences on the vacuum energy density), we suggest a possible solution for the cosmological constant problem.
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On the basis of a qualitative and numerical analysis of a cosmological model based on an asymmetric scalar doublet of nonlinear, minimally interacting scalar fields -- one classical and one phantom, peculiarities of the behavior of the model near zero energy hypersurfaces have been revealed. Numerical models have been constructed, in which the dynamical system has limit cycles on the zero-energy hypersurfaces. Three types of behavior of the cosmological model have been distinguished, configured by the fundamental constants of the scalar fields and the initial conditions. It is shown that over …
On the basis of a qualitative and numerical analysis of a cosmological model based on an asymmetric scalar doublet of nonlinear, minimally interacting scalar fields, both classical and phantom, the behavior of the model near zero energy hypersurfaces has been revealed. The influence of the multiply connected factor of the phase space of the dynamical system, this factor being a consequence of the nonanalyticity of the coefficients of an autonomous system of differential equations, is discussed. The character of all singular points is revealed.
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Cosmological Constraints on the Generalized Uncertainty Principle from Redshift-Space Distortions
Durban University of Technology（德班理工大学）；North-West University（西北大学）；Universidad Catòlica del Norte（北天主教大学）；National Institute for Theoretical and Computational Sciences (NITheCS)（国家理论与计算科学研究所）
We propose an improved exponential Generalized Uncertainty Principle (GUP) by introducing a positive integer $n$ called the suppressing index. Due to the UV/IR mixing brought by the GUP, the states with momenta smaller than the critical momentum ($P < P_{\rm Crit}$) are canceled by the states with momenta larger than the critical momentum ($P > P_{\rm Crit}$) and thus have no contributions to the energy density of the vacuum. By considering the contributions just from the states with momenta larger than the critical momentum ($P > P_{\rm Crit}$) and choosing a suitable suppressing index, $n \s…
