scholarly journals Dilatonic gravity near two dimensions and asymptotic freedom of the gravitational coupling constant

1995 ◽  
Vol 347 (3-4) ◽  
pp. 211-216 ◽  
Author(s):  
E Elizalde ◽  
S.D Odintsov
1995 ◽  
Vol 10 (21) ◽  
pp. 1507-1519 ◽  
Author(s):  
E. ELIZALDE ◽  
S.D. ODINTSOV

We study a renormalizable, general theory of dilatonic gravity (with a kinetic-like term for the dilaton) interacting with scalar matter near two dimensions. The one-loop effective action and the beta functions for this general theory are written down. It is proven that the theory possesses a nontrivial uv fixed point which yields an asymptotically free gravitational coupling constant (at ε→0) in this regime. Moreover, at the fixed point the theory can be cast under the form of a string-inspired model with free scalar matter. The renormalization of the Jackiw-Teitelboim model and of lineal gravity in 2+ε dimensions is also discussed. We show that these two theories are distinguished at the quantum level. Finally, fermion-dilatonic gravity near two dimensions is considered.


1995 ◽  
Vol 10 (19) ◽  
pp. 1351-1363 ◽  
Author(s):  
TOSHIAKI AIDA ◽  
YOSHIHISA KITAZAWA

We evaluate the quantum corrections of the Einstein-Hilbert action with boundaries in (2+ε)-dimensional expansion approach. We find the Einstein-Hilbert action with boundaries to be renormalizable to the one-loop order. We compute the geometric entropy beyond the semiclassical approximation. It is found that the exact geometric entropy is related to the string susceptibility by the analytic continuation in the central charge. Our results also show that we can renormalize the divergent quantum corrections for the Bekenstein-Hawking entropy of black holes by the gravitational coupling constant renormalization beyond two dimensions.


Galaxies ◽  
2019 ◽  
Vol 7 (1) ◽  
pp. 38
Author(s):  
Ismael Ayuso ◽  
José Mimoso ◽  
Nelson Nunes

In this work, we seek a cosmological mechanism that may define the sign of the effective gravitational coupling constant, G. To this end, we consider general scalar-tensor gravity theories as they provide the field theory natural framework for the variation of the gravitational coupling. We find that models with a quadratic potential naturally stabilize the value of G into the positive branch of the evolution and further, that de Sitter inflation and a relaxation to General Relativity is easily attained.


1975 ◽  
Vol 53 (20) ◽  
pp. 2306-2311 ◽  
Author(s):  
G. Papini ◽  
S. -R. Valluri

The cross sections for the process of photoproduction of gravitons in Coulomb and magnetic dipole external fields have been calculated. The calculation, which is linear in the gravitational coupling constant κ, is completely covariant, manifestly gauge invariant, and divergence free. The results to this order in κ are exact. Expressions for the case of extended sources have also been obtained and found to be in agreement with the results of other authors.


2011 ◽  
Vol 26 (17) ◽  
pp. 1301-1308 ◽  
Author(s):  
F. R. KLINKHAMER

A previous calculation of Newton's gravitational coupling constant G is generalized. This generalization makes it possible to have "atoms of two-dimensional space" with an integer dimension d atom of the internal space, where the case d atom = 1 is found to be excluded. Given the quantum of area l2, the final formula for G is inversely proportional to the logarithm of the integer d atom . The generalization used may be interpreted as a modification of the energy equipartition law of the microscopic degrees of freedom responsible for gravity, suggesting some form of long-range interaction between these degrees of freedom themselves.


2016 ◽  
Vol 94 (8) ◽  
Author(s):  
Antonio M. García-García ◽  
Bruno Loureiro ◽  
Aurelio Romero-Bermúdez

1998 ◽  
Vol 13 (16) ◽  
pp. 2739-2745 ◽  
Author(s):  
S. MUKAIGAWA ◽  
T. MUTA ◽  
S. D. ODINTSOV

A class of finite GUT's in curved space–time is considered in connection with the cosmological inflation scenario. It is confirmed that the use of the running scalar-gravitational coupling constant in these models helps realizing a successful chaotic inflation. The analyses are made for some different sets of the models.


Author(s):  
Stergios Pellis ◽  
Stergios Pellis Greece

In this paper are a new formula for the Planck length ℓpℓ and a new formula for the Avogadro number NA. Also 9 Mathematical formulas that connect dimensionless physical constants. The 6 dimensionless physical constants are the Proton to Electron Mass Ratio μ,the Fine-structure constant α,the ratio Ν1 of electric force to gravitational force between electron and proton,the Avogadro number NA,the Gravitational coupling constant αG for the electron and the gravitational coupling constant αG(p) of proton.


2019 ◽  
Vol 34 (13) ◽  
pp. 1950096 ◽  
Author(s):  
H. Moradpour ◽  
I. Licata ◽  
C. Corda ◽  
Ines G. Salako

Recently, a 4-index generalization of the Einstein theory has been proposed by Moulin [F. Moulin, Eur. Phys. J. C 77, 878 (2017)]. Using this method, we find the most general 2-index field equations derivable from the Einstein–Hilbert action. The application of Newtonian limit, the role of gravitational coupling constant and the effects of the properties of ordinary energy–momentum tensor in obtaining a 4-index gravity theory have been studied. We also address the results of building Weyl free 4-index gravity theory. Our study displays that both the Einstein and Rastall theories can be obtained as the subclasses of a 4-index gravity theory which shows the power of 4-index method in unifying various gravitational theories. It is also obtained that the violation of the energy–momentum conservation law may be allowed in 4-index gravity theory, and moreover, the contraction of 4-index theory generally admits a non-minimal coupling between geometry and matter field in the Rastall way. This study also shows that, unlike the Einstein case, the gravitational coupling constant of 4-index Rastall theory generally differs from that of the ordinary 2-index Rastall theory.


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