scholarly journals On the running electromagnetic coupling constant at $M_Z$

1999 ◽  
Vol 9 (4) ◽  
pp. 551-556 ◽  
Author(s):  
J.G. Körner ◽  
A.A. Pivovarov ◽  
K. Schilcher
Keyword(s):  
Electromagnetic Coupling ◽  
Coupling Constant

scholarly journals Thermodynamics of Charged Rotating Dilaton Black Branes Coupled to Logarithmic Nonlinear Electrodynamics

2016 ◽  
Vol 2016 ◽  
pp. 1-13 ◽  
Author(s):  
A. Sheykhi ◽  
M. H. Dehghani ◽  
M. Kord Zangeneh
Keyword(s):  
Thermal Stability ◽  
Electromagnetic Coupling ◽  
Nonlinear Electrodynamics ◽  
Black Brane ◽  
Dilaton Field ◽  
Coupling Constant ◽  
De Sitter ◽  
New Class ◽  
Unstable Phase ◽  
Complete Set

We construct a new class of charged rotating black brane solutions in the presence of logarithmic nonlinear electrodynamics with complete set of the rotation parameters in arbitrary dimensions. The topology of the horizon of these rotating black branes is flat, while due to the presence of the dilaton field the asymptotic behavior of them is neither flat nor (anti-)de Sitter [(A)dS]. We investigate the physical properties of the solutions. The mass and angular momentum of the spacetime are obtained by using the counterterm method inspired by AdS/CFT correspondence. We derive temperature, electric potential, and entropy associated with the horizon and check the validity of the first law of thermodynamics on the black brane horizon. We study thermal stability of the solutions in both canonical and grand-canonical ensemble and disclose the effects of the rotation parameter, nonlinearity of electrodynamics, and dilaton field on the thermal stability conditions. We find the solutions are thermally stable forα<1, while forα>1the solutions may encounter an unstable phase, whereαis dilaton-electromagnetic coupling constant.

NUMERICAL ANALYSIS OF GUTs PREDICTIONS IN THE LIGHT OF RECENT RESULTS FROM LEP

1992 ◽  
Vol 07 (35) ◽  
pp. 3319-3330
Author(s):  
DARIUSZ GRECH
Keyword(s):  
Z Boson ◽  
Electromagnetic Coupling ◽  
Boson Mass ◽  
Threshold Effects ◽  
Coupling Constant ◽  
Central Values ◽  
Unified Theories ◽  
Proton Lifetime ◽  
Experimental Values ◽  
Best Fit

We find numerical best fit for sin 2 Θw(MZ), unifying mass MX and the proton lifetime τp as the outcome of analysis where experimental values of Z boson mass MZ, strong coupling constant αs(MZ) and electromagnetic coupling α0(MZ) are taken as the only input parameters. It is found that simple nonsupersymmetric models are unlikely to be realistic ones. On the other hand, we find the best numerical fit: sin 2Θw(MZ = 0.2330 ± 0.0007 (theor.) ± 0.0027 (exp.) , [Formula: see text] yr for supersymmetric unified theories with three generations. The central values require, however, that the supersymmetric mass Λs≲300 GeV . Possibilities of increasing this limit as well as cases with four generations and threshold effects are also discussed. Compact formulas for theoretical and experimental uncertainties involved in the analysis are also produced.

High energy muon interactions - C.E.R.N. work on weak interactions

1965 ◽  
Vol 285 (1401) ◽  
pp. 248-256 ◽  
Keyword(s):  
Weak Interactions ◽  
Electromagnetic Coupling ◽  
High Energy ◽  
Nucleon Mass ◽  
Coupling Constant ◽  
Anomalous Effect ◽  
Intermediate Boson ◽  
High Energies ◽  
High Energy Muon ◽  
Made In

What I have to say will consist largely of speculation, because no unusual feature of muon interactions at high energies has yet been established. Considerable efforts have been made in the last few years to find an anomalous effect, but so far the result has been negative. This is probably because we have not yet reached high enough energies, as will become evident during the course of this talk. Figure 19 shows a number of possible interactions of the muon, which will be considered in detail below. There is first the electromagnetic coupling to the photon, with coupling constant e satisfying e 2 = 1/137 (figure 19( a )). Figure 19( b ) shows the weak interaction coupling, to the intermediate boson W ± (which is here assumed to exist). To obtain the correct strength for the overall weak four-fermion interaction one requires g 2 / m 2 w = G weak = 10 -5 / m 2 N , where m N is the nucleon mass. Thus only the ratio of g 2 to m 2 w is fixed.

On the running electromagnetic coupling constant at

1999 ◽  
Vol 9 (4) ◽  
pp. 551 ◽  
Author(s):  
J.G. Körner ◽  
A.A. Pivovarov ◽  
K. Schilcher
Keyword(s):  
Electromagnetic Coupling ◽  
Coupling Constant

scholarly journals FINITE T MESON CORRELATIONS AND QUARK DECONFINEMENT

2001 ◽  
Vol 16 (12) ◽  
pp. 2267-2291 ◽  
Author(s):  
D. BLASCHKE ◽  
G. BURAU ◽  
YU. L. KALINOVSKY ◽  
P. MARIS ◽  
P. C. TANDY
Keyword(s):  
Electromagnetic Coupling ◽  
Chiral Symmetry Breaking ◽  
Effective Interaction ◽  
Dominant Model ◽  
Finite Range ◽  
Coupling Constant ◽  
Quark Confinement ◽  
Separable Kernel ◽  
Quark Deconfinement ◽  
Three Space

The finite temperature spatial [Formula: see text] correlation modes in the π and ρ channels are studied with the rainbow-ladder truncated quark Dyson–Schwinger equation and Bethe–Salpeter equation in the Matsubara formalism. To retain the finite range of the effective interaction while facilitating summation over fermion Matsubara modes necessary to ensure continuity at T=0, a separable kernel is used. The model is fixed by T=0 properties and it implements dynamical chiral symmetry breaking and quark confinement. Transition temperatures for deconfinement (Td) and chiral restoration (Tc) are identified. Above and below these transitions we study Mπ(T), fπ(T) and the three-space transverse and longitudinal masses [Formula: see text] and [Formula: see text]. We also study the intrinsic T-dependence of the electromagnetic coupling constant gρ(T) and the strong coupling constant gρππ(T). For both this model and a related semi-analyticinfrared dominant model, we analyze the high T behavior of the obtained masses in comparison to the M(T)→2πT behavior found in lattice QCD simulations.

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