491 citations · 3.1k across the 187 of their papers we have counts for
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Scalar QED effective action in dS: implications for primordial magnetogenesis and the running of coupling constants
Ehsan Bavarsad, Sang Pyo Kim, Clément Stahl +1
Particles creation and vacuum polarization under the influence of both an electromagnetic field and a de~Sitter (dS) spacetime nonperturbatively probes quantum electrodynamics (QED…
Effect of Schwinger pair production on the evolution of the Hubble constant in de~Sitter spacetime
Ehsan Bavarsad, Sang Pyo Kim, Clément Stahl +1
In this proceeding we consider a massive charged scalar field in a uniform electric field background in a de~Sitter spacetime (dS). We compute the in-vacuum expectation value of th…
Effect of a magnetic field on Schwinger mechanism in de Sitter spacetime
Ehsan Bavarsad, Sang Pyo Kim, Clément Stahl +1
We investigate the effect of a constant magnetic field background on the scalar QED pair production in a four-dimensional de Sitter spacetime ($\dsf$). We have obtained the pair pr…
Schwinger effect and backreaction in de Sitter spacetime
Clément Stahl, She-Sheng Xue
We consider the particle-antiparticle pairs produced by both a strong electric field and de Sitter curvature. We investigate in 1 + 1 D the backreaction of the pairs on the electro…
Pair creation in the early universe
Clément Stahl, Eckhard Strobel, She-Sheng Xue
In the very early universe, a generalized Schwinger effect can create pairs from both electrical and gravitational fields. The expectation value of fermionic current induced by the…
Scalar current of created pairs by Schwinger mechanism in de Sitter spacetime
Ehsan Bavarsad, Clément Stahl, She-Sheng Xue
We consider a charged scalar field in a -dimensional de Sitter spacetime and investigate pair creation by a Schwinger mechanism in a constant electric field background. Using a…
Semiclassical pair production rate for rotating electric fields
Eckhard Strobel, She-Sheng Xue
We semiclassically investigate Schwinger pair production for pulsed rotating electric fields depending on time. To do so we solve the Dirac equation for two-component fields in a W…
Ultraviolet fixed point and massive composite particles in TeV scales
She-Sheng Xue
We present a further study of the dynamics of high-dimension fermion operators attributed to the theoretical inconsistency of the fundamental cutoff (quantum gravity) and the parit…
Semiclassical pair production rate for time-dependent electrical fields with more than one component: -WKB-approach and world-line instantons
Eckhard Strobel, She-Sheng Xue
We present an analytic calculation of the semiclassical electron-positron pair creation rate by time-dependent electrical fields. We use two methods, first the imaginary time metho…
Einstein-Euler-Heisenberg Theory and charged black holes
Remo Ruffini, Yuan-Bin Wu, She-Sheng Xue
Taking into account the Euler-Heisenberg effective Lagrangian of one-loop nonperturbative quantum electrodynamics (QED) contributions, we formulate the Einstein-Euler-Heisenberg th…
Fractional Effective Action at strong electromagnetic fields
Hagen Kleinert, Eckhard Strobel, She-Sheng Xue
In 1936, Weisskopf showed that for vanishing electric or magnetic fields the strong-field behavior of the one loop Euler-Heisenberg effective Lagrangian of quantum electro dynamics…
The phase and critical point of quantum Einstein-Cartan gravity
She-Sheng Xue
By introducing diffeomorphism and local Lorentz gauge invariant holonomy fields, we study in the recent article [S.-S. Xue, Phys. Rev. D82 (2010) 064039] the quantum Einstein-Carta…
Electron-positron pairs production in a macroscopic charged core
Remo Ruffini, She-Sheng Xue
Classical and semi-classical energy states of relativistic electrons bounded by a massive and charged core with the charge-mass-radio Q/M and macroscopic radius R_c are discussed.…
Detailed discussions and calculations of quantum Regge calculus of Einstein-Cartan theory
She-Sheng Xue
This article presents detailed discussions and calculations of the recent paper "Quantum Regge calculus of Einstein-Cartan theory" in Phys. Lett. B682 (2009) 300. The Euclidean spa…
Quantum Regge Calculus of Einstein-Cartan theory
She-Sheng Xue
We study the Quantum Regge Calculus of Einstein-Cartan theory to describe quantum dynamics of Euclidean space-time discretized as a 4-simplices complex. Tetrad field e_μ(x) and spi…
Electron-Positron Pair Production in Space- or Time-Dependent Electric Fields
Hagen Kleinert, Remo Ruffini, She-Sheng Xue
Treating the production of electron and positron pairs by a strong electric field from the vacuum as a quantum tunneling process we derive, in semiclassical approximation, a genera…
The phase structure of Einstein-Cartan theory
She-Sheng Xue
In the Einstein-Cartan theory of torsion-free gravity coupling to massless fermions, the four-fermion interaction is induced and its strength is a function of the gravitational and…
Effective Lagrangian of QED
Remo Ruffini, She-Sheng Xue
From the Euler-Heisenberg formula we calculate the exact real part of the one-loop effective Lagrangian of Quantum Electrodynamics in a constant electromagnetic field, and determin…
Gravitational instanton and cosmological term
She-Sheng Xue
Quantum fluctuation of unstable modes about gravitational instantons causes the instability of flat space at finite temperature, leading to the spontaneous process of nucleating qu…
Gravitational instanton, inflation and cosmological constant
She-Sheng Xue
Quantum fluctuation of unstable modes about gravitational instantons causes the instability of flat space at finite temperature, leading to the spontaneous process of nucleating qu…
On Quantum Radiation in Curved Spacetime
She-Sheng Xue
In the context of quantum field theories in curved spacetime, we compute the effective action of the transition amplitude from vacuum to vacuum in the presence of an external gravi…
Whether composite fermion states with ``wrong'' chiralities dissolve into cuts
She-Sheng Xue
In the possible scaling region for lattice chiral fermions advocated in hep-lat/9609037, no hard spontaneous symmetry breaking occurs and doublers are gauge-invariantly decoupled v…
On A Possible Ground State for Quantum Gravity
Giuliano Preparata, She-Sheng Xue
A variational calculation is presented of the ADM-energy of the quantized gravitational field around a wormhole solution of the classical Einstein's equations. One finds the energy…
On the Ground State of Quantum Gravity
S. Cacciatori, G. Preparata, S. Rovelli +2
In order to gain insight into the possible Ground State of Quantized Einstein's Gravity, we have devised a variational calculation of the energy of the quantum gravitational field…