arXiv subjects

H. Babaei-Aghbolagh

Publications and source records attributed to H. Babaei-Aghbolagh.

23 records · Page 2Linked to original sources

arXiv2021

Holographic complexity for black branes with momentum relaxation

We employ the "complexity equals action" conjecture to investigate the action growth rate for the charged and neutral AdS black branes of a holographic toy model consisting of Einstein-Maxwell theory in $d + 1$-dimensional bulk spacetime with $d - 1$ massless scalar fields which is called Einstein-Maxwell-Axion (EMA) theory. From the holographic point of view, the scalar fields source a spatially dependent field theory with momentum relaxation on the boundary, which is dual to the homogeneous and isotropic black branes. We find that the growth rate of the holographic complexity within the Wheeler-DeWitt (WDW) patch saturates the corresponding Lloyd's bound at the late time limit. Especially for the neutral AdS black branes, it will be shown that the complexity growth rate at late time vanishes for a particular value of relaxation parameter $β_{max}$ where the temperature of the black hole is minimal. Then, we investigate the transport properties of the holographic dual theory in the minimum temperature. A non-linear contribution of the axion field kinetic term in the context of k-essence model in the four-dimensional spacetime is considered as well. We also study the time evolution of the holographic complexity for the dyonic AdS black branes in this model.

hep-th↗

arXiv2021

$T\bar{T}$-like Flows in Non-linear Electrodynamic Theories and S-duality

We investigate the $T\bar{T}$-like flows for non-linear electrodynamic theories in $D(=\!\!2n)$-dimensional spacetime. Our analysis is restricted to the deformation problem of the classical free action by employing the proposed $T\bar{T}$ operator from a simple integration technique. We show that this flow equation is compatible with $T\bar{T}$ deformation of a scalar field theory in $D\!=\!2$ and of a non-linear Born-Infeld type theory in $D\!=\!4$ dimensions. However, our computation discloses that this kind of $T\bar{T}$ flow in higher dimensions is essentially different from deformation that has been derived from the AdS/CFT interpretations. Indeed, the gravity that may be exist as a holographic dual theory of this kind of effective Born-Infeld action is not necessarily an AdS space. As an illustrative investigation in $D\!=\!4$, we shall also show that our construction for the $T\bar{T}$ operator preserves the original $SL(2,R)$ symmetry of a non-supersymmetric Born-Infeld theory, as well as $\mathcal{N}=2$ supersymmetric model. It is shown that the corresponding $SL(2,R)$ invariant action fixes the relationship between the $T\bar{T}$ operator and quadratic form of the energy-momentum tensor in $D\!=\!4$.

hep-th↗

arXiv2019

S-dual Amplitude and D3-Brane Couplings

Recently, it has been observed that the IIB scattering amplitudes are compatible with the standard rules of S-duality. Inspired by this observation, we will find the tree-level S-matrix elements of one Ramond-Ramond and three open strings by imposing this symmetry on the tree-level S-matrix elements of one Kalb-Ramond and three open strings. We also find a SL(2, R) invariant form of the D3-brane effective action containing four gauge fields with derivative corrections that was derived from one-loop level four-point amplitude. Using the expansion of the nonlinear SL(2, R) invariant structures, we find the action with derivative corrections at the level of more gauge fields

hep-th↗

arXiv2016

On SL(2;R) symmetry in nonlinear electrodynamics theories

Recently, it has been observed that the Noether-Gaillard-Zumino (NGZ) identity holds order by order in $α'$ expansion in nonlinear electrodynamics theories as Born-Infeld (BI) and Bossard-Nicolai (BN). The nonlinear electrodynamics theory that couples to an axion field is invariant under the $SL(2,R)$ duality in all orders of $α'$ expansion in the Einstein frame. In this paper we show that there are the $SL(2,R)$ invariant forms of the energy momentum tensors of axion-nonlinear electrodynamics theories in the Einstein frame. These $SL(2,R)$ invariant structures appear in the energy momentum tensors of BI and BN theories at all orders of $α'$ expansion. The $SL(2,R)$ symmetry appears in the BI and BN Lagrangians as a multiplication of Maxwell Lagrangian and a series of $SL(2,R)$ invariant structures.

hep-th↗

arXiv2013

S-duality of tree-level S-matrix elements in D$_3$-brane effective action

Recently it has been speculated that the S-matrix elements on the world volume of D$_3$-branes should satisfy the ward identity corresponding to the S-duality transformations. For a single brane and in the low energy limit, this indicates that in the abelian Dirac-Born-Indeld-Chern-Simons theory the combination of contact terms and tree-level massless poles in an $n$-point function should satisfy the S-duality. In this paper we examine in details the S-matrix element of three gauge bosons and one two-form and the S-matrix element of six gauge bosons in favor of the above proposal.

hep-th↗