20 citations · 39 across the 6 of their papers we have counts for
6 papers
Interacting Kerr-Newman Electromagnetic Fields
Sajad Aghapour, Lars Andersson, Kjell Rosquist +1
In this paper, we study some of the properties of the limit of the Kerr-Newman solution of Einstein-Maxwell equations. Noting Carter's observation of the near equality be…
Helicity, Spin, and Infra-zilch of Light: a Lorentz Covariant Formulation
Sajad Aghapour, Lars Andersson, Kjell Rosquist
In this paper, a novel conserved Lorentz covariant tensor, termed the helicity tensor, is introduced in Maxwell theory. The conservation of the helicity tensor expresses the conser…
The Zilch Electromagnetic Conservation Law Revisited
Sajad Aghapour, Lars Andersson, Kjell Rosquist
It is shown that the zilch conservation law arises as the Noether current corresponding to a variational symmetry of a duality-symmetric Maxwell Lagrangian. The action of the corre…
Helicity and spin conservation in Maxwell theory and Linearized Gravity
Sajad Aghapour, Lars Andersson, Reebhu Bhattacharyya
A duality symmetric formulation of linearized gravity has been introduced by Barnett and used to show the conservation of helicity. However, the relation between helicity and spin…
On variational principle and canonical structure of gravitational theory in double-foliation formalism
Sajad Aghapour, Ghadir Jafari, Mehdi Golshani
In this paper, we analyze the variation of the gravitational action on a bounded region of spacetime whose boundary contains segments with various characters, including null. We de…
Black Hole Entropy from Entropy of Hawking Radiation
Sajad Aghapour, Kamal Hajian
We provide a simple way for calculating the entropy of a Schwarzschild black hole from the entropy of its Hawking radiation. To this end, we show that if a thermodynamic system los…