204 citations · 1.6k across the 66 of their papers we have counts for
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A simple property of the Weyl tensor for a shear, vorticity and acceleration-free velocity field
Luca Guido Molinari, Carlo Alberto Mantica
We prove that, in a space-time of dimension n>3 with a velocity field that is shear-free, vorticity-free and acceleration-free, the covariant divergence of the Weyl tensor is zero…
Notes on Wick's theorem in many-body theory
Luca Guido Molinari
In this pedagogical note I present the operator form of Wick's theorem, i.e. a procedure to bring a product of 1-particle creation and destruction operators to normal order, with r…
Simple conformally recurrent space-times are conformally recurrent PP-waves
Carlo Alberto Mantica, Luca Guido Molinari
We show that in dimension n>3 the class of simple conformally recurrent space-times coincides with the class of conformally recurrent pp-waves.
Generalized Robertson-Walker space times, a survey
Carlo Alberto Mantica, Luca Guido Molinari
Generalized Robertson-Walker spacetimes extend the notion of Robertson-Walker spacetimes, by allowing for spatial non-homogeneity. A survey is presented, with main focus on Chen's…
On the Weyl and Ricci tensors of Generalized Robertson-Walker space-times
Carlo Alberto Mantica, Luca Guido Molinari
We prove theorems about the Ricci and the Weyl tensors on generalized Robertson-Walker space-times of dimension . In particular, we show that the concircular vector introdu…
Random Antagonistic Matrices
Giovanni M. Cicuta, Luca Guido Molinari
The ensemble of antagonistic matrices is introduced and studied. In antagonistic matrices the entries and are real and have opposite signs, or…