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Frédéric Moulin

Publications and source records attributed to Frédéric Moulin.

2 recordsLinked to original sources

n-dimensional Weyl conformal tensor in a 4-index gravitational field theory

The Weyl conformal tensor is the traceless component of the Riemann tensor and therefore, as is known, the information it contains does not appear explicitly in Einstein's equation. Following a rigorous mathematical treatment based on the variational principle, we will suggest that there exists a four-index gravitational field equation linearly containing the Weyl tensor closely related to a tidal gravitational field tensor whose components will be calculated. The new degrees of freedom, introduced via the n-dimensional Weyl tensor, will therefore clearly appear as additional constraints on the metric and we will demonstrate, among other things, that the cosmological constant appears as a natural solution of the four-index theory in the form of an integration constant which therefore does not need to be introduced ad hoc into a Lagrangian.

gr-qc↗

Generalization of Einstein's gravitational field equations

The Riemann tensor is the cornerstone of general relativity, but as everyone knows it does not appear explicitly in Einstein's equation of gravitation. This suggests that the latter may not be the most general equation. We propose here for the first time, following a rigorous mathematical treatment based on the variational principle, that there exists a generalized 4-index gravitational field equation containing the Riemann curvature tensor linearly, and thus the Weyl tensor as well. We show that this equation, written in $n$ dimensions, contains the energy-momentum tensor for matter and also that of the gravitational field itself. This new 4-index equation remains completely within the framework of general relativity and emerges as a natural generalization of the familiar 2-index Einstein equation. Due to the presence of the Weyl tensor, we show that this equation contains much more information, which fully justifies the use of a fourth-order theory.

physics.gen-ph↗