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arXiv · 2507.03432

A covariant approach to the Dirac field in LRS space-times

Stefano Vignolo·Giuseppe De Maria·Luca Fabbri·Sante Carloni
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Abstract

We use the polar decomposition to describe the Dirac field in terms of an effective spinorial fluid. After reformulating all covariant equations in ``spinorial'' signature $(+ -- )$, we develop a $(1+1+2)$ covariant approach for the Dirac field that does not require the use of tetrad fields or Clifford matrices. By identifying the velocity and spin fields as the generators of time-like and space-like congruences, we examine the compatibility of a self-gravitating Dirac field with Locally Rotationally Symmetric space-times of types I, II, and III. We provide illustrative examples to demonstrate the effectiveness of our construction.

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Stefano Vignolo, Giuseppe De Maria, Luca Fabbri, Sante Carloni. 2025-07-04. A covariant approach to the Dirac field in LRS space-times. https://arxiv.org/abs/2507.03432

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