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Modelling general relativistic perfect fluids in field theoretic language

Nikolai V. Mitskievich
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Abstract

Skew-symmetric massless fields, their potentials being $r$-forms, are close analogues of Maxwell's field (though the non-linear cases also should be considered). We observe that only two of them ($r=$2 and 3) automatically yield stress-energy tensors characteristic to normal perfect fluids. It is shown that they naturally describe both non-rotating ($r=2$) and rotating (then a combination of $r=2$ and $r=3$ fields is indispensable) general relativistic perfect fluids possessing every type of equations of state. Meanwile, a free $r=3$ field is completely equivalent to appearance of the cosmological term in Einstein's equations. Sound waves represent perturbations propagating on the background of the $r=2$ field. Some exotic properties of these two fields are outlined.

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Nikolai V. Mitskievich. 1998-11-23. Modelling general relativistic perfect fluids in field theoretic language. https://arxiv.org/abs/gr-qc/9811077

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