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Gravitational instabilities in helicity-1 waves propagating through matter in equilibrium

Luis Bento·Jose P. S. Lemos
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Abstract

It is shown that the interaction of helicity-1 waves of gravity and matter in a thin slab configuration produces new types of instabilities. Indeed, a transverse spin-2 helicity-1 mode interacts strongly with the shear motion of matter. This mode is unstable above a critical wavelength which reminds the Jeans wavelength but with the speed of sound interchanged by the speed of light. The two instabilities are of course different. For the case analyzed, a plane parallel configuration, Jeans instability appears through a density wave perturbation, the material collapsing into a set of plane-parallel slabs. On the other hand, the helicity-1 wave instability induces a transverse motion in the fluid that tends to shear in the material along the node of the perturbation.

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Luis Bento, Jose P. S. Lemos. 2000-08-31. Gravitational instabilities in helicity-1 waves propagating through matter in equilibrium. https://doi.org/10.1088/0264-9381%2F17%2F18%2F102

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