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High-Speed Cylindrical Collapse of Perfect Fluid

Ken-ichi Nakao·Yoshiyuki Morisawa
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Abstract

The gravitational collapse of cylindrically distributed perfect fluid is studied. We assume the collapsing speed of fluid is very large and investigate such a situation by recently proposed high-speed approximation scheme. We show that if the value of the pressure divided by the energy density is bounded below by some positive value, the high-speed collapse is necessarily halted. This suggests that the collapsing perfect fluid of realistic ideal gas experiences the pressure bounce. However even in the case of mono-atomic ideal gas, arbitrarily large tidal force for freely falling observers are realizable by setting the initial collapsing velocity exceedingly large. In order that the high-speed collapse of cylindrical perfect fluid forms spacetime singularity, the equation of state should be very soft.

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Ken-ichi Nakao, Yoshiyuki Morisawa. 2005-02-04. High-Speed Cylindrical Collapse of Perfect Fluid. https://doi.org/10.1143/ptp.113.73

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