How to Delay Death and Look Further Into the Future if You Fall Into a Black Hole

Resonance

article

Alexei Toporensky¹  Sergei Popov¹ 

[1] Sternberg Astronomical Institute Universitetski pr. 13 Moscow

关键词: General relativity;    black holes;    Lemaitre frame;    free fall.;   

DOI  :  10.1007/s12045-023-1602-8

学科分类：社会科学、人文和艺术（综合）

来源: Springer

【 摘 要 】

In this note, we present a pedagogical illustration of peculiar properties of motion in the vicinity of and inside black holes. We discuss how a momentary impulse can modify the life­time of an object radially falling into a Schwarzschild black hole down to singularity. The well-known upper limit for a proper time spent within a horizon, in fact, requires an in­finitely powerful kick. We calculate the proper time interval (perceived as the personal lifetime of a falling observer) till the contact with the singularity, as well as the time interval in the Lemaitre frame (which reflects how far into the future of the outer world a falling observer can look), for different values of the kick received by the falling body. We discuss the ideal strategy to increase both time intervals by an engine with a finite power. This example is suitable for university seminars for undergraduate students specializing in general relativity and related astrophysical subjects.

【 授权许可】

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