Sergiu Klainerman’s scientific contributions

... ♦ thomas.mieling@univie.ac.at ♥ marius.oancea@univie.ac.at ♠ elisabeth.steininger@univie.ac.at and the final separations of pairs of freely falling test particles can differ due to the resulting gravitational waves. Going beyond the weak-field approximation, a nonlinear memory effect was later obtained by Christodoulou [3] based on mathematical methods used in the proof of the stability of Minkowski spacetime [4,5]. This has as its physical origin the flux of effective stress-energy which is associated with the gravitational waves emitted by a compact system [6,7]. ...

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Gravitational wave memory and its effects on particles and fields

... Lately, improvements [22,23] to the extraction of gravitational waves to future null infinity from numerical relativity simulations have made it possible to capture memory effects in BBHs, extending previous analytic and semi-analytical results [24][25][26][27][28] to a fully non-perturbative regime. These effects are associated with a net change in the structure of spacetime after the passage of a burst of gravitational radiation. ...

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Modeling the BMS transformation induced by a binary black hole merger