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Outputs (6)

Parametrized path approach to vacuum decay (2020)
Journal Article
Michel, F. (2020). Parametrized path approach to vacuum decay. Physical Review D, 101(4), Article 045021. https://doi.org/10.1103/physrevd.101.045021

We develop a new real-time approach to vacuum decay based on a reduction to a finite number of degrees of freedom. The dynamics is followed by solving a generalized Schrödinger equation. We first apply this method to a real scalar field in Minkowski... Read More about Parametrized path approach to vacuum decay.

Nonlinearities induced by parametric resonance in effectively 1D atomic Bose condensates (2018)
Journal Article
Robertson, S., Michel, F., & Parentani, R. (2018). Nonlinearities induced by parametric resonance in effectively 1D atomic Bose condensates. Physical Review D, 98(5), Article 056003. https://doi.org/10.1103/physrevd.98.056003

We present a numerical study of the dynamical effects following a sudden change of the transverse trapping frequency in an elongated Bose-Einstein condensate, which induces periodic oscillations of the radial density. At early times, we observe an ex... Read More about Nonlinearities induced by parametric resonance in effectively 1D atomic Bose condensates.

Relativistic collapse of axion stars (2018)
Journal Article
Michel, F., & Moss, I. G. (2018). Relativistic collapse of axion stars. Physics Letters B, 785, 9-13. https://doi.org/10.1016/j.physletb.2018.07.063

We study the gravitational collapse of axion dark matter in null coordinates, assuming spherical symmetry. Compared with previous studies, we use a simpler numerical scheme which can run, for relevant parameters, in a few minutes or less on a desktop... Read More about Relativistic collapse of axion stars.

Gravity waves on modulated flows downstream from an obstacle: The transcritical case (2018)
Journal Article
Michel, F., Parentani, R., & Robertson, S. (2018). Gravity waves on modulated flows downstream from an obstacle: The transcritical case. Physical Review D, 97(6), Article 065018. https://doi.org/10.1103/physrevd.97.065018

Periodic spatial modulations arise in analogue gravity experiments aimed at detecting the analogue version of the Hawking effect in a white-hole flow. Having the same spatial periodicity as low-frequency dispersive modes, they can induce resonances w... Read More about Gravity waves on modulated flows downstream from an obstacle: The transcritical case.

Excited cosmic strings with superconducting currents (2017)
Journal Article
Hartmann, B., Michel, F., & Peter, P. (2017). Excited cosmic strings with superconducting currents. Physical Review D, 96(12), Article 123531. https://doi.org/10.1103/physrevd.96.123531

We present a detailed analysis of excited cosmic string solutions that possess superconducting currents. These currents can be excited inside the string core, and—if the condensate is large enough—can lead to the excitations of the Higgs field. Next... Read More about Excited cosmic strings with superconducting currents.

Assessing degrees of entanglement of phonon states in atomic Bose gases through the measurement of commuting observables (2017)
Journal Article
Robertson, S., Michel, F., & Parentani, R. (2017). Assessing degrees of entanglement of phonon states in atomic Bose gases through the measurement of commuting observables. Physical Review D, 96(4), Article 045012. https://doi.org/10.1103/physrevd.96.045012

We show that measuring commuting observables can be sufficient to assess that a bipartite state is entangled according to either nonseparability or the stronger criterion of “steerability.” Indeed, the measurement of a single observable might reveal... Read More about Assessing degrees of entanglement of phonon states in atomic Bose gases through the measurement of commuting observables.