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Title: Scalar radiation with a quartic Galileon
The class of Galileon scalar fields theories encapsulate the Vainshtein screening mechanism, which is characteristic of a large range of infrared modified theories of gravity. Such theories can lead to testable departures from general relativity through fifth forces and new scalar modes of gravitational radiation. However, the inherent nonlinearity of the Vainshtein mechanism has limited analytic attempts to describe Galileon theories with both cubic and quartic interactions. To improve on this, we perform direct numerical simulations of the quartic Galileon model for a rotating binary source and infer the power spectrum of given multipoles. To tame numerical instabilities we utilize a low-pass filter, extending previous work on the cubic Galileon. Our findings show that the multipole expansion is well defined and under control. Moreover, our results confirm that despite being a nonlinear scalar, the dominant Galileon radiation is quadrupole, and we find a new scaling behavior deep inside the Vainshtein region. Published by the American Physical Society2024  more » « less
Award ID(s):
2309919
PAR ID:
10529024
Author(s) / Creator(s):
; ;
Publisher / Repository:
APS
Date Published:
Journal Name:
Physical Review D
Volume:
109
Issue:
10
ISSN:
2470-0010
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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