Astrophysics with the Laser Interferometer Space Antenna

TL;DR

LISA will revolutionize gravitational wave astronomy by enabling multi-messenger observations and advancing understanding of key astrophysical sources like black hole binaries and stellar systems through improved modeling and analysis techniques.

Contribution

This review synthesizes current knowledge and highlights open issues in modeling LISA's primary astrophysical sources, proposing new research directions and data analysis improvements.

Findings

LISA will provide unique insights into black hole and stellar systems.

Modeling techniques are evolving with numerical simulations and data science.

Open issues remain in understanding source populations and astrophysical processes.

Abstract

The Laser Interferometer Space Antenna (LISA) will be a transformative experiment for gravitational wave astronomy, and, as such, it will offer unique opportunities to address many key astrophysical questions in a completely novel way. The synergy with ground-based and space-born instruments in the electromagnetic domain, by enabling multi-messenger observations, will add further to the discovery potential of LISA. The next decade is crucial to prepare the astrophysical community for LISA's first observations. This review outlines the extensive landscape of astrophysical theory, numerical simulations, and astronomical observations that are instrumental for modeling and interpreting the upcoming LISA datastream. To this aim, the current knowledge in three main source classes for LISA is reviewed; ultracompact stellar-mass binaries, massive black hole binaries, and extreme or intermediate mass ratio inspirals. The relevant astrophysical processes and the established modeling techniques are summarized. Likewise, open issues and gaps in our understanding of these sources are highlighted, along with an indication of how LISA could help making progress in the different areas. New research avenues that LISA itself, or its joint exploitation with upcoming studies in the electromagnetic domain, will enable, are also illustrated. Improvements in modeling and analysis approaches, such as the combination of numerical simulations and modern data science techniques, are discussed. This review is intended to be a starting point for using LISA as a new discovery tool for understanding our Universe.