The importance of binary stars

TL;DR

Binary stars are prevalent and crucial in understanding stellar evolution, interactions, and exotic phenomena, impacting various fields from astrophysics to gravity research.

Contribution

This paper summarizes the significance of binary stars in stellar evolution, interactions, and their role in producing exotic objects, highlighting their importance across multiple astrophysical domains.

Findings

Binary stars constitute at least 50% of solar-like stars.

Interactions in binary systems lead to exotic objects like gravitational wave progenitors.

Binary stars are essential for measuring stellar properties independently.

Abstract

Stars are mostly found in binary and multiple systems, as at least 50% of all solar-like stars have companions - a fraction that goes up to 100% for the most massive stars. Moreover, a large fraction of them will interact in some way or another over the course of their lives. Such interactions can, and often will, alter the structure and evolution of both components in the system. This will, in turn, lead to the production of exotic objects whose existence cannot be explained by standard single star evolution models, including gravitational wave progenitors, blue stragglers, symbiotic and barium stars, novae, and supernovae. More generally, binary stars prove crucial in many aspects, ranging from cultural ones, to constraining models of stellar evolution, star formation, and even, possibly, of gravity itself. They also provide a quasi-model independent way to determine stellar masses, radii, and luminosities. We here provide a brief summary of the importance of binary stars.