Speaker
Description
The binary zoo is well-known for its richness in exotic physics and for its expansive range of stellar properties. But what is it that we can test? There are many properties of matter related to stellar astrophysics that can be analyzed. For example, "gravity darkening" affects the surface brightness and depends on local surface gravity; this allows astronomers to test the theory of radiative transfer under extreme tidal and rotational distortion.
In this talk, I will primarily concentrate on the use of binaries to rule out or to highly constrain the validity of parameter space for alternative theories of gravity, such as MOND, Scalar-Tensor theories, Tensor-Vector-Scalar (TeVeS) theory amongst others. In particular, I will focus on the observed minimum orbital period of Cataclysmic Variables and show how this evidence strongly constrains any theory that predicts the production of copious amounts of dipolar gravitational radiation. Finally, I will review some of the very recent claims concerning the validity of the low-acceleration regime of MOND using observations of wide binaries, and I will discuss our own search for bona fide wide binaries (separation > 10,000 AU), and the possible implications for MOND.
