Misaligned disks in binaries were commonly thought to evolve to
state. However, recent theory and observations have surprisingly
shown that disks around
eccentric orbit binaries can evolve to a polar state in which the
Galaxy clusters are the most massive gravitationally self-bound
objects in the Universe. These clusters form at the rare high peaks
of the primordial density fluctuations, and they subsequently trace
the growth of structure in the Universe as they...
Fast radio bursts (FRBs) are the brightest radio transients in
the universe. Since the unexpected discovery in the 21st century,
their extreme nature is one of the biggest mysteries of
astrophysics. FRBs are also unique probes of the universe...
One of the strongest predictions of the standard cold dark
matter paradigm is the hierarchy of structure down to Earth-mass
scales. However, individual self-bound clumps of dark
matter--"halos"--are difficult to detect directly. Instead,
Large-area surveys such as Gaia have given us an unprecedented
amount of data on stars in the Milky Way. One of the largest
ongoing challenges in understanding the present-day structure and
formation history of our Galaxy (i.e. Galactic archaeology)...
Astronomical observations indicate that coherent, dynamically
important magnetic fields are ubiquitous in the Universe. However,
neither the origin problem -- what are the physical mechanisms that
generate the initial ``seed'' magnetic fields —- nor...
Gravity plays the central role in structure formation and
evolution in astronomical scales. Despite the apparently simple
inverse square law for the gravitational force in the
non-relativistic regime, the dynamics of self-gravitating
I will describe the phenomenology of stellar basins: volumetric
stellar emission into gravitationally bound orbits of weakly
coupled particles such as axions, moduli, hidden photons, and
fermions. While only a tiny fraction of the instantaneous...
The Event Horizon Telescope (EHT) collaboration has recently
published the first image of the near-horizon region around the
supermassive black hole at the center of our Milky Way galaxy, Sgr
A*. In addition to providing new constraints on general...