  <PART1> According to the standard LCDM model, the matter and dark energy
densities (rho_m and rho_DE) are only comparable for a brief time. We address
the cosmic coincidence problem under LCDM and generalized dark energy models by
considering the temporal distribution of terrestrial planets. <PART2> We
compare the Sun to representative stellar samples in 11 properties plausibly
related to life. We find the Sun to be most anomalous in mass and galactic
orbital eccentricity. When the 11 properties are considered together, the
observed "anomalies" are consistent with statistical noise. This contrasts with
previous work suggesting anthropic explanations for the Sun's high mass.
<PART3> The long-term future of dissipative processes (such as life) depends on
the continued ability to use free energy to increase the total entropy. The
entropy budget of the present observable Universe is dominated by supermassive
black holes in galactic cores. We report a new entropy budget of the Universe
with quantified uncertainties for all components. We find the total entropy in
the observable Universe to be S_{obs} = 3.1^{+3.0}_{-1.7} x 10^{104} k, at
least an order of magnitude higher than previous estimates due to improved
measurements of the mass function of supermassive black holes (which dominate
the budget). We evaluate upper bounds on the entropy of a comoving volume.
Under the assumption that energy in matter is constant in a comoving volume,
the availability of free energy is found to be finite and the future entropy in
the volume is limited to a constant of order 10^{123} k. Through this work we
uncover a number of unresolved questions with implications for the ultimate
fate of the Universe.
