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Introduction to Quantum Effects in Gravity
This book, first published in 2007, is an introductory textbook on quantum field theory in gravitational backgrounds intended for undergraduate and beginning graduate students in the fields of
Probabilities in the inflationary multiverse
Inflationary cosmology leads to the picture of a 'multiverse', involving an infinite number of (spatially infinite) post-inflationary thermalized regions, called pocket universes. In the context of
Uniform Approximations for Transcendental Functions
A heuristic method to construct uniform approximations to analytic transcendental functions is developed as a generalization of the Hermite-Pade interpolation to infinite intervals and in one case (Lambert's W function) the authors obtained a uniform approximation valid in the entire complex plane.
Probability distribution for omega in open universe inflation
The problem of making predictions in eternally inflating universe that thermalizes by bubble nucleation is considered. A recently introduced regularization procedure is applied to find the
Effective noise in stochastic description of inflation
Stochastic description of inflationary spacetimes emulates the growth of vacuum fluctuations by an effective stochastic ``noise field'' which drives the dynamics of the volume-smoothed inflaton. We
Null energy condition violations in eternal inflation
The usual scenario of ``eternal inflation'' involves an approximately de Sitter spacetime undergoing upward fluctuations of the local expansion rate $H$. This spacetime requires frequent violations
Computing the Incomplete Gamma Function to Arbitrary Precision
  • S. Winitzki
  • Mathematics, Computer Science
  • 18 May 2003
It is shown that the incomplete Gamma function Γ (a, z) can be computed to P digits in at most O(P) long multiplications uniformly in z for Re z > 0.
Cosmological particle production and the precision of the WKB approximation
Particle production by slow-changing gravitational fields is usually described using quantum field theory in curved spacetime. Calculations require a definition of the vacuum state, which can be
Signatures of kinetic and magnetic helicity in the cosmic microwave background radiation
$P$ and $\mathrm{CP}$ violation in cosmology can be manifested as large-scale helical velocity flows in the ambient plasma and as primordial helical magnetic fields. We show that kinetic helicity at