205 citations · 1.8k across the 41 of their papers we have counts for
41 papers
Cosmic variance and ergodicity in finite systems with correlations
Dipayan Mukherjee, Syksy Rasanen
We consider the difference between ensemble and volume average in cosmology. It is known that for sufficiently weak long-range correlations the root mean square of the difference,…
A covariant treatment of cosmic parallax
Syksy Rasanen
The Gaia satellite will soon probe parallax on cosmological distances. Using the covariant formalism and considering the angle between a pair of sources, we find parallax for both…
Violation of the FRW consistency condition as a signature of backreaction
Celine Boehm, Syksy Rasanen
We propose a backreaction toy model with realistic features and confront it with the Union2.1 supernova data. The model provides a good fit even though the expansion history is qui…
Vacuum energy and dynamical symmetry breaking in curved spacetime
Syksy Rasanen
We argue that calculating vacuum energy requires quantum field theory whose axioms are adapted to curved spacetime. In this context, we suggest that non-zero vacuum energy is conne…
Light propagation and the average expansion rate in near-FRW universes
Syksy Rasanen
We consider universes that are close to Friedmann-Robertson-Walker in the sense that metric perturbations, their time derivatives and first spatial derivatives are small, but secon…
Backreaction: directions of progress
Syksy Rasanen
Homogeneous and isotropic cosmological models with ordinary matter and gravity predict slower expansion and shorter distances than observed. It is possible that this failure is due…