24 citations · 46 across the 9 of their papers we have counts for
9 papers
Counterexamples to the Lorentzian Calderón problem
Lauri Oksanen, Miika Sarkkinen
We show that two non-isometric, smooth, globally hyperbolic Lorentzian metrics can have the same hyperbolic Dirichlet-to-Neumann map on an infinite cylinder with timelike boundary.
Recovery of a matrix valued potential for the wave equation on stationary spacetimes
Spyridon Filippas, Lauri Oksanen, Miika Sarkkinen
We study the problem of recovering a time dependent matrix valued potential on a globally hyperbolic manifold from the knowledge of the source to solution map of a wave equation in…
Bulk metric reconstruction from entanglement data via minimal surface area variations
Niko Jokela, Tony Liimatainen, Miika Sarkkinen +1
We investigate the reconstruction of asymptotically anti-de Sitter (AdS) bulk geometries from boundary entanglement entropy data for ball-shaped entangling regions. By deriving an…
On the interplay between the light ray and the magnetic X-ray transforms
Lauri Oksanen, Gabriel P. Paternain, Miika Sarkkinen
We study the light ray transform acting on tensors on a stationary Lorentzian manifold. Our main result is injectivity up to the natural obstruction as long as the associated magne…
Inflationary gravitational wave background as a tail effect
Niko Jokela, K. Kajantie, M. Laine +2
The free propagator of a massless mode in an expanding universe can be written as a sum of two terms, a lightcone and a tail part. The latter describes a subluminal (time-like) sig…
Gravitational wave memory in conformally flat spacetimes
Niko Jokela, K. Kajantie, Miika Sarkkinen
We study the gravitational wave memory effect in spacetimes related to flat space by a conformal transformation. The discussion is general but the gravitational wave length scale i…
Gravitational wave memory and its tail in cosmology
Niko Jokela, K. Kajantie, Miika Sarkkinen
We study gravitational wave memory effect in the FRW cosmological model with matter and cosmological constant. Since the background is curved, gravitational radiation develops a ta…
Memory effect in Yang-Mills theory with an axion
Niko Jokela, K. Kajantie, Miika Sarkkinen
We study the empirical realization of the memory effect in Yang-Mills theory with an axion-like particle, especially in view of the classical vs. quantum nature of the theory. We s…
Memory effect in Yang-Mills theory
Niko Jokela, K. Kajantie, Miika Sarkkinen
We study the empirical realisation of the memory effect in Yang-Mills theory, especially in view of the classical vs. quantum nature of the theory. Gauge invariant analysis of memo…