71 citations · 511 across the 22 of their papers we have counts for
22 papers
The variance of the CMB temperature gradient: a new signature of a multiply connected Universe
Ralf Aurich, Thomas Buchert, Martin J. France +1
In this work we investigate the standard deviation of the Cosmic Microwave Background (CMB) temperature gradient field as a signature for a multiply connected nature of the Univers…
Model-independent analyses of non-Gaussianity in Planck CMB maps using Minkowski Functionals
Thomas Buchert, Martin J. France, Frank Steiner
Despite the wealth of results, there are difficulties in disentangling the primordial non-Gaussianity of the Cosmic Microwave Background (CMB) from the secondary and the f…
Do Black Holes Exist in a Finite Universe Having the Topology of a Flat 3-Torus?
Frank Steiner
Based on perturbation theory, we present the exact first-order solution to the Einstein equations for the exterior static gravitational field of an isolated non-rotating star in a…
Zero modes of quantum graph Laplacians and an index theorem
Jens Bolte, Sebastian Egger, Frank Steiner
We study zero modes of Laplacians on compact and non-compact metric graphs with general self-adjoint vertex conditions. In the first part of the paper the number of zero modes is e…
An exact trace formula and zeta functions for an infinite quantum graph with a non-standard Weyl asymptotics
Sebastian Egger, Frank Steiner
We study a quantum Hamiltonian that is given by the (negative) Laplacian and an infinite chain of -like potentials with strength on the half line $\rz_{\geq0}$ and which i…
Ellipticity of Structures in CMB Sky Maps
Ralf Aurich, Holger S. Janzer, Sven Lustig +1
We study the ellipticity of contour lines in the sky maps of the cosmic microwave background (CMB) as well as other measures of elongation. The sensitivity of the elongation on the…