8 papers
Thermodynamic Cyclic Processes with Markov Samplers in Bayesian Inference
Heinrich von Campe, Bjoern Malte Schaefer
The concept of Markov chain Monte Carlo (MCMC) cycles, an analogy to cyclic processes in heat engines, is presented in order to examine Bayesian inference problems. In this effort,…
Visualisation of spherical harmonics in Peirce's quincuncial projection
Bjoern Malte Schaefer
The spherical harmonics are complex-valued functions on the surface of a sphere, and have found widespread application in physics and astronomy. Every physics stu…
Lagrangian neural ODEs: Measuring the existence of a Lagrangian with Helmholtz metrics
Luca Wolf, Tobias Buck, Bjoern Malte Schaefer
Neural ODEs are a widely used, powerful machine learning technique in particular for physics. However, not every solution is physical in that it is an Euler-Lagrange equation. We p…
On the full non-Gaussian Surprise statistic and the cosmological concordance between DESI, SDSS and Pantheon+
Pedro Riba Mello, Miguel Quartin, Bjoern Malte Schaefer +1
With the increasing precision of recent cosmological surveys and the discovery of important tensions within the CDM paradigm, it is becoming more and more important to develop t…
Bayesian distances for quantifying tensions in cosmological inference and the surprise statistic
Benedikt Schosser, Pedro Riba Mello, Miguel Quartin +1
Tensions between cosmological parameters derived through different channels can be a genuine signature of new physics that CDM as the standard model is not able to reproduce, in…
Friedmann-Robertson-Walker spacetimes from the perspective of geometric algebra
Pablo Banon Perez, Bjoern Malte Schaefer, Maarten DeKieviet
The intention of our paper is to provide a pedagogical application of geometric algebra to a particularly well-investigated system: We formulate the geometric and dynamical propert…
Constructing Exact Confidence Regions on Parameter Manifolds of Non-Linear Models
Rafael Arutjunjan, Bjoern Malte Schaefer, Clemens Kreutz
Using the mathematical framework of information geometry, we introduce a novel method which allows one to efficiently determine the exact shape of simultaneous confidence regions f…
Three-dimensional weak gravitational lensing of the 21-cm radiation background
Jose Agustin Lozano Torres, Bjoern Malte Schaefer
We study weak gravitational lensing by the cosmic large-scale structure of the 21-cm radiation background in the 3d-weak lensing formalism. The interplay between source distance me…