Claus Läemmerzahl

Frequency shifts due to relativistic effects and retardation in continuous-variable quantum key distribution

Emanuel Schlake, Jan P. Hackstein, Roy Barzel, Eva Hackmann et autres

Space-based quantum communication naturally involves satellites and ground stations exchanging optical signals at high altitudes and large relative velocities. Starting from general relativistic considerations, we systematically separate the frequency shift into longitudinal Doppler contributions, relativistic corrections, and corrections from the propagation delay …

de (code pays fourni par la source)

Quantum imaging as alternative readout in atom interferometry: The case of gravity

Marian Cepok, Dennis Rätzel, Claus Läemmerzahl

We propose a quantum imaging-inspired setup for measuring gravitational fields using an atom that emits a photon at one of two possible locations. The atom acquires a gravitationally induced quantum phase that it shares with the photon. By restoring the path identity …

de (code pays fourni par la source)

Massenbegriffe auf dem Prüfstand: Die drei Facetten der Masse

Eva Hackmann, Claus Läemmerzahl

Zusammenfassung Die Masse eines Körpers zeigt sich in drei konzeptionell unterschiedlichen Aspekten. Das schwache und das gravitative Äquivalenzprinzip besagen, dass diese drei Massen stets übereinstimmen. In diesem Artikel wurden sowohl die möglichen Konsequenzen einer Abweichung als auch die präzisesten Tests zur Überprüfung …

de (code pays fourni par la source)

Equilibrium models of Weyssenhoff spin fluid accretion tori around Kerr black holes

Sergio Gimeno-Soler, Sayantani Lahiri, Claus Läemmerzahl

The construction of equilibrium models of accretion disks around compact objects has become a highly relevant topic in the recent times, thanks to the current understanding that indicates a direct relationship between these objects with the electromagnetic emission of supermassive compact objects …

pt, de, us (code pays fourni par la source)

Gravitational Metrological Triangle

Claus Läemmerzahl, Sebastian Ulbricht

Motivated by the similarity of the mathematical structure of Einstein's general relativity in its weak field limit and of Maxwell's theory of electrodynamics it is shown that there are gravitational analogs of the Josephson effect and the quantum Hall effect. These effects …

de (code pays fourni par la source)

Thermodynamics of the Einstein-Euler-Heisenberg rotating black hole

Daniel Amaro, Nora Bretón, Claus Läemmerzahl, Alfredo Macı́as

We study the thermodynamic properties of a rotating electrically charged Einstein-Euler-Heisenberg black hole solution. This describes a QED generalization of the Kerr-Newman solution, which endows the vacuum with an effective dielectric constant. The QED-induced modifications to the thermodynamic quantities are presented and …

de, mx (code pays fourni par la source)

General Relativistic Chronometry from Ground and in Space

Dennis Philipp, Eva Hackmann, Jan P. Hackstein, Claus Läemmerzahl

Geodesy's primary objective lies in the determination of Earth's gravity field through ground and space-based measurements. General relativity and, thus, relativistic geodesy, introduce a novel perspective, leveraging high-precision clock comparisons to potentially unveil a new tool for globally determining Earth's gravito-electric potential …

de (code pays fourni par la source)

Potentials for general-relativistic geodesy

Claus Läemmerzahl, Volker Perlick

Geodesy in a Newtonian framework is based on the Newtonian gravitational potential. The general-relativistic gravitational field, however, is not fully determined by a single potential. The vacuum field around a stationary source can be decomposed into two scalar potentials and a tensorial …

Terrestrial Very-Long-Baseline Atom Interferometry: Workshop Summary

Sven Abend, Baptiste Allard, Iván Alonso, John Antoniadis et autres

This document presents a summary of the 2023 Terrestrial Very-Long-Baseline Atom Interferometry Workshop hosted by CERN. The workshop brought together experts from around the world to discuss the exciting developments in large-scale atom interferometer (AI) prototypes and their potential for detecting ultralight …

fr (code pays fourni par la source)

Stationary equilibrium torus supported by Weyssenhoff ideal spin fluid in Schwarzschild spacetime -- I: Case of constant specific angular momentum distribution

Sayantani Lahiri, Claus Läemmerzahl

We consider a non-self-gravitating geometrically thick torus described by Weyssenhoff ideal spin fluid in a black hole spacetime. The Weyssenhof spin fluid shares the same symmetries of the background geometry, i,e. stationarity and axisymmetry and further describes circular orbital motion in the …

Chronometry: On the redshift and relativistic gravity potential determination in GR

Dennis Philipp, Eva Hackmann, Claus Läemmerzahl

We derive exact expressions for the relativistic redshift and timing between observers in various configurations in stationary spacetimes for the purpose of chronometry, i.e., relativistic gravimetry based on clocks. These observers are assumed to be equipped with standard clocks and move along …

de (code pays fourni par la source)

Observer dependence of photon bunching: The influence of the relativistic redshift on Hong-Ou-Mandel interference

Roy Barzel, David Edward Bruschi, Andreas Wolfgang Schell, Claus Läemmerzahl

We study the influence of the relativistic redshift on Hong-Ou-Mandel (HOM) interference and present a genuine quantum test of general relativity. We use Glauber's theory of quantum coherence to predict the coincidence probability of realistic broadband photons in HOM experiments in a …

de (code pays fourni par la source)