Gravitational redshift test of EEP with RadioAstron from near Earth to the distance of the Moon

The Einstein Equivalence Principle (EEP) is a cornerstone of general relativity and predicts the existence of gravitational redshift. We report on new results of measuring this shift with RadioAstron (RA), a space very long baseline interferometry (VLBI) spacecraft launched into an evolving high eccentricity orbit around Earth with geocentric...

The Influence of Dynamic Solar Oblateness on Tracking Data Analysis from Past and Future Mercury Missions

When the BepiColombo spacecraft arrives at Mercury in late 2025, it will be able to measure the orbit of the planet with unprecedented accuracy, allowing for more accurate measurements of the perihelion advance of the planet, as predicted by the Theory of General Relativity (GR). A similar effect is produced by the gravitational oblateness of...

Result of the MICROSCOPE weak equivalence principle test

The space mission MICROSCOPE dedicated to the test of the equivalence principle (EP) operated from April 25, 2016 until the deactivation of the satellite on October 16, 2018. In this analysis we compare the free-fall accelerations (a _A and a _B) of two test masses in terms of the Eötvös parameter η ( A,B ) = 2 a A − a B a...

The influence of a dynamic solar shape on tests of gravitational theory using observations of Mercury missions

Tests of General Relativity are often done in the Solar System by using tracking data from interplanetary space missions, to measure the perturbation on the orbits of the planets that is predicted by General Relativity. The next best opportunity for such a test is the BepiColombo spacecraft by the European Space Agency, which will arrive at...

On Covariant Emergent Gravity

This Bachelor thesis is on Covariant Emergent Gravity (CEG): a covariant formulation by Sabine Hossenfelder of the ideas of Erik Verlinde on gravity as an emergent force. In this work, the ideas of Erik Verlinde are presented as well as the field equations of CEG. The aim of this thesis is to find experimentally verifiable results for CEG. From...

Simulation of RadioAstron Gravitational Redshift Experiment Accuracy

Einstein Gravity Explorer–a medium-class fundamental physics mission

The Einstein Gravity Explorer mission (EGE) is devoted to a precise measurement of the properties of space-time using atomic clocks. It tests one of the most fundamental predictions of Einstein’s Theory of General Relativity, the gravitational redshift, and thereby searches for hints of quantum effects in gravity, exploring one of the most...