Related papers: Apollo 11 and Fundamental Science
Highly accurate binary-pulsar timing plays an important role in test of General Relativity. In this Letter, we argue that PSR J0337+1715, a milli-second pulsar in a stellar triple system, could be a very good laboratory for testing the…
The Weak Equivalence Principle is the founding pillar of General Relativity and as such it should be verified as precisely as possible. The Microscope experiment tested it in low Earth orbit, finding that Pt and Ti test masses fall toward…
Lunar laser ranging has provided many of the best tests of gravitation since the first Apollo astronauts landed on the Moon. The march to higher precision continues to this day, now entering the millimeter regime, and promising continued…
Tests of the Weak Equivalence Principle (WEP) probe the foundations of physics. Ever since Galileo in the early 1600s, WEP tests have attracted some of the best experimentalists of any time. Progress has come in bursts, each stimulated by…
Three conceptually different masses appear in equations of motion for objects under gravity, namely, the inertial mass, $m_{\cal I}$, the passive gravitational mass, $m_{\cal P}$, and the active gravitational mass, $m_{\cal A}$. It is…
That gravitation can be understood as purely metric phenomenon depends crucially on the validity of a number of hypotheses which are summarised by the Einstein Equivalence Principle, the least well tested part of which being the…
The Equivalence Principle (EP) is not one of the ``universal'' principles of physics (like the Action Principle). It is a heuristic hypothesis which was introduced by Einstein in 1907, and used by him to construct his theory of General…
The Earth, Mars, Sun, Jupiter system allows for a sensitive test of the strong equivalence principle (SEP) which is qualitatively different from that provided by Lunar Laser Ranging. Using analytic and numerical methods we demonstrate that…
Newtonian gravity can be regarded as a hypothetic-deductive system where the inverse square law is the starting point from which gravitational phenomena are deduced. This operational form of presenting gravity endorses problem solving and…
The unprecedented precision of atom interferometry will soon lead to laboratory tests of general relativity to levels that will rival or exceed those reached by astrophysical observations. We propose such an experiment that will initially…
To date, no framework combining quantum field theory and general relativity and hence unifying all four fundamental interactions, exists. Violations of the Einstein's equivalence principle (EEP), being the foundation of general relativity,…
In his sixth problem, Hilbert called for an axiomatic approach to theoretical physics with an aim to achieve precision and rigour in scientific reasoning, where logic and language (semantics) of physics play the pivotal role. It is from…
The first direct experimental test of Einstein's theory of general relativity involved a pair of expeditions to measure the bending of light at a total solar eclipse that took place one hundred years ago, on 29 May 1919. So famous is this…
The perturbation of the lunar motion caused by a hypothetical violation of the equivalence principle is analytically worked out in terms of power series \`a la Hill-Brown. The interaction with the quadrupolar tide is found to amplify the…
Over the last few years, a set of new results from pulsar timing has introduced much tighter constraints on violations of the strong equivalence principle (SEP), either via a direct verification of the universality of free fall for a pulsar…
In this paper, we review tests of the strong equivalence principle (SEP) derived from pulsar-white dwarf data. The extreme difference in binding energy between both components and the precise measurement of the orbital motion provided by…
We consider the problem of testing the Einstein Equivalence Principle (EEP) by measuring the gravitational redshift with two Earth-orbiting stable atomic clocks. For a reasonably restricted class of orbits we find an optimal experiment…
The Weak Equivalence Principle (WEP), stating that two bodies of different compositions and/or mass fall at the same rate in a gravitational field (universality of free fall), is at the very foundation of General Relativity. The MICROSCOPE…
The only acceptable reason why measurements are irreversible and outcomes definite is the intrinsic definiteness and irreversibility of human sensory experience. While QBists deserve credit for their spirited defense of this position, Niels…
Most attempts to unify general relativity with the standard model of particle physics predict violations of the equivalence principle associated in some way with the composition of the test masses. We test this idea by using observational…