Related papers: Direct Observation Limits on Antimatter Gravitatio…
The gravitational force on antimatter has never been directly measured. A method is suggested for measuring the acceleration of antimatter $(\bar g)$ by measuring the deflection of a beam of neutral antihydrogen atoms in the Earth's…
Certain modern theories of gravity predict that antimatter will fall differently than matter in the Earth's gravitational field. However, no experimental tests of gravity on antimatter exist and all conclusions drawn from experiments on…
The GBAR experiment aims to directly test the Weak Equivalence Principle of ultracold antihydrogen in Earth's gravitational field. The gravitational acceleration $\bar{g}$ will be measured to a precision of $1\,\%$ using a classical free…
The production of antihydrogen by several research groups provides the opportunity to measure the gravitational behaviour of antimatter in the gravitational field of the Earth. The predictions in the literature range from normal attraction…
A number of experiments are currently underway on antimatter, particularly anti-hydrogen, to test whether the fundamental interactions behave the same way as for matter. Here we present a simple argument showing that a bound on a difference…
Measuring the effect of gravity on antimatter is a longstanding problem in physics that has significant implications for our understanding of the fundamental nature of the universe. Here, we present a technique to measure the gravitational…
The ALPHA collaboration recently published the article "Observation of the effects of gravity on the motion of antimatter" in issue 621 of Nature (2023), in which their conclusion states that "The probability that our data are consistent…
The ALPHA collaboration (of which I am a member) has made great strides recently in trapping antihydrogen and starting down the path of making spectroscopic measurements. The primary goal of the experiment is to test CPT invariance but…
In a paper by Villata (2011), the possibility of a repulsive gravitational interaction between antimatter and ordinary matter was discussed. The author argued that this anti-gravity can be regarded as a prediction of general relativity,…
The gravitational acceleration of antimatter, gbar, has yet to be directly measured; an unexpected outcome of its measurement could change our understanding of gravity, the universe, and the possibility of a fifth force. Three avenues are…
The AEgIS (Antimatter Experiment: Gravity, Interferometry, Spectroscopy) experiment, located at the Antimatter Factory at CERN, aims to study the asymmetry between matter and antimatter. In particular, its first goal is to measure the…
In light of recent experimental proposals to measure the free fall acceleration of antihydrogen in the earth's gravitational field, we investigate the bounds that existing experiments place on any asymmetry between the free fall of matter…
The gravitational acceleration of antimatter, $\bar g$, has yet to be directly measured but could change our understanding of gravity, the Universe, and the possibility of a fifth force. Three avenues are apparent for such a measurement:…
Different experiments are ongoing to measure the effect of gravity on cold neutral antimatter atoms such as positronium, muonium and antihydrogen. Among those, the project GBAR in CERN aims to measure precisely the gravitational fall of…
The gravitational acceleration of antimatter, $\bar{g}$, has never been directly measured and could bear importantly on our understanding of gravity, the possible existence of a fifth force, and the nature and early history of the universe.…
An equality of particle and antiparticle gravitational interactions holds in general relativity and is supported by indirect observations. Gravity dependence on rotation or spin direction is experimentally constrained for non-relativistic…
The universality of free fall, the weak equivalence principle (WEP), is a cornerstone of the general theory of relativity, the most precise theory of gravity confirmed in all experiments up to date. The WEP states the equivalence of the…
We present a theoretical study of the motion of the antihydrogen atom ($\bar{H}$) in the Earth's gravitational field above a material surface. We predict that $\bar{H}$ atom, falling in the Earth's gravitational field above a material…
We know that the generally accepted theories of gravity and quantum mechanics are fundamentally incompatible. Thus, when we try to combine these theories, we must beware of physical pitfalls. Modern theories of quantum gravity are trying to…
There has been renewed interest in the idea of antigravity -- that matter and antimatter repel gravitationally - in lieu of the recent beautiful ALPHA-g result for the free-fall acceleration of antihydrogen of $a_{\bar{H}}=(0.75\pm…