True dynamical tests of the weak equivalence principle for matter and anti-matter

2014 ◽  
Vol 30 ◽  
pp. 1460267 ◽  
Author(s):  
C. S. Unnikrishnan
Keyword(s):  
Equivalence Principle ◽  
Practical Importance ◽  
Weak Equivalence ◽  
Intrinsic Properties ◽  
General Belief ◽  
Weak Equivalence Principle ◽  
Quantum Numbers ◽  
Remarkable Result ◽  
Relativistic Kinetic Energy ◽  
The Universe

After a brief review of the evidence for the validity of the Weak Equivalence principle for anti-matter, I show that, contrary to general belief, the near equality of the Shapiro delay for photons, neutrinos and anti-neutrinos in the galactic gravitational potential is not a true test of the WEP for their intrinsic properties and quantum numbers due to the overwhelming contribution to the gravitational mass from the relativistic kinetic energy. Then I prove the remarkable result that particles that obey the Newtonian law of dynamics automatically respect the WEP due to the firm equivalence between the law of motion and the WEP in any relativistic scenario, through gravity of all the matter in the Universe. Thus a test of the validity of Newtons's law in any force field is a true test of the WEP and provides strong direct tests of WEP for anti-particles. This result opens up an entire new insight of conceptual and practical importance for the tests of WEP.

FALLING RIGHT WHILE MOVING SLOW: TRUE TESTS OF THE WEAK EQUIVALENCE PRINCIPLE FOR ANTIPARTICLES

2012 ◽  
Vol 21 (11) ◽  
pp. 1242016
Author(s):  
C. S. UNNIKRISHNAN ◽  
G. T. GILLIES
Keyword(s):  
Equivalence Principle ◽  
Free Fall ◽  
Weak Equivalence ◽  
Surprising Result ◽  
Intrinsic Properties ◽  
Weak Equivalence Principle ◽  
Quantum Numbers ◽  
Supernova 1987A ◽  
Relativistic Factor ◽  
Cold Matter

A significant question in experimental gravity is the nature of free fall of antiparticles under gravity and elaborate preparations are underway to directly test this with cold antihydrogen. Earlier, the Shapiro delay of supernova 1987A neutrinos was interpreted as testing the weak equivalence principle (WEP). We establish the surprising result that the Shapiro delay of relativistic particles does not test WEP for intrinsic properties or quantum numbers of particles or antiparticles. This is because essentially the entire gravitational mass of the relativistic neutrinos is contributed by kinetic energy, diluting to insignificance any EP violating contribution from intrinsic properties, by the relativistic factor. The crucial message here is that a true test of the WEP involving intrinsic properties of matter or antimatter — the foundation of relativistic gravity — necessarily requires nonrelativistic "cold" matter and antimatter.

scholarly journals Gravitational coupling and the cosmological constant

2018 ◽  
Vol 27 (08) ◽  
pp. 1850086
Author(s):  
Yousef Bisabr
Keyword(s):  
Cosmological Constant ◽  
Equivalence Principle ◽  
Weak Equivalence ◽  
Gravitational Coupling ◽  
Dynamical Mechanism ◽  
Metric Tensor ◽  
Weak Equivalence Principle ◽  
Gravitational Model ◽  
Expansion Of The Universe ◽  
The Universe

We deal with a dynamical mechanism in which a large cosmological constant, as suggested by inflationary scenarios, decays due to expansion of the universe. This mechanism has its origin in the gravitational coupling of the vacuum density. We assume that the vacuum couples anomalously to gravity that is the metric tensor that appears the gravitational part is not the same as that appears the matter part as suggested by weak equivalence principle. Instead, the two metric tensors are taken to be conformally related. We show that this provides a dynamical mechanism which works during expansion of the universe. We also consider some observational consequences of such a gravitational model.

scholarly journals Testing the weak equivalence principle

2009 ◽  
Vol 5 (S261) ◽  
pp. 390-401 ◽  
Author(s):  
Anna M. Nobili ◽  
Gian Luca Comandi ◽  
Raffaello Pegna ◽  
Donato Bramanti ◽  
Suresh Doravari ◽  
...  
Keyword(s):  
General Relativity ◽  
Equivalence Principle ◽  
Large Scale ◽  
Past History ◽  
Low Earth Orbit ◽  
Small Scale ◽  
Current View ◽  
Weak Equivalence ◽  
Weak Equivalence Principle ◽  
The Universe

AbstractThe discovery of Dark Energy and the fact that only about 5% of the mass of the universe can be explained on the basis of the current laws of physics have led to a serious impasse. Based on past history, physics might indeed be on the verge of major discoveries; but the challenge is enormous. The way to tackle it is twofold. On one side, scientists try to perform large scale direct observations and measurements – mostly from space. On the other, they multiply their efforts to put to the most stringent tests ever the physical theories underlying the current view of the physical world, from the very small to the very large. On the extremely small scale very exciting results are expected from one of the most impressive experiments in the history of mankind: the Large Hadron Collider. On the very large scale, the universe is dominated by gravity and the present impasse undoubtedly calls for more powerful tests of General Relativity – the best theory of gravity to date. Experiments testing the Weak Equivalence Principle, on which General Relativity ultimately lies, have the strongest probing power of them all; a breakthrough in sensitivity is possible with the “Galileo Galilei” (GG) satellite experiment to fly in low Earth orbit.

scholarly journals Testing the Weak Equivalence Principle Using Optical and Near-infrared Crab Pulses

2018 ◽  
Vol 861 (1) ◽  
pp. 66 ◽  
Author(s):  
Calvin Leung ◽  
Beili Hu ◽  
Sophia Harris ◽  
Amy Brown ◽  
Jason Gallicchio ◽  
...  
Keyword(s):  
Equivalence Principle ◽  
Near Infrared ◽  
Weak Equivalence ◽  
Weak Equivalence Principle

scholarly journals Tests of weak equivalence principle with the gravitational wave signals in the LIGO–Virgo catalogue GWTC-1

2020 ◽  
Vol 499 (1) ◽  
pp. L53-L57
Author(s):  
Shu-Cheng Yang ◽  
Wen-Biao Han ◽  
Gang Wang
Keyword(s):  
Gravitational Wave ◽  
Equivalence Principle ◽  
Arrival Time ◽  
Gamma Ray ◽  
Weak Equivalence ◽  
Radio Bursts ◽  
Weak Equivalence Principle ◽  
Massive Galaxies ◽  
Binary Black Hole ◽  
Gravitational Theories

ABSTRACT The weak equivalence principle (WEP) is the cornerstone of gravitational theories. At the local scale, WEP has been tested to high accuracy by various experiments. On the intergalactic distance scale, WEP could be tested by comparing the arrival time of different messengers emitted from the same source. The gravitational time delay caused by massive galaxies is proportional to γ + 1, where the parameter γ is unity in general relativity. The values of γ for different massless particles should be different if WEP is violated, i.e. Δγ is used to indicate the deviation from WEP. So far, |Δγ| has been constrained with gamma-ray bursts, fast radio bursts, etc. Here, we report a new constraint of |Δγ| by using the gravitational wave data of binary black hole coalescences in the LIGO–Virgo catalogue GWTC-1. The best constraints imply that |Δγ| ≲ 10−15 at 90 per cent confidence level.

Precision tests of Einstein's Weak Equivalence Principle for antimatter

2000 ◽  
Vol 25 (6) ◽  
pp. 1245-1249 ◽  
Author(s):  
F.M. Huber ◽  
R.A. Lewis ◽  
E.W. Messerschmid ◽  
G.A. Smith
Keyword(s):  
Equivalence Principle ◽  
Weak Equivalence ◽  
Weak Equivalence Principle
Sign in / Sign up

Export Citation Format

Share Document