Experimental hint for gravitational CP violation

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 matter. Here, a method based on high-energy Compton scattering is developed to measure the gravitational interaction of accelerated charged particles. Within that formalism, the Compton spectra measured at HERA rule out the speculated anti-gravity possibility for antimatter at a confidence level close to 100%. The same data, however, imply a gravitational CP violation around 13 GeV energies, by a maximal amount of [Formula: see text] for the charge and [Formula: see text] for the space parity. The detected asymmetry hints for a stronger gravitational coupling to left helicity electrons relative to right helicity positrons.

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Expanding Confusion: Common Misconceptions of Cosmological Horizons and the Superluminal Expansion of the Universe

Publications of the Astronomical Society of Australia ◽

10.1071/as03040 ◽

2004 ◽

Vol 21 (1) ◽

pp. 97-109 ◽

Cited By ~ 97

Author(s):

Tamara M. Davis ◽

Charles H. Lineweaver

Keyword(s):

General Relativity ◽

Confidence Level ◽

Speed Of Light ◽

Observable Universe ◽

Expansion Of The Universe ◽

Superluminal Expansion ◽

The Universe ◽

Recession Velocity ◽

Common Misconceptions ◽

Rule Out

AbstractWe use standard general relativity to illustrate and clarify several common misconceptions about the expansion of the universe. To show the abundance of these misconceptions we cite numerous misleading, or easily misinterpreted, statements in the literature. In the context of the new standard ΛCDM cosmology we point out confusions regarding the particle horizon, the event horizon, the ‘observable universe’ and the Hubble sphere (distance at which recession velocity = c). We show that we can observe galaxies that have, and always have had, recession velocities greater than the speed of light. We explain why this does not violate special relativity and we link these concepts to observational tests. Attempts to restrict recession velocities to less than the speed of light require a special relativistic interpretation of cosmological redshifts. We analyze apparent magnitudes of supernovae and observationally rule out the special relativistic Doppler interpretation of cosmological redshifts at a confidence level of 23σ.

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General Relativity

10.1093/oso/9780198822158.001.0001 ◽

2019 ◽

Cited By ~ 1

Author(s):

Steven Carlip

Keyword(s):

General Relativity ◽

High Energy Physics ◽

Hamiltonian Formulation ◽

Experimental Tests ◽

High Energy ◽

Gravitational Energy ◽

Field Equations ◽

Physics First ◽

Condensed Matter Theory ◽

Introductory Textbooks

This work is a short textbook on general relativity and gravitation, aimed at readers with a broad range of interests in physics, from cosmology to gravitational radiation to high energy physics to condensed matter theory. It is an introductory text, but it has also been written as a jumping-off point for readers who plan to study more specialized topics. As a textbook, it is designed to be usable in a one-quarter course (about 25 hours of instruction), and should be suitable for both graduate students and advanced undergraduates. The pedagogical approach is “physics first”: readers move very quickly to the calculation of observational predictions, and only return to the mathematical foundations after the physics is established. The book is mathematically correct—even nonspecialists need to know some differential geometry to be able to read papers—but informal. In addition to the “standard” topics covered by most introductory textbooks, it contains short introductions to more advanced topics: for instance, why field equations are second order, how to treat gravitational energy, what is required for a Hamiltonian formulation of general relativity. A concluding chapter discusses directions for further study, from mathematical relativity to experimental tests to quantum gravity.

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ENERGY ORDERING EFFECTS IN THE ARRIVAL DIRECTIONS OF ULTRA-HIGH ENERGY COSMIC RAYS MEASURED BY THE PIERRE AUGER OBSERVATORY

International Journal of Modern Physics E ◽

10.1142/s021830131104058x ◽

2011 ◽

Vol 20 (supp02) ◽

pp. 50-56

Author(s):

◽

PETER SCHIFFER

Keyword(s):

Cosmic Rays ◽

Magnetic Fields ◽

Charged Particles ◽

High Energy ◽

Pierre Auger Observatory ◽

Ultra High Energy ◽

High Energy Cosmic Rays ◽

Ordering Effects ◽

Arrival Directions

The Pierre Auger Observatory is the world's largest experiment for the measurement of ultra-high energy cosmic rays (UHECRs). These UHECRs are assumed to be to be charged particles, and thus are deflected in cosmic magnetic fields. Recent results of the Pierre Auger Observatory addressing the complex of energy ordering of the UHECRs arrival directions are reviewed in this contribution. So far no significant energy ordering has been observed.

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A theoretical discussion of the deviation of high energy charged particles in passing through magnetized iron

Journal of the Franklin Institute ◽

10.1016/s0016-0032(37)90100-5 ◽

1937 ◽

Vol 224 (1) ◽

pp. 105-106

Author(s):

W.F.G. Swann

Keyword(s):

Charged Particles ◽

High Energy ◽

Theoretical Discussion

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Pseudorapidity distribution of relativistic singly charged particles in heavy-ion collisions at high energy

Canadian Journal of Physics ◽

10.1139/p98-071 ◽

1999 ◽

Vol 77 (4) ◽

pp. 313-318 ◽

Cited By ~ 3

Author(s):

F -H Liu ◽

Y A Panebratsev

Keyword(s):

Experimental Data ◽

Heavy Ion Collisions ◽

Charged Particles ◽

Heavy Ion ◽

High Energy ◽

Pseudorapidity Distribution ◽

Ion Collisions ◽

Singly Charged

The pseudorapidity distribution of relativistic singly charged particles produced in high-energy heavy-ion collisions is described by the thermalized cylinder picture. The calculated results are in agreement with the experimental data of lead-induced interactions at 158A GeV/c. PACS Nos.:25.75.-q and 25.75.Dw

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THE HYDRODYNAMIC DESCRIPTION OF THE ENERGY AND CENTRALITY DEPENDENCES OF THE PSEUDORAPIDITY DISTRIBUTIONS OF THE PRODUCED CHARGED PARTICLES IN Au+Au COLLISIONS

International Journal of Modern Physics E ◽

10.1142/s0218301313500699 ◽

2013 ◽

Vol 22 (09) ◽

pp. 1350069 ◽

Cited By ~ 3

Author(s):

ZHIJIN JIANG ◽

QINGGUANG LI ◽

GUANXIANG JIANG

Keyword(s):

Hydrodynamic Model ◽

Charged Particles ◽

Heavy Ion ◽

High Energy ◽

Hydrodynamic Description ◽

Gaussian Form ◽

Ion Collisions ◽

Phobos Collaboration ◽

Rapidity Distributions ◽

Pseudorapidity Distributions

By using the revised Landau hydrodynamic model and taking into account the effect of leading particles, we discuss the pseudorapidity distributions of produced charged particles in high energy heavy-ion collisions. The charged particles resulted from the freeze-out of the matter produced in collisions possess the Gaussian-like rapidity distributions. The leading particles are assumed having the rapidity distributions of the Gaussian form with the normalization constant being equal to the number of participants, which can be figured out in theory. It is found that the results from the revised Landau hydrodynamic model together with the contributions from leading particles are well consistent with the experimental data carried out by BNL-RHIC-PHOBOS Collaboration in different centrality Au + Au collisions at energies of [Formula: see text], 130 and 62.4 GeV , respectively.

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