New Experimental Results on the Lower Limits of Local Lorentz Invariance

Torsion-based modified theories of gravity, such as [Formula: see text] gravity, are arguably one of the very few “true” modified gravities based on well-defined geometric structures. However, the original formulation explicitly works in a specific choice of frame, which has led to considerable amount of confusion in the literature about these theories breaking local Lorentz invariance. Pathological properties such as superluminal propagation and the lack of well-posedness of Cauchy problem were found to plague [Formula: see text] gravity. Recent effort to “covariantize” [Formula: see text] gravity has, however, renewed interests in this subject. In this proceeding paper, we review and discuss issues concerning the actual number of degrees of freedom in [Formula: see text] gravity, and how this might relate to the aforementioned pathologies.

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UNEXPECTED BEHAVIOR IN THE CROSSING OF MICROWAVE AND OPTICAL BEAMS

Modern Physics Letters B ◽

10.1142/s0217984905009274 ◽

2005 ◽

Vol 19 (27) ◽

pp. 1403-1410 ◽

Cited By ~ 4

Author(s):

E. ALLARIA ◽

R. MEUCCI ◽

D. MUGNAI ◽

A. RANFAGNI ◽

C. RANFAGNI

Keyword(s):

Lorentz Invariance ◽

Point Of View ◽

Experimental Results ◽

Light Velocity ◽

Broken Lorentz Invariance ◽

Points Of View ◽

Optical Beams ◽

Definite Solution ◽

Unexpected Behavior

The question of the superluminal speed of information was stopped at crossroads in the last few years. According to one point of view, this speed must be limited to the light velocity in vacuum, whereas a different point of view is more open in this respect and, under specific conditions, this limit is considered surmountable. Very recently, a third approach (based on the hypothesis of a local broken Lorentz-invariance) was proposed and, if confirmed, would go beyond the controversy of the two points of view mentioned above. It is therefore worthwhile to recall attention to this problem, which is far from having a definite solution. The present paper reports some experimental results (similar to those of Ref. 1) which can contribute to these discussions, and also considers the fact that they seem to give some support to the aforesaid third approach, although revised in terms of decaying waves.

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Diffeomorphism Invariance and Local Lorentz Invariance

Advances in Applied Clifford Algebras ◽

10.1007/s00006-008-0109-4 ◽

2008 ◽

Vol 18 (3-4) ◽

pp. 945-961 ◽

Cited By ~ 1

Author(s):

Roldão da Rocha ◽

Waldyr A. Rodrigues

Keyword(s):

Lorentz Invariance ◽

Diffeomorphism Invariance ◽

Local Lorentz Invariance

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PRINCIPLES OF EINSTEIN–FINSLER GRAVITY AND PERSPECTIVES IN MODERN COSMOLOGY

International Journal of Modern Physics D ◽

10.1142/s0218271812500721 ◽

2012 ◽

Vol 21 (09) ◽

pp. 1250072 ◽

Cited By ~ 45

Author(s):

SERGIU I. VACARU

Keyword(s):

General Relativity ◽

Lorentz Invariance ◽

Frame Structure ◽

Relativity Theory ◽

Finsler Metrics ◽

Finsler Spaces ◽

Modern Cosmology ◽

Gravity Theories ◽

Tangent Bundles ◽

Local Lorentz Invariance

We study the geometric and physical foundations of Finsler gravity theories with metric compatible connections defined on tangent bundles, or (pseudo) Riemannian manifolds, endowed with nonholonomic frame structure. Several generalizations and alternatives to Einstein gravity are considered, including modifications with broken local Lorentz invariance. It is also shown how such theories (and general relativity) can be equivalently re-formulated in Finsler like variables. We focus on prospects in modern cosmology and Finsler acceleration of Universe. Einstein–Finsler gravity theories are elaborated following almost the same principles as in the general relativity theory but extended to Finsler metrics and connections. Finally, some examples of generic off-diagonal metrics and generalized connections, defining anisotropic cosmological Einstein–Finsler spaces are analyzed; certain criteria for the Finsler accelerating evolution are formulated.

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Lorentz Violation in Torsional Antenna

Foundations of Science ◽

10.1007/s10699-020-09710-z ◽

2020 ◽

Author(s):

Fabio Cardone ◽

Gianni Albertini ◽

Domenico Bassani

Keyword(s):

Magnetic Field ◽

Lorentz Invariance ◽

Lorentz Violation ◽

General Rule ◽

Torsion Angles ◽

The Past ◽

Electro Magnetic Field ◽

Log Periodic Antenna ◽

Electro Magnetic ◽

Local Lorentz Invariance

Abstract A torsional-antenna and a log-periodic antenna are used as a source and an analyzer, respectively, to investigate the possible anomalies of an electro-magnetic field. An unexpected isotropic signal has been detected using those torsion angles, which correspond to a breakdown of the Local Lorentz Invariance, which was found in the past. This coincidence is interpreted as the recovery of a lost symmetry by torqueing the antenna, thus putting in evidence that this Lorentz violation is of angular nature. Introducing a new physical dimension—not only a mathematical dimension as a way to rearrange some equations—is here proposed as a general rule to recover the lost symmetry.

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Nuclear metamorphosis in mercury

International Journal of Modern Physics B ◽

10.1142/s0217979215502392 ◽

2016 ◽

Vol 30 (01) ◽

pp. 1550239

Author(s):

F. Cardone ◽

G. Albertini ◽

D. Bassani ◽

G. Cherubini ◽

E. Guerriero ◽

...

Keyword(s):

Solid State ◽

Gamma Radiation ◽

Neutron Emission ◽

Lorentz Invariance ◽

Atomic Weight ◽

Space Time ◽

Atomic Mass ◽

Aisi 304 ◽

Aisi 304 Steel ◽

Local Lorentz Invariance

The conditions of local Lorentz invariance (LLI) breakdown, obtained during neutron emission from a sonicated cylindrical bar of AISI 304 steel, were reproduced in a system made of a mole of mercury. After 3 min, a part of the liquid transformed into solid state material, in which isotopes were found with both higher and lower atomic mass with respect to the starting material. Changes in the atomic weight without production of gamma radiation and radionuclides are made possible by deformed space–time reactions.

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