arXiv subjects

Kimihide Nishimura

Publications and source records attributed to Kimihide Nishimura.

9 recordsLinked to original sources

arXiv2026

General Relativistic Quantum Mechanics deriving Electroweak and Gravitational Interactions

A gauge theory with an indefinite metric without negative probabilities is given by extending quantum mechanics, where a general metric is introduced, and the invariance under the general linear transformation is imposed on the space of quantum states. On this basis, we construct and investigate a chiral sextet model, which has one more Lorentz symmetry in the gauge space, to derive much properties of the standard electroweak theory, and also Einstein gravity, when the double Lorentz symmetry spontaneously fuses into one.

physics.gen-ph↗

arXiv2024

Nambu-Goldstone Gravity and New Cosmology

The reformulation of gravity as the Nambu-Goldstone mode associated with broken gauge symmetry is given and applied to cosmology. We find that; the new gravity consists of a scalar mode and a tensor mode, of which the tensor mode corresponds to the Einstein gravity; the universe pulsates without spacial curvature; the gravitational constant increases from zero as the universe expands and decreases to zero as the universe contracts; the dark energy is identified with the sum of the gravitational energies of scalar and tensor modes, while the dark matter is the mirage of the gravitational energy caused by the projection into the $\Lambda$CDM spectrum; the gravitational equation dictates the cosmological constant to be zero; the universe begins with inflation, and the present age of the universe is approximately 550Gy.

physics.gen-ph↗

arXiv2022

Dual Spacetime Symmetry Breaking down to Einstein Gravity

Einstein action of gravity is obtained from a gauge theory, if our spacetime was once in two folds with a double Lorentz symmetry. After the dual symmetry breaks spontaneously, Lorentz symmetry absorbs gauge symmetry, while the gauge field begins to drive the vierbein and the spin connection. This gauge model of gravity has many bosons and fermions with negative norms, which will be undetectable. The consistency of these particles with the Copenhagen interpretation of wave functions, and their relation to the presence of dark matter as well as the absence of antimatter in the universe are discussed.

physics.gen-ph↗

arXiv2021

Extra equation of gravity induced by spontaneous local Lorentz symmetry breakdown

A model of spontaneous Lorentz violation in four dimension is given, which seems to provide a Lorentz invariant effective theory. An SU(2) Yang-Mills gauge field and an auxiliary U(1) vector field generate gravity and other interactions when they have vacuum expectation values. The emergent gravity is equivalent to conventional general relativity up to the third order terms in the Lagrangian. The coupling to matter, including spin-1/2 fermions, is also given correctly to this level. It remains to be seen whether this formalism reproduces the properties of black holes and other consequences obtained from Einstein's theory.

physics.gen-ph↗

arXiv2017

Principles for a unified picture of fermions

It is shown that a chiral SU(2) model can break Lorentz symmetry spontaneously at the Lagrangian level when gauge bosons become massive. This model seems to propose the principles and conceptual foundations leading to a unified picture of fermions, and may reduce the standard theory to a far simpler form. The model suggests describing leptons and quarks as quasi-excitations, while electromagnetic and strong interactions as secondary interactions mediated by Nambu-Goldstone bosons originating from spontaneous violations of global SU(2) and rotational symmetries. Both the possibility of observing Lorentz-violating phenomena and their magnitudes are discussed. The model also provides an alternative scenario for baryon and lepton asymmetries of the Universe.

physics.gen-ph↗

arXiv2017

Higgs-like mechanism for spontaneous spacetime symmetry breaking

The study of spontaneous breakdown of spacetime symmetries leads to the discovery of another type of Higgs mechanism operating in a chiral SU(2) model. Some of the Nambu-Goldstone vector mesons emergent from simultaneous violations of gauge and Lorentz symmetries are, in this case, absorbed by a left-handed doublet and endow one of the fermions with a right-handed state, while another part becomes emergent as photons. Accordingly, this mechanism allows a chiral fermion to acquire a mass, and it may enable the emergent theory to reproduce the electromagnetism equivalent to the QED sector in the standard theory. It is also mentioned that the "fermion-boson puzzle" known in the presence of a 't Hooft--Polyakov monopole does not exist in our theory.

physics.gen-ph↗

arXiv2016

QCD emergent from spontaneous breakdown of relativity

Spontaneous violation of relativistic invariance of the vacuum can derive quantum chromodynamics from an U(1) Higgs model including fermions, if the emergent theory is Lorentz invariant. In this model, the vacuum becomes anisotropic, and a fermion created on a triplet of spin-one vacua acquires degeneracy analogous to the color degrees of freedom. The Nambu-Goldstone bosons originating from the breakdown of rotational symmetry provide the quasi fermions with SU(3)$\times$U(1) effective interactions, which are interpretable as mediated by gluons and photons. The confinement of quasi quarks as well as that of Nambu-Goldstone gluons follow from the Lorentz invariance of the emergent theory.

physics.gen-ph↗

arXiv2014

Spontaneous Generation of Anisotropic Quasi-fermions

We show that two types of relativistic quasi-fermions can emerge from spontaneous gauge and Lorentz violations of a chiral SU(2) model. In the terminology given in the previous paper, the one consists of "quasi-leptons", and the other consists of "quasi-quarks" which are massless and have anisotropic dispersion relations characterized by constant vector potentials. A low energy approximation shows that quasi fermions of the latter type are interpretable as collective excitations of the BCS-type vacuum, the Cooper pairs of which form vector mesons. The same approximation reproduces further a generation structure similar to that of real quarks.

physics.gen-ph↗

arXiv2013

Detectability of Lorentz-violating potentials in a unified model of fermions

The detectability of the fermion-potentials appearing in a unified model of fermions is discussed from the viewpoint of an effective field theory. Although the fermion-potentials are effectively represented as terms similar to the $a$-coefficients in the theory of standard-model extension, their magnitudes are very large and their physical implications are different. A possibility is shown that the fermion-potentials are detectable by neither the deviations from conventional energy-momentum conservations, the neutrino-oscillations, the CPT-violation in neutral meson systems, nor the gravitational effects.

physics.gen-ph↗