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Covariant formulation of spontaneous symmetry breaking in chiral quantum field theory
Il Nuovo Cimento A, 1977For the (SU2 ⊗SU2)-invariant model of Gursey a formulation is given in terms of a direct integral of Hilbert spaces. The structure of matrix elements, due to the spontaneous breakdown of the chiral symmetry is discussed.
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Il Nuovo Cimento A, 1975
We study the spontaneous break-down of symmetry in the exactly solvable Euclidean static ultra-local model. We show that there exists always a suitable interval for the arbitrary constants from which the Green’s functions depend, and in correspondence a suitable valueλ cof the coupling constant, such that ...
G. Scarpetta, G. Vilasi
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We study the spontaneous break-down of symmetry in the exactly solvable Euclidean static ultra-local model. We show that there exists always a suitable interval for the arbitrary constants from which the Green’s functions depend, and in correspondence a suitable valueλ cof the coupling constant, such that ...
G. Scarpetta, G. Vilasi
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1984
In the framework of the standard hot big bang cosmological model, the present density, temperature (TO ≈ 3°K) and Hubble constant (HO ≈ 10-10 years-1) are extrapolated back in time according to the Friedmann expansion law a(t) ~ t1/2 (or a(t) ~ t2/3).
V. G. Lapchinsky +3 more
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In the framework of the standard hot big bang cosmological model, the present density, temperature (TO ≈ 3°K) and Hubble constant (HO ≈ 10-10 years-1) are extrapolated back in time according to the Friedmann expansion law a(t) ~ t1/2 (or a(t) ~ t2/3).
V. G. Lapchinsky +3 more
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Annals of Physics, 1976
Abstract We prove that a Symanzik-Nelson positive quantum field theory, i.e., a quantum field theory derived from a Euclidean field theory, has a unique decomposition into pure phases which preserves Symanzik-Nelson positivity and Poincare covariance. We derive useful sufficient conditions for the breakdown of an internal symmetry of such a theory in
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Abstract We prove that a Symanzik-Nelson positive quantum field theory, i.e., a quantum field theory derived from a Euclidean field theory, has a unique decomposition into pure phases which preserves Symanzik-Nelson positivity and Poincare covariance. We derive useful sufficient conditions for the breakdown of an internal symmetry of such a theory in
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Symmetry breaking due to quantum fluctuations in the massless λϕ4theory
Journal of Physics G: Nuclear Physics, 1982It is shown that quantum fluctuations can act as the driving mechanism of instability leading to spontaneous symmetry breaking in the massless lambda phi 4 theory.
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Possible role of symmetry breaking in quantum measurement theory
Physical Review A, 1986, Zimányi, , Vladár
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Symmetry Breaking as Boundary Constraint Selection in Quantum Field Theory
This provocative theoretical physics paper challenges one of the most mysterious aspects of modern quantum field theory: why does nature seem to "spontaneously" select one vacuum state from countless identical possibilities when fundamental symmetries break?openaire +1 more source
Quantum guidelines for solid-state spin defects
Nature Reviews Materials, 2021Gary Wolfowicz +2 more
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Weyl, Dirac and high-fold chiral fermions in topological quantum matter
Nature Reviews Materials, 2021M Zahid Hasan +2 more
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InP colloidal quantum dots for visible and near-infrared photonics
Nature Reviews Materials, 2023Guilherme Almeida
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