Condensate preserving the symmetry of the Lagrangian. Symmetry breakdown

Austenite grains that underwent the f.c.c. to b.c.c. (or b.c.t.) transformation are typically composed of 24 Kurdjumov–Sachs variants that can be categorized by three axes of Bain transformations; thus, a complete transformation generally displays 3-fold symmetry in (001) pole figures. In the present work, crystallographic symmetry in 42CrMo4 steel austempered below martensite start temperature was investigated with the help of the orientation distribution function (ODF) analysis based on the FEG-SEM/EBSD technique. It is shown that, upon phase transformations, the specimens contained 6-fold symmetry in all (001), (011), and (111) pole figures of an ODF. The ODF analysis, verified by theoretical modeling, showed that under plane-strain conditions cracks prefer to propagate through areas strongly offset by the high symmetry. The origin of high symmetry was investigated, and the mechanism of the symmetry breakdown was explained.

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Symmetry breakdown and coupling constants of leptons

Anais da Academia Brasileira de Ciências ◽

10.1590/s0001-37652007000200002 ◽

2007 ◽

Vol 79 (2) ◽

pp. 195-208 ◽

Cited By ~ 1

Author(s):

Gil C. Marques ◽

Dominique Spehler

Keyword(s):

Coupling Constants ◽

Electroweak Interactions ◽

New Approach ◽

Fundamental Interactions ◽

Electromagnetic Interactions ◽

Symmetry Breakdown ◽

A Value ◽

Intermediate Bosons ◽

The One ◽

The Way

Based on a new approach to symmetries of the fundamental interactions we deal, in this paper, with the electroweak interactions of leptons. We show that the coupling constants, arising in the way leptons are coupled to intermediate bosons, can be understood as parameters associated to the breakdown of SU(2) and parity symmetries. The breakdown of both symmetries is characterized by a new parameter (the asymetry parameter) of the electroweak interactions. This parameter gives a measure of the strength of breakdown of symmetries. We analyse the behaviour of the theory for three values of this parameter. The most relevant value is the one for which only the electromagnetic interactions do not break parity (the maximally allowed left-right asymetric theory). Maximamally allowed parity asymmetry is a requirement that is met for a value of Weinberg's theta-angle that is quite close to the experimental value of this parameter.

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Continuous Symmetry Breakdown in 2+ε Dimension: The Non-Linear σ Model

New Developments in Quantum Field Theory and Statistical Mechanics Cargèse 1976 ◽

10.1007/978-1-4615-8918-1_5 ◽

1977 ◽

pp. 131-142

Author(s):

J. Zinn-Justin

Keyword(s):

Continuous Symmetry ◽

Symmetry Breakdown ◽

Non Linear

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Symmetry breakdown of electron emission in extreme ultraviolet photoionization of argon

Nature Communications ◽

10.1038/s41467-018-07152-7 ◽

2018 ◽

Vol 9 (1) ◽

Cited By ~ 17

Author(s):

M. Ilchen ◽

G. Hartmann ◽

E. V. Gryzlova ◽

A. Achner ◽

E. Allaria ◽

...

Keyword(s):

Electron Emission ◽

Extreme Ultraviolet ◽

Symmetry Breakdown

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Symmetry Breakdown in Franckeite: Spontaneous Strain, Rippling and Interlayer Moiré

10.26434/chemrxiv.9491261 ◽

2019 ◽

Author(s):

Riccardo Frisenda ◽

Gabriel Sanchez-Santolino ◽

Nikos Papadopoulos ◽

Joanna Urban ◽

Michal Baranowski ◽

...

Keyword(s):

Optical Properties ◽

Plane Strain ◽

Van Der Waals ◽

Van Der Waals Interaction ◽

Spatial Modulation ◽

Two Dimensional ◽

Spontaneous Strain ◽

Strain Profile ◽

Symmetry Breakdown ◽

Naturally Occurring

Franckeite is a naturally occurring layered mineral with a structure composed of alternating stacks of SnS2-like and PbS-like layers. Although this superlattice is composed of a sequence of isotropic two-dimensional layers, it exhibits a spontaneous rippling that makes the material structurally anisotropic. We demonstrate that this rippling comes hand in hand with an inhomogeneous in-plane strain profile and anisotropic electrical, vibrational and optical properties. We argue that this symmetry breakdown results from a spatial modulation of the van der Waals interaction between layers due to the SnS2-like and PbS-like lattices incommensurability.

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