Gauge invariance in flow line optics (Conference Presentation)

Abstract We point out the necessity of resolving the apparent gauge dependence in the quantum corrections of cosmological observables for Higgs-like inflation models. We highlight the fact that this gauge dependence is due to the use of an asymmetric background current which is specific to a choice of coordinate system in the scalar manifold. Favoring simplicity over complexity, we further propose a practical shortcut to gauge-independent inflationary observables by using effective potential obtained from a polar-like background current choice. We demonstrate this shortcut for several explicit examples and present a gauge-independent prediction of inflationary observables in the Abelian Higgs model. Furthermore, with Nielsen’s gauge dependence identities, we show that for any theory to all orders, a gauge-invariant current term gives a gauge-independent effective potential and thus gauge-invariant inflationary observables.

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A master exceptional field theory

Journal of High Energy Physics ◽

10.1007/jhep06(2021)185 ◽

2021 ◽

Vol 2021 (6) ◽

Author(s):

Guillaume Bossard ◽

Axel Kleinschmidt ◽

Ergin Sezgin

Keyword(s):

Field Theory ◽

Gauge Invariance ◽

Sigma Model ◽

Linear Equations ◽

Field Theories ◽

Gauge Invariant ◽

Non Linear ◽

Non Linear Equations

Abstract We construct a pseudo-Lagrangian that is invariant under rigid E11 and transforms as a density under E11 generalised diffeomorphisms. The gauge-invariance requires the use of a section condition studied in previous work on E11 exceptional field theory and the inclusion of constrained fields that transform in an indecomposable E11-representation together with the E11 coset fields. We show that, in combination with gauge-invariant and E11-invariant duality equations, this pseudo-Lagrangian reduces to the bosonic sector of non-linear eleven-dimensional supergravity for one choice of solution to the section condi- tion. For another choice, we reobtain the E8 exceptional field theory and conjecture that our pseudo-Lagrangian and duality equations produce all exceptional field theories with maximal supersymmetry in any dimension. We also describe how the theory entails non-linear equations for higher dual fields, including the dual graviton in eleven dimensions. Furthermore, we speculate on the relation to the E10 sigma model.

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The Effect of Flow Lines on the Mechanical Properties in Hot-Rolled Bearing Steel

Metals ◽

10.3390/met11030456 ◽

2021 ◽

Vol 11 (3) ◽

pp. 456

Author(s):

Dongsheng Qian ◽

Chengfei Ma ◽

Feng Wang

Keyword(s):

Mechanical Characterization ◽

Tensile Deformation ◽

Flow Line ◽

Plastic Property ◽

Bearing Steel ◽

Mechanical Anisotropy ◽

Flow Lines ◽

Significant Difference ◽

Hot Rolled ◽

Bearing Rings

Hot rolling is an essential process for the shape-forming of bearing steel. It plays a significant role in the formation and distribution of flow lines. In this work, the effect of flow lines is investigated by analyzing the microstructure and mechanical anisotropy of hot-rolled bearing steel. It was found that carbides rich with Cr and Mn elements are distributed unevenly along the flow-line direction of the hot-rolled bearing steel. Moreover, the mechanical characterization indicates that ultimate tensile strength and yield strength do not have any significant difference in two directions. Nevertheless, an ultrahigh section shrinkage of 57.51% is obtained in the 0° sample that has parallel flow lines, while 90° sample shows poor section shrinkage. The uneven distributed carbides will affect the direction and speed of crack propagation during tensile deformation. Therefore, the 0° and 90° samples exhibit great difference in plastic property. Meanwhile, after tensile deformation, a delaminated texture is observed in the flow lines, which may be caused by different degrees of deformation of grains due to the uneven distribution of carbides. The results of this work may provide guidance for controlling and optimizing flow lines in the manufacturing of bearing rings.

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Engineering Mathematical Analysis Method for Productivity Rate in Linear Arrangement Serial Structure Automated Flow Assembly Line

Mathematical Problems in Engineering ◽

10.1155/2015/592061 ◽

2015 ◽

Vol 2015 ◽

pp. 1-10

Author(s):

Tan Chan Sin ◽

Ryspek Usubamatov ◽

M. A. Fairuz ◽

Mohd Fidzwan B. Md. Amin Hamzas ◽

Low Kin Wai

Keyword(s):

Mathematical Model ◽

Failure Rate ◽

Mathematical Analysis ◽

Assembly Line ◽

Flow Line ◽

Analysis Method ◽

Machining Time ◽

Linear Arrangement ◽

Final Assembly ◽

Productivity Rate

Productivity rate (Q) or production rate is one of the important indicator criteria for industrial engineer to improve the system and finish good output in production or assembly line. Mathematical and statistical analysis method is required to be applied for productivity rate in industry visual overviews of the failure factors and further improvement within the production line especially for automated flow line since it is complicated. Mathematical model of productivity rate in linear arrangement serial structure automated flow line with different failure rate and bottleneck machining time parameters becomes the basic model for this productivity analysis. This paper presents the engineering mathematical analysis method which is applied in an automotive company which possesses automated flow assembly line in final assembly line to produce motorcycle in Malaysia. DCAS engineering and mathematical analysis method that consists of four stages known as data collection, calculation and comparison, analysis, and sustainable improvement is used to analyze productivity in automated flow assembly line based on particular mathematical model. Variety of failure rate that causes loss of productivity and bottleneck machining time is shown specifically in mathematic figure and presents the sustainable solution for productivity improvement for this final assembly automated flow line.

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All-plus helicity off-shell gauge invariant multigluon amplitudes at one loop

Journal of High Energy Physics ◽

10.1007/jhep12(2020)158 ◽

2020 ◽

Vol 2020 (12) ◽

Author(s):

Etienne Blanco ◽

Andreas van Hameren ◽

Piotr Kotko ◽

Krzysztof Kutak

Keyword(s):

Scattering Amplitudes ◽

Gauge Invariance ◽

Arbitrary Number ◽

Gauge Invariant

Abstract We calculate one loop scattering amplitudes for arbitrary number of positive helicity on-shell gluons and one off-shell gluon treated within the quasi-multi Regge kinematics. The result is fully gauge invariant and possesses the correct on-shell limit. Our method is based on embedding the off-shell process, together with contributions needed to retain gauge invariance, in a bigger fully on-shell process with auxiliary quark or gluon line.

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Monopole fluctuation of the CMB and its gauge invariance

Physical Review D ◽

10.1103/physrevd.103.063516 ◽

2021 ◽

Vol 103 (6) ◽

Author(s):

Sandra Baumgartner ◽

Jaiyul Yoo

Keyword(s):

Gauge Invariance

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GAUGE INVARIANCE AND CONSTRAINTS: OPEN GAUGE ALGEBRAS

International Journal of Modern Physics A ◽

10.1142/s0217751x92002519 ◽

1992 ◽

Vol 07 (22) ◽

pp. 5549-5561 ◽

Cited By ~ 1

Author(s):

KH. S. NIROV ◽

P.N. PYATOV ◽

A.V. RAZUMOV

Keyword(s):

Wide Class ◽

Gauge Invariance ◽

Poisson Brackets ◽

Hamiltonian Description ◽

Gauge Invariant

For a wide class of gauge-invariant systems with open gauge algebras the Hamiltonian description is constructed and the Poisson brackets of the constraints are calculated. It is shown that in the case under consideration there arise only first class constraints.

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A quantization of the electromagnetic field

Canadian Journal of Physics ◽

10.1139/p83-148 ◽

1983 ◽

Vol 61 (8) ◽

pp. 1172-1183

Author(s):

Anton Z. Capri ◽

Gebhard Grübl ◽

Randy Kobes

Keyword(s):

Hilbert Space ◽

Electromagnetic Field ◽

Gauge Invariance ◽

Free Field ◽

External Source ◽

Field Level ◽

Manifest Covariance ◽

The One ◽

Physical Spaces

Quantization of the electromagnetic field in a class of covariant gauges is performed on a positive metric Hilbert space. Although losing manifest covariance, we find at the free field level the existence of two physical spaces where Poincaré transformations are implemented unitarily. This gives rise to two different physical interpretations of the theory. Unitarity of the S operator for an interaction with an external source then forces one to postulate that a restricted gauge invariance must hold. This singles out one interpretation, the one where two transverse photons are physical.

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