scholarly journals Minding one’s P’s and Q’s: From the one loop effective action in quantum field theory to classical transport theory

2000 ◽  
Vol 62 (4) ◽  
Author(s):  
Jamal Jalilian-Marian ◽  
Sangyong Jeon ◽  
Raju Venugopalan ◽  
Jens Wirstam
Keyword(s):  
Field Theory ◽  
Quantum Field Theory ◽  
Effective Action ◽  
Transport Theory ◽  
Quantum Field ◽  
The One ◽  
Classical Transport

Effective action of in Krein space quantization

2017 ◽  
Vol 95 (12) ◽  
pp. 1239-1241 ◽  
Author(s):  
B. Forghan ◽  
S. Razavi
Keyword(s):  
Field Theory ◽  
Quantum Field Theory ◽  
Effective Action ◽  
Regularization Method ◽  
Krein Space ◽  
Quantum Field ◽  
Kreĭn Space ◽  
Finite Solution ◽  
The One ◽  
Krein Space Quantization

The appearance of divergence creates computational issues in the process of calculating the one-loop effective action of [Formula: see text] in quantum field theory. In this paper, it is demonstrated that using Krein space quantization with Ford’s method of fluctuated metrics, divergence can be removed and that without using any traditional regularization method, it is possible to arrive at a finite solution for the effective action.

scholarly journals COMMENTS ABOUT THE GEOMETRY OF NONLINEAR SIGMA MODELS

1987 ◽  
Vol 02 (06) ◽  
pp. 1763-1772 ◽  
Author(s):  
ROBERT COQUEREAUX
Keyword(s):  
Field Theory ◽  
Quantum Field Theory ◽  
Sigma Models ◽  
Effective Action ◽  
Quantum Field ◽  
Geometrical Meaning ◽  
Perturbative Quantum ◽  
Perturbative Quantum Field Theory ◽  
The One ◽  
Nonlinear Sigma Models

Geometrical aspects of several classes of σ models are studied. The geometrical meaning of perturbative quantum field theory is discussed in the content of nonlinear σ models. Results on the one-loop effective action are recovered and generalized.

scholarly journals ON THE QUANTUM THEORY OF MASSLESS SPIN-3/2 FIELD IN MINKOWSKI SPACETIME

2006 ◽  
Vol 03 (07) ◽  
pp. 1303-1312 ◽  
Author(s):  
WEIGANG QIU ◽  
FEI SUN ◽  
HONGBAO ZHANG
Keyword(s):  
Field Theory ◽  
Quantum Field Theory ◽  
Quantum Theory ◽  
Casimir Effect ◽  
Minkowski Spacetime ◽  
Quantum Field ◽  
Explicit Result ◽  
Massless Spin ◽  
The Many ◽  
The One

From the modern viewpoint and by the geometric method, this paper provides a concise foundation for the quantum theory of massless spin-3/2 field in Minkowski spacetime, which includes both the one-particle's quantum mechanics and the many-particle's quantum field theory. The explicit result presented here is useful for the investigation of spin-3/2 field in various circumstances such as supergravity, twistor programme, Casimir effect, and quantum inequality.

MESON-DIQUARK LOOP EXPANSION

1993 ◽  
Vol 08 (02) ◽  
pp. 277-300 ◽  
Author(s):  
M. LUTZ ◽  
J. PRASCHIFKA
Keyword(s):  
Field Theory ◽  
Quantum Field Theory ◽  
Effective Action ◽  
Degrees Of Freedom ◽  
Auxiliary Field ◽  
Quantum Field ◽  
Field Approach ◽  
Loop Expansion ◽  
Quark Models

We consider a general (nonlocal) four-fermion quantum field theory and show how the Cornwall-Jackiw-Tomboulis effective action can be systematically expanded in the number, η, of composite, bose loops. This is achieved by the introduction of auxiliary, bilocal fields which describe fermion-fermion and fermion-antifermion correlations. The η expansion can be understood as a generalization of the [Formula: see text] expansion and is of particular interest in quark models, for example, where the bilocal fields can be identified with meson and diquark degrees of freedom. Comparison with the usual loop (ħ) expansion reveals some unusual characteristics of the η expansion and throws light on recent studies of diquark degrees of freedom in which the auxiliary field approach is used.

scholarly journals Locality and General Vacua in Quantum Field Theory

2021 ◽  
Author(s):  
Daniele Colosi ◽  
◽  
Robert Oeckl ◽  
◽  
◽  
...  
Keyword(s):  
Field Theory ◽  
Quantum Field Theory ◽  
Hilbert Space ◽  
Vacuum State ◽  
Quantum Field Theories ◽  
Quantum Field ◽  
Algebraic Quantum ◽  
Particle Pairs ◽  
The One ◽  
Gns Construction

We extend the framework of general boundary quantum field theory (GBQFT) to achieve a fully local description of realistic quantum field theories. This requires the quantization of non-Kähler polarizations which occur generically on timelike hypersurfaces in Lorentzian spacetimes as has been shown recently. We achieve this in two ways: On the one hand we replace Hilbert space states by observables localized on hypersurfaces, in the spirit of algebraic quantum field theory. On the other hand we apply the GNS construction to twisted star-structures to obtain Hilbert spaces, motivated by the notion of reflection positivity of the Euclidean approach to quantum field theory. As one consequence, the well-known representation of a vacuum state in terms of a sea of particle pairs in the Hilbert space of another vacuum admits a vast generalization to non-Kähler vacua, particularly relevant on timelike hypersurfaces.

scholarly journals 𝒫𝒯-symmetric quantum field theory on the noncommutative spacetime

2019 ◽  
Vol 35 (05) ◽  
pp. 2050012
Author(s):  
Oleg O. Novikov
Keyword(s):  
Field Theory ◽  
Quantum Field Theory ◽  
Scattering Amplitude ◽  
Quantum Field ◽  
Leading Order ◽  
Symmetric Quantum ◽  
Noncommutative Spacetime ◽  
T Matrix ◽  
The One ◽  
New Formula

We consider the [Formula: see text]-symmetric quantum field theory on the noncommutative spacetime with angular twist and construct its pseudo-Hermitian interpretation. We explore the differences between internal and spatial parities in the context of the angular twist and for the latter we find new [Formula: see text]-symmetric interactions that are nontrivial only for the noncommutative spacetime. We reproduce the same formula for the leading order T-matrix of the equivalent Hermitian model as the one obtained earlier for the quantum field theory on the commutative spacetime. This formula implies that the leading order scattering amplitude preserves the symmetries of the noncommutative geometry if they are not broken in the non-Hermitian formulation.

Sign in / Sign up

Export Citation Format

Share Document