Related papers: Symmetry Improved CJT Effective Action
A proof of Goldstone's theorem is given for the case in which global chiral symmetry is dynamically broken. The proof highlights a needed consistency between the exact Schwinger--Dyson equation for the fermion propagator and the exact…
In the context of conventional quantum field theory, we present a general Lorentz-violating extension of the minimal SU(3) x SU(2) x U(1) standard model including CPT-even and CPT-odd terms. It can be viewed as the low-energy limit of a…
The Ward identities associated with spontaneously broken symmetries can be saturated by Goldstone bosons. However, when space-time symmetries are broken, the number of Goldstone bosons necessary to non-linearly realize the symmetry can be…
If violation of Lorentz and CPT symmetry is introduced into the fermion sector of conventional quantum electrodynamics, then the Chern-Simons term is radiatively induced with finite nonzero coefficient, as well as the Maxwell term is with…
In two dimensional conformal field theories the limit of large central charge plays the role of a semi-classical limit. Certain universal observables, such as conformal blocks involving the exchange of the identity operator, can be expanded…
We formulate a generalization of Higgs effective field theory (HEFT) including arbitrary number of extra neutral and charged Higgs bosons (generalized HEFT, GHEFT) to describe non-minimal electroweak symmetry breaking models. Using the…
We quantize a particle confined to move on a torus knot satisfying constraint condition ($p \theta + q \phi) \approx 0$, within the context of a geometrically motivated approach - the Faddeev-Jackiw formalism. We also deduce the constraint…
We describe recent progress in understanding the continuous symmetry properties of non-Hermitian, PT-symmetric quantum field theories. Focussing on a simple non-Hermitian theory composed of one complex scalar and one complex pseudoscalar,…
The temperature dependence of the sigma meson and pion masses is studied in the framework of the O(N) model. The Cornwall-Jackiw-Tomboulis formalism is applied to derive gap equations for the masses in the Hartree and large-N…
Supersymmetric extensions of the 1D and 2D Swanson models are investigated by applying the conformal bridge transformation (CBT) to the first order Berry-Keating Hamiltonian multiplied by $i$ and its conformally neutral enlargements. The…
Temperature has a significant effect on the properties of quantum field theories (QFTs) with a spontaneously broken symmetry, in particular on the massless Goldstone bosons that exist in the vacuum state. It has recently been shown using…
We study the homogeneous breaking of spatial translation symmetry concomitantly with the spontaneous breaking of other internal and spacetime symmetries, including dilations. We use the symmetry-breaking pattern as the only input to derive,…
We investigate the noncommutative analogue of the spontaneously broken linear sigma model at the one-loop quantum level. In the commutative case, renormalization of a theory with a spontaneously broken continuous global symmetry depends on…
This thesis examines low-energy effective actions of supersymmetric quantum field theories. These actions contain information about the low-energy field content and dynamics of quantum field theories and are essential for understanding…
Hellerman et al. (arXiv:1505.01537) have shown that in a generic CFT the spectrum of operators carrying a large U(1) charge can be analyzed semiclassically in an expansion in inverse powers of the charge. The key is the operator state…
We discuss the effective field theory of large scale structure in terms of a single scalar degree of freedom, corresponding to the velocity potential of the matter fluid in a $\Lambda$CDM universe. This cosmic ``pion'' field is nonlinearly…
We systematically study the anomaly inflow by the bulk Chern-Simons (CS) theory in a slice of five-dimensional anti-de Sitter spacetime ($\text{AdS}_5$). The introduction of UV and IR 3-branes makes the anomaly story remarkably rich and…
Recently, the steady states of non-unitary free fermion dynamics are found to exhibit novel critical phases with power-law squared correlations and a logarithmic subsystem entanglement. In this work, we theoretically understand the…
We introduce a systematic method to derive the effective action for domain walls directly from the scalar field theory that gives rise to their solitonic solutions. The effective action for the Goldstone mode, which characterizes the…
We investigate spontaneous symmetry breaking within the linear sigma model with the SU(2)xU(1) internal symmetry at finite chemical potential, which was suggested as a model for kaon condensation in the CFL phase of dense quark matter.…