Nonlinear Realizations. I. The Role of Goldstone Bosons

Abstract A class of chiral gauge theories is studied with accidentally-stable pseudo Nambu-Goldstone bosons playing the role of dark matter (DM). The gauge group contains a vector-like dark color factor that confines at energies larger than the electroweak scale, and a U(1)D factor that remains weakly coupled and is spontaneously broken. All new scales are generated dynamically, including the DM mass, and the IR dynamics is fully calculable. We analyze minimal models of this kind with dark fermions transforming as non-trivial vector-like representations of the Standard Model (SM) gauge group. In realistic models, the DM candidate is a SM singlet and comes along with charged partners that can be discovered at high-energy colliders. The phenomenology of the lowest-lying new states is thus characterized by correlated predictions for astrophysical observations and laboratory experiments.

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THE ROLE OF TRANSLATIONAL INVARIANCE IN NONLINEAR GAUGE THEORIES OF GRAVITY

International Journal of Geometric Methods in Modern Physics ◽

10.1142/s0219887808002734 ◽

2008 ◽

Vol 05 (02) ◽

pp. 253-264 ◽

Cited By ~ 4

Author(s):

J. MARTÍN ◽

A. TIEMBLO

Keyword(s):

Degrees Of Freedom ◽

Critical Length ◽

Weak Field ◽

Translational Invariance ◽

Goldstone Bosons ◽

Theories Of Gravity ◽

Nonlinear Gauge ◽

Dynamical Degrees ◽

Gauge Theory Of Gravity

The internal structure of the tetrads in a Poincaré nonlinear gauge theory of gravity is considered. Minkowskian coordinates becomes dynamical degrees of freedom playing the role of Goldstone bosons of the translations. A critical length allowing a covariant expansion similar to the weak field approach is deduced, the zeroth order metric being maximally symmetric (Minkowskian in some cases).

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Where have all the Goldstone bosons gone?

Modern Physics Letters A ◽

10.1142/s0217732314500461 ◽

2014 ◽

Vol 29 (09) ◽

pp. 1450046 ◽

Cited By ~ 1

Author(s):

G. S. Guralnik ◽

C. R. Hagen

Keyword(s):

Vector Meson ◽

Gauge Theories ◽

Broken Symmetry ◽

Goldstone Theorem ◽

Massive Vector ◽

Longitudinal Modes ◽

Goldstone Bosons ◽

Physical Spectrum ◽

Covariant Gauge

According to a commonly held view of spontaneously broken symmetry in gauge theories, troublesome Nambu–Goldstone bosons are effectively eliminated by turning into longitudinal modes of a massive vector meson. This note shows that, this is not in fact, a consistent view of the role of Nambu–Goldstone bosons in such theories. These particles necessarily appear as gauge excitations, whenever they are formulated in a manifestly covariant gauge. The radiation gauge provides therefore the dual advantage of circumventing the Goldstone theorem and making evident the disappearance of these particles from the physical spectrum.

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CHIRAL LAGRANGIANS FOR BARYONS COUPLED TO MASSIVE SPIN-1 FIELDS

International Journal of Modern Physics A ◽

10.1142/s0217751x96002376 ◽

1996 ◽

Vol 11 (29) ◽

pp. 5183-5202 ◽

Cited By ~ 44

Author(s):

B. BORASOY ◽

ULF-G. MEIßNER

Keyword(s):

Tensor Field ◽

Form Factors ◽

Meson Exchange ◽

Energy Field ◽

Goldstone Bosons ◽

Formal Equivalence ◽

Massive Spin ◽

Pion Nucleon ◽

Higher Order Corrections

We analyze the effective low energy field theory of Goldstone bosons and baryons chirally coupled to massive spin-1 fields. We use the electromagnetic baryon form factors to demonstrate the formal equivalence between the vector and the tensor field formulation for the spin-1 fields. We also discuss the origin of the so-called Weinberg term in pion–nucleon scattering and the role of ρ meson exchange. Chirally coupled vector mesons do not give rise to this two-pion nucleon seagull interaction but rather to higher order corrections. Some problems of the formal equivalence arising in higher orders and related to loops are touched upon.

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