Related papers: Fermion observables for Lorentz violation
An effective Proca Lagrangian action is used to address the vector condensation Lorentz violation effects on the equation of state of the strongly interacting fermions system. The interior quantum fluctuation effects are incorporated as an…
Infrared, optical, and ultraviolet spectropolarimetry of cosmological sources is used to constrain the pure electromagnetic sector of a general Lorentz-violating standard-model extension. The coefficients for Lorentz violation are bounded…
Physics from beyond the Standard Model can induce four fermion operators involving a quark, an anti-quark, a lepton and an anti-lepton. The coefficients of these operators can be constrained by various observations. We update the bounds…
We study two (massless free field) models, a photon/photino model with a vector gauge field and a Majorana spinor field, and a Wess-Zumino model. They each exhibit Lorentz symmetry violation but retain, in an appropriate way, the…
Lorentz invariance violation (LIV) is often described by dispersion relations of the form $E_i^2=m_i^2+p_i^2+\delta_{i,n} E^{2+n}$ with delta different based on particle type $i$, with energy $E$, momentum $p$ and rest mass $m$. Kinematics…
In this paper, we describe the quantum electrodynamics added by Lorentz-violating CPT-even terms in the context of the standard model extension. We focus our attention on the fermion sector, represented by the CPT-even symmetric…
Lorentz invariance (LI) is a foundational principle of modern physics, yet its possible violation (LIV) remains an intriguing window to physics beyond the Standard Model. While stringent constraints exist in the electromagnetic and hadronic…
We study different phenomenological signatures associated with new spin-2 particles. These new degrees of freedom, that we call hidden gravitons, arise in different high-energy theories such as extra-dimensional models or extensions of…
Light scalar particles with couplings of sub-gravitational strength, which can generically be called 'dilatons', can produce violations of the equivalence principle. However, in order to understand experimental sensitivities one must know…
Relating the effective Lorentz violation coefficients for composite particles to the coefficients for their constituent fields is a challenging problem. We calculate the Lorentz violation coefficients relevant to the dynamics of an…
A new physics scenario shows that four-fermion operators of Nambu-Jona-Lasinio (NJL) type have a strong-coupling UV fixed point, where composite fermions $F$ (bosons $\Pi$) form as bound states of three (two) SM elementary fermions and they…
In string theory, a scalar field often appears as a moduli of a geometrical configuration of D-branes in higher dimensional space. In the low energy effective theory on D-branes, the distance between D-branes is translated into the energy…
We consider a supersymmetric model that uses partial compositeness to explain the fermion mass hierarchy and predict the sfermion mass spectrum. The Higgs and third-generation matter superfields are elementary, while the first two matter…
We consider neutrino oscillations in the minimal Standard-Model Extension describing general Lorentz and CPT violation. Among the models without neutrino mass differences is one with two degrees of freedom that reproduces most major…
In this thesis we are interested in understanding how Lorentz symmetry violation can affect some features of fermion dynamics and, perhaps, help to solve some well-known problems in particle physics, such as the origin of neutrino masses…
A modified Dirac equation with general Lorentz- and CPT-violating operators in the electromagnetic field is studied. Constraints on and possible sensitivities to Lorentz-violating coefficients in the nonminimal sector up to mass-dimension…
We consider Lorentz violation in supersymmetric extensions of the standard model. We perform a spurion analysis to show that, in the simplest natural constructions, the resulting supersymmetry-breaking masses are tiny. In the process, we…
Unparticles from hidden conformal sectors provide qualitatively new possibilities for physics beyond the standard model. In the theoretical framework of minimal models, we clarify the relation between energy scales entering various…
In this paper we study a $2+1$ dimensional system in which fermions are coupled to the self-dual topological vortex in $U(1) \times U(1)$ Chern-Simons theory, where both $U(1)$ gauge symmetries are spontaneously broken. We consider two…
In celestial conformal field theory, gluons are represented by primary fields with dimensions $\Delta=1+i\lambda$, $\lambda\in\mathbb{R}$ and spin $J=\pm 1$, in the adjoint representation of the gauge group. All two- and three-point…