Vacuum expectation value
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Unifying Inflation with the Axion, Dark Matter, Baryogenesis, and the Seesaw Mechanism Open
A minimal extension of the standard model (SM) with a single new mass scale and providing a complete and consistent picture of particle physics and cosmology up to the Planck scale is presented. We add to the SM three right-handed SM-singl…
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Manifestly Local Theory of Vacuum Energy Sequestering Open
We present a manifestly local, diffeomorphism invariant, and locally Poincaré invariant formulation of vacuum energy sequestering. In this theory, quantum vacuum energy generated by matter loops is canceled by auxiliary fields. The auxilia…
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Fermionic dark matter with pseudo-scalar Yukawa interaction Open
We consider a renormalizable extension of the standard model whose fermionic dark matter (DM) candidate interacts with a real singlet pseudo-scalar via a pseudo-scalar Yukawa term while we assume that the full Lagrangian is CP-conserved in…
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Implications of the absence of high-mass radion signals Open
Given the disappearance of the 750 GeV di-photon LHC signal and the absence of signals at high mass in this and other channels, significant constraints on the mixed Higgs-radion of the five-dimensional Randall-Sundrum model arise. By combi…
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Rotating fermions inside a cylindrical boundary Open
We study a quantum fermion field inside a cylinder in Minkowski space-time. On the surface of the cylinder, the fermion field satisfies either spectral or MIT bag boundary conditions. We define rigidly-rotating quantum states in both cases…
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The Higgs vacuum uplifted: revisiting the electroweak phase transition with a second Higgs doublet Open
The existence of a second Higgs doublet in Nature could lead to a cosmological first order electroweak phase transition and explain the origin of the matter-antimatter asymmetry in the Universe. We explore the parameter space of such a two…
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Coherent relaxion dark matter Open
We show that relaxion, that addresses the hierarchy problem, can account for\nthe observed dark matter (DM) relic density. The setup is similar to the case\nof axion DM models topped with a dynamical misalignment mechanism. After the\nrehe…
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Fermionic Schwinger effect and induced current in de Sitter space Open
We explore Schwinger effect of spin 1/2 charged particles with static electric field in 1+3 dimensional de Sitter spacetime. We analytically calculate the vacuum expectation value of the spinor current which is induced by the produced part…
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Accidental Peccei-Quinn Symmetry Protected to Arbitrary Order Open
A SU(N)_{L}×SU(N)_{R} gauge theory for a scalar multiplet Y transforming in the bifundamental representation (N,N[over ¯]) preserves, for N>4, an accidental U(1) symmetry first broken at operator dimension N. A vacuum expectation value for…
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Electroweak vacuum stability and diphoton excess at 750 GeV Open
Recently, both ATLAS and CMS collaborations at the CERN Large Hadron Collider (LHC) have announced their observations of an excess of diphoton events around the invariant mass of $750~{\rm GeV}$ with a local significance of $3.6\sigma$ and…
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750 GeV diphoton excess and its explanation in two-Higgs-doublet models with a real inert scalar multiplet Open
We discuss a possible explanation of the recently observed diphoton excess at\naround 750 GeV as seen by the ATLAS and CMS experiments at the Large Hadron\nCollider. We calculate the cross section of the diphoton signature in 2-Higgs\nDoub…
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(Higgs) vacuum decay during inflation Open
We develop the formalism for computing gravitational corrections to vacuum decay from de Sitter space as a sub-Planckian perturbative expansion. Non-minimal coupling to gravity can be encoded in an effective potential. The Coleman bounce c…
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Weak gravity conjecture, multiple point principle and the standard model landscape Open
The requirement for an ultraviolet completable theory to be well-behaved upon compactification has been suggested as a guiding principle for distinguishing the landscape from the swampland. Motivated by the weak gravity conjecture and the …
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Higgs naturalness and dark matter stability by scale invariance Open
Extending the spacetime symmetries of standard model (SM) by scale invariance (SI) may address the Higgs naturalness problem. In this article we attempt to embed accidental dark matter (DM) into SISM, requiring that the symmetry protecting…
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Local effects of the quantum vacuum in Lorentz-violating electrodynamics Open
The Casimir effect is one of the most remarkable consequences of the non-zero\nvacuum energy predicted by quantum field theory. In this paper we use a local\napproach to study the Lorentz violation effects of the minimal standard model\nex…
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Electroweak vacuum stability in classically conformal $$B-L$$ B - L extension of the standard model Open
Here, we consider the minimal U(1) B - L extension of the standard model (SM) with the classically conformal invariance, where an anomaly-free U(1) B - L gauge symme- try is introduced along with three generations of right-handed neutrin…
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Sphaleron and critical bubble in the scale invariant two Higgs doublet model Open
We revisit the electroweak phase transition and the critical bubble in the scale invariant two Higgs doublet model in the light of recent LHC data. Moreover, the sphaleron decoupling condition is newly evaluated in this model. The analysis…
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Type-II seesaw scalar triplet model at a 100 TeV pp collider: discovery and higgs portal coupling determination Open
We investigate the collider phenomenology of the scalar triplet particles in the Type-II seesaw model at a 100 TeV pp collider. Depending on triplet vacuum expectation value vΔ, the dominant discovery channels could be H++H-- and H±±H∓. We…
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Effect of a magnetic field on Schwinger mechanism in de Sitter spacetime Open
We investigate the effect of a constant magnetic field background on the scalar QED pair production in a four-dimensional de Sitter spacetime ($\dsf$). We have obtained the pair production rate which agrees with the known Schwinger result …
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Higgs relaxation after inflation Open
A bstract We show that the mechanism of cosmological relaxation of the electroweak scale can take place independently of the inflation mechanism, thus relieving burdens from the original relaxion proposal. What eventually stops the (fast-r…
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Vacuum fluctuations of a scalar field during inflation: Quantum versus stochastic analysis Open
We consider an infrared truncated massless minimally coupled scalar field\nwith a quartic self-interaction in the locally de Sitter background of an\ninflating universe. We compute the two-point correlation function of the scalar\nat one a…
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Sub-GeV dark matter model Open
We propose an extension of the Standard Model gauge symmetry by the gauge\ngroup $U(1)_{T3R}$ in order to address the Yukawa coupling hierarchy between\nthe third generation fermions and the first two generation fermions of the SM.\nWe ass…
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Flavored Peccei-Quinn symmetry Open
In an attempt to uncover any underlying physics in the standard model (SM),\nwe suggest a $\\mu$--$\\tau$ power law in the lepton sector, such that relatively\nlarge 13 mixing angle with bi-large ones can be derived. On the basis of this,\…
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Heavy Higgs boson decays in the alignment limit of the 2HDM Open
A bstract The Standard Model (SM)-like couplings of the observed Higgs boson impose strong constraints on the structure of any extended Higgs sector. We consider the theoretical properties and the phenomenological implications of a generic…
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Mini Review on Vector-Like Leptonic Dark Matter, Neutrino Mass, and Collider Signatures Open
We review a class of models in which the Standard Model (SM) is augmented by vector-like leptons: one doublet and a singlet, which are odd under an unbroken discrete Z2 symmetry. As a result, the neutral component of these additional vecto…
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Crunching Dilaton, Hidden Naturalness Open
We introduce a new approach to the Higgs naturalness problem. The Higgs mixes with the dilaton of a conformal field theory (CFT) sector whose true ground state has a large negative vacuum energy. If the Higgs vacuum expectation value is no…
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Vacuum stability and radiative electroweak symmetry breaking in an SO(10) dark matter model Open
Vacuum stability in the Standard Model is problematic as the Higgs quartic\nself-coupling runs negative at a renormalization scale of about $10^{10}$ GeV.\nWe consider a non-supersymmetric SO(10) grand unification model for which gauge\nco…
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Electroweak vacuum stability in presence of singlet scalar dark matter in TeV scale seesaw models Open
We consider singlet extensions of the standard model, both in the fermion and in the scalar sector, to account for the generation of neutrino mass at the TeV scale and the existence of dark matter, respectively. For the neutrino sector we …
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CP violating scalar Dark Matter Open
We study an extension of the Standard Model (SM) in which two copies of the SM scalar $SU(2)$ doublet which do not acquire a Vacuum Expectation Value (VEV), and hence are inert, are added to the scalar sector. We allow for CP-violation in …
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Leptogenesis via neutrino production during Higgs condensate relaxation Open
During inflation, scalar fields, including the Higgs boson, may acquire a\nnonzero vacuum expectation value, which must later relax to the equilibrium\nvalue during reheating. In the presence of the time-dependent condensate, the\nvacuum s…