Related papers: Updated limits on extra dimensions through torsion…
We study the effects of extra spacetime dimensions at intermediate mass scales, as expected in string theories with large-radius compactifications, and focus on the gauge and Yukawa couplings within the Minimal Supersymmetric Standard…
We analyze a two dimensional model of gauged fermions with quartic couplings in the large-N limit. This combines the 't Hooft model and the Gross-Neveu model where the coupling constants of both theories are arbitrary. Analytic equations…
Recently, a novel Einstein-Gauss-Bonnet gravity in four dimensions has been introduced [Phys. Rev. Lett. 124 (2020) 081301]. We will investigate cosmological consequences of this model in details. We will consider linear matter density…
In models with compact extra dimensions, where the Standard Model fields are confined to a 3+1 dimensional hyperplane, the $t \bar t$ production cross-section at a hadron collider can receive significant contributions from multiple exchange…
A contact four-fermion interaction between light quarks and electrons has been evoked as a possible explanation for the excess of events observed by HERA at high-$Q^2$. We explore the 1-loop effects of such interaction in $\Gamma(Z^0 \to…
The existence of bulk sterile neutrinos in theories with large extra dimensions can naturally explain small 4-dimensional Dirac masses for the active neutrinos. We study a model with 3 bulk neutrinos and derive various constraints on the…
Cold atom experiments can now realize mixtures where different components move in different spatial dimensions. We investigate a fermion mixture where one species is constrained to move along a one-dimensional lattice embedded in a…
We discuss how compactified extra dimensions may have potentially observable effects which grow as the compactification scale decreases. This arises because of lightcone fluctuations in the uncompactified dimensions which can result in the…
Higher-derivative terms in the string and M-theory effective actions are strongly constrained by supersymmetry. Using a mixture of techniques, involving both string amplitude calculations and an analysis of supersymmetry requirements, we…
We employ the techniques introduced in the companion papers to derive a connection formulation of Lorentzian General Relativity coupled to Dirac fermions in dimensions D+1 > 2 with compact gauge group. The technique that accomplishes that…
The effects of compact extra dimensions upon quantum stress tensor fluctuations are discussed. It is argued that as the compactification volume decrease, these fluctuations increase in magnitude. In principle, this would have the potential…
In this paper we argue the possibility that fermion masses, in particular quarks, originate through the condensation of a fourth family that interacts with all of the quarks via a contact four-fermion term coming from the existence of…
Axions arising as modes of higher-dimensional gauge fields are known to offer a compelling solution to the axion quality problem and to naturally arise in string theory. In this context, it is interesting to ask how we would interpret an…
We study the physics of a single discrete gravitational extra dimension using the effective field theory for massive gravitons. We first consider a minimal discretization with 4D gravitons on the sites and nearest neighbor hopping terms. At…
We briefly review the limits on new interactions implied by electroweak precision data. Special attention is payed to the bounds on the Higgs boson mass. We also comment on the required cancellation among the new contributions to precisely…
Multidimensional cosmological models with factorizable geometry and their dimensional reduction to effective four-dimensional theories are analyzed on sensitivity to different scalings. It is shown that a non-correct gauging of the…
A search is presented for extra spatial dimensions, quantum black holes, and quark contact interactions in measurements of dijet angular distributions in proton-proton collisions at sqrt(s) = 13 TeV. The data were collected with the CMS…
We discuss the possibility of explaining the excess in the cross section at high-Q^2 recently found at HERA in terms of four-fermion effective interactions. To avoid the constraints from low-energy data, we select three special cases in…
It is a challenge to explain why neutrinos are so light compared to other leptons. Small neutrino masses can be explained if right-handed fermions propagate in large extra dimensions. Fermions propagating in the bulk would have implications…
We investigate the collider implications of Split Universal Extra Dimensions. The non-vanishing fermion mass in the bulk, which is consistent with the KK-parity, largely modifies the phenomenology of Minimal Universal Exta Dimensions. We…