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We look for minimal extensions of Standard Model with vector like fermions leading to precision unification of gauge couplings. Constraints from proton decay, Higgs stability and perturbativity are considered. The simplest models contain…

High Energy Physics - Phenomenology · Physics 2018-05-17 Biplob Bhattacherjee , Pritibhajan Byakti , Ashwani Kushwaha , Sudhir K Vempati

Ultracold Fermi gases with tuneable interactions represent a unique test bed to explore the many-body physics of strongly interacting quantum systems. In the past decade, experiments have investigated a wealth of intriguing phenomena, and…

The aim of this thesis is to determine possible interactions between the Standard Model with right-chiral neutrinos and a sector of dark matter composed of a real scalar, left- and right-chiral fermion and a vector particle, which are…

High Energy Physics - Theory · Physics 2014-10-17 Mateusz Duch

We compute the exact induced parity-breaking part of the effective action for 2+1 massive fermions in $QED_3$ at finite temperature by calculating the fermion determinant in a particular background. The result confirms that gauge invariance…

High Energy Physics - Theory · Physics 2009-10-30 C. Fosco , G. L. Rossini , F. A. Schaposnik

We provide a unified and strengthened framework for the product form and the sum form variance-based uncertainty relations by constructing a unified uncertainty relation. In the unified framework, we deduce that the uncertainties of the…

Quantum Physics · Physics 2020-02-24 Xiao Zheng , Shao-Qiang Ma , Guo-Feng Zhang , Heng Fan , Wu-Ming Liu

In this article we discuss a general effective-theory description of a multi-component dark sector with an unspecified non-trivial symmetry and its interactions with the Standard Model generated by the exchange of heavy mediators. We then…

High Energy Physics - Phenomenology · Physics 2015-06-15 Vannia Gonzalez Macias , Jose Wudka

We consider the neutrino self-energy in a background composed of a scalar particle and a fermion using a simple model for the coupling of the form $\lambda\bar f_R\nu_L\phi$. The results are useful in the context of Dark Matter-neutrino…

High Energy Physics - Phenomenology · Physics 2022-01-17 José F. Nieves , Sarira Sahu

If leptonic unitarity is violated by new physics at an energy scale much lower than the electroweak scale, which we call low-scale unitarity violation, it has different characteristic features from those expected in unitarity violation at…

High Energy Physics - Phenomenology · Physics 2017-03-08 Chee Sheng Fong , Hisakazu Minakata , Hiroshi Nunokawa

With the LHC entering the precision era, focus on interpreting the measurements performed in an effective field theory holds key to testing the Standard Model. An effective field theory provides a well-defined theoretical formalism which…

Data Analysis, Statistics and Probability · Physics 2024-03-27 Rahul Balasubramanian , Lydia Brenner , Carsten Burgard , Wouter Verkerke

A general operator expansion is presented for quark and lepton mass matrices in unified theories based on a U(2) flavor symmetry, with breaking parameter of order $V_{cb} \approx m_s/m_b \approx \sqrt{m_c/m_t}$. While solving the…

High Energy Physics - Phenomenology · Physics 2009-10-30 R. Barbieri , L. J. Hall , S. Raby , A. Romanino

Supersymmetric lattice models of constrained fermions are known to feature exotic phenomena such as superfrustration, with an extensive degeneracy of ground states, the nature of which is however generally unknown. Here we address this…

Strongly Correlated Electrons · Physics 2021-09-22 Natalia Chepiga , Jiří Minář , Kareljan Schoutens

The celebrated antiferromagnetic phase transition was realized in a most recent optical lattice experiment for 3D fermionic Hubbard model [Shao {\it et al}., Nature {\bf 632}, 267 (2024)]. Despite the great achievement, it was observed that…

Strongly Correlated Electrons · Physics 2026-05-12 Yu-Feng Song , Youjin Deng , Yuan-Yao He

We derive perturbativity constraints on beyond standard model scenarios with extra gauge groups, such as $SU(2)$ or $U(1)$, whose generators contribute to the electric charge, and show that there are both upper and lower limits on the…

High Energy Physics - Phenomenology · Physics 2019-02-01 Garv Chauhan , P. S. Bhupal Dev , Rabindra N. Mohapatra , Yongchao Zhang

Dark photons are predicted by various new physics models, and are being intensively studied in a variety of experiments. In the first part of this paper, we obtain partial wave unitarity constraints on the dark photon parameter space from…

High Energy Physics - Phenomenology · Physics 2024-10-25 Yasaman Hosseini , Mojtaba Mohammadi Najafabadi

Unitarity relates the total cross section for neutrino-nucleon scattering to the neutrino-nucleon forward scattering amplitude. Assuming the validity of the perturbative expansion of the forward amplitude in the {\em weak} coupling…

High Energy Physics - Phenomenology · Physics 2009-11-07 Duane A. Dicus , Stefan Kretzer , Wayne W. Repko , Carl Schmidt

Effective field theories are an incredibly powerful tool in order to study and understand the true nature of the symmetry breaking sector dynamics of the Standard Model. However, they can suffer from some theoretical problems such as that…

High Energy Physics - Phenomenology · Physics 2019-11-19 C. Garcia-Garcia , M. J. Herrero , R. A. Morales

We develop, discuss, and compare several inference techniques to constrain theory parameters in collider experiments. By harnessing the latent-space structure of particle physics processes, we extract extra information from the simulator.…

High Energy Physics - Phenomenology · Physics 2018-09-19 Johann Brehmer , Kyle Cranmer , Gilles Louppe , Juan Pavez

In [Phys.Rev.Lett.92:162002 (2004), hep-lat/0312025] expressions for the continuous Euclidean time limits of various lattice fermion determinants were derived and compared in order to test universality expectations in Lattice QCD. Here we…

High Energy Physics - Lattice · Physics 2009-11-10 David H. Adams

A fundamental constant in systems of unitary fermions is the so-called Bertsch parameter, the ratio of the ground state energy for spin paired unitary fermions to that for free fermions at the same density. I discuss how we computed this…

High Energy Physics - Lattice · Physics 2011-06-30 Jong-Wan Lee , Michael G. Endres , David B. Kaplan , Amy N. Nicholson

The introduction of the infinite boundary terms and the pairwise interactions [J. Chem. Theory Comput., 10, 5254, (2014)] enables a physically intuitive approach for deriving electrostatic energy and pressure for both neutral and…

Computational Physics · Physics 2026-03-03 Yihao Zhao , Zhonghan Hu