arXiv subjects

A. Karan

Publications and source records attributed to A. Karan.

2 recordsLinked to original sources

arXiv2025

Constraints on light scalars in the Aligned-two-Higgs-doublet model

In this work, we explore the viability of light-scalar scenarios within the $\mathcal{CP}$-conserving, flavour-aligned two-Higgs-doublet model (A2HDM), where at least one additional neutral or charged scalar is assumed to be lighter than the 125 GeV Higgs boson. The A2HDM naturally avoids flavour-changing neutral currents via Yukawa alignment, providing a more flexible framework than conventional $Z_2$-symmetric models. Employing the $\texttt{HEPfit}$ package within a Bayesian statistical approach, we perform global fits across all distinct light-scalar configurations, incorporating theoretical requirements and experimental constraints from electroweak precision observables, flavour data, Higgs measurements, and direct searches at the LEP and the LHC.

hep-ph↗

arXiv2016

The Hausdorff topology as a moduli space

In 1914, F. Hausdorff defined a metric on the set of closed subsets of a metric space $X$. This metric induces a topology on the set $H$ of compact subsets of $X$, called the Hausdorff topology. We show that the topological space $H$ represents the functor on the category of sequential topological spaces taking $T$ to the set of closed subspaces $Z$ of $T \times X$ for which the projection $π_1 : Z \to T$ is open and proper. In particular, the Hausdorff topology on $H$ depends on the metric space $X$ only through the underlying topological space of $X$. The Hausdorff space $H$ provides an analog of the Hilbert scheme in topology. As an example application, we explore a certain quotient construction, called the Hausdorff quotient, which is the analog of the Hilbert quotient in algebraic geometry.

math.AG↗