arXiv subjects

Mukesh Kumar

Publications and source records attributed to Mukesh Kumar.

At least 19 recordsLinked to original sources

arXiv2026

Offline Nash Solvers Meet Online Tree Search in Multi-Agent Games on Graphs

Computing Nash equilibrium policies in multi-agent Pursuit-Evasion games (PEG) is challenging due to the exponential growth of the joint state and action spaces with the number of agents. Existing approaches either rely on offline equilibrium approximations, which may lack adaptability during execution, or online planning methods, which suffer from large branching factors. In this work, we propose Primitive-Guided Tree Search (PGTS), a hybrid framework that integrates offline exact Nash equilibrium computation with online tree search: PGTS first solves a collection of smaller, tractable sub-games offline; at deployment, PGTS performs online tree search at each time step, using the optimal sub-game policies and value functions to guide tree expansion and estimate leaf-node values. Extensive experiments on varied graph topologies, including real-world networks, demonstrate that PGTS significantly outperforms state-of-the-art learning and heuristic baselines, while maintaining robust performance against adversaries.

cs.GT↗

arXiv2026

Radiative Signature of New Scalar Boson Decays in the $m_{\ell \ell \gamma}$ Spectrum at the LHC

We investigate the radiative decay $S \to W^+W^-\gamma$ in the context of the multi-lepton anomalies and recent indications of a narrow scalar resonance near $m_S = 152 \pm 1~\text{GeV}$ in the $\gamma\gamma$, $Z\gamma$, and $W^+W^-$ channels at the Large Hadron Collider. These excesses arise in final states containing leptons, missing transverse momentum, and associated $b$-jets, and motivate a search for a corresponding localized excess in the invariant-mass spectrum of the dilepton--photon system, $m_{\ell\ell\gamma}$, in events with associated $b$-jets. We use recent CMS measurements of the ${t\bar{t}}\gamma$ differential cross sections~\cite{CMS:2025zbe} to study the $m_{\ell\ell\gamma}$ spectrum and perform a search for a scalar-resonance contribution. A localized excess is observed, compatible with the scalar-resonance hypothesis, with a global significance of $2.7\sigma$ at $m_S = 152~\text{GeV}$. This result provides additional support for the hypothesis of a narrow resonance. The ratio $\sigma(S \to W^+W^-\gamma)/\sigma(S \to W^+W^-) = (2.14 \pm 0.77)$\% is extracted. This value is compatible with an enhanced radiative contribution that could arise in scenarios beyond the Standard Model.

hep-ph↗

arXiv2026

Emerging Non-Volatile Opto-electronic Resistive Memories for Next-Generation Photonic Integrated Circuits

Photonic integrated circuits have emerged as a powerful platform for high speed communication, sensing, and information processing due to their large bandwidth, low latency, and inherent parallelism. However, the absence of efficient, scalable, and non-volatile memory elements remains a fundamental limitation for realizing fully programmable and adaptive photonic systems. Conventional electronic memories introduce significant energy overhead, latency, and architectural inefficiencies due to repeated optical electrical conversions. Non volatile opto electronic resistive memories or OERMs have recently emerged as a promising solution to address these challenges by integrating memory functionality directly within the photonic domain. These devices combine resistive switching mechanisms with optical readout, enabling persistent state retention, multilevel programmability, and energy efficient operation. In this review, we provide a comprehensive overview of OERMs, spanning from fundamental physical mechanisms to system level applications. We first discuss the underlying resistive switching phenomena, including filamentary conduction, interface type switching, phase change transitions, and ionic migration, with particular emphasis on their interaction with confined optical modes. We then examine key material platforms such as metal oxides, transparent conducting oxides, phase change materials, and emerging two-dimensional systems, highlighting their performance trade-offs. Furthermore, we analyse device architectures and benchmark their performance in terms of switching energy, speed, endurance, and optical modulation efficiency. The integration of OERMs into programmable photonic circuits, neuromorphic systems, and in-memory optical computing architectures is critically discussed. Finally, we outline the major challenges and future research directions toward scalable, reliable

physics.optics↗

arXiv2026

Multi-Lepton Probes of the Drell-Yan Production of Triplet Higgses

Excesses in di-photon, $Z\gamma$, and $WW$ spectra indicate the existence of a new Higgs boson with mass $152 \pm 1$ GeV. However, no excess is observed in the $ZZ$ channel. This pattern aligns with a Real Higgs Triplet model with hypercharge $Y = 0$ ($\Delta$SM). A prediction of this model is the Drell--Yan production of scalars at the LHC, which dominantly decay to electroweak bosons, thus enhancing the cross sections of triboson channels such as $WWZ$, $WZZ$, and $WWW$. Interestingly, both ATLAS and CMS have reported higher-than-expected significances for such processes: $6.4\sigma$ (observed) vs $4.7\sigma$ (expected) in the $VVZ$ (where $V = W$ or $Z$) channel and $4.4\sigma$ vs $3.6\sigma$ in $WWZ$, suggesting the possibility that these signals may be manifestations of an extended Higgs sector. We investigate whether the $\Delta$SM can account for these triboson excesses through electroweak production and decay of triplet scalars. We find that while current data prefers a non-zero new physics signal ($2.6\sigma$), the $\Delta$SM predicts more events than observed, such that it is consistent with data but not preferred over the SM. However, this tension could be clarified with Run~3 and HL-LHC data.

hep-ph↗

arXiv2026

Monochromatic Sums and Quotients Near Zero

Recently S. Goswami proved that whenever the set $\mathbb N$ of natural numbers is finitely colored, the set $\{a, b, ab, b(a+1)\}$ is monochromatic which also established a variant of the long-standing Hindman's conjecture, which asks for a monochromatic set of the form $\{a, b, ab, a+b\}$. Actually he disproved a conjecture proposed by J. Sahasrabudhe that $\{a, b, a(b + 1)\}$ is not partition regular. In this paper we prove that $\{a, b, ab, b(a+1)\}$ is monochromatic near zero which means for every finite coloring of a dense subsemigroups of $((0, \infty), +)$, the set $\{a, b, ab, b(a+1)\}$ is monochromatic near zero or in other words, we will get $a, b$ in a dense subsemigroups of $((0, \infty), +)$ as small as we want such that the set $\{a, b, ab, b(a+1)\}$ is monochromatic for every finite coloring of that dense subsemigroups of $((0, \infty), +)$, also we show that the pattern $x, y, x+y, \frac{y}{x}$ is partition regular near zero.

math.CO↗

arXiv2026

Heat Conduction and Energy Relaxation in an InAs Nanowire Approaching the Clean One-Dimensional Limit

We investigate heat conduction and energy relaxation in an InAs semiconductor nanowire using a hybrid semiconductor-superconductor architecture. Local electronic temperatures are measured with an in-situ grown quantum dot thermometer, while controlled Joule heating is applied at different locations along the wire to probe temperature gradients at sub-kelvin temperatures. With a onedimensional heat transport model, we calculate an electron-phonon heat flow that scales as Q_{e-ph} \propto T^2.6, which is in close agreement with the T^3 dependence predicted for a clean one-dimensional electron gas coupled to a phonon bath. We further estimate a characteristic length l_{eq} = 370 nm, beyond this length scale, phonon-mediated heat transport dominates over heat conduction in our nanowire. Our results provide a quantitative measure of energy relaxation mechanisms in a onedimensional semiconductor and provide a framework for studying heat flow in low-dimensional nanostructures.

cond-mat.mes-hall↗

arXiv2026

Fairness-Sensitive PageRank Approximation

Real-world social networks have structural inequalities, including the majority and minorities, and fairness-agnostic centrality measures often amplify these inequalities by disproportionately favoring majority nodes. Fairness-Sensitive PageRank aims to balance algorithmic influence across structurally and demographically diverse groups while preserving the link-based relevance of classical PageRank. However, existing formulations require solving constrained matrix inversions that scale poorly with network size. In this work, we develop an efficient mean-field approximation for Fairness-Sensitive PageRank (FSPR) that enforces group-level fairness through an estimated teleportation (jump) vector, thereby avoiding the costly matrix inversion and iterative optimization. We derive a closed-form approximation of FSPR using the in-degree and group label of nodes, along with the global group proportion. We further analyze intra-class fluctuations by deriving expressions for the variance of approximated FSPR scores. Empirical results on real-world networks demonstrate that the proposed approximation efficiently estimates the FSPR while reducing runtime by an order of magnitude, enabling fairness-constrained ranking at scale.

cs.SI↗

arXiv2025

Residential structure survivability to large wildfires in the United States

Wildfire impacts on US communities have escalated in recent decades, highlighting the need to better understand factors that influence wildfire outcomes. We find that 567,000 homes were exposed to wildfires across the contiguous US during 2001-2020, two-thirds of which occurred and increased five-fold in the Western US. While residential structure survivability - the percent of structures within a wildfire perimeter that survive the fire - remained stable in the Eastern US in the past two decades, it declined by 10% in the West. Survivability was explained by structural age, surrounding fuels, and fire weather. Survivability was 87% for homes built pre-1990 compared to 92% for post-1990 homes in the West. Survivability was lowest in forests compared to grasslands and shrublands. Finally, survivability was markedly lower for fires coincident with extreme fire weather. Our results suggest that modern building codes, fuel management, and proactive planning can strengthen wildfire resilience.

physics.ao-ph↗

arXiv2025

Emerging Narrow Resonance at 152 GeV

The discovery of the Higgs boson at the LHC completed the Standard Model (SM), yet the possibility of additional scalars remains open, provided their contributions to electroweak symmetry breaking are sufficiently small. Recent analyses of LHC data have revealed statistically significant anomalies in multi-lepton final states - events characterized by multiple leptons, missing transverse energy, and ($b$-)jets. These anomalies provide intriguing hints of physics beyond the SM. In this work, we present the signature of growing excesses for a new scalar resonance with a mass of $152 \pm 1$ GeV, observed in the $\gamma\gamma$, $Z\gamma$, and $WW$ channels. The combined global significance reaches a level that points toward the growing signature of this resonance. The findings align with a simplified model in which a heavy scalar boson decays into two lighter scalars, thus providing a consistent framework explaining the observed multi-lepton anomalies. These results significantly advance the search for new scalar bosons at the electroweak scale. Future investigations, including precision studies with upcoming HL-LHC data, will be crucial for confirming the nature of this resonance and exploring its implications for extending the SM.

hep-ph↗

arXiv2025

Exploring the Discovery Reach for a 95 GeV Scalar in Future $e^+e^-$ Collisions

The observed indications for a new scalar resonance with a mass around 95\,GeV, initially reported by LEP and supported by CMS and ATLAS in di-photon, $\tau \tau$, and $W^+ W^-$ channels, motivate exploring its discovery potential at future electron-positron colliders. This study focuses on the production of the new scalar ($S$) via $e^+ e^- \rightarrow ZS $ with $Z \rightarrow \mu^+ \mu^- $ and $S \rightarrow b \bar{b}$ and optimizes the signal recognition using the recoil-mass method. By employing deep neural networks for signal-background discrimination, we demonstrate that a 95\,GeV scalar, mixing with the Standard Model Higgs by an angle of $\sim$0.1, can be observed with a 5$\sigma$ significance at $\sqrt{s}$ = 250\,GeV or 200\,GeV with 5~ab$^{-1}$ of integrated luminosity.

hep-ph↗

arXiv2025

Discovery Prospects for the 150 GeV charged scalar at Future $e^+e^-$ Colliders

The Real Higgs Triplet model, known as the $\Delta$SM, is a minimal extension of the Standard Model (SM) obtained by adding a hypercharge 0 triplet ($\Delta$). This simple model is motivated by the multi-lepton anomalies and excesses in di-photon, $Z\gamma$, and $WW$ spectra at $\approx152$ GeV. The model contains, in addition to the SM particle content, a $CP$-even neutral Higgs ($\Delta^0$) and a charged state ($\Delta^\pm$), which are quasi-degenerate in mass. Observing the charged scalar at the LHC and measuring its mass is very challenging, since it dominantly decays to $WZ$, $tb$, and $\tau\nu$. In this article, we consider the discovery prospects of the charged Higgs with mass 150 GeV at future electron-positron colliders. Taking into account $e^+e^- \to \gamma^*,Z^* \to \Delta^\pm \Delta^\mp$ as the production mechanism and the dominant decay modes, we define three signal regions (SR) to study the 150 GeV charged Higgs properties: SR1: $\ge 3j + 1\ell$, SR2: $\ge 3\ell + \tau_{\text{had}}$, SR3: $\ge 4j + \tau_{\text{had}}$. For $m_{\Delta^\pm}=150\text{ GeV}$, a $5\sigma$ significance can be achieved in SR1 with an integrated luminosity of less than $1\text{ fb}^{-1}$. SR2 is very clean with leptonic final states having low background and small systematic uncertainties. Furthermore, SR3 is crucial for reconstructing the charged scalar invariant mass, which can be measured with $\mathcal{O}(1)$ GeV accuracy with an integrated luminosity of $500\text{ fb}^{-1}$.

hep-ph↗

arXiv2025

Phonon anomalies, Anharmonicity, and thermal expansion coefficient in few layered PtX2 (X= S, Se): A temperature dependent Raman study

Two-dimensional group-10 noble transition metal dichalcogenides have garnered growing attention due to their rich physical properties and promising applications across nanoelectronics, optoelectronics, and spintronics. Among them, PtX2 (X = S, Se) exhibits pronounced interlayer coupling driven by hybridization of the out-of-plane Pz orbitals of the chalcogen atoms. In this work, we present a detailed temperature and polarization-resolved Raman spectroscopic study of few-layer PtS2 and PtSe2 over the temperature range of ~ 5 to 300 K. Our study encompasses phonon-phonon interactions, symmetry analysis of phonon modes, low-frequency interlayer vibrations, and extraction of thermal expansion coefficients. Notable phonon anomalies in peak position, linewidth, and intensity emerge around ~ 80 K and 150 K for PtS2, and ~ 70 K and 240 K for PtSe2, indicating intricate coupling between thermal and vibrational dynamics. These results offer valuable insights for the development of devices based on PtS2, PtSe2, and related 2D materials, where interlayer interactions, anharmonic effects, and thermal expansion behaviour play crucial roles.

cond-mat.mtrl-sci↗

arXiv2025

Analyzing $t\bar{t}Z$-couplings at the future $e^-p$ collider

The proposed Large Hadron Electron Collider (LHeC), with center-of-mass energy of $\sqrt{s}\approx 1.3$ TeV, provides a clean and sensitive environment to probe the top quark's neutral current interactions with the $Z$ boson via the process $e^- p \to e^- t \bar{t}$. We investigate the precision with which the Standard Model (SM) $t\bar{t}Z$ couplings-the vector and axial-vector components ($\Delta C_{1V}$, $\Delta C_{1A}$)-can be measured, along with possible new physics effects parameterized by higher-dimensional operators inducing weak electric and magnetic dipole-like interactions ($C_{2V}$, $C_{2A}$). Focusing on the semileptonic decay channel, where either the top quark or anti-top decays leptonically to a positively charged lepton ($\ell^+ = e^+, \mu^+$), we utilize the azimuthal angle difference $\Delta \phi$ between the scattered electron and the charged lepton as the key observable. Using a one-parameter multi-bin $\chi^2$-analysis of this differential distribution, we find that constraints on $\Delta C_{1V}$ and $\Delta C_{1A}$ improve from order $10^{-1}$ at 50 fb$^{-1}$ to order $10^{-2}$ at 1000 fb$^{-1}$, corresponding to approximately 50% and 6% precision relative to their SM values. The anomalous tensor couplings $C_{2V}$ and $C_{2A}$ are constrained at the $10^{-1}$ level even at low luminosity and improve moderately with high luminosity. While the two-parameter analysis broadens the allowed regions due to parameter correlations, it retains competitive sensitivity, particularly for SM-like couplings. A systematic uncertainty of 5% is assumed throughout. These results highlight the LHeC's potential to provide complementary and competitive sensitivity to top-$Z$ couplings compared to current and future hadron and lepton collider capabilities.

hep-ph↗

arXiv2025

Comprehensive Constraints on ALP Couplings from future $e^+e^-$ Colliders, Muon $g-2$, Thermal Dark Matter and Higgs Measurements

In this article, we present projected 95\% C.L. limits on Axion-Like Particle (ALP) couplings from ALP production at a future $e^+e^-$ collider operating at $\sqrt{s} = 250~\text{GeV}$ with integrated luminosity $L = 0.5~\text{ab}^{-1}$. We constrain the effective couplings $g_{\gamma\gamma}$, $g_{Z\gamma}$, $g_{ZZ}$, and $g_{WW}$ over the ALP mass range $20~\text{GeV} \leq m_a \leq 100~\text{GeV}$, finding projected bounds at the level of $\mathcal{O}(10^{-1})~\text{TeV}^{-1}$ for $g_{\gamma\gamma}/f_a$. Given that the latest muon anomalous magnetic moment measurement ($\Delta a_\mu$) shows no statistically significant deviation from the Standard Model prediction, we reinterpret the ALP contributions to $\Delta a_\mu$ as a stringent consistency requirement. We then derive the corresponding allowed regions for $g_{\gamma\gamma}$ and the ALP--muon coupling $C_{\mu\mu}$, and apply them to a fermionic dark matter scenario in which the relic density depends on both the dark matter mass $m_\chi$ and $m_a$. The same parameter space is further constrained by Higgs signal strength measurements through $h \to \gamma\gamma$ and $h \to Z\gamma$. A comparative analysis with existing experimental and theoretical bounds highlights the complementarity of $\Delta a_\mu$, dark matter, and Higgs observables in restricting ALP couplings, demonstrating that even in the absence of a $\Delta a_\mu$ anomaly, these constraints provide essential guidance for viable ALP parameter space.

hep-ph↗

arXiv2025

Emerging Excess Consistent with a Narrow Resonance at 152 GeV in High-Energy Proton-Proton Collisions

The Higgs boson discovery at the Large Hadron Collider (LHC) at CERN confirmed the existence of the last missing particle of the Standard Model (SM). The existence of new fundamental constituents of matter beyond the SM is of great importance for our understanding of Nature. In this context, indirect (non-resonant) indications for new scalar bosons were found in the data from the first run of the LHC, taken between 2010 and 2012 at CERN: an excess in the invariant mass of muon-electron pairs, consistent with a new Higgs boson ($S$) with a mass of $150\pm5$ GeV. Other processes with multiple leptons in the final state, moderate missing energy, and possibly (bottom quark) jets exhibit deviations from the SM predictions. These anomalies can be explained within a simplified model in which a new heavy Higgs boson $H$ decays into two lighter Higgses $S$. This lighter Higgs $S$ subsequently decays to $W$ bosons, bottom quarks and has also an invisible decay mode. Here, we demonstrate that using this model we can identify narrow excesses in di-photon and $Z$-photon spectra around 152 GeV. By incorporating the latest measurements of di-photons in association with leptons, we obtain a combined global significance of $5.4\sigma$. This represents the highest significance ever reported for an excess consistent with a narrow resonance beyond the SM (BSM) in high-energy proton-proton collision data at the LHC. Such findings have the potential to usher in a new era in particle physics - the BSM epoch - offering crucial insights into unresolved puzzles of nature.

hep-ph↗

arXiv2025

The 4m International Liquid Mirror Telescope: Construction, operation, and science

The International Liquid Mirror Telescope (ILMT) project was motivated by the need for an inexpensive 4 metre diameter optical telescope that could be devoted entirely to astronomical surveys. Its scientific programmes include the detection and study of transients, variable objects, asteroids, comets, space debris and low surface brightness galaxies. To this end, a collaboration was formed between the Institute of Astrophysics and Geophysics (Li\`ege University, Belgium), several Canadian universities (University of British Columbia, Laval University, University of Montreal, University of Toronto, York University, University of Victoria) and the Aryabhatta Research Institute of Observational Sciences (ARIES, India). After several years of design work in Belgium and construction in India on the ARIES Devasthal site, the telescope saw its first light on 29 April 2022. Its commissioning phase lasted from May 2022 until June 2023 (beginning of the monsoon). The ILMT was inaugurated on 21 March 2023 and has been in regular operation since October 2023. The telescope continuously observes the sky passing at the zenith using the SDSS g', r', and i' filters. This paper describes the ILMT, its operation, performance and shows some initial results.

astro-ph.IM↗

arXiv2024

Optimizing Structured Data Processing through Robotic Process Automation

Robotic Process Automation (RPA) has emerged as a game-changing technology in data extraction, revolutionizing the way organizations process and analyze large volumes of documents such as invoices, purchase orders, and payment advices. This study investigates the use of RPA for structured data extraction and evaluates its advantages over manual processes. By comparing human-performed tasks with those executed by RPA software bots, we assess efficiency and accuracy in data extraction from invoices, focusing on the effectiveness of the RPA system. Through four distinct scenarios involving varying numbers of invoices, we measure efficiency in terms of time and effort required for task completion, as well as accuracy by comparing error rates between manual and RPA processes. Our findings highlight the significant efficiency gains achieved by RPA, with bots completing tasks in significantly less time compared to manual efforts across all cases. Moreover, the RPA system consistently achieves perfect accuracy, mitigating the risk of errors and enhancing process reliability. These results underscore the transformative potential of RPA in optimizing operational efficiency, reducing human labor costs, and improving overall business performance.

cs.AI↗

arXiv2024

Discovery Potential of Future Electron-Positron Colliders for a 95 GeV Scalar

The Large Electron Positron collider observed an indication for a new Higgs boson with a mass around $95$\,GeV-$100$\,GeV in the process $e^+e^-\to Z^*\to ZS$ with $S\to b\bar b$. The interest in this excess re-emerged with the di-photon signature at $\approx$\,95\,GeV at the Large Hadron Collider. In fact, a combined global significance of $3.4\sigma$ is obtained once $WW$ and $\tau\tau$ signals are included in addition. In this article, we perform a feasibility study for discovering such a new scalar $S$ at future electron-positron colliders using the recoil-mass method applied to $e^{+} e^{-} \to ZS$ with $Z \rightarrow \mu^{+} \mu^{-}$ and $S \to b \bar{b}$. For this, we employ a Deep Neural Network to enhance the separation between the Standard Model background and the signal, reducing the required integrated luminosity necessary for discovery by a factor of two to three. As a result, an $SU(2)_L$ singlet Higgs with a mass of $\approx$\,95\,GeV can be observed with more than 5$\sigma$ significance at a 250\,GeV centre-of-mass energy collider with $5~ {\rm ab}^{-1}$ integrated luminosity if it has a mixing angle of at least $0.1$ with the Standard Model Higgs, which means that a discovery can be achieved within the whole 95\% confidence-level region preferred by Large Electron Positron excess. Furthermore, including more decay channels such as $S\to \tau\tau$ and $Z\to e^+e^-$ further enhances the discovery potential of future $e^+e^-$ accelerators, like CEPC, CLIC, FCC-ee and ILC.

hep-ph↗