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We propose a supersymmetric composite model with three generations in which supersymmetry and electroweak symmetry are broken dynamically, and masses of quarks and leptons are generated without introducing any mass scales by hand. All the…

High Energy Physics - Phenomenology · Physics 2007-05-23 Noriaki Kitazawa

The LIGO/Virgo detections of gravitational waves from merging black holes of $\simeq$ 30 solar mass suggest progenitor stars of low metallicity (Z/Z$_{\odot} \lesssim 0.3$). In this talk I will provide constrains on where the progenitors of…

Astrophysics of Galaxies · Physics 2019-03-20 Astrid Lamberts

Structure formation provides a strong test of any cosmic acceleration model because a successful dark energy model must not inhibit {\black or overpredict} the development of observed large-scale structures. Traditional approaches to…

Cosmology and Nongalactic Astrophysics · Physics 2010-10-28 C. Prescod-Weinstein , N. Afshordi

Efficient algorithms for solving the Smallest Enclosing Sphere (SES) problem, such as Welzl's algorithm, often fail to handle degenerate subsets of points in 3D space. Degeneracies and ill-posed configurations present significant…

Computational Geometry · Computer Science 2024-12-16 Netzer Moriya

The role of major mergers in galaxy and black hole formation is not well constrained. To help address this, we develop an automated method to identify late-stage galaxy mergers before coalescence of the galactic cores. The resulting sample…

We introduce a general form of sequential Monte Carlo algorithm defined in terms of a parameterized resampling mechanism. We find that a suitably generalized notion of the Effective Sample Size (ESS), widely used to monitor algorithm…

Computation · Statistics 2016-01-08 Nick Whiteley , Anthony Lee , Kari Heine

Model merging combines fine-tuned checkpoints into a single multi-task model without retraining. Existing methods - such as task arithmetic, model soups, TIES, and DARE - are computationally efficient and empirically successful, but rely on…

Machine Learning · Computer Science 2026-05-29 Bethan Evans , Benjamin Etheridge , Stephen Roberts , Jared Tanner

In view of the forthcoming experiments at high energy $e^+ e^-$ colliders, LEP2 and beyond, the process $e^+ e^- \to W^+ W^- \to 4f$ has been investigated for {\it off-shell} $W$'s. After deriving the matrix element for the process within…

High Energy Physics - Phenomenology · Physics 2009-10-28 G. Montagna , O. Nicrosini , G. Passarino , F. Piccinini

Accurate modeling of galaxy formation in a hierarchical, cold dark matter universe requires the use of sufficiently high-resolution merger trees to obtain convergence in the predicted properties of galaxies. When semi-analytic galaxy…

Astrophysics of Galaxies · Physics 2016-08-17 Andrew J. Benson , Chris Cannella , Shaun Cole

We train a machine learning algorithm to learn cosmological structure formation from N-body simulations. The algorithm infers the relationship between the initial conditions and the final dark matter haloes, without the need to introduce…

Cosmology and Nongalactic Astrophysics · Physics 2018-07-02 Luisa Lucie-Smith , Hiranya V. Peiris , Andrew Pontzen , Michelle Lochner

We present a new collapse condition to describe the formation of dark halos via nonspherical gravitational clustering. This new nonspherical collapse condition is obtained by the logical generalization of the spherical model to the…

Astrophysics · Physics 2009-10-31 Tzihong Chiueh , Jounghun Lee

Hierarchical mergers of black holes are proposed as a mechanism to explain the observations of binary black holes with component masses between $\sim 50M_{\odot}\hbox{--}130M_{\odot}$ by LIGO/Virgo, often referred to as "upper mass gap". We…

High Energy Astrophysical Phenomena · Physics 2025-01-23 Parthapratim Mahapatra , Debatri Chattopadhyay , Anuradha Gupta , Marc Favata , B. S. Sathyaprakash , K. G. Arun

The claimed detection of large amounts of substructure in lensing flux anomalies, and in Milky Way stellar stream gaps statistics, has lead to a step change in constraints on simple warm dark matter models. In this study we compute…

Cosmology and Nongalactic Astrophysics · Physics 2020-08-20 M. R. Lovell

Probabilistic graphical models (PGMs) are powerful tools for solving systems of complex relationships over a variety of probability distributions. However, while tree-structured PGMs always result in efficient and exact solutions, inference…

Machine Learning · Computer Science 2021-11-10 Simon Streicher , Johan du Preez

We show that the discrepancy between the Tully-Fisher relation and the luminosity function predicted by most phenomenological galaxy formation models is mainly due to overmerging of galaxy haloes. We have circumvented this overmerging…

Astrophysics · Physics 2009-10-31 Eelco van Kampen , Raul Jimenez , John A. Peacock

We present a new semi-analytical model for the evolution of galaxies and supermassive black holes (SMBHs) that is based on the extended Press-Schechter formalism and phenomenological modelling of star formation. The model yields BH…

Cosmology and Nongalactic Astrophysics · Physics 2025-11-19 John Ellis , Malcolm Fairbairn , Juan Urrutia , Ville Vaskonen

In their third observing run, the LIGO-Virgo-KAGRA gravitational-wave (GW) observatory was sensitive to binary black hole (BBH) mergers out to redshifts $z_\mathrm{merge}\approx1$. Because GWs are inefficient at shrinking the binary orbit,…

Astrophysics of Galaxies · Physics 2023-11-17 Maya Fishbach , Lieke van Son

Numerous observations have shown that almost all galaxies in our Universe host supermassive black holes (SMBHs), but there is still much debate about their formation and evolutionary processes. Recently, gravitational waves (GWs) have been…

Cosmology and Nongalactic Astrophysics · Physics 2025-09-26 Kazuya Furusawa , Hiroyuki Tashiro , Shuichiro Yokoyama , Kiyotomo Ichiki

Markov chain Monte Carlo (MCMC) algorithms have become powerful tools for Bayesian inference. However, they do not scale well to large-data problems. Divide-and-conquer strategies, which split the data into batches and, for each batch, run…

Computation · Statistics 2017-07-18 Christopher Nemeth , Chris Sherlock

In the $\Lambda$CDM universe, structure formation is generally not a self-similar process, while some self-similarity remains in certain statistics which can greatly simplify our description and understanding of the cosmic structures. In…

Cosmology and Nongalactic Astrophysics · Physics 2025-06-12 Wenkang Jiang , Jiaxin Han , Fuyu Dong , Feihong He