A5011856694- Galaxies: Formation, Evolution, Phenomena
- Scientific Research and Discoveries
- Cosmology and Gravitation Theories
- Stellar, planetary, and galactic studies
- Dark Matter and Cosmic Phenomena
- Astronomy and Astrophysical Research
- Computational Physics and Python Applications
- Radio Astronomy Observations and Technology
- Gamma-ray bursts and supernovae
- Astronomical Observations and Instrumentation
- Astrophysics and Cosmic Phenomena
- Astro and Planetary Science
- Cloud Computing and Resource Management
- Vehicle Dynamics and Control Systems
- Astrophysical Phenomena and Observations
- Superconducting and THz Device Technology
- Particle Accelerators and Free-Electron Lasers
- Spaceflight effects on biology
- Authorship Attribution and Profiling
- Blockchain Technology Applications and Security
- Distributed and Parallel Computing Systems
- Electric and Hybrid Vehicle Technologies
- Astrophysics and Star Formation Studies
- Data Visualization and Analytics
- Laser-Plasma Interactions and Diagnostics
University of Toledo
2022-2024
Columbia University
2019-2021
K J Somaiya Medical College
2018
Inter-University Centre for Astronomy and Astrophysics
2013
Fuzzy dark matter (FDM) or wave is an alternative theory designed to solve the small-scale problems faced by standard cold proposal for primary material component of universe. It made up ultra-light axions having mass $\sim 10^{-22}$ eV that typically have de Broglie wavelength several kpc, alleviating some apparent discrepancies $Λ$CDM paradigm. In this paper, we calculate halo function fuzzy using a sharp-k window and compare it with one calculated numerical simulations, finding peak at...
Abstract We train graph neural networks on halo catalogs from Gadget N -body simulations to perform field-level likelihood-free inference of cosmological parameters. The contain ≲5000 halos with masses ≳10 10 h −1 M ⊙ in a periodic volume <?CDATA ${(25\,{h}^{-1}\,\mathrm{Mpc})}^{3}$?> <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" overflow="scroll"> <mml:msup> <mml:mrow> <mml:mo stretchy="false">(</mml:mo> <mml:mn>25</mml:mn> <mml:mspace width="0.25em" /> <mml:mi>h</mml:mi>...
Population III stars are possible precursors to early massive and supermassive black holes (BHs). The presence of soft UV Lyman Werner (LW) background radiation can suppress star formation in minihalos allow them form pristine atomic cooling halos. In the absence molecular hydrogen ($\rm H_2$) cooling, atomic-cooling halos enable rapid collapse with suppressed fragmentation. High LW fluxes from preceding star-formation have been proposed dissociate $\rm H_2$. This flux be supplemented by one...
Abstract A key obstacle to accurate models of the first stars and galaxies is vast range distance scales that must be considered. While star formation occurs on sub-parsec within dark matter (DM) minihalos, it influenced by large-scale baryon-dark streaming velocities ( v bc ) Lyman-Werner (LW) radiative feedback which vary significantly ∼100 Mpc. We present a novel approach this issue in we utilize artificial neural networks (NNs) emulate Population III (PopIII) II (PopII) histories many...
Abstract We present a new self-consistent semianalytic model of the first stars and galaxies to explore high-redshift ( z ≥ 15) Population III (PopIII) metal-enriched star formation histories. Our includes detailed merger history dark matter halos generated with Monte Carlo trees. calibrate minimum halo mass for PopIII from recent hydrodynamical cosmological simulations that simultaneously include baryon–dark streaming velocity, Lyman–Werner (LW) feedback, molecular hydrogen self-shielding....
Abstract We discover analytic equations that can infer the value of Ω m from positions and velocity moduli halo galaxy catalogs. The are derived by combining a tailored graph neural network (GNN) architecture with symbolic regression. first train GNN on dark matter halos Gadget N -body simulations to perform field-level likelihood-free inference, show our model ∼6% accuracy catalogs thousands run six different codes: Abacus, CUBEP 3 M, Gadget, Enzo, PKDGrav3, Ramses. By applying regression...
Aims. We study the evolution of recurrent nova U Scorpii during its outburst in 2010.
Fuzzy dark matter (FDM) is a proposed modification for the standard cold (CDM) model motivated by small-scale discrepancies in low-mass galaxies. Composed of ultra-light (mass $\sim 10^{-22}$ eV) axions with kpc-scale de Broglie wavelengths, this one class candidates that predicts first collapsed objects form relatively massive halos. This implies formation history stars and galaxies would be very different, potentially placing strong constraints on such models. Here we numerically simulate...
Abstract Population III stars forming in minihalos tend to be relatively inefficient, with each minihalo hosting one or a small number of which are more massive than local stars, but still challenging observe directly at high redshift. Here we explore possible mechanism for the generation larger clusters such stars: nearby ionizing source that ionizes late halo, delaying its collapse until halo is sufficiently large enough core can self-shield and suffer runaway collapse. We use simulations...
In the financial systems of modern era, trust has always been a missing entity; concentrations power and have given birth to numerous breakdowns.To resolve problems at this end, paper attempts for solution using Blockchains, data structure that allows creation cryptically secured distributed tamperproof ledgers.The discusses further disserts on case study in consideration.
We discover analytic equations that can infer the value of $\Omega_{\rm m}$ from positions and velocity moduli halo galaxy catalogues. The are derived by combining a tailored graph neural network (GNN) architecture with symbolic regression. first train GNN on dark matter halos Gadget N-body simulations to perform field-level likelihood-free inference, show our model $\sim6\%$ accuracy catalogues thousands run six different codes: Abacus, CUBEP$^3$M, Gadget, Enzo, PKDGrav3, Ramses. By...
Abstract We present a method that calibrates semianalytic model to the Renaissance Simulations, suite of cosmological hydrodynamical simulations with high-redshift galaxy formation. This approach combines strengths techniques and simulations, enabling extension larger volumes lower redshifts are inaccessible due computational expense. Using sample star formation histories from an average density region Universe, we construct four-parameter prescription for metal-enriched characterized by...
We present a method that calibrates semi-analytic model to the Renaissance Simulations, suite of cosmological hydrodynamical simulations with high-redshift galaxy formation. This approach combines strengths techniques and simulations, enabling extension larger volumes lower redshifts inaccessible due computational expense. Using sample star formation histories (SFHs) from an average density region Universe, we construct four parameter prescription for metal-enriched characterized by initial...
A key obstacle to accurate models of the first stars and galaxies is vast range distance scales that must be considered. While star formation occurs on sub-parsec within dark matter (DM) minihalos, it influenced by large-scale baryon-dark streaming velocities ($v_{\rm bc}$) Lyman-Werner (LW) radiative feedback which vary significantly $\sim$100 Mpc. We present a novel approach this issue in we utilize artificial neural networks (NNs) emulate Population III (PopIII) II (PopII) histories many...
We present a new self-consistent semi-analytic model of the first stars and galaxies to explore high-redshift ($z{>}15$) Population III (PopIII) metal-enriched star formation histories. Our includes detailed merger history dark matter halos generated with Monte Carlo trees. calibrate minimum halo mass for PopIII from recent hydrodynamical cosmological simulations that simultaneously include baryon-dark streaming velocity, Lyman-Werner (LW) feedback, molecular hydrogen self-shielding. find an...
Abstract A critical dark matter halo mass ( M crit ) for Population III stars can be defined as the typical minimum that hosts sufficient cold-dense gas required formation of first stars. The presence Lyman–Werner (UV) radiation, which dissociate molecular hydrogen, and baryon-dark streaming velocity both delay by increasing . In this work, we constrain a function flux (including self-shielding), streaming, redshift using cosmological simulations with large sample halos utilizing adaptive...
We train graph neural networks on halo catalogues from Gadget N-body simulations to perform field-level likelihood-free inference of cosmological parameters. The contain $\lesssim$5,000 halos with masses $\gtrsim 10^{10}~h^{-1}M_\odot$ in a periodic volume $(25~h^{-1}{\rm Mpc})^3$; every the catalogue is characterized by several properties such as position, mass, velocity, concentration, and maximum circular velocity. Our models, built be permutationally, translationally, rotationally...
We carry out a comprehensive analysis of letter frequencies in contemporary written Marathi. determine sets letters which statistically predominate any large generic Marathi text, and use these to estimate the entropy
Fuzzy dark matter (FDM) is a proposed modification for the standard cold (CDM) model motivated by small-scale discrepancies in low-mass galaxies. Composed of ultra-light (mass $\sim 10^{-22}$ eV) axions with kpc-scale de Broglie wavelengths, this one class candidates that predicts first collapsed objects form relatively massive halos. This implies formation history stars and galaxies would be very different, potentially placing strong constraints on such models. Here we numerically simulate...