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The Large Numbers Hypothesis: Outline of a Self-Similar Quantum
The Large Numbers Hypothesis: Outline of a self-similar quantum-cosmological Model H. GENREITH ∗ Institut f¨ur Geophysik und Meteorologie der Universit¨at zu K¨oln Abstract leads to a scaled quantum of action 3 In 1919 A. Einstein suspected first that gravita- H =Λ h (2) · tional fields could play an essential role in the in order to handle the Universe like an elementary structure of elementary particles. In 1937, P.A.M. particle. Hence the Universe should have an angu- Dirac found a miraculous link between the prop- lar momentum of about H/2π and it can be sus- erties of the visible Universe and elementary par- pected to be a huge rotating black-hole close to its ticles. Both conjectures stayed alive through the Kerr limit, or close to G¨odel’s spin [1, 2, 35, 10], following decades but still no final theory could be which is the value for the rotating cosmological so- derived to this issues. The herein suggested frac- lution to Einstein’s equations of General Relativity. tal model of the Universe gives a consistent expla- The recent discussion regarding the origin of and nation to Dirac’s Large Numbers Hypothesis and destiny of the Universe raises, for example, the combines the conjectures of Einstein and Dirac. question of where the Universe comes from. The main explanation for this is that time and space 1 Introduction were created with the big-bang and therefore the question of where the Universe is embedded or what 1.1 The Large Numbers Hypothesis happened before the creation, is not admissible. -
Searching for Diffuse Light in the M96 Group
Draft version June 30, 2016 Preprint typeset using LATEX style emulateapj v. 5/2/11 SEARCHING FOR DIFFUSE LIGHT IN THE M96 GALAXY GROUP Aaron E. Watkins1, J. Christopher Mihos1,Paul Harding1,John J. Feldmeier2 Draft version June 30, 2016 ABSTRACT We present deep, wide-field imaging of the M96 galaxy group (also known as the Leo I Group). Down to surface brightness limits of µB = 30:1 and µV = 29:5, we find no diffuse, large-scale optical counterpart to the “Leo Ring”, an extended HI ring surrounding the central elliptical M105 (NGC 3379). However, we do find a number of extremely low surface-brightness (µB & 29) small-scale streamlike features, possibly tidal in origin, two of which may be associated with the Ring. In addition we present detailed surface photometry of each of the group’s most massive members – M105, NGC 3384, M96 (NGC 3368), and M95 (NGC 3351) – out to large radius and low surface brightness, where we search for signatures of interaction and accretion events. We find that the outer isophotes of both M105 and M95 appear almost completely undisturbed, in contrast to NGC 3384 which shows a system of diffuse shells indicative of a recent minor merger. We also find photometric evidence that M96 is accreting gas from the HI ring, in agreement with HI data. In general, however, interaction signatures in the M96 Group are extremely subtle for a group environment, and provide some tension with interaction scenarios for the formation of the Leo HI Ring. The lack of a significant component of diffuse intragroup starlight in the M96 Group is consistent with its status as a loose galaxy group in which encounters are relatively mild and infrequent. -
What Is Gravity and How Is Embedded in Mater Particles Giving Them Mass (Not the Higgs Field)? Stefan Mehedinteanu
What Is Gravity and How Is Embedded in Mater Particles giving them mass (not the Higgs field)? Stefan Mehedinteanu To cite this version: Stefan Mehedinteanu. What Is Gravity and How Is Embedded in Mater Particles giving them mass (not the Higgs field)?. 2017. hal-01316929v6 HAL Id: hal-01316929 https://hal.archives-ouvertes.fr/hal-01316929v6 Preprint submitted on 23 Feb 2017 HAL is a multi-disciplinary open access L’archive ouverte pluridisciplinaire HAL, est archive for the deposit and dissemination of sci- destinée au dépôt et à la diffusion de documents entific research documents, whether they are pub- scientifiques de niveau recherche, publiés ou non, lished or not. The documents may come from émanant des établissements d’enseignement et de teaching and research institutions in France or recherche français ou étrangers, des laboratoires abroad, or from public or private research centers. publics ou privés. Distributed under a Creative Commons Attribution| 4.0 International License What Is Gravity (Graviton) and How Is Embedded in Mater Particles Giving Them Mass (Not the Higgs Field)? Stefan Mehedinteanu1 1 (retired) Senior Researcher CITON-Romania; E-Mail: [email protected]; [email protected] “When Einstein was asked bout the discovery of new particles, the answer it was: firstly to clarify what is with the electron!” Abstract It will be shown how the Micro-black-holes particles produced at the horizon entry into a number of N 106162 by quantum fluctuation as virtual micro-black holes pairs like e+ e- creation, stay at the base of: the origin and evolution of Universe, the Black Holes (BH) nuclei of galaxies, of the free photons creation of near mass-less as by radiation decay that condensate later at Confinement in to the structure of gauge bosons (gluons) . -
ALFALFA Survey of the Leo Region S
ALFALFA Survey of the Leo Region S. Stierwalt, M.P. Haynes, R. Giovanelli, B. Kent, A. Saintonge (Cornell University), I.D. Karachentsev (Russian Academy of Sciences), V.E. Karachentseva (Astronomical Observatory of Kiev), N. Brosch (Wise Observatory), L. Hoffman (Lafayette College), B.Catinella, E. Momjian (Arecibo Observatory) ABSTRACT: The Leo region offers a detailed view of several nearby groups Points of Interest in the Leo Region of galaxies including Leo I at 10.4 Mpc and another slightly more distant (10h30m<RA<11h30m, 8º<dec<16º) structure within the Local Supercluster (Leo II). Leo I is of particular interest because it contains both a large ring of intergalactic gas of unknown origin (the Leo Ring) as well as a long tidal stream of stars and gas in the Leo Triplet. Because of its proximity, Leo can also offer insight M66 into the nature of low-mass, low-surface brightness galaxies believed to be the building blocks of galaxy formation. A direct comparison of optically and HI selected samples of dwarf galaxy candidates in the region has been made. This work has been supported by NSF grants AST-0307661 and AST--0435697 & by the Brinson Foundation. NNGGCC 3 6326828 OPTICALLY-SELECTED SAMPLE: Dwarf galaxy candidates in the Leo region were optically selected via a visual inspection of POSS-II/ESO/Serc plates by Karachentsev and Karachentseva. Sensitive, targeted single-pixel Arecibo Leo Ring of M65 gas in M96 group observations were taken of those candidates. Twenty-one of a possible thirty- Leo Triplet (Image from five dwarf galaxies were detected in HI including five background sources. -
Cosmological Matter-Antimatter Asymmetry and Antimatter in the Universe
View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by CERN Document Server COSMOLOGICAL MATTER-ANTIMATTER ASYMMETRY AND ANTIMATTER IN THE UNIVERSE A.D. DOLGOV INFN, sezione di Ferrara, Via Paradiso, 12 - 44100 Ferrara, Italy and ITEP, Bol. Cheremushkinskaya 25, Moscow 113259, Russia Models of baryogenesis which may lead to astronomically significant amount of antimatter in the universe are reviewed. Observational features are briefly discussed. 1 Introduction Prediction of antimatter by Dirac 1 (1928) and quick subsequent discovery of the first antimatter particle, positron, by Anderson 2 (1933) are among greatest scientific achievements of XX cen- tury. Discovery of antiproton 22 years later 3 was the next step which had opened a whole new world of antiparticles. Now for (almost) every elementary particle a corresponding antiparticle has also been observed. The latter have opposite signs of all associated charges and, according to CPT theorem4, the same masses and, if unstable, life-times. Such symmetry between par- ticles and antiparticles naturally leads to suggestion that the universe as a whole may be also symmetric with respect to transformation from particles to antiparticles and there should exist astronomically large regions consisting of antimatter: anti-stars, clouds of diffuse antimatter, whole anti-galaxies, or even large clusters of anti-galaxies. As Dirac 5 said in his Nobel lecture a: “... we must regard it rather as an accident that the Earth (and presumably the whole solar system), contains a preponderance of negative electrons and positive protons. It is quite possible that for some of the stars it is the other way about, these stars being built up mainly of positrons and negative protons. -
A STUDY of DWARF GALAXIES EMBEDDED in a LARGE-SCALE H I RING in the LEO I GROUP a Large-Scale Neutral Hydrogen (H I) Ring Serend
Publications of the Korean Astronomical Society pISSN: 1225-1534 30: 517 ∼ 519, 2015 September eISSN: 2287-6936 c 2015. The Korean Astronomical Society. All rights reserved. http://dx.doi.org/10.5303/PKAS.2015.30.2.517 A STUDY OF DWARF GALAXIES EMBEDDED IN A LARGE-SCALE H i RING IN THE LEO I GROUP Myo Jin Kim1, Aeree Chung y1, Jong Chul Lee2, Sungsoon Lim3, Minjin Kim2,5, Jongwan Ko2, Joon Hyeop Lee2,5, Soung-Chul Yang2,4, and Hye-Ran Lee2,5 1Department of Astronomy, Yonsei University, 50 Yonsei-ro, Seodaemun-gu, Seoul 120-749, Korea 2Korea Astronomy and Space Science Institute, 776 Daedeok-daero, Yuseong-gu, Daejeon 305-348, Korea 3Peking University, No.5 Yiheyuan Road, Haidian District, Beijing, China 4The Observatories of the Carnegie Institution for Science, 813 Santa Barbara Street, Pasadena, California, USA 5Korea University of Science and Technology, 217 Gajeong-ro, Yuseong-gu, Daejeon 305-350, Korea E-mail: [email protected], [email protected] (Received November 30, 2014; Reviced May 31, 2015; Aaccepted June 30, 2015) ABSTRACT A large-scale neutral hydrogen (H i) ring serendipitously found in the Leo I galaxy group is 200 kpc 9 in diameter with MH i ∼ 1:67 × 10 M , unique in size in the Local Universe. It is still under debate where this H i ring originated - whether it has formed out of the gas remaining after the formation of a galaxy group (primordial origin) or been stripped during galaxy-galaxy interactions (tidal origin). We are investigating the optical and H i gas properties of the dwarf galaxies located within the gas ring in order to probe its formation mechanism. -
Curriculum Vitae: M. Coleman Miller Date of Birth
Curriculum Vitae: M. Coleman Miller Date of Birth: 6 July 1968 The University of Maryland Place of Birth: Detroit, MI Department of Astronomy Citizenship: USA College Park, MD 20742-2421 E-mail: [email protected] Telephone: (301) 405-1037 FAX: (301) 314-9067 Webpage: http://www.astro.umd.edu/∼miller/ Research Interests Theoretical Astrophysics Computer Simulations and Modeling Physics of Dense Matter Physics in Strong Magnetic Fields General Relativity Gravitational Radiation PlasmaPhysics GravitationalLensing Education 1984 - 1990 California Institute of Technology, Pasadena, California Department: Physics, with Computer Science minor Thesis Topic: Radiation Transfer in Very Strong Magnetic Fields Degrees: M.S. (1986), Ph.D. (1990) (Advisor: E. S. Phinney) National Science Foundation Graduate Fellow, 1984-1987 1980 - 1984 Hillsdale College, Hillsdale, Michigan Major fields: Mathematics and Physics Degree: B.S., Summa Cum Laude (1984) Research Experience 2009 - Professor of Astronomy, University of Maryland 2020 Radboud Excellence Professor, Radboud University, Nijmegen, Netherlands 2017 - 2019 Chair, Maryland Astronomy Center for Theory and Computation 2015 - 2019 Astronomy Director, Joint Space-Science Institute 2013 - 2014 Director, Joint Space-Science Institute 2004 - 2009 Associate Professor of Astronomy, University of Maryland 2004 - 2006 Chair, Maryland Astronomy Center for Theory and Computation 1999 - 2004 Assistant Professor of Astronomy, University of Maryland 1997 - 1999 Member of the AXAF Science Center, Chicago beta test site 1994 - 1997 Compton Gamma-Ray Observatory Fellow, University of Chicago 1993 - 1999 Research Scientist, University of Chicago Constructed the first detailed model of kilohertz QPOs of neutron star low-mass X- ray binaries, investigated gravitational lensing of gamma-ray bursts and galaxies, and performed various studies of accreting black holes and neutron stars. -
Grand Unified Theories - Ii
- 31 - GRAND UNIFIED THEORIES - II J. Ellis CERN, Geneva, Switzerland INTRODUCTION In the previous lectures1»2) you have seen how the inadequacies of the standard SU(3) x SU(2) x U(l) model of the strong, weak, and electromagnetic interactions motivate the construction of grand unified theories (GUTs) which are sketched in Fig. 1. The strategy- then adopted was to assign the fundamental fermions — quarks and leptons — to "generations" forming economical representations of a simple grand unifying group G. The observed dis• parity of the strong and weak coupling constants implies that the group G must be broken down at a very high energy scale. The properties of the running coupling constants in re- normalizable field theories enable one to estimate3) this breaking scale to be around 1015 GeV in simple models'*) such as SU(5). Although the grand unification symmetry is very strongly broken, it can still be used to make predictions for parameters observable at low energies. In addition to the quantization of electromagnetic charge (|Q_|/|Q | = 1) which ^e p flows from the embedding of electromagnetic U(l) into a simple group, it is possible to 2 make predictions for the neutral weak mixing parameter sin 6W and for the ratios of certain 2 quark and lepton masses. While the predictions for sin 9W and m^/m^. are spectacularly successful, there are clouds over the predictions for the masses of other quarks1»2). The real tests of GUTs lie, however, with their predictions for new interactions, which can lead to qualitatively new phenomena such as baryon decay or neutrino masses and oscilla• tions. -
Black Hole Entropy Entanglement And
BLACK HOLE ENTROPY ! ENTANGLEMENT! AND! HOLOGRAPHIC SPACETIME" Ted Jacobson" University of Maryland" Goddard Scientific Colloquium, Feb. 7, 2018 Holographic " Information" principle" paradox" Area 3 4~GN /c geometry" black hole " Einstein eqn " from" entropy" as vacuum " entanglement " thermodynamics" QFT " renormalization" Albert Einstein, aged 33, 1912" GRAVITY IS CURVATURE OF SPACETIME" Spatial curvature analogy:" " Spacetime" Initially parallel lines " don’t stay parallel" time" earth" apple" Time runs slower lower down!" B" Apple free-fall " apple" is the straightest path " in spacetime between A & B…" and the path of longest time." How much slower? " One billionth of a second per year per foot" A" ’ 2 earth" at the earth s surface (g/c )." Spiral of Mercury’s orbit: didn’t fit Newton’s theory, " by 43’’/century…" That’s about 9 minutes advance time for the transit per century… " General relativity nailed it." To calculate the rate of perihelion advance Einstein needed only the first approximation to the line element outside the sun: " " 2 2 2 2 2 2 2 ds = (1− rS r)dt − (1+ rS r)dr − r (dθ +sin θ dϕ ) 2 rS = 2GM c = 3km The Schwarzschild Singularity (1916) 2 2 −1 2 2 2 2 2 ds = (1− rS r)dt − (1− rS r) dr − r (dθ +sin θ dϕ ) 2 rS = 2GM c = 3km "Schwarzschild radius" Schwarzschild (1916): “in order that this discontinuity coincides with the origin” one should define the radial coordinate appropriately. Droste (1916): “a moving particle can never pass that sphere because it would take an infinite amount of time” The true, non-singular nature of the Schwarzschild “singularity” was not widely understood until 42 years later… but it was understood perfectly well by one man in 1932… Georges Lemaitre First person to understand the nature of the Schwarzschild singularity as an event horizon (1932). -
April 2016 BRAS Newsletter
April 2016 Issue th Next Meeting: Monday, April 11 at 7PM at HRPO (2nd Mondays, Highland Road Park Observatory) April 6th through April 10th is our annual Hodges Gardens Star Party. You can pre-register using the form on the BRAS website. If you have never attended this star party, make plans to attend this one. What's In This Issue? President’s Message Photos: BRAS Telescope donated to EBRP Library Secretary's Summary of March Meeting Recent BRAS Forum Entries 20/20 Vision Campaign Message from the HRPO Astro Short: Stellar Dinosaurs? International Astronomy Day Observing Notes: Leo The Lion, by John Nagle Newsletter of the Baton Rouge Astronomical Society April 2016 Page 2 President’s Message There were 478 people who stopped by the BRAS display at the March 19th ―Rockin at the Swamp‖ event at the Bluebonnet Swamp and Nature Center. I give thanks to all our volunteers for our success in this outreach event. April 6th through April 10th is our annual Hodges Gardens Star Party. You can pre-register on the BRAS website, or register when you arrive (directions are on the BRAS website). If you have never attended a star party, of if you are an old veteran star partier; make plans to attend this one. Our Guest Speaker for the BRAS meeting on April 11th will be Dr. Joseph Giaime, Observatory Head, LIGO Livingston (Caltech), Professor of Physics and Astronomy (LSU). Yes, he will be talking about gravity waves and the extraordinary discovery LIGO has made. We need volunteers to help at our display on Earth Day on Sunday, April 17th. -
Gaseous Nebulae and Massive Stars in the Giant HI Ring In
Astronomy & Astrophysics manuscript no. astroph_leoring ©ESO 2021 April 16, 2021 Gaseous nebulae and massive stars in the giant H i ring in Leo Edvige Corbelli1, Filippo Mannucci1, David Thilker2, Giovanni Cresci1, and Giacomo Venturi3; 1 1 INAF-Osservatorio di Arcetri, Largo E. Fermi 5, 50125 Firenze, Italy e-mail: [email protected] 2 Department of Physics and Astronomy, The Johns Hopkins University, Baltimore, MD, USA 3 Instituto de Astrofísica, Facultad de Física, Pontificia Universidad Católica de Chile, Casilla 306, Santiago 22, Chile Received ....; accepted ...... ABSTRACT Context. Chemical abundances in the Leo ring, the largest H i cloud in the local Universe, have recently been determined to be close or above solar (Corbelli et al. 2021), incompatible with a previously claimed primordial origin of the ring. The gas, pre-enriched in a galactic disk and tidally stripped, did not manage to form stars very efficiently in intergalactic space. Aims. Using Hα emission and a multi wavelengths analysis of its extremely faint optical counterpart we investigate the process of star formation and the slow building up of a stellar population. Methods. We map nebular lines in 3 dense H i clumps of the Leo ring and complement these data with archival stellar continuum observations and population synthesis models. Results. A sparse population of stars is detected in the main body of the ring, with individual young stars as massive as O7-types −5 −1 −2 powering some H ii region. The average star formation rate density in the ring is of order of 10 M yr kpc and proceeds with local bursts a few hundred parsecs in size, where loose stellar associations of 500 – 1000 M occasionally host massive outliers. -
Neutrino Decoherence from Quantum Gravitational Stochastic Perturbations
Neutrino decoherence from quantum gravitational stochastic perturbations Stuttard, Thomas; Jensen, Mikkel Published in: Physical Review D DOI: 10.1103/PhysRevD.102.115003 Publication date: 2020 Document version Publisher's PDF, also known as Version of record Document license: CC BY Citation for published version (APA): Stuttard, T., & Jensen, M. (2020). Neutrino decoherence from quantum gravitational stochastic perturbations. Physical Review D, 102(11), [115003]. https://doi.org/10.1103/PhysRevD.102.115003 Download date: 30. sep.. 2021 PHYSICAL REVIEW D 102, 115003 (2020) Neutrino decoherence from quantum gravitational stochastic perturbations Thomas Stuttard and Mikkel Jensen Niels Bohr Institute, University of Copenhagen, DK-2100 Copenhagen, Denmark (Received 9 July 2020; accepted 30 October 2020; published 1 December 2020) Neutrinos undergoing stochastic perturbations as they propagate experience decoherence, damping neutrino oscillations over distance. Such perturbations may result from fluctuations in space-time itself if gravity is a quantum force, including interactions between neutrinos and virtual black holes. In this work we model the influence of heuristic neutrino-virtual black hole interaction scenarios on neutrino propagation and evaluate the resulting signals in astrophysical and atmospheric neutrinos. We derive decoherence operators representing these effects in the framework of open quantum systems, allowing experimental constraints on such systems to be connected to quantum gravitational effects. Finally, we consider