Introduction to Cosmology and Dark Matter
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The Universe, Life and Everything…
Our current understanding of our world is nearly 350 years old. Durston It stems from the ideas of Descartes and Newton and has brought us many great things, including modern science and & increases in wealth, health and everyday living standards. Baggerman Furthermore, it is so engrained in our daily lives that we have forgotten it is a paradigm, not fact. However, there are some problems with it: first, there is no satisfactory explanation for why we have consciousness and experience meaning in our The lives. Second, modern-day physics tells us that observations Universe, depend on characteristics of the observer at the large, cosmic Dialogues on and small, subatomic scales. Third, the ongoing humanitarian and environmental crises show us that our world is vastly The interconnected. Our understanding of reality is expanding to Universe, incorporate these issues. In The Universe, Life and Everything... our Changing Dialogues on our Changing Understanding of Reality, some of the scholars at the forefront of this change discuss the direction it is taking and its urgency. Life Understanding Life and and Sarah Durston is Professor of Developmental Disorders of the Brain at the University Medical Centre Utrecht, and was at the Everything of Reality Netherlands Institute for Advanced Study in 2016/2017. Ton Baggerman is an economic psychologist and psychotherapist in Tilburg. Everything ISBN978-94-629-8740-1 AUP.nl 9789462 987401 Sarah Durston and Ton Baggerman The Universe, Life and Everything… The Universe, Life and Everything… Dialogues on our Changing Understanding of Reality Sarah Durston and Ton Baggerman AUP Contact information for authors Sarah Durston: [email protected] Ton Baggerman: [email protected] Cover design: Suzan Beijer grafisch ontwerp, Amersfoort Lay-out: Crius Group, Hulshout Amsterdam University Press English-language titles are distributed in the US and Canada by the University of Chicago Press. -
Science in Nasa's Vision for Space Exploration
SCIENCE IN NASA’S VISION FOR SPACE EXPLORATION SCIENCE IN NASA’S VISION FOR SPACE EXPLORATION Committee on the Scientific Context for Space Exploration Space Studies Board Division on Engineering and Physical Sciences THE NATIONAL ACADEMIES PRESS Washington, D.C. www.nap.edu THE NATIONAL ACADEMIES PRESS 500 Fifth Street, N.W. Washington, DC 20001 NOTICE: The project that is the subject of this report was approved by the Governing Board of the National Research Council, whose members are drawn from the councils of the National Academy of Sciences, the National Academy of Engineering, and the Institute of Medicine. The members of the committee responsible for the report were chosen for their special competences and with regard for appropriate balance. Support for this project was provided by Contract NASW 01001 between the National Academy of Sciences and the National Aeronautics and Space Administration. Any opinions, findings, conclusions, or recommendations expressed in this material are those of the authors and do not necessarily reflect the views of the sponsors. International Standard Book Number 0-309-09593-X (Book) International Standard Book Number 0-309-54880-2 (PDF) Copies of this report are available free of charge from Space Studies Board National Research Council The Keck Center of the National Academies 500 Fifth Street, N.W. Washington, DC 20001 Additional copies of this report are available from the National Academies Press, 500 Fifth Street, N.W., Lockbox 285, Washington, DC 20055; (800) 624-6242 or (202) 334-3313 (in the Washington metropolitan area); Internet, http://www.nap.edu. Copyright 2005 by the National Academy of Sciences. -
Adrien Christian René THOB
THE RELATIONSHIP BETWEEN THE MORPHOLOGY AND KINEMATICS OF GALAXIES AND ITS DEPENDENCE ON DARK MATTER HALO STRUCTURE IN SIMULATED GALAXIES Adrien Christian René THOB A thesis submitted in partial fulfilment of the requirements of Liverpool John Moores University for the degree of Doctor of Philosophy. 26 April 2019 To my grand-parents, René Roumeaux, Christian Thob, Yvette Roumeaux (née Bajaud) and Anne-Marie Thob (née Léglise). ii Abstract Galaxies are among nature’s most majestic and diverse structures. They can play host to as few as several thousands of stars, or as many as hundreds of billions. They exhibit a broad range of shapes, sizes, colours, and they can inhabit vastly differing cosmic environments. The physics of galaxy formation is highly non-linear and in- volves a variety of physical mechanisms, precluding the development of entirely an- alytic descriptions, thus requiring that theoretical ideas concerning the origin of this diversity are tested via the confrontation of numerical models (or “simulations”) with observational measurements. The EAGLE project (which stands for Evolution and Assembly of GaLaxies and their Environments) is a state-of-the-art suite of such cos- mological hydrodynamical simulations of the Universe. EAGLE is unique in that the ill-understood efficiencies of feedback mechanisms implemented in the model were calibrated to ensure that the observed stellar masses and sizes of present-day galaxies were reproduced. We investigate the connection between the morphology and internal 9:5 kinematics of the stellar component of central galaxies with mass M? > 10 M in the EAGLE simulations. We compare several kinematic diagnostics commonly used to describe simulated galaxies, and find good consistency between them. -
Dark Energy and Dark Matter
Dark Energy and Dark Matter Jeevan Regmi Department of Physics, Prithvi Narayan Campus, Pokhara [email protected] Abstract: The new discoveries and evidences in the field of astrophysics have explored new area of discussion each day. It provides an inspiration for the search of new laws and symmetries in nature. One of the interesting issues of the decade is the accelerating universe. Though much is known about universe, still a lot of mysteries are present about it. The new concepts of dark energy and dark matter are being explained to answer the mysterious facts. However it unfolds the rays of hope for solving the various properties and dimensions of space. Keywords: dark energy, dark matter, accelerating universe, space-time curvature, cosmological constant, gravitational lensing. 1. INTRODUCTION observations. Precision measurements of the cosmic It was Albert Einstein first to realize that empty microwave background (CMB) have shown that the space is not 'nothing'. Space has amazing properties. total energy density of the universe is very near the Many of which are just beginning to be understood. critical density needed to make the universe flat The first property that Einstein discovered is that it is (i.e. the curvature of space-time, defined in General possible for more space to come into existence. And Relativity, goes to zero on large scales). Since energy his cosmological constant makes a prediction that is equivalent to mass (Special Relativity: E = mc2), empty space can possess its own energy. Theorists this is usually expressed in terms of a critical mass still don't have correct explanation for this but they density needed to make the universe flat. -
Illumination and Distance
PHYS 1400: Physical Science Laboratory Manual ILLUMINATION AND DISTANCE INTRODUCTION How bright is that light? You know, from experience, that a 100W light bulb is brighter than a 60W bulb. The wattage measures the energy used by the bulb, which depends on the bulb, not on where the person observing it is located. But you also know that how bright the light looks does depend on how far away it is. That 100W bulb is still emitting the same amount of energy every second, but if you are farther away from it, the energy is spread out over a greater area. You receive less energy, and perceive the light as less bright. But because the light energy is spread out over an area, it’s not a linear relationship. When you double the distance, the energy is spread out over four times as much area. If you triple the distance, the area is nine Twice the distance, ¼ as bright. Triple the distance? 11% as bright. times as great, meaning that you receive only 1/9 (or 11%) as much energy from the light source. To quantify the amount of light, we will use units called lux. The idea is simple: energy emitted per second (Watts), spread out over an area (square meters). However, a lux is not a W/m2! A lux is a lumen per m2. So, what is a lumen? Technically, it’s one candela emitted uniformly across a solid angle of 1 steradian. That’s not helping, is it? Examine the figure above. The source emits light (energy) in all directions simultaneously. -
2.1 Definition of the SI
CCPR/16-53 Modifications to the Draft of the ninth SI Brochure dated 16 September 2016 recommended by the CCPR to the CCU via the CCPR president Takashi Usuda, Wednesday 14 December 2016. The text in black is a selection of paragraphs from the brochure with the section title for indication. The sentences to be modified appear in red. 2.1 Definition of the SI Like for any value of a quantity, the value of a fundamental constant can be expressed as the product of a number and a unit as Q = {Q} [Q]. The definitions below specify the exact numerical value of each constant when its value is expressed in the corresponding SI unit. By fixing the exact numerical value the unit becomes defined, since the product of the numerical value {Q} and the unit [Q] has to equal the value Q of the constant, which is postulated to be invariant. The seven constants are chosen in such a way that any unit of the SI can be written either through a defining constant itself or through products or ratios of defining constants. The International System of Units, the SI, is the system of units in which the unperturbed ground state hyperfine splitting frequency of the caesium 133 atom Cs is 9 192 631 770 Hz, the speed of light in vacuum c is 299 792 458 m/s, the Planck constant h is 6.626 070 040 ×1034 J s, the elementary charge e is 1.602 176 620 8 ×1019 C, the Boltzmann constant k is 1.380 648 52 ×1023 J/K, 23 -1 the Avogadro constant NA is 6.022 140 857 ×10 mol , 12 the luminous efficacy of monochromatic radiation of frequency 540 ×10 hertz Kcd is 683 lm/W. -
Guide for the Use of the International System of Units (SI)
Guide for the Use of the International System of Units (SI) m kg s cd SI mol K A NIST Special Publication 811 2008 Edition Ambler Thompson and Barry N. Taylor NIST Special Publication 811 2008 Edition Guide for the Use of the International System of Units (SI) Ambler Thompson Technology Services and Barry N. Taylor Physics Laboratory National Institute of Standards and Technology Gaithersburg, MD 20899 (Supersedes NIST Special Publication 811, 1995 Edition, April 1995) March 2008 U.S. Department of Commerce Carlos M. Gutierrez, Secretary National Institute of Standards and Technology James M. Turner, Acting Director National Institute of Standards and Technology Special Publication 811, 2008 Edition (Supersedes NIST Special Publication 811, April 1995 Edition) Natl. Inst. Stand. Technol. Spec. Publ. 811, 2008 Ed., 85 pages (March 2008; 2nd printing November 2008) CODEN: NSPUE3 Note on 2nd printing: This 2nd printing dated November 2008 of NIST SP811 corrects a number of minor typographical errors present in the 1st printing dated March 2008. Guide for the Use of the International System of Units (SI) Preface The International System of Units, universally abbreviated SI (from the French Le Système International d’Unités), is the modern metric system of measurement. Long the dominant measurement system used in science, the SI is becoming the dominant measurement system used in international commerce. The Omnibus Trade and Competitiveness Act of August 1988 [Public Law (PL) 100-418] changed the name of the National Bureau of Standards (NBS) to the National Institute of Standards and Technology (NIST) and gave to NIST the added task of helping U.S. -
Recommended Light Levels
Recommended Light Levels Recommended Light Levels (Illuminance) for Outdoor and Indoor Venues This is an instructor resource with information to be provided to students as the instructor sees fit. Light Level or Illuminance, is the amount of light measured in a plane surface (or the total luminous flux incident on a surface, per unit area). The work plane is where the most important tasks in the room or space are performed. Measuring Units of Light Level - Illuminance Illuminance is measured in foot candles (ftcd, fc, fcd) or lux (in the metric SI system). A foot candle is actually one lumen of light density per square foot; one lux is one lumen per square meter. • 1 lux = 1 lumen / sq meter = 0.0001 phot = 0.0929 foot candle (ftcd, fcd) • 1 phot = 1 lumen / sq centimeter = 10000 lumens / sq meter = 10000 lux • 1 foot candle (ftcd, fcd) = 1 lumen / sq ft = 10.752 lux Common Light Levels Outdoors from Natural Sources Common light levels outdoor at day and night can be found in the table below: Illumination Condition (ftcd) (lux) Sunlight 10,000 107,527 Full Daylight 1,000 10,752 Overcast Day 100 1,075 Very Dark Day 10 107 Twilight 1 10.8 Deep Twilight .1 1.08 Full Moon .01 .108 Quarter Moon .001 .0108 Starlight .0001 .0011 Overcast Night .00001 .0001 Common Light Levels Outdoors from Manufactured Sources The nomenclature for most of the types of areas listed in the table below can be found in the City of Los Angeles, Department of Public Works, Bureau of Street Lighting’s “DESIGN STANDARDS AND GUIDELINES” at the URL address under References at the end of this document. -
Relationships of the SI Derived Units with Special Names and Symbols and the SI Base Units
Relationships of the SI derived units with special names and symbols and the SI base units Derived units SI BASE UNITS without special SI DERIVED UNITS WITH SPECIAL NAMES AND SYMBOLS names Solid lines indicate multiplication, broken lines indicate division kilogram kg newton (kg·m/s2) pascal (N/m2) gray (J/kg) sievert (J/kg) 3 N Pa Gy Sv MASS m FORCE PRESSURE, ABSORBED DOSE VOLUME STRESS DOSE EQUIVALENT meter m 2 m joule (N·m) watt (J/s) becquerel (1/s) hertz (1/s) LENGTH J W Bq Hz AREA ENERGY, WORK, POWER, ACTIVITY FREQUENCY second QUANTITY OF HEAT HEAT FLOW RATE (OF A RADIONUCLIDE) s m/s TIME VELOCITY katal (mol/s) weber (V·s) henry (Wb/A) tesla (Wb/m2) kat Wb H T 2 mole m/s CATALYTIC MAGNETIC INDUCTANCE MAGNETIC mol ACTIVITY FLUX FLUX DENSITY ACCELERATION AMOUNT OF SUBSTANCE coulomb (A·s) volt (W/A) C V ampere A ELECTRIC POTENTIAL, CHARGE ELECTROMOTIVE ELECTRIC CURRENT FORCE degree (K) farad (C/V) ohm (V/A) siemens (1/W) kelvin Celsius °C F W S K CELSIUS CAPACITANCE RESISTANCE CONDUCTANCE THERMODYNAMIC TEMPERATURE TEMPERATURE t/°C = T /K – 273.15 candela 2 steradian radian cd lux (lm/m ) lumen (cd·sr) 2 2 (m/m = 1) lx lm sr (m /m = 1) rad LUMINOUS INTENSITY ILLUMINANCE LUMINOUS SOLID ANGLE PLANE ANGLE FLUX The diagram above shows graphically how the 22 SI derived units with special names and symbols are related to the seven SI base units. In the first column, the symbols of the SI base units are shown in rectangles, with the name of the unit shown toward the upper left of the rectangle and the name of the associated base quantity shown in italic type below the rectangle. -
International System of Units (SI)
International System of Units (SI) National Institute of Standards and Technology (www.nist.gov) Multiplication Prefix Symbol factor 1018 exa E 1015 peta P 1012 tera T 109 giga G 106 mega M 103 kilo k 102 * hecto h 101 * deka da 10-1 * deci d 10-2 * centi c 10-3 milli m 10-6 micro µ 10-9 nano n 10-12 pico p 10-15 femto f 10-18 atto a * Prefixes of 100, 10, 0.1, and 0.01 are not formal SI units From: Downs, R.J. 1988. HortScience 23:881-812. International System of Units (SI) Seven basic SI units Physical quantity Unit Symbol Length meter m Mass kilogram kg Time second s Electrical current ampere A Thermodynamic temperature kelvin K Amount of substance mole mol Luminous intensity candela cd Supplementary SI units Physical quantity Unit Symbol Plane angle radian rad Solid angle steradian sr From: Downs, R.J. 1988. HortScience 23:881-812. International System of Units (SI) Derived SI units with special names Physical quantity Unit Symbol Derivation Absorbed dose gray Gy J kg-1 Capacitance farad F A s V-1 Conductance siemens S A V-1 Disintegration rate becquerel Bq l s-1 Electrical charge coulomb C A s Electrical potential volt V W A-1 Energy joule J N m Force newton N kg m s-2 Illumination lux lx lm m-2 Inductance henry H V s A-1 Luminous flux lumen lm cd sr Magnetic flux weber Wb V s Magnetic flux density tesla T Wb m-2 Pressure pascal Pa N m-2 Power watt W J s-1 Resistance ohm Ω V A-1 Volume liter L dm3 From: Downs, R.J. -
Cosmology Meets Condensed Matter
Cosmology Meets Condensed Matter Mark N. Brook Thesis submitted to the University of Nottingham for the degree of Doctor of Philosophy. July 2010 The Feynman Problem-Solving Algorithm: 1. Write down the problem 2. Think very hard 3. Write down the answer – R. P. Feynman att. to M. Gell-Mann Supervisor: Prof. Peter Coles Examiners: Prof. Ed Copeland Prof. Ray Rivers Abstract This thesis is concerned with the interface of cosmology and condensed matter. Although at either end of the scale spectrum, the two disciplines have more in common than one might think. Condensed matter theorists and high-energy field theorists study, usually independently, phenomena embedded in the structure of a quantum field theory. It would appear at first glance that these phenomena are disjoint, and this has often led to the two fields developing their own procedures and strategies, and adopting their own nomenclature. We will look at some concepts that have helped bridge the gap between the two sub- jects, enabling progress in both, before incorporating condensed matter techniques to our own cosmological model. By considering ideas from cosmological high-energy field theory, we then critically examine other models of astrophysical condensed mat- ter phenomena. In Chapter 1, we introduce the current cosmological paradigm, and present a somewhat historical overview of the interplay between cosmology and condensed matter. Many concepts are introduced here that later chapters will follow up on, and we give some examples in which condensed matter physics has had a very real effect on informing cosmology. We also reflect on the most recent incarnations of the condensed matter / cosmology interplay, and the future of these developments. -
1 “A Big History of the Universe for Secondary Education” PI
“A Big History of the Universe for Secondary Education” PI: Tara Firenzi Co-Is: Joel Primack, Ph.D, Nancy Abrams, Darrell Steely, Joel Tarbox Collaborator: Doris B. Ash, Ph.D GSR: Zoe Buck Consultant: Solana Pyne Summary Overview Over the last decade, world history and astrophysics have become more and more similar in the way they examine the origins of the universe. Principally, world historians and social science educators have come to realize that the origin of our universe is the beginning of our human story. Though the incorporation of these ideas into secondary curricula is not yet widespread, well respected efforts such as “World History for Us All,” a project of the National Center for History in Schools at UCLA, have strongly advocated for the incorporation of the history of the universe in world history curricula. As put forth by books like David Christian’s Maps of Time: An Introduction to Big History (2005), these ideas will no doubt become a more significant part of both history and science instruction in secondary schools in the near future, and make instruction in both areas more interdisciplinary. In scientific fields, of course, the importance of the origins of the universe has long been understood. Bringing us to a new level of understanding on the subject of these origins, UCSC Professor Joel Primack and Nancy Abrams have recently introduced a number of new ideas about the connections between advanced scientific theories and the historical importance of the origins of the universe as discussed in their book, The View From the Center of the Universe: Discovering Our Extraordinary Place in the Cosmos (2006).