DOCSLIB.ORG

Dark Matter and Dark Energy

Total Page：16

File Type：pdf, Size：1020Kb

Download full-text PDF Read full-text
Dark Matter and Dark Energy HTS Teologiese Studies/Theological Studies ISSN: (Online) 2072-8050, (Print) 0259-9422 Page 1 of 8 Original Research The building blocks of the universe Author: I review the state of knowledge of the composition of the universe for a non-specialist audience. 1,2 Anslyn J. John The universe is built up of four components. These are radiation, baryonic (ordinary) matter, Affiliation: dark matter and dark energy. In this article, a quick outline of the theory of Big Bang 1Department of Physics, nucleosynthesis is presented, and the origin of the elements is explained. Cosmology requires Faculty of Science, the presence of dark matter, which forms most of the mass of the universe, and dark energy, Stellenbosch University, which drives the acceleration of the expansion. The dark sector is motivated, and possible Stellenbosch, South Africa explanations are stated. 2National Institute for Contribution: As part of this special collection on building blocks, the building blocks of the Theoretical and Computational Sciences universe are discussed and unsolved problems and proposed solutions are highlighted. (NITheCS), South Africa Keywords: cosmology; nucleosynthesis; dark matter; dark energy; cosmological constant; Corresponding author: general relativity; galaxies; particle physics. Anslyn John, [email protected] Dates: Introduction Received: 10 May 2021 Cosmology is the scientific study of the origin and development of the universe on the largest Accepted: 12 July 2021 Published: 25 Aug. 2021 scales. Today, the standard model of cosmology is a cornerstone of physics and astronomy. This is attested to by the award of four Nobel Prizes for research in cosmology. These awards, in How to cite this article: chronological order, are: John, A.J., 2021, ‘The building blocks of the universe’, 1. Arno A. Penzias and Robert W. Wilson, 1978 – ‘for their discovery of cosmic microwave HTS Teologiese Studies/ background radiation’. Theological Studies 77(3), 2. John C. Mather and George F. Smoot, 2006 – ‘for their discovery of the blackbody form and a6831. https://doi. org/10.4102/hts.v77i3.6831 anisotropy of the cosmic microwave background radiation’. 3. Saul Perlmutter, Brian P. Schmidt and Adam G. Riess, 2011 – ‘for the discovery of the Copyright: accelerating expansion of the Universe through observations of distant supernovae’. © 2021. The Authors. 4. James Peebles, 2019 – ‘for theoretical discoveries in physical cosmology’. Licensee: AOSIS. This work is licensed under the Creative Commons Sophisticated models of the universe, making quantitative predictions, were developed soon after Attribution License. the advent of Einstein’s theory of general relativity in 1915 (Weinberg 1972). Astronomers had uncovered a universe lacking preferred positions or directions in space. This was in accord with the Copernican principle, which states that we do not occupy a special place in the universe. Relativists naturally incorporated spatial homogeneity and isotropy into their models, but surprisingly discovered that the theory predicted that the universe should be expanding. An expanding universe was at odds with contemporary observational evidence, and theorists like Einstein attempted to salvage their cosmological models by forcing them to be static. This was abandoned after 1929 when observations of distant galaxies revealed that they were moving away from the Milky Way at speeds proportional to their distances (Kirshner 2004). This empirical formula is now known as the Hubble–Lemaître law (Livio 2011) and follows very naturally from the dynamic cosmological models in general relativity. A picture of a universe that began to expand at some finite time in its past began to emerge. This was later termed the Big Bang model. The next major development in the history of cosmology was the theory of Big Bang nucleosynthesis (BBN). All of the chemical elements were hypothesised to have been formed by nuclear reactions in the hot, dense infancy of the universe. This was described in the tremendously successful Hot Big Bang model (Gamow 1948). It explained the abundances of many of the chemical elements Read online: seen today. It also predicted the existence of relic radiation from the time that the universe became Scan this QR transparent to light. This radiation persisted and was famously observed in the microwave part code with your smart phone or of the electromagnetic spectrum (Penzias & Wilson 1965). mobile device to read online. Note: Special Collection: Challenging Building Blocks, sub-edited by Chris Jones (Stellenbosch University) and Juri van den Heever (Stellenbosch University). http://www.hts.org.za Open Access Page 2 of 8 Original Research Today the standard model of cosmology is known as the so-called radiation era. As the universe expands the energy ΛCDM or concordance model (Dodelson 2003). It is an density of its constituents decreases because the same extension of the hot Big Bang model, which describes a particles occupy an increasingly larger volume. The radiation universe that began to expand 13.8 billion years ago. The energy density declines at a faster rate than the matter energy early universe was smooth, hot and dense. As it expanded it density. After a period termed matter–radiation equality, the became cooler and more diffuse and structures such as stars dominant contribution to the energy density of the universe and galaxies started to form. The standard model now comes from the matter sector. The matter sector comprises includes two extra ingredients viz. dark matter and dark dark matter and baryonic matter. This is the start of the energy. The CDM part represents cold dark matter – a matter era. Although the energy density of the matter mysterious substance comprising most of the matter of the particles continues to drop as the universe expands, it universe. The Λ refers to dark energy, which accounts for continues to dominate the energy density of the radiation most of the universe’s energy and is responsible for the sector, which drops at an even faster rate. Eventually the acceleration of the universe’s expansion at late times. The energy density of the matter particles drops below the energy leading candidate for dark energy is the cosmological density of the dark energy component. After this time, the constant, which is historically denoted by the Greek letter Λ. universe is dominated by dark energy and starts to expand exponentially. This is in contrast to the earlier radiation and There are many excellent popular accounts of cosmology, matter eras where the universe experienced power law several of which were written by some of the field’s leading expansion. practitioners (Chown 2010; Hawking 2009; Weinberg 1977). The reader is encouraged to refer to these books for more In the next section I will describe how the ordinary matter complete accounts. I will not attempt an exhaustive review of was formed and how radiation from this process persisted. I the subject. will then describe dark matter and dark energy before concluding. Instead, I will focus on addressing the following question in a manner that may be accessible to the enthusiastic layperson: Big Bang nucleosynthesis what is the universe made of? The short answer is that the The ordinary matter we are familiar with is composed of universe is built of four substances: radiation, baryonic chemical elements. These range in mass from the lightest matter, dark matter and dark energy. elements, hydrogen and helium, to the heaviest naturally occurring elements like uranium. The basic properties of What are these substances? these elements are described by the periodic table, ascribed 1. Radiation: This consists of photons and neutrinos and to Mendeleev. For more details about the building blocks of makes up 10-3% of the total energy. matter, the reader is referred to the relevant article (Haynes & 2. Baryonic matter: This is the ordinary, familiar material Blackie 2021) in this edition of the journal. including all of the chemical elements and compounds that we find in planets, stars, gas clouds and plasmas. The science of how the atoms of these elements combine to Baryonic matter only comprises about 4% of the universe’s form molecules and compounds in nature and the laboratory energy budget. is the purview of chemistry. Explaining the origin of these 3. Dark matter: This is an exotic substance that does not elements is the task of physics. Although individual atoms emit or absorb light. It is not made up of any of the known may gain or lose electrons, the fundamental characteristics of elementary particles. Dark matter appears to require new an element are determined by the number of protons in their physics. It makes up 23% of the total energy of the nuclei. universe and comprises most of its mass. 4. Dark energy: This is the name given to the phenomenon Nuclei are composed of positively charged protons and responsible for the late time acceleration of the universe’s electrically neutral neutrons. A neutron is slightly heavier expansion. Like dark matter, this cannot be explained by than a proton, and both of these particles are about 2000 existing physics and requires extensions to our theories of times heavier than an electron. An electron has a negative fundamental particles. Einstein’s cosmological constant charge, which perfectly balances the positive charge of a (Λ) is the leading candidate for dark energy, which makes proton. As a neutral atom has the same number of electrons up 73% of today’s energy budget. and protons, the nucleus essentially contains all of the mass of an atom. Dividing the building blocks of the universe into these four substances is convenient as each of these substances In nuclear and particle physics the equivalence of mass and contributes to the total energy of the universe. Moreover, energy is a vital concept. This is a consequence of Einstein’s each of these substances affects the overall dynamics of the famous formula, E = mc2, where c = 3×108 m/s is the speed of universe in different ways at particular times.
Load more

Recommended publications
  • Asia Pacific Physics Newsletter
    Asia Pacific Physics Newsletter March 2016 Volume 5 • Number 1 worldscinet.com/appn Takaaki Kajita 2015 Physics Nobel Laureate published by Institute of Advanced Studies, Nanyang Technological University (IAS@NTU) and South East Asia Theoretical Physics Association (SEATPA) South East Asia Theoretical Physics Association Asia Pacific Physics Newsletter March 2016 • Volume 5 • Number 1 A publication of the IAS@NTU Singapore and SEATPA Asia Pacific Physics Newsletter publishes articles reporting frontier discoveries in EDITORIAL physics, research highlights, and news to facilitate interaction, collaboration and 3 cooperation among physicists in Asia Pacific physics community. PEOPLE Editor-in-Chief 4 “Observing the Distant Supernova” — Interview with Kok Khoo Phua Nobel Laureate Prof Brian Schmidt Associate Editor-in-Chief “Discovering the W and Z Bosons” — Interview with Swee Cheng Lim Nobel Laureate Prof Carlo Rubbia SEATPA Committee Christopher C Bernido Phil Chan Leong Chuan Kwek Choy Heng Lai Swee Cheng Lim Ren Bao Liu Hwee Boon Low Anh Ký Nguyên Choo Hiap Oh OPINION AND COMMENTARY Kok Khoo Phua 10 China’s Great Scientific Leap Forward: Completion of a Roh Suan Tung Preecha Yupapin planned ‘Great Collider’ would transform particle physics Hishamuddin Zainuddin Freddy Zen Editorial Team NEWS Sen Mu 12 CityU’s Institute for Advanced Study will Champion Bold New Han Sun Chi Xiong Research Initiatives Case made for 'Ninth Planet' Graphic Designers Chuan Ming Loo Erin Ong Cover Photo: "Takaaki Kajita 5171- 2015" by Bengt Nyman - Own work.
    [Show full text]
  • Is the Universe Ringing Like a Crystal Glass? by Tara Burcham, University of Southern Mississippi
    Home / Astronomy & Space / Astronomy JUNE 26, 2015 Is the universe ringing like a crystal glass? by Tara Burcham, University of Southern Mississippi The standard view of the expanding universe. Many know the phrase "the big bang theory." There's even a top television comedy series with that as its title. According to scientists, the universe began with the "big bang" and expanded to the size it is today. Yet, the gravity of all of this matter, stars, gas, galaxies, and mysterious dark matter, tries to pull the universe back together, slowing down the expansion. Now, two physicists at The University of Southern Mississippi, Lawrence Mead and Harry Ringermacher, have discovered that the universe might not only be expanding, but also oscillating or "ringing" at the same time. Their paper on the topic has been published in the April 2015 issue of the Astronomical Journal. In 1978 Arno Allan Penzias and Robert Woodrow Wilson received the Nobel prize for their 1964 discovery of the key signature of this theory, the primal radiation from the early universe known as the "cosmic microwave background" (CMB). "Then in 1998 the finding that the universe was not only expanding, but was speeding up, or accelerating in its expansion was a shock when it was discovered simultaneously by east coast and west coast teams of astronomers and physicists," said Mead. "A new form of matter, dark energy, repulsive in nature, was responsible for the speed-up. The teams led by Saul Perlmutter, Adam Riess, and Brian Schmidt won the 2011 Nobel Prize in Physics for that discovery." According to Mead and Ringermacher, this change from slowing down to speeding up (the transition time) took place approximately 6 to 7 billion years ago.
    [Show full text]
  • The Nobel Prize in Physics 2011
    PRESSMEDDELANDE Press release 4 October 2011 The Nobel Prize in Physics 2011 The Royal Swedish Academy of Sciences has decided to award the Nobel Prize in Physics for 2011 with one half to Saul Perlmutter The Supernova Cosmology Project Lawrence Berkeley National Laboratory and University of California, Berkeley, CA, USA and the other half to Brian P. Schmidt and Adam G. Riess The High-z Supernova Search Team The High-z Supernova Search Team Australian National University, Johns Hopkins University and Space Telescope Science Institute, Weston Creek, Australia Baltimore, MD, USA “for the discovery of the accelerating expansion of the Universe through observations of distant supernovae”. Written in the stars “Some say the world will end in fre, some say in ice…” * For almost a century, the Universe has been known to be , 1920 What will be the fnal destiny of the Universe? Probably expanding as a consequence of the Big Bang about 14 billion it will end in ice, if we are to believe this year’s Nobel years ago. However, the discovery that this expansion is accele- rating is astounding. If the expansion will continue to speed up Fire and Ice Fire Laureates in Physics. They have studied several dozen the Universe will end in ice. exploding stars, called supernovae, and discovered that the Universe is expanding at an ever-accelerating rate. The acceleration is thought to be driven by dark energy, The discovery came as a complete surprise even to the but what that dark energy is remains an enigma – perhaps * Robert Frost, * Robert Frost, Laureates themselves.
    [Show full text]
  • Timeline Cosmology
    Timeline Cosmology • 2nd Millennium BCEBC Mesopotamian cosmology has a flat,circular Earth enclosed in a cosmic Ocean • 12th century BCEC Rigveda has some cosmological hymns, most notably the Nasadiya Sukta • 6th century BCE Anaximander, the first (true) cosmologist ‐ pre‐Socratic philosopher from Miletus, Ionia ‐ Nature ruled by natural laws ‐ Apeiron (boundless, infinite, indefinite), that out of which the universe originates • 5th century BCE Plato ‐ Timaeus ‐ dialogue describing the creation of the Universe, ‐ demiurg created the world on the basis of geometric forms (Platonic solids) • 4th century BCE Aristotle ‐ proposes an Earth‐centered universe in which the Earth is stationary and the cosmos, is finite in extent but infinite in time • 3rd century BCE Aristarchus of Samos ‐ proposes a heliocentric (sun‐centered) Universe, based on his conclusion/determination that the Sun is much larger than Earth ‐ further support in 2nd century BCE by Seleucus of Seleucia • 3rd century BCE Archimedes ‐ book The Sand Reckoner: diameter of cosmos ~ 2 lightyears ‐ heliocentric Universe not possible • 3rd century BCE Apollonius of Perga ‐ epicycle theory for lunar and planetary motions • 2nd century CE Ptolemaeus ‐ Almagest/Syntaxis: culmination of ancient Graeco‐Roman astronomy ‐ Earth‐centered Universe, with Sun, Moon and planets revolving on epicyclic orbits around Earth • 5th‐13th century CE Aryabhata (India) and Al‐Sijzi (Iran) propose that the Earth rotates around its axis. First empirical evidence for Earth’s rotation by Nasir al‐Din al‐Tusi. • 8th century CE Puranic Hindu cosmology, in which the Universe goes through repeated cycles of creation, destruction and rebirth, with each cycle lasting 4.32 billion years. • • 1543 Nicolaus Copernicus ‐ publishes heliocentric universe in De Revolutionibus Orbium Coelestium ‐ implicit introduction Copernican principle: Earth/Sun is not special • 1609‐1632 Galileo Galilei ‐ by means of (telescopic) observations, proves the validity of the heliocentric Universe.
    [Show full text]
  • The Shaw Prize 2006 Award Presentation Ceremony the Shaw Prize
    The Shaw Prize 2006 Award Presentation Ceremony The Shaw Prize The Shaw Prize is an international award which honours individuals for achieving distinguished breakthroughs in academic and scientific research or applications, who have made outstanding contributions in culture and the arts, or who in other domains have achieved excellence. The award is dedicated to furthering societal progress, enhancing quality of life, and enriching humanity's spiritual civilization. Preference will be given to individuals whose significant work was recently achieved, or whose works' profound impact becomes increasingly apparent. Founder's Biographical Note The Shaw Prize was established under the auspices of Mr. Run Run Shaw. Mr. Shaw, born in China in 1907, is a native of Ningbo County, Zhejiang Province. He joined his brother's film company in China in the 1920s. In the 1950s he founded the film company Shaw Brothers (Hong Kong) Limited in Hong Kong. He has been Executive Chairman of Television Broadcasts Limited in Hong Kong since the 1970s. Mr. Shaw has also founded two charities, The Sir Run Run Shaw Charitable Trust and The Shaw Foundation Hong Kong, both dedicated to the promotion of education, scientific and technological research, medical and welfare services, and culture and the arts. ~ 1 ~ Message from the Chief Executive Message from the Founder Knowledge transcends national and Yesterday's discoveries, in the geographical boundaries. Scholars and scientists are the vanguard who competent hands of today's advances the frontier of knowledge, gifted innovators, empower and enhances our quality of life and enriches the civilization of inspire human society to strive mankind.
    [Show full text]
  • The Messenger
    ESO 50th anniversary celebrations The Messenger Allocation of observing programmes La Silla–QUEST Survey b Pictoris and RS Puppis No. 150 – December 2012 – 150 No. ESO 50th Anniversary A Milestone for The Messenger in ESO’s 50th Anniversary Year Tim de Zeeuw1 nent launch of the construction of the trated book by Govert Schilling and Lars 39.3-metre diameter European Extremely Christensen (Europe to the Stars), many Large Telescope on Cerro Armazones additional images on the ESO website, 1 ESO with a projected start of operations in exhibitions and competitions, one of the about ten years’ time. Meanwhile, the latter with, as a prize, the opportunity number of Member States has increased to observe at Paranal, and a gala event In May 1974, Adriaan Blaauw launched to 14, with Brazil poised to join as the for representatives of the Member States The Messenger. He stated the goal first from outside Europe as soon as the and key contributors to ESO’s develop- explicitly: “To promote the participation Accession Agreement is ratified. ment, past and present (see the report of ESO staff in what goes on in the on p. 7, with copies of the speeches). In Organisation, especially at places of duty ESO’s mission is to design, construct and this special issue, four former Directors other than our own. Moreover, The operate powerful ground-based observ- General also contribute their reflections Messenger may serve to give the world ing facilities which enable astronomers on the significance of the 50th anniver- outside some impression of what hap­ to make important scientific discoveries sary: Lodewijk Woltjer (1975–1987), pens inside ESO.” Today The Messenger and to play a leading role in promoting Harry van der Laan (1988–1992), Riccardo is known the world over, and has reached and organising cooperation in astronomi- Giacconi (1993–1999) and Catherine a major milestone with the publication cal research.
    [Show full text]
  • The Chalonge
    Ecole Internationale Daniel Chalonge-Héctor deVega Science with great intellectual endeavor and a human face La Science qui donne envie Une grande aventure scientifique et humaine 30 Years of Activity. Calling for Understanding Open and Free Science - Open and Free Access Welcome to the Chalonge – de Vega School: A Laboratory of Ideas, Research, Training and Scientific Culture _________________________________________________________________________ A beacon at the forefront of physical cosmology and astrofundamental physics with novel scientific research, projects and ideas, international collaboration and careful interdisciplinarity, with both Theory and Observations Open to researchers, post-docs, advanced students of different disciplines in the field, both theorists, experimentalists, observers. Open to specialists and non-specialists in the field, as well as to teachers, communicators, journalists. https://chalonge-devega.fr/ PROGRAMME 2021 OPEN SCIENCE AND IN FREE ACCESS SCIENCE OUVERTE ET EN LIBRE ACCES In remote 16h00 PARIS TIME THURSDAY 21 JANUARY 2021 Prof. Dr Carlos O. LOUSTO’ (Professor at RIT - Rochester Institute of Technology- School of Mathematical Sciences, Co-Director of the Center for Computational Relativity and Gravitation, Rochester NY): From simulations of binary black holes to insights into astrophysics and gravitational waves THURSDAY 28 JANUARY 2021 Prof. Dr Gérard ‘T HOOFT, Nobel Prize in Physics, Professor at the Institute for Theoretical Physics, Utrecht University and Spinoza Institute: Quantum Black Holes WEDNESDAY 3 FEBRUARY 2021 Prof. Dr Reinhard GENZEL, Nobel Prize in Physics, Director at the Max-Planck-Institut für Extraterrestrische Physik, Garching: A Forty-Year Journey WEDNESDAY 10 FEBRUARY 2021 Prof. Dr Barry C. BARISH, Nobel Prize in Physics, LIGO Caltech Laboratory, LSCEC, California Institute of Technology, Pasadena: Gravitational-Wave Detections THURSDAY 4 MARCH 2021 Prof.
    [Show full text]
  • Iau Executive Committee
    IAU EXECUTIVE COMMITTEE PRESIDENT VICE-PRESIDENTS Catherine J. Cesarsky Beatriz Barbuy Giancarlo Setti ESO Dpto Astronomia Dipto di Astronomia Karl-Schwarzschild-Str 2 IAG Univ di Bologna DE - 85748 Garching Univ de São Paulo Via Ranzani 1 Germany Rua do Matão 1226 IT - 40127 Bologna Tel +49 89 3200 6488 Cidade Universitária Italy Fax +49 89 3202 362 BR - São Paulo, SP 05508- Tel +39 051 6399 365 [email protected] 900 Fax +39 051 2095 700 Brazil [email protected] PRESIDENT-ELECT Tel +55 11 3091 2810 Fax +55 11 3091 2860 Robert Williams Brian Warner [email protected] Astronomy Dept STScI 3700 San Martin Dr Univ Cape Town US - Baltimore MD 21218- Cheng Fang Private Bag 2410 Dept Astronomy ZA - 7700 Rondebosch USA Nanjing University South Africa Tel +1 410 338 4963 22 Hankou Rd Tel +27 21 650 2391 Fax +1 410 338 2617 CN - Nanjing 210093 Fax +27 21 650 3342 [email protected] China PR [email protected] Tel +86 258 359 6817 GENERAL SECRETARY Fax +86 258 359 6817 ADVISERS [email protected] Ronald D. Ekers Karel A. van der Hucht SRON Netherlands IAU Past President Institute for Space Martha P. Haynes CSIRO / ATNF Research Astronomy Dept PO Box 76 Sorbonnelaan 2 Cornell University AU - Epping NSW 1710 NL - 3584 CA Utrecht 530 Space Sciences Bldg Australia the Netherlands US - Ithaca NY 14853-6801 Tel +61 2 9372 4600 Tel +31 30 2535 729/5600 USA Fax +61 2 9372 4450 Fax +31 30 2540 860 Tel +1 607 255 0610 [email protected] [email protected] Fax +1 607 255 8803 [email protected] Oddbjørn Engvold ASSISTANT GENERAL Past General Secretary SECRETARY George K.
    [Show full text]
  • Science Librarians Analysis of the 2011 Nobel Prize in Physics: the Work of Saul Perlmutter, Brian P
    This article was downloaded by: [Fondren Library, Rice University ], [Debra Kolah] On: 19 March 2012, At: 08:04 Publisher: Routledge Informa Ltd Registered in England and Wales Registered Number: 1072954 Registered office: Mortimer House, 37-41 Mortimer Street, London W1T 3JH, UK Science & Technology Libraries Publication details, including instructions for authors and subscription information: http://www.tandfonline.com/loi/wstl20 Science Librarians Analysis of the 2011 Nobel Prize in Physics: The Work of Saul Perlmutter, Brian P. Schmidt, and Adam G. Riess Debra Kolah a & Michael T. Fosmire b a Fondren Library, Rice University, Houston, Texas b Purdue University Libraries, West Lafayette, Indiana Available online: 12 Mar 2012 To cite this article: Debra Kolah & Michael T. Fosmire (2012): Science Librarians Analysis of the 2011 Nobel Prize in Physics: The Work of Saul Perlmutter, Brian P. Schmidt, and Adam G. Riess, Science & Technology Libraries, 31:1, 12-31 To link to this article: http://dx.doi.org/10.1080/0194262X.2012.648112 PLEASE SCROLL DOWN FOR ARTICLE Full terms and conditions of use: http://www.tandfonline.com/page/terms-and-conditions This article may be used for research, teaching, and private study purposes. Any substantial or systematic reproduction, redistribution, reselling, loan, sub-licensing, systematic supply, or distribution in any form to anyone is expressly forbidden. The publisher does not give any warranty express or implied or make any representation that the contents will be complete or accurate or up to date. The accuracy of any instructions, formulae, and drug doses should be independently verified with primary sources. The publisher shall not be liable for any loss, actions, claims, proceedings, demand, or costs or damages whatsoever or howsoever caused arising directly or indirectly in connection with or arising out of the use of this material.
    [Show full text]
  • Lindau Nobel Laureate Meetings South African Alumni Narratives © Academy of Science of South Africa August 2020
    Lindau Nobel Laureate Meetings South African Alumni Narratives © Academy of Science of South Africa August 2020 ISBN 978-1-928496-28-1 Cite: Academy of Science of South Africa (ASSAf), (2020). DOI http://dx.doi.org/10.17159/assaf.2019/0063 Published by: Academy of Science of South Africa (ASSAf) PO Box 72135, Lynnwood Ridge, Pretoria, South Africa, 0040 Tel: +27 12 349 6600 • Fax: +27 86 576 9520 E-mail: [email protected] Reproduction is permitted, provided the source and publisher are appropriately acknowledged. The Academy of Science of South Africa (ASSAf) was inaugurated in May 1996. It was formed in response to the need for an Academy of Science consonant with the dawn of democracy in South Africa: activist in its mission of using science and scholarship for the benefit of society, with a mandate encompassing all scholarly disciplines that use an open-minded and evidence-based approach to build knowledge. ASSAf thus adopted in its name the term ‘science’ in the singular as reflecting a common way of enquiring rather than an aggregation of different disciplines. Its Members are elected on the basis of a combination of two principal criteria, academic excellence and significant contributions to society. The Parliament of South Africa passed the Academy of Science of South Africa Act (No 67 of 2001), which came into force on 15 May 2002. This made ASSAf the only academy of science in South Africa officially recognised by government and representing the country in the international community of science academies and elsewhere. Views expressed are those of the individuals and not necessarily those of the Academy nor a consensus view of the Academy based on an in-depth evidence-based study.
    [Show full text]
  • Download Nocturna Program
    A DARK SKY PARTY AT SPRING BAY MILL saturday 14 august 3PM Doors Open 3:45PM Welcome to Country 4PM Professor Brian Schmidt 5PM Countdown to Sundown Performance 5:26PM Sunset 6PM Dark Sky Tasmania Talks 6:30PM Astrophotography Workshop (ticketed) 7PM Theresa Sainty 7:20PM Dr Lila Landowski 8:45PM Chasing Auroras talk with Cam Blake and Luke O'Brien Live Music from 5PM Snacks and Bars from 3PM Meals from 5PM Merriment til late Image by Cam Blake Professor Brian Schmidt - 4pm, Tin Shed Ke ynote address Professor Brian Schmidt AC FRS FAA is an astronomer, Nobel laureate, and the Vice-Chancellor and President of the Australian National University. One of Australia's most eminent scientists, Professor Schmidt shared the 2011 Nobel Prize in Physics for observations of distant supernovae (exploding stars), leding to the discovery of the accelerating expansion of the universe. In addition to his work on supernovae, Professor Schmidt also chases after Gamma Ray Bursts, and led the team that built SkyMapper, a state-of-the-art, wide-field survey telescope that aims to create the first comprehensive digital survey of the entire southern sky. Gabriella Allegretto - 6pm, Tin Shed Access to dark skies and light pollution as emerging environmental justice issues Light pollution is becoming a major topic of research and addressing light pollution is an emerging priority for policy and practice. Yet light pollution issues are intertwined with another important concept — dark skies. Addressing light pollution, at least in part, aims to restore access to dark skies for humans and non-humans alike.
    [Show full text]
  • Annual Report 2020 Online Science Days 28 June – 1 July 2020 Annual Report 2020 Online Science Days 28 June – 1 July 2020 Contents Online Science Days 2020
    Annual Report 2020 Online Science Days 28 June – 1 July 2020 Annual Report 2020 Online Science Days 28 June – 1 July 2020 Contents Online Science Days 2020 Against the Odds: Science Brought Us Closer Together 4 Being a Scientist in Challenging Times Sustainable Chemistry Outreach Projects and Mission Education Resume and Outlook by Council and Foundation International Scientific Collaboration 14 Innovation by Evolution 46 Lindau Alumni Network 83 Opening 8 Programme and Impressions From Lindau Harbour The Lindau Guidelines 2020 16 Batteries and the Transition Towards Renewable Energy 47 Online Science@School 86 A Good Time to Give Progress a New Dynamic 10 Women in Science 20 Green Chemistry – Green Fuels 48 Lindau Mediatheque 87 Greeting From Federal Minister for Education and Research Anja Karliczek Starting Careers 22 Beyond (Everyday) Science Educational Outreach 88 Greetings From Bavaria and Baden-Württemberg 11 The Centenarian 24 The Revolutionary Reform of the Metric System 52 Lindau Science Trail and Nobel Laureate Pier 90 The Federal States Welcome Participants of the Online Science Days SARS-CoV-2: A Universal Paradigm Shift My Brain and Me 53 Lindau Matinee 91 Programme Structure 12 Corona – The Role of Science in Times of Crisis 28 The Impact of COVID-19 on Children 54 Communications 94 Overview With all Sessions Immunity 30 A Time of Lethal Ambiguities 55 Video Productions 95 Academic Partners 68 Online Expo and Application Process Inequalities and COVID-19 31 Lindau Alumni, Young Scientists, Young Economists Lindau Blog 96
    [Show full text]