APS News July 2019, Vol. 28, No.7
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Simulating Physics with Computers
International Journal of Theoretical Physics, VoL 21, Nos. 6/7, 1982 Simulating Physics with Computers Richard P. Feynman Department of Physics, California Institute of Technology, Pasadena, California 91107 Received May 7, 1981 1. INTRODUCTION On the program it says this is a keynote speech--and I don't know what a keynote speech is. I do not intend in any way to suggest what should be in this meeting as a keynote of the subjects or anything like that. I have my own things to say and to talk about and there's no implication that anybody needs to talk about the same thing or anything like it. So what I want to talk about is what Mike Dertouzos suggested that nobody would talk about. I want to talk about the problem of simulating physics with computers and I mean that in a specific way which I am going to explain. The reason for doing this is something that I learned about from Ed Fredkin, and my entire interest in the subject has been inspired by him. It has to do with learning something about the possibilities of computers, and also something about possibilities in physics. If we suppose that we know all the physical laws perfectly, of course we don't have to pay any attention to computers. It's interesting anyway to entertain oneself with the idea that we've got something to learn about physical laws; and if I take a relaxed view here (after all I'm here and not at home) I'll admit that we don't understand everything. -
Astro2020 Science White Paper Unlocking the Secrets of Late-Stage Stellar Evolution and Mass Loss Through Radio Wavelength Imaging
Astro2020 Science White Paper Unlocking the Secrets of Late-Stage Stellar Evolution and Mass Loss through Radio Wavelength Imaging Thematic Areas: Planetary Systems Star and Planet Formation Formation and Evolution of Compact Objects Cosmology and Fundamental Physics 7 Stars and Stellar Evolution Resolved Stellar Populations and their Environments Galaxy Evolution Multi-Messenger Astronomy and Astrophysics Principal Author: Name: Lynn D. Matthews Institution: Massachusetts Institute of Technology Haystack Observatory Email: [email protected] Co-authors: Mark J Claussen (National Radio Astronomy Observatory) Graham M. Harper (University of Colorado - Boulder) Karl M. Menten (Max Planck Institut fur¨ Radioastronomie) Stephen Ridgway (National Optical Astronomy Observatory) Executive Summary: During the late phases of evolution, low-to-intermediate mass stars like our Sun undergo periods of extensive mass loss, returning up to 80% of their initial mass to the interstellar medium. This mass loss profoundly affects the stellar evolutionary history, and the resulting circumstellar ejecta are a primary source of dust and heavy element enrichment in the Galaxy. However, many details concerning the physics of late-stage stellar mass loss remain poorly understood, including the wind launching mechanism(s), the mass loss geometry and timescales, and the mass loss histories of stars of various initial masses. These uncertainties have implications not only for stellar astrophysics, but for fields ranging from star formation to extragalactic astronomy and cosmology. Observations at centimeter, millimeter, and submillimeter wavelengths that resolve the radio surfaces and extended atmospheres of evolved arXiv:1903.05592v1 [astro-ph.SR] 13 Mar 2019 stars in space, time, and frequency are poised to provide groundbreaking new insights into these questions in the coming decade. -
Cometary Panspermia a Radical Theory of Life’S Cosmic Origin and Evolution …And Over 450 Articles, ~ 60 in Nature
35 books: Cosmic origins of life 1976-2020 Physical Sciences︱ Chandra Wickramasinghe Cometary panspermia A radical theory of life’s cosmic origin and evolution …And over 450 articles, ~ 60 in Nature he combined efforts of generations supporting panspermia continues to Prof Wickramasinghe argues that the seeds of all life (bacteria and viruses) Panspermia has been around may have arrived on Earth from space, and may indeed still be raining down some 100 years since the term of experts in multiple fields, accumulate (Wickramasinghe et al., 2018, to affect life on Earth today, a concept known as cometary panspermia. ‘primordial soup’, referring to Tincluding evolutionary biology, 2019; Steele et al., 2018). the primitive ocean of organic paleontology and geology, have painted material not-yet-assembled a fairly good, if far-from-complete, picture COMETARY PANSPERMIA – cultural conceptions of life dating back galactic wanderers are normal features have argued that these could not into living organisms, was first of how the first life on Earth progressed A SOLUTION? to the ideas of Aristotle, and that this of the cosmos. Comets are known to have been lofted from the Earth to a coined. The question of how from simple organisms to what we can The word ‘panspermia’ comes from the may be the source of some of the have significant water content as well height of 400km by any known process. life’s molecular building blocks see today. However, there is a crucial ancient Greek roots ‘sperma’ meaning more hostile resistance the idea of as organics, and their cores, kept warm Bacteria have also been found high in spontaneously assembled gap in mainstream understanding - seed, and ‘pan’, meaning all. -
Evolutionary Processes Transpiring in the Stages of Lithopanspermia Ian Von Hegner
Evolutionary processes transpiring in the stages of lithopanspermia Ian von Hegner To cite this version: Ian von Hegner. Evolutionary processes transpiring in the stages of lithopanspermia. 2020. hal- 02548882v2 HAL Id: hal-02548882 https://hal.archives-ouvertes.fr/hal-02548882v2 Preprint submitted on 5 Aug 2020 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. HAL archives-ouvertes.fr | CCSD, April 2020. Evolutionary processes transpiring in the stages of lithopanspermia Ian von Hegner Aarhus University Abstract Lithopanspermia is a theory proposing a natural exchange of organisms between solar system bodies as a result of asteroidal or cometary impactors. Research has examined not only the physics of the stages themselves but also the survival probabilities for life in each stage. However, although life is the primary factor of interest in lithopanspermia, this life is mainly treated as a passive cargo. Life, however, does not merely passively receive an onslaught of stress from surroundings; instead, it reacts. Thus, planetary ejection, interplanetary transport, and planetary entry are only the first three factors in the equation. The other factors are the quality, quantity, and evolutionary strategy of the transported organisms. -
{Download PDF} Feynman
FEYNMAN PDF, EPUB, EBOOK Jim Ottaviani | 272 pages | 13 May 2013 | Roaring Brook Press | 9781596438279 | English | New Milford, United States The Feynman Technique: A Beginner's Guide to Learning Fast While complex, subject-specific jargon sounds cool, it confuses people and urges them to stop paying attention. Replace technical terms with simpler words, and think of how you could explain your lesson to a child. Children are not able to understand jargon or dense vocabulary. His charts were able to simply explain things that other scientists took hours to lecture students on in an attempt to teach them. If a concept is highly technical or complicated, analogies are also a good way to simplify them. Analogies are the foundation of learning from experience, and they work because they make use of your brain's natural inclination to match patterns. Analogies influence what you perceive and remember, and help you process information more easily because you associate it with things you already know. These mental shortcuts are useful methods of processing new and unfamiliar information and help people understand, organize, and comprehend incoming information. One example of an analogy created by Feynman encapsulates the power of his technique. He was able to take a question regarding human existence and simplify it into a simple sentence that even a middle-schooler could understand. Feynman said:. Here, Feynman is saying that if you don't know anything about physics, the most important concept to understand is that everything is composed of atoms. In one sentence, he communicates the fundamental existence of the universe. -
The History and Impact of the CNO Cycles in Nuclear Astrophysics
Phys. Perspect. 20 (2018) 124–158 Ó 2018 Springer International Publishing AG, part of Springer Nature 1422-6944/18/010124-35 https://doi.org/10.1007/s00016-018-0216-0 Physics in Perspective The History and Impact of the CNO Cycles in Nuclear Astrophysics Michael Wiescher* The carbon cycle, or Bethe-Weizsa¨cker cycle, plays an important role in astrophysics as one of the most important energy sources for quiescent and explosive hydrogen burning in stars. This paper presents the intellectual and historical background of the idea of the correlation between stellar energy production and the synthesis of the chemical elements in stars on the example of this cycle. In particular, it addresses the contributions of Carl Friedrich von Weizsa¨cker and Hans Bethe, who provided the first predictions of the carbon cycle. Further, the experimental verification of the predicted process as it developed over the following decades is discussed, as well as the extension of the initial carbon cycle to the carbon- nitrogen-oxygen (CNO) multi-cycles and the hot CNO cycles. This development emerged from the detailed experimental studies of the associated nuclear reactions over more than seven decades. Finally, the impact of the experimental and theoretical results on our present understanding of hydrogen burning in different stellar environments is presented, as well as the impact on our understanding of the chemical evolution of our universe. Key words: Carl Friedrich von Weizsa¨cker; Hans Bethe; Carbon cycle; CNO cycle. Introduction The energy source of the sun and all other stars became a topic of great interests in the physics community in the second half of the nineteenth century. -
Viruses, ET and the Octopus from Space: the Return of | Cosmos 26/04/2018, 4:37 AM
Viruses, ET and the octopus from space: the return of | Cosmos 26/04/2018, 4:37 AM Viruses, ET and the octopus from space: the return of panspermia A major paper revives the oft-mocked theory that life on Earth began in a rain of cosmic microbes. Stephen Fleischfresser reports. The search for ET, say researchers, could start and end with the octopus. CREDIT: VIZERSKAYA/GETTY IMAGES The peer-reviewed journal Progress in Biophysics and Molecular Biology recently published a most remarkable scientific paper[1]. With 33 authors from a wide range of reputable universities and research institutes, the paper makes a seemingly incredible claim. https://cosmosmagazine.com/biology/viruses-et-and-the-octopus-from-space-the-return-of-panspermia Page 1 of 14 Viruses, ET and the octopus from space: the return of | Cosmos 26/04/2018, 4:37 AM A claim that if true, would have the most profound consequences for our understanding of the universe. Life, the paper argues, did not originate on the planet Earth. The response? Near silence. The reasons for this are as fascinating as the evidence and claims advanced by the paper itself. Entitled Cause of the Cambrian Explosion – Terrestrial or Cosmic?, the publication revives a controversial idea concerning the origin of life, an idea stretching back to Ancient Greece, known as panspermia. The scientific orthodoxy concerning the origin of life is called abiogenesis[2]. This suggests that at some point in the earth’s early history, conditions were favourable for the creation of complex organic chemistry that, in turn, led to the self-organisation of the first primitive life forms. -
Feynman Ebook Free Download
FEYNMAN PDF, EPUB, EBOOK Jim Ottaviani | 272 pages | 13 May 2013 | Roaring Brook Press | 9781596438279 | English | New Milford, United States Feynman PDF Book Los Angeles Magazine. Her brother died in at Not exactly. As a child, he had a talent for engineering, maintained an experimental laboratory in his home, and delighted in repairing radios. For free fields with a quadratic action, the probability distribution is a high-dimensional Gaussian, and the statistical average is given by an explicit formula. The particles are represented by the lines of the diagram, which can be squiggly or straight, with an arrow or without, depending on the type of particle. Instead, he used verbal communication as the foundation for the majority of his published works. Real Time Opera. So I manufacture a quarter-size lathe; I manufacture quarter-size tools; and I make, at the one-quarter scale, still another set of hands again relatively one-quarter size! The immense brightness of the explosion made him duck to the truck's floor, where he saw a temporary "purple splotch" afterimage. An interlocutory decree of divorce was entered on June 19, , on the grounds of "extreme cruelty". Wilson , who was working on means to produce enriched uranium for use in an atomic bomb , as part of what would become the Manhattan Project. In the Abelian case, the determinant for covariant gauges does not depend on A , so the ghosts do not contribute to the connected diagrams. Feynman seemed to possess a frightening ease with the substance behind the equations, like Einstein at the same age, like the Soviet physicist Lev Landau —but few others. -
The Dissipative Photochemical Origin of Life: UVC Abiogenesis of Adenine
entropy Article The Dissipative Photochemical Origin of Life: UVC Abiogenesis of Adenine Karo Michaelian Department of Nuclear Physics and Applications of Radiation, Instituto de Física, Universidad Nacional Autónoma de México, Circuito Interior de la Investigación Científica, Cuidad Universitaria, Mexico City, C.P. 04510, Mexico; karo@fisica.unam.mx Abstract: The non-equilibrium thermodynamics and the photochemical reaction mechanisms are described which may have been involved in the dissipative structuring, proliferation and complex- ation of the fundamental molecules of life from simpler and more common precursors under the UVC photon flux prevalent at the Earth’s surface at the origin of life. Dissipative structuring of the fundamental molecules is evidenced by their strong and broad wavelength absorption bands in the UVC and rapid radiationless deexcitation. Proliferation arises from the auto- and cross-catalytic nature of the intermediate products. Inherent non-linearity gives rise to numerous stationary states permitting the system to evolve, on amplification of a fluctuation, towards concentration profiles providing generally greater photon dissipation through a thermodynamic selection of dissipative efficacy. An example is given of photochemical dissipative abiogenesis of adenine from the precursor HCN in water solvent within a fatty acid vesicle floating on a hot ocean surface and driven far from equilibrium by the incident UVC light. The kinetic equations for the photochemical reactions with diffusion are resolved under different environmental conditions and the results analyzed within the framework of non-linear Classical Irreversible Thermodynamic theory. Keywords: origin of life; dissipative structuring; prebiotic chemistry; abiogenesis; adenine; organic molecules; non-equilibrium thermodynamics; photochemical reactions Citation: Michaelian, K. The Dissipative Photochemical Origin of MSC: 92-10; 92C05; 92C15; 92C40; 92C45; 80Axx; 82Cxx Life: UVC Abiogenesis of Adenine. -
IEEE NTC Newsletter
Inside This Issue: • IEEE-NTC elected President and Officers • Nobel Prize for 2018 in Science • Distinguished Lecturers • T-Nano Best Paper Award 2017 • Conferences in Focus Special points of interest: • Prof. Toshio Fukuda—elected as the IEEE President elect 2019-20. • The inventor of Optical Tweezers got Nobel Award in Physics. • IEEE-NTC Facebook page received overwhelmed support and crossed 13,000! For more details and updates visit IEEE—Nanotechnology Council’s Official website: https://ieeenano.org/. Deadline Extended for Call for Nominations for 2019 IEEE Nanotechnology Distinguished Lecturers The deadline for submission of nominations for the 2019 IEEE Nanotechnology Distinguished Lecturers has been extended to 31 October 2018. The term for the Lecturers is from January 1 until December 31 of 2019. The Lecturers serve for a one year term, and may be reappointed for one additional year. See https://ieeenano.org/call-for-nominations-2019-ieee-nanotechnology-distinguished- lecturers/ for details. Editor's Note I am delighted to bring you the newsletter for the quarter ending October-2018. This issue brings you the latest updates and activities in the IEEE-NTC community, with a new President-Elect 2019 and other NTC officers has been elected with more details are provided in the Newsletter. I am also extremely proud to share that the IEEE NTC is currently the largest IEEE council with more than 7000 members of established and young researchers. I hope you enjoy this issue and do let us know if there is any topic you’d like to see covered in the future issue. Jr-Hau He King Abdullah University of Science and Technology EiC Newsletter & Web Content Announcement of newly elected IEEE President-elect (2020-21) Congratulations to the founding President of IEEE Nanotechnology Council (2004-2005, 2002-2003), Professor Toshio Fukuda on being elected IEEE President-Elect, 2019. -
How Science Youtubers Become Experts
Munich Center for Technology in Society (MCTS) „Don’t Act Like a Teacher” – How Science YouTubers become Experts Andrea Geipel Vollständiger Abdruck der von der promotionsführenden Einrichtung Munich Center for Technology in Society (MCTS) der Technischen Universität München zur Erlangung des akademischen Grades eines Doktors der Philosophie (Dr. phil.) genehmigten Dissertation. Vorsitzende: Prof. Dr. Karin Zachmann Prüfende der Dissertation: 1. Priv.-Doz. Dr. Jan-Hendrik Passoth 2. Prof. Dr. Sabine Maasen 3. Prof. Dr. Massimiano Bucchi Die Dissertation wurde am 06.10.2020 bei der Technischen Universität München eingereicht und durch die promotionsführende Einrichtung Munich Center for Technology in Society (MCTS) am 01.02.2021 angenommen. “Don’t Act Like a Teacher” How Science YouTubers become Experts Andrea Geipel Dissertation zur Erlangung des Grades Doktor der Philosophie (phil.) Acknowledgements The decision to start a dissertation at the Munich Center for Technology in Society (MCTS) at the Technische Universität München in 2015 presented me with new and exciting challenges. I am very grateful that Prof. Sabine Maasen believed in me being able to master the transition from Sport Science to Science and Technology Studies. Especially in the beginning, she supported me in refining my topic and helped me to find my way in a new discipline. During the first three years, a position at MCTS in the digital|media|lab under the direction of PD Dr. Jan-Hendrik Passoth allowed me to pursue my dissertation with sufficient time and the necessary collegial and infrastructural support. As my supervisor, Jan-Hendrik Passoth always encouraged me to find my own way in applying methods and integrating theories. -
The Current State of Science Journalism in South Africa: Perspectives of Industry Insiders
The current state of science journalism in South Africa: Perspectives of industry insiders by Eleanor van Zuydam Thesis presented in partial fulfilment of the requirements for the degree of Master of Arts (Journalism) at Stellenbosch University Department of Journalism Faculty of Arts and Social Sciences Supervisor: Professor George Claassen Date: April 2019 Stellenbosch University https://scholar.sun.ac.za Declaration By submitting this thesis electronically, I declare that the entirety of the work contained therein is my own, original work, that I am the owner of the copyright thereof (unless to the extent explicitly otherwise stated) and that I have not previously in its entirety or in part submitted it for obtaining any qualification. Date: April 2019 Copyright © 2019 Stellenbosch University All rights reserved ii Stellenbosch University https://scholar.sun.ac.za I, the undersigned, hereby declare that the work contained in this thesis is my own original work and that I have not previously in its entirety or in part, submitted it at any university for a degree. Signature: Date: Eleanor van Zuydam April 2019 iii Stellenbosch University https://scholar.sun.ac.za Abstract Science news reporting in the South African media does not enjoy the same status as other beats such as politics, sport and business. While extensive research has been conducted into the importance and quality of science journalism in South Africa, on the African continent and globally, current research regarding the personal experiences and perceptions of science journalists in South Africa is in short supply. This study examines the current state of science journalism in South Africa, according to industry insiders.