Quantum Theory Developments* 1N Chemistry
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Autonomy and Automation Computational Modeling, Reduction, and Explanation in Quantum Chemistry Johannes Lenhard, Bielefeld Univ
Autonomy and Automation Computational modeling, reduction, and explanation in quantum chemistry Johannes Lenhard, Bielefeld University preprint abstract This paper discusses how computational modeling combines the autonomy of models with the automation of computational procedures. In particular, the case of ab initio methods in quantum chemistry will be investigated to draw two lessons from the analysis of computational modeling. The first belongs to general philosophy of science: Computational modeling faces a trade-off and enlarges predictive force at the cost of explanatory force. The other lesson is about the philosophy of chemistry: The methodology of computational modeling puts into doubt claims about the reduction of chemistry to physics. 1. Introduction In philosophy of science, there is a lively debate about the role and characteristics of models. The present paper wants to make a contribution to this debate about computational modeling in particular.1 Although there is agreement about the importance of computers in recent science, often their part is seen as merely accelerating computations. Of course, speed is a critical issue in practices of computation, because it restricts or enlarges the range of tractability for computational strategies.2 However, it will be argued in this paper that the conception of computational modeling, is not merely a matter of speed, i.e., not only amplifying already existing approaches, but has much wider philosophical significance. 1 There may be considerable overlap with the issue of simulation, but the argumentation of this paper does not depend on this part of terminology. 2 This has been aptly expressed in the part of Paul Humphreys’ book (2004) that deals with computational science. -
April 17-19, 2018 the 2018 Franklin Institute Laureates the 2018 Franklin Institute AWARDS CONVOCATION APRIL 17–19, 2018
april 17-19, 2018 The 2018 Franklin Institute Laureates The 2018 Franklin Institute AWARDS CONVOCATION APRIL 17–19, 2018 Welcome to The Franklin Institute Awards, the a range of disciplines. The week culminates in a grand United States’ oldest comprehensive science and medaling ceremony, befitting the distinction of this technology awards program. Each year, the Institute historic awards program. celebrates extraordinary people who are shaping our In this convocation book, you will find a schedule of world through their groundbreaking achievements these events and biographies of our 2018 laureates. in science, engineering, and business. They stand as We invite you to read about each one and to attend modern-day exemplars of our namesake, Benjamin the events to learn even more. Unless noted otherwise, Franklin, whose impact as a statesman, scientist, all events are free, open to the public, and located in inventor, and humanitarian remains unmatched Philadelphia, Pennsylvania. in American history. Along with our laureates, we celebrate his legacy, which has fueled the Institute’s We hope this year’s remarkable class of laureates mission since its inception in 1824. sparks your curiosity as much as they have ours. We look forward to seeing you during The Franklin From sparking a gene editing revolution to saving Institute Awards Week. a technology giant, from making strides toward a unified theory to discovering the flow in everything, from finding clues to climate change deep in our forests to seeing the future in a terahertz wave, and from enabling us to unplug to connecting us with the III world, this year’s Franklin Institute laureates personify the trailblazing spirit so crucial to our future with its many challenges and opportunities. -
UC San Diego UC San Diego Electronic Theses and Dissertations
UC San Diego UC San Diego Electronic Theses and Dissertations Title The new prophet : Harold C. Urey, scientist, atheist, and defender of religion Permalink https://escholarship.org/uc/item/3j80v92j Author Shindell, Matthew Benjamin Publication Date 2011 Peer reviewed|Thesis/dissertation eScholarship.org Powered by the California Digital Library University of California UNIVERSITY OF CALIFORNIA, SAN DIEGO The New Prophet: Harold C. Urey, Scientist, Atheist, and Defender of Religion A dissertation submitted in partial satisfaction of the requirements for the degree Doctor of Philosophy in History (Science Studies) by Matthew Benjamin Shindell Committee in charge: Professor Naomi Oreskes, Chair Professor Robert Edelman Professor Martha Lampland Professor Charles Thorpe Professor Robert Westman 2011 Copyright Matthew Benjamin Shindell, 2011 All rights reserved. The Dissertation of Matthew Benjamin Shindell is approved, and it is acceptable in quality and form for publication on microfilm and electronically: ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ ___________________________________________________________________ Chair University of California, San Diego 2011 iii TABLE OF CONTENTS Signature Page……………………………………………………………………...... iii Table of Contents……………………………………………………………………. iv Acknowledgements…………………………………………………………………. -
From Physical Chemistry to Chemical Physics, 1913-1941
International Workshop on the History of Chemistry 2015 Tokyo From Physical Chemistry to Chemical Physics, 1913-1941 Jeremiah James Ludwig-Maximillian University, Munich, Germany There has never been one unique name for the intersection of chemistry and physics. Nor has it ever been defined by a single, stable set of methods. Nevertheless, it is possible and arguably rewarding to distinguish changes in the constellation of terms and techniques that have defined the intersection over the years. I will speak today about one such change, the advent and ascendancy of chemical physics in the interwar period. When the young Friedrich Wilhelm Ostwald first began to formulate his campaign for “physical chemistry” in 1877, he used the term almost interchangeably with two others, “general chemistry” and “theoretical chemistry.” According to his vision of what would soon become a new chemical discipline, physical chemistry would investigate and formulate the general principles that underlie all chemical reactions and phenomena. The primary strategy that he and his allies used to generate these principles was to formulate mathematical “laws” or “rules” generalizing the results of numerous experiments, often performed using measuring apparatus borrowed from physics. Their main fields of inquiry were thermochemistry and solution theory, and they avoided and often openly maligned speculations regarding structures or mechanisms that might underlie the macroscopic regularities embodied in their laws.1 In the first decades of the 20th-century, the modern atomic theory was firmly established, and with only a slight delay, the methods of 19th-century physical chemistry lost a considerable proportion of their audience. Theories relying upon atomistic thinking began to reshape the disciplinary intersections of chemistry and physics, and by the end of the 1930s, cutting-edge research into the general principles of chemistry looked quite different than it had at the turn of the century. -
Supplementary Figure 1: Interconnected Multiplex with Six Nodes in Two Layers (A and D) and Corresponding Aggregated Networks (B and E)
Supplementary Figure 1: Interconnected multiplex with six nodes in two layers (A and D) and corresponding aggregated networks (B and E). The nodes are ranked by their eigenvector centrality in each layer separately, in the aggregated and in the whole interconnected structure (C and F). Case A, B and C. Nodes 1 and 3 have a key role in the multilayer, being bridges between the two layers. In a collaboration network they would represent scientists working on two different research areas who allow information to flow from one subject to the other. While nodes 1 and 3 gain centrality from their connections to \hubs" on different layers, they also gain centrality from their own counterparts in other layers, making them important in the multilayer network. In the aggregated network their versatility disappears, because the information is washed out by projecting on a single layer, where nodes 2 and 6 are still \hubs" but it is not possible to capture the importance of nodes 1 and 3 in bridging different areas. Case D, E and F. This example shows how aggregating the full information on a single network introduces a spurious symmetry between nodes 2, 3, 4 and 6 that is not present in the multilayer, except for 2 and 4. The resulting score in the aggregate is not able to capture the difference between these nodes (corresponding to a degeneration in the eigenspace) while it is evident that, for instance, node 6 is more central than node 3 because of its direct connection to node 1 { the \hub" { in layer 1. -
Theory and Experiment in the Quantum-Relativity Revolution
Theory and Experiment in the Quantum-Relativity Revolution expanded version of lecture presented at American Physical Society meeting, 2/14/10 (Abraham Pais History of Physics Prize for 2009) by Stephen G. Brush* Abstract Does new scientific knowledge come from theory (whose predictions are confirmed by experiment) or from experiment (whose results are explained by theory)? Either can happen, depending on whether theory is ahead of experiment or experiment is ahead of theory at a particular time. In the first case, new theoretical hypotheses are made and their predictions are tested by experiments. But even when the predictions are successful, we can’t be sure that some other hypothesis might not have produced the same prediction. In the second case, as in a detective story, there are already enough facts, but several theories have failed to explain them. When a new hypothesis plausibly explains all of the facts, it may be quickly accepted before any further experiments are done. In the quantum-relativity revolution there are examples of both situations. Because of the two-stage development of both relativity (“special,” then “general”) and quantum theory (“old,” then “quantum mechanics”) in the period 1905-1930, we can make a double comparison of acceptance by prediction and by explanation. A curious anti- symmetry is revealed and discussed. _____________ *Distinguished University Professor (Emeritus) of the History of Science, University of Maryland. Home address: 108 Meadowlark Terrace, Glen Mills, PA 19342. Comments welcome. 1 “Science walks forward on two feet, namely theory and experiment. ... Sometimes it is only one foot which is put forward first, sometimes the other, but continuous progress is only made by the use of both – by theorizing and then testing, or by finding new relations in the process of experimenting and then bringing the theoretical foot up and pushing it on beyond, and so on in unending alterations.” Robert A. -
Communications-Mathematics and Applied Mathematics/Download/8110
A Mathematician's Journey to the Edge of the Universe "The only true wisdom is in knowing you know nothing." ― Socrates Manjunath.R #16/1, 8th Main Road, Shivanagar, Rajajinagar, Bangalore560010, Karnataka, India *Corresponding Author Email: [email protected] *Website: http://www.myw3schools.com/ A Mathematician's Journey to the Edge of the Universe What’s the Ultimate Question? Since the dawn of the history of science from Copernicus (who took the details of Ptolemy, and found a way to look at the same construction from a slightly different perspective and discover that the Earth is not the center of the universe) and Galileo to the present, we (a hoard of talking monkeys who's consciousness is from a collection of connected neurons − hammering away on typewriters and by pure chance eventually ranging the values for the (fundamental) numbers that would allow the development of any form of intelligent life) have gazed at the stars and attempted to chart the heavens and still discovering the fundamental laws of nature often get asked: What is Dark Matter? ... What is Dark Energy? ... What Came Before the Big Bang? ... What's Inside a Black Hole? ... Will the universe continue expanding? Will it just stop or even begin to contract? Are We Alone? Beginning at Stonehenge and ending with the current crisis in String Theory, the story of this eternal question to uncover the mysteries of the universe describes a narrative that includes some of the greatest discoveries of all time and leading personalities, including Aristotle, Johannes Kepler, and Isaac Newton, and the rise to the modern era of Einstein, Eddington, and Hawking. -
Edward B. Van Vleck 1863‐1943
Remembering Van: Three Madison families and other tales “Van had many enthusiasms and loyalties, but none exceeded those he felt for the University of Wisconsin and its home, Madison.” 1 Charles Van Hise Born in 1857, Charles Van Hise was a distinguished geologist who had been elected to the National Academy of Sciences in 1902. In 1903, he was named President of the University of Wisconsin 2 In 1904, Van Hise recruited Charles Russell Bardeen, a member of the first class to graduate of the Johns Hopkins Medical School, to found a medical school at the University of Wisconsin John Bardeen is at the right hand end. His grandfather, Charles W Bardeen, is second from the left. 3 Charles Sumner Slichter 1864-1946 In 1906, Van Hise appointed Charles S. Slichter head of the math department. An applied mathematician with interests in flow of liquids through porous media, Slichter realized the department needed to strengthen the faculty in pure mathematics. 4 Edward B. Van Vleck 1863‐1943 Edward B Van Vleck, had earned a PhD in mathematics at Gottingen in1893, and was a member of the National Academy of Sciences. Slichter’s first action as department head was to recruit Van Vleck to bring strength in pure mathematics. 5 John Hasbrouck Van Vleck was born in 1899. His interest in trains began at a early age. Van attended his first Wisconsin football game at age 10.(Wisconsin vs Minnesota) It was the first game at which the band played the famous song “On Wisconsin”. As an undergraduate at Wisconsin, Van played flute In the band. -
Report and Opinion 2016;8(6) 1
Report and Opinion 2016;8(6) http://www.sciencepub.net/report Beyond Einstein and Newton: A Scientific Odyssey Through Creation, Higher Dimensions, And The Cosmos Manjunath R Independent Researcher #16/1, 8 Th Main Road, Shivanagar, Rajajinagar, Bangalore: 560010, Karnataka, India [email protected], [email protected] “There is nothing new to be discovered in physics now. All that remains is more and more precise measurement.” : Lord Kelvin Abstract: General public regards science as a beautiful truth. But it is absolutely-absolutely false. Science has fatal limitations. The whole the scientific community is ignorant about it. It is strange that scientists are not raising the issues. Science means truth, and scientists are proponents of the truth. But they are teaching incorrect ideas to children (upcoming scientists) in schools /colleges etc. One who will raise the issue will face unprecedented initial criticism. Anyone can read the book and find out the truth. It is open to everyone. [Manjunath R. Beyond Einstein and Newton: A Scientific Odyssey Through Creation, Higher Dimensions, And The Cosmos. Rep Opinion 2016;8(6):1-81]. ISSN 1553-9873 (print); ISSN 2375-7205 (online). http://www.sciencepub.net/report. 1. doi:10.7537/marsroj08061601. Keywords: Science; Cosmos; Equations; Dimensions; Creation; Big Bang. “But the creative principle resides in Subaltern notable – built on the work of the great mathematics. In a certain sense, therefore, I hold it astronomers Galileo Galilei, Nicolaus Copernicus true that pure thought can -
On the Shoulders of Giants: a Brief History of Physics in Göttingen
1 6 ON THE SHO UL DERS OF G I A NTS : A B RIEF HISTORY OF P HYSI C S IN G Ö TTIN G EN On the Shoulders of Giants: a brief History of Physics in Göttingen 18th and 19th centuries Georg Ch. Lichtenberg (1742-1799) may be considered the fore- under Emil Wiechert (1861-1928), where seismic methods for father of experimental physics in Göttingen. His lectures were the study of the Earth's interior were developed. An institute accompanied by many experiments with equipment which he for applied mathematics and mechanics under the joint direc- had bought privately. To the general public, he is better known torship of the mathematician Carl Runge (1856-1927) (Runge- for his thoughtful and witty aphorisms. Following Lichtenberg, Kutta method) and the pioneer of aerodynamics, or boundary the next physicist of world renown would be Wilhelm Weber layers, Ludwig Prandtl (1875-1953) complemented the range of (1804-1891), a student, coworker and colleague of the „prince institutions related to physics proper. In 1925, Prandtl became of mathematics“ C. F. Gauss, who not only excelled in electro- the director of a newly established Kaiser-Wilhelm-Institute dynamics but fought for his constitutional rights against the for Fluid Dynamics. king of Hannover (1830). After his re-installment as a profes- A new and well-equipped physics building opened at the end sor in 1849, the two Göttingen physics chairs , W. Weber and B. of 1905. After the turn to the 20th century, Walter Kaufmann Listing, approximately corresponded to chairs of experimen- (1871-1947) did precision measurements on the velocity depen- tal and mathematical physics. -
Robert Mulliken and His Influence on Japanese Physical Chemistry
International Workshop on the History of Chemistry 2015 Tokyo Robert Mulliken and His Influence on Japanese Physical Chemistry Noboru Hirota Kyoto University, Japan Introduction Physical Chemistry underwent a transformation from a science based on thermodynamics to one based on quantum mechanics in the 1920s and the early 1930s. Although quantum mechanics was born in Germany and first applied to a chemical problem, understanding of the 1 covalent bonding in H2, by two physicists, Walter Heitler and Fritz London , the transformation in physical chemistry was mainly made in the US; some young American physical chemists were very active in applying quantum mechanics to chemical problems. Most notable among them were three Nobel Prize winning physical chemists, Linus Pauling, Robert Mulliken and Harold Urey. In particular, Linus Pauling and Robert Mulliken played the most important roles in the development of quantum chemistry in the 1920s and the1930s. Both of them started as experimental physical chemists, Pauling as an X-ray crystallographer and Mulliken as a molecular spectroscopist, but they became pioneers in applying quantum mechanics to chemical problems. However, in their endeavors they took different approaches. Pauling advanced valence bond theory, applying it to explain a variety of chemical bonds. His famous book on the nature of chemical bonds was well received by chemists and became a classic.2 On the other hand, Mulliken advanced molecular orbital theory in connection with the interpretation of the electronic spectra of small molecules3. Before World War II Paulings’s valence bond theory was more popular and influential among chemists because of its appeal to chemical intuition. -
The 'Hyperbola of Quantum Chemistry': the Changing Practice and Identity
A S, 60 (2003), 219–247 The ‘Hyperbola of Quantum Chemistry’: the Changing Practice and Identity of a Scientific Discipline in the Early Years of Electronic Digital Computers, 1945–65 B S P NIH History Office, Building 31 Room 5B38, MSC 2092, National Institutes of Health, Bethesda, MD 20892, USA e-mail: [email protected] Received 19 June 2001. Revised paper accepted 15 November 2001 Summary In 1965, John A. Pople presented a paper entitled ‘Two-Dimensional Chart of Quantum Chemistry’ to illustrate the inverse relationship between the sophistica- tion of computational methods and the size of molecules under study. This chart, later called the ‘hyperbola of quantum chemistry’, succinctly summarized the growing tension between the proponents of two different approaches to computa- tion—the ab initio method and semiempirical method—in the early years of electronic digital computers. Examining the development of quantum chemistry after World War II, I focus on the role of computers in shaping disciplinary identity. The availability of high-speed computers in the early 1950s attracted much attention from quantum chemists, and their community took shape through a series of conferences and personal networking. However, this emerging com- munity soon encountered the problem of communication between groups that differed in the degree of reliance they placed on computers. I show the complexity of interactions between computing technology and a scientific discipline, in terms of both forming and splitting the community of quantum chemistry. Contents 1. Introduction ................................................... 219 2. Quantum chemistry before World War II ......................... 220 3. Networking: conferences, information exchange, and a call for computers ....................................................