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Wave Extraction in Numerical Relativity
Doctoral Dissertation Wave Extraction in Numerical Relativity Dissertation zur Erlangung des naturwissenschaftlichen Doktorgrades der Bayrischen Julius-Maximilians-Universitat¨ Wurzburg¨ vorgelegt von Oliver Elbracht aus Warendorf Institut fur¨ Theoretische Physik und Astrophysik Fakultat¨ fur¨ Physik und Astronomie Julius-Maximilians-Universitat¨ Wurzburg¨ Wurzburg,¨ August 2009 Eingereicht am: 27. August 2009 bei der Fakultat¨ fur¨ Physik und Astronomie 1. Gutachter:Prof.Dr.Karl Mannheim 2. Gutachter:Prof.Dr.Thomas Trefzger 3. Gutachter:- der Dissertation. 1. Prufer¨ :Prof.Dr.Karl Mannheim 2. Prufer¨ :Prof.Dr.Thomas Trefzger 3. Prufer¨ :Prof.Dr.Thorsten Ohl im Promotionskolloquium. Tag des Promotionskolloquiums: 26. November 2009 Doktorurkunde ausgehandigt¨ am: Gewidmet meinen Eltern, Gertrud und Peter, f¨urall ihre Liebe und Unterst¨utzung. To my parents Gertrud and Peter, for all their love, encouragement and support. Wave Extraction in Numerical Relativity Abstract This work focuses on a fundamental problem in modern numerical rela- tivity: Extracting gravitational waves in a coordinate and gauge independent way to nourish a unique and physically meaningful expression. We adopt a new procedure to extract the physically relevant quantities from the numerically evolved space-time. We introduce a general canonical form for the Weyl scalars in terms of fundamental space-time invariants, and demonstrate how this ap- proach supersedes the explicit definition of a particular null tetrad. As a second objective, we further characterize a particular sub-class of tetrads in the Newman-Penrose formalism: the transverse frames. We establish a new connection between the two major frames for wave extraction: namely the Gram-Schmidt frame, and the quasi-Kinnersley frame. Finally, we study how the expressions for the Weyl scalars depend on the tetrad we choose, in a space-time containing distorted black holes. -
Einstein's Mistakes
Einstein’s Mistakes Einstein was the greatest genius of the Twentieth Century, but his discoveries were blighted with mistakes. The Human Failing of Genius. 1 PART 1 An evaluation of the man Here, Einstein grows up, his thinking evolves, and many quotations from him are listed. Albert Einstein (1879-1955) Einstein at 14 Einstein at 26 Einstein at 42 3 Albert Einstein (1879-1955) Einstein at age 61 (1940) 4 Albert Einstein (1879-1955) Born in Ulm, Swabian region of Southern Germany. From a Jewish merchant family. Had a sister Maja. Family rejected Jewish customs. Did not inherit any mathematical talent. Inherited stubbornness, Inherited a roguish sense of humor, An inclination to mysticism, And a habit of grüblen or protracted, agonizing “brooding” over whatever was on its mind. Leading to the thought experiment. 5 Portrait in 1947 – age 68, and his habit of agonizing brooding over whatever was on its mind. He was in Princeton, NJ, USA. 6 Einstein the mystic •“Everyone who is seriously involved in pursuit of science becomes convinced that a spirit is manifest in the laws of the universe, one that is vastly superior to that of man..” •“When I assess a theory, I ask myself, if I was God, would I have arranged the universe that way?” •His roguish sense of humor was always there. •When asked what will be his reactions to observational evidence against the bending of light predicted by his general theory of relativity, he said: •”Then I would feel sorry for the Good Lord. The theory is correct anyway.” 7 Einstein: Mathematics •More quotations from Einstein: •“How it is possible that mathematics, a product of human thought that is independent of experience, fits so excellently the objects of physical reality?” •Questions asked by many people and Einstein: •“Is God a mathematician?” •His conclusion: •“ The Lord is cunning, but not malicious.” 8 Einstein the Stubborn Mystic “What interests me is whether God had any choice in the creation of the world” Some broadcasters expunged the comment from the soundtrack because they thought it was blasphemous. -
Von Richthofen, Einstein and the AGA Estimating Achievement from Fame
Von Richthofen, Einstein and the AGA Estimating achievement from fame Every schoolboy has heard of Einstein; fewer have heard of Antoine Becquerel; almost nobody has heard of Nils Dalén. Yet they all won Nobel Prizes for Physics. Can we gauge a scientist’s achievements by his or her fame? If so, how? And how do fighter pilots help? Mikhail Simkin and Vwani Roychowdhury look for the linkages. “It was a famous victory.” We instinctively rank the had published. However, in 2001–2002 popular French achievements of great men and women by how famous TV presenters Igor and Grichka Bogdanoff published they are. But is instinct enough? And how exactly does a great man’s fame relate to the greatness of his achieve- ment? Some achievements are easy to quantify. Such is the case with fighter pilots of the First World War. Their achievements can be easily measured and ranked, in terms of their victories – the number of enemy planes they shot down. These aces achieved varying degrees of fame, which have lasted down to the internet age. A few years ago we compared1 the fame of First World War fighter pilot aces (measured in Google hits) with their achievement (measured in victories); and we found that We can estimate fame grows exponentially with achievement. fame from Google; Is the same true in other areas of excellence? Bagrow et al. have studied the relationship between can this tell us 2 achievement and fame for physicists . The relationship Manfred von Richthofen (in cockpit) with members of his so- about actual they found was linear. -
Dr. Abraham Pais Dr. Pais Was Born in Amsterdam on May 19, 1918. He
Director's Office: Faculty Files: Box 25: Pais, Abraham, Permanent Member From the Shelby White and Leon Levy Archives Center, Institute for Advanced Study, Princeton, NJ, USA Dr. Abraham Pais Dr. Pais was born i n Amsterdam on May 19, 1918. He obtained his Doctor's Degree at the University of Utrecht in 1941. During the years of the occupation, he continued to work under conditions of great difficulty, and the year after the war he was an assistant at the Insti- tute of Theoretical Physics in Copenhagen, In the fall of 1946, Dr. Pais came to the Institute for Advanced Study. ~he record of Dr. Pais' work in the last decade is almost a history of the efforts to clar ify our understanding of basic atomic theory and of the nature of elementary particles. Pais first proposed the compensa- tion theories of elenientary particles, and much of his work tas been devoted. to exploring the success and limitations of these theories, and indicating the radical character of the revisions which will be needed before they can successfully describe the sub-atomic world. Pais has made important contri- butions to nuclear theory and to electrodynamics . He is one of the few young theoretical physicists who within the last decade have enriched our understanding of physics. Statement prepared by J . R. Oppenheim.er Enclosure: Bibliography of papers by Dr. Pais Director's Office: Faculty Files: Box 25: Pais, Abraham, Permanent Member From the Shelby White and Leon Levy Archives Center, Institute for Advanced Study, Princeton, NJ, USA PUBLICATIONS OF ABRAHllJ~ PAIS The ener gy moment um tensor in projective r elativity theor y, Physi ca 8 (1941), 1137-116o . -
Detection of a Strange Particle
10 extraordinary papers Within days, Watson and Crick had built a identify the full set of codons was completed in forensics, and research into more-futuristic new model of DNA from metal parts. Wilkins by 1966, with Har Gobind Khorana contributing applications, such as DNA-based computing, immediately accepted that it was correct. It the sequences of bases in several codons from is well advanced. was agreed between the two groups that they his experiments with synthetic polynucleotides Paradoxically, Watson and Crick’s iconic would publish three papers simultaneously in (see go.nature.com/2hebk3k). structure has also made it possible to recog- Nature, with the King’s researchers comment- With Fred Sanger and colleagues’ publica- nize the shortcomings of the central dogma, ing on the fit of Watson and Crick’s structure tion16 of an efficient method for sequencing with the discovery of small RNAs that can reg- to the experimental data, and Franklin and DNA in 1977, the way was open for the com- ulate gene expression, and of environmental Gosling publishing Photograph 51 for the plete reading of the genetic information in factors that induce heritable epigenetic first time7,8. any species. The task was completed for the change. No doubt, the concept of the double The Cambridge pair acknowledged in their human genome by 2003, another milestone helix will continue to underpin discoveries in paper that they knew of “the general nature in the history of DNA. biology for decades to come. of the unpublished experimental results and Watson devoted most of the rest of his ideas” of the King’s workers, but it wasn’t until career to education and scientific administra- Georgina Ferry is a science writer based in The Double Helix, Watson’s explosive account tion as head of the Cold Spring Harbor Labo- Oxford, UK. -
A Measurement of Neutral B Meson Mixing Using Dilepton Events with the BABAR Detector
A measurement of neutral B meson mixing using dilepton events with the BABAR detector Naveen Jeevaka Wickramasinghe Gunawardane Imperial College, London A thesis submitted for the degree of Doctor of Philosophy of the University of London and the Diploma of Imperial College December, 2000 A measurement of neutral B meson mixing using dilepton events with the BABAR detector Naveen Gunawardane Blackett Laboratory Imperial College of Science, Technology and Medicine Prince Consort Road London SW7 2BW December, 2000 ABSTRACT This thesis reports on a measurement of the neutral B meson mixing parameter, ∆md, at the BABAR experiment and the work carried out on the electromagnetic calorimeter (EMC) data acquisition (DAQ) system and simulation software. The BABAR experiment, built at the Stanford Linear Accelerator Centre, uses the PEP-II asymmetric storage ring to make precise measurements in the B meson system. Due to the high beam crossing rates at PEP-II, the DAQ system employed by BABAR plays a very crucial role in the physics potential of the experiment. The inclusion of machine backgrounds noise is an important consideration within the simulation environment. The BABAR event mixing software written for this purpose have the functionality to mix both simulated and real detector backgrounds. Due to the high energy resolution expected from the EMC, a matched digital filter is used. The performance of the filter algorithms could be improved upon by means of a polynomial fit. Application of the fit resulted in a 4-40% improvement in the energy resolution and a 90% improvement in the timing resolution. A dilepton approach was used in the measurement of ∆md where the flavour of the B was tagged using the charge of the lepton. -
Arxiv:1210.3065V1
Neutrino. History of a unique particle S. M. Bilenky Joint Institute for Nuclear Research, Dubna, R-141980, Russia TRIUMF 4004 Wesbrook Mall, Vancouver BC, V6T 2A3 Canada Abstract Neutrinos are the only fundamental fermions which have no elec- tric charges. Because of that neutrinos have no direct electromagnetic interaction and at relatively small energies they can take part only 0 in weak processes with virtual W ± and Z bosons (like β-decay of nuclei, inverse β processν ¯ + p e+n, etc.). Neutrino masses are e → many orders of magnitude smaller than masses of charged leptons and quarks. These two circumstances make neutrinos unique, special par- ticles. The history of the neutrino is very interesting, exciting and instructive. We try here to follow the main stages of the neutrino his- tory starting from the Pauli proposal and finishing with the discovery and study of neutrino oscillations. 1 The idea of neutrino. Pauli Introduction The history of the neutrino started with the famous Pauli letter. The exper- imental data ”forced” Pauli to assume the existence of a new particle which later was called neutrino. The hypothesis of the neutrino allowed Fermi to build the first theory of the β-decay which he considered as a process of a quantum transition of a neutron into a proton with the creation of an electron-(anti)neutrino pair. During many years this was the only experi- arXiv:1210.3065v1 [hep-ph] 10 Oct 2012 mentally studied process in which the neutrino takes part. The main efforts were devoted at that time to the search for a Hamiltonian of the interaction which governs the decay. -
CP Symmetry Violation: the Search for Its Origin.” Reviews of Modern Physics 53 (1981) 373–383
CP SYMMETRY VIOLATION 1 Jonathan L. Rosner The symmetry known as CP is a fundamental relation between matter and antimatter. The discovery of its violation by Christenson, Cronin, Fitch, and Turlay (1964) has given us important insights into the structure of particle interactions and into why the Universe appears to contain more matter than antimatter. In 1928, Paul Dirac predicted that every particle has a corresponding an- tiparticle. If the particle has quantum numbers (intrinsic properties), such as electric charge, the antiparticle will have opposite quantum numbers. Thus, an electron, with charge −|e|, has as its antiparticle a positron, with charge +|e| and the same mass and spin. Some neutral particles, such as the photon, the quantum of radiation, are their own antiparticles. Others, like the neutron, have distinct antiparticles; the neutron carries a quantum number known as baryon number B = 1, and the antineutron has B = –1. (The prefix bary- is Greek for heavy.) The operation of charge reversal, or C, carries a particle into its antiparticle. Many laws of physics are invariant under the C operation; that is, they do arXiv:hep-ph/0109240v2 15 Oct 2001 not change their form, and, consequently, one cannot tell whether one lives in a world made of matter or one made of antimatter. Many equations are also invariant under two other important symmetries: space reflection, or parity, denoted by P, which reverses the direction of all spatial coordinates, and time reversal, denoted by T, which reverses the arrow of time. By observing systems governed by these equations, we cannot tell whether our world is reflected in a mirror or in which direction its clock is running. -
J. Robert Oppenheimer Papers [Finding Aid]. Library of Congress
J. Robert Oppenheimer Papers A Finding Aid to the Collection in the Library of Congress Manuscript Division, Library of Congress Washington, D.C. 2016 Revised 2016 June Contact information: http://hdl.loc.gov/loc.mss/mss.contact Additional search options available at: http://hdl.loc.gov/loc.mss/eadmss.ms998007 LC Online Catalog record: http://lccn.loc.gov/mm77035188 Prepared by Carolyn H. Sung and David Mathisen Revised and expanded by Michael Spangler and Stephen Urgola in 2000, and Michael Folkerts in 2016 Collection Summary Title: J. Robert Oppenheimer Papers Span Dates: 1799-1980 Bulk Dates: (bulk 1947-1967) ID No.: MSS35188 Creator: Oppenheimer, J. Robert, 1904-1967 Extent: 76,450 items ; 301 containers plus 2 classified ; 120.2 linear feet Language: Collection material in English Location: Manuscript Division, Library of Congress, Washington, D.C. Summary: Physicist and director of the Institute for Advanced Study, Princeton, New Jersey. Correspondence, memoranda, speeches, lectures, writings, desk books, lectures, statements, scientific notes, and photographs chiefly comprising Oppenheimer's personal papers while director of the Institute for Advanced Study but reflecting only incidentally his administrative work there. Topics include theoretical physics, development of the atomic bomb, the relationship between government and science, nuclear energy, security, and national loyalty. Selected Search Terms The following terms have been used to index the description of this collection in the Library's online catalog. They are grouped by name of person or organization, by subject or location, and by occupation and listed alphabetically therein. People Bethe, Hans A. (Hans Albrecht), 1906-2005--Correspondence. Birge, Raymond T. (Raymond Thayer), 1887- --Correspondence. -
Introduction String Theory Is a Mystery. It's Supposed to Be The
Copyrighted Material i n T r o D U C T i o n String theory is a mystery. it’s supposed to be the the- ory of everything. But it hasn’t been verified experimen- tally. And it’s so esoteric. it’s all about extra dimensions, quantum fluctuations, and black holes. how can that be the world? Why can’t everything be simpler? String theory is a mystery. its practitioners (of which i am one) admit they don’t understand the theory. But calculation after calculation yields unexpectedly beautiful, connected results. one gets a sense of inevitability from studying string theory. how can this not be the world? how can such deep truths fail to connect to reality? String theory is a mystery. it draws many talented gradu- ate students away from other fascinating topics, like super- conductivity, that already have industrial applications. it attracts media attention like few other fields in science. And it has vociferous detractors who deplore the spread of its influence and dismiss its achievements as unrelated to em- pirical science. Briefly, the claim of string theory is that the fundamental objects that make up all matter are not particles, but strings. Strings are like little rubber bands, but very thin and very strong. An electron is supposed to be actually a string, vibrat- ing and rotating on a length scale too small for us to probe even with the most advanced particle accelerators to date. in Copyrighted Material 2 some versions of string theory, an electron is a closed loop of string. in others, it is a segment of string, with two endpoints. -
James Chadwick and E.S
What is the Universe Made Of? Atoms - Electrons Nucleus - Nucleons Antiparticles And ... http://www.parentcompany.com/creation_explanation/cx6a.htm What Holds it Together? Gravitational Force Electromagnetic Force Strong Force Weak Force Timeline - Ancient 624-547 B.C. Thales of Miletus - water is the basic substance, knew attractive power of magnets and rubbed amber. 580-500 B.C. Pythagoras - Earth spherical, sought mathematical understanding of universe. 500-428 B.C. Anaxagoras changes in matter due to different orderings of indivisible particles (law of the conservation of matter) 484-424 B.C. Empedocles reduced indivisible particles into four elements: earth, air, fire, and water. 460-370 B.C. Democritus All matter is made of indivisible particles called atoms. 384-322 B.C. Aristotle formalized the gathering of scientific knowledge. 310-230 B.C. Aristarchus describes a cosmology identical to that of Copernicus. 287-212 B.C. Archimedes provided the foundations of hydrostatics. 70-147 AD Ptolemy of Alexandria collected the optical knowledge, theory of planetary motion. 1214-1294 AD Roger Bacon To learn the secrets of nature we must first observe. 1473-1543 AD Nicholaus Copernicus The earth revolves around the sun Timeline – Classical Physics 1564-1642 Galileo Galilei - scientifically deduced theories. 1546-1601, Tycho Brahe accurate celestial data to support Copernican system. 1571-1630, Johannes Kepler. theory of elliptical planetary motion 1642-1727 Sir Isaac Newton laws of mechanics explain motion, gravity . 1773-1829 Thomas Young - the wave theory of light and light interference. 1791-1867 Michael Faraday - the electric motor, and electromagnetic induction, electricity and magnetism are related. electrolysis, conservation of energy. -
Halliday & Resnick 9Th Edition Solution Manual
Chapter 44 1. By charge conservation, it is clear that reversing the sign of the pion means we must reverse the sign of the muon. In effect, we are replacing the charged particles by their antiparticles. Less obvious is the fact that we should now put a “bar” over the neutrino (something we should also have done for some of the reactions and decays discussed in Chapters 42 and 43, except that we had not yet learned about antiparticles). To understand the “bar” we refer the reader to the discussion in Section 44-4. The decay of the negative pion is π− →+μ − v. A subscript can be added to the antineutrino to clarify what “type” it is, as discussed in Section 44-4. 2. Since the density of water is ρ = 1000 kg/m3 = 1 kg/L, then the total mass of the pool is ρ = 4.32 × 105 kg, where is the given volume. Now, the fraction of that mass made up by the protons is 10/18 (by counting the protons versus total nucleons in a water molecule). Consequently, if we ignore the effects of neutron decay (neutrons can beta decay into protons) in the interest of making an order-of-magnitude calculation, then the 32 number of particles susceptible to decay via this T1/2 = 10 y half-life is × 5 (10 / 18)M pool (10 / 18)( 4.32 10 kg ) 32 N ==−27 =1.44× 10 . mp 1.67× 10 kg Using Eq. 42-20, we obtain 32 N ln2 ch144.l× 10n 2 R == 32 ≈ 1decay y.