Fundamental Nature of the Fine-Structure Constant Michael Sherbon
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Theoretical Physics
IC/80/166 INTERNATIONAL CENTRE FOR THEORETICAL PHYSICS AW EFFICIENT KORRINGA-KOHN-ROSTOKER METHOD FOR "COMPLEX" LATTICES M. Yussouff and INTERNATIONAL ATOMIC ENERGY R. Zeller AGENCY UNITED NATIONS EDUCATIONAL SCIENTIFIC AND CULTURAL ORGANIZATION 19R0 MIRAMARE-TRIESTE IC/90/166 The well known rapid convergence and precision of the KKR- Green's function method (Korringa 1947, Kohn and Rostocker 1954) International Atomic Energy Agency have made it useful for the calculation of the electronic struc- and United Rations Educational Scientific and Cultural Organization ture of perfect as well as disordered solids (Ham and Segall 1961, IHTEBSATIOHAL CENTRE FOR THEORETICAL PHYSICS Ehrenrelch and Schwartz 1976). Although extensive calculations of this kind exist for cubic crystals (Moruzzi, Janak and Williams 1978), there are so far very few calculations for the equally important class of hexagonal close packed solids. This is due to the computational efforts involved in evaluating the KKR matrix AH EFFICIENT KORRIHGA-KOHH-ROSTOKER METHOD FOR "COMPLEX" LATTICES • elements ATT,{k,E) using the conventional KKR for 'complex' lattices, i.e. crystals with several atoms per unit cell- Some simplifications can be achieved (Bhokare and Yussouff 1972, 1974) for k" vectors International Centre for Theoretical Physics, Trieste, Italy, in symmetry directions but the renewed interest in simplifying the and computations (Segall and Yang 19 80) has arisen in connection with self-consistent calcualtions. Here we describe an efficient modi- R. Zeller Institut fur FeBtkorperforschung der Kernforschungsanlage, fication of the KKR method which is particularly useful for 'complex1 D-5170 Jiilieh, Federal Republic of Germany. lattices. ABSTRACT In our approach, the transformed KKR matrix elements are calcu- We present a modification of the exact KKR-band structure method lated directly using reciprocal space summation. -
|||GET||| Can the Laws of Physics Be Unified? 1St Edition
CAN THE LAWS OF PHYSICS BE UNIFIED? 1ST EDITION DOWNLOAD FREE Paul Langacker | 9781400885503 | | | | | Can the Laws of Physics be Unified? Answer Key. In American physicist Sheldon Glashow proposed that the weak nuclear forceelectricity and magnetism could arise Can the Laws of Physics Be Unified? 1st edition a partially unified electroweak theory. Law II: The alteration of motion is ever proportional to the motive force impress'd; and is made in the direction of the right line in which that force is impress'd. In the s Mendel Sachs proposed a generally covariant field theory that did not require recourse to renormalisation or perturbation theory. Discoveries are made; models, theories, and laws are formulated; and the beauty of the physical universe is made more sublime for the insights gained. Download as PDF Printable version. Lots of equations, but not much detail explaining exactly what they mean, for that some background is needed. I find that literally inconceivable. These laws are Can the Laws of Physics Be Unified? 1st edition systematically to topics such as phase equilibria, chemical reactions, external forces, fluid-fluid surfaces and interfaces, and anisotropic crystal-fluid interfaces. Cohen and A. The physical universe is enormously complex in its detail. One of her daughters also won a Nobel Prize. Archived from the original PDF on 31 March Thank you for posting a review! And, whereas a law is a postulate that forms the foundation of the scientific method, a theory is the end result of that process. I know of none whatsoever. Paul Langacker is senior scientist at Princeton University, visitor at the Institute for Advanced Study in Princeton, and professor emeritus of physics at the University of Pennsylvania. -
Quantum Mechanics from General Relativity : Particle Probability from Interaction Weighting
Annales de la Fondation Louis de Broglie, Volume 24, 1999 25 Quantum Mechanics From General Relativity : Particle Probability from Interaction Weighting Mendel Sachs Department of Physics State University of New York at Bualo ABSTRACT. Discussion is given to the conceptual and mathemat- ical change from the probability calculus of quantum mechanics to a weighting formalism, when the paradigm change takes place from linear quantum mechanics to the nonlinear, holistic eld theory that accompanies general relativity, as a fundamental theory of matter. This is a change from a nondeterministic, linear theory of an open system of ‘particles’ to a deterministic, nonlinear, holistic eld the- ory of the matter of a closed system. RESUM E. On discute le changement conceptuel et mathematique qui fait passer du calcul des probabilites de la mecanique quantique a un formalisme de ponderation, quand on eectue le changement de paradigme substituantalam ecanique quantique lineairelatheorie de champ holistique non lineaire qui est associee alatheorie de la relativitegenerale, prise comme theorie fondamentale de la matiere. Ce changement mene d’une theorie non deterministe et lineaire decrivant un systeme ouvert de ‘particules’ a une theorie de champ holistique, deterministe et non lineaire, de la matiere constituant un systeme ferme. 1. Introduction. In my view, one of the three most important experimental discov- eries of 20th century physics was the wave nature of matter. [The other two were 1) blackbody radiation and 2) the bending of a beam of s- tarlight as it propagates past the vicinity of the sun]. The wave nature of matter was predicted in the pioneering theoretical studies of L. -
Dirac's Fine-Structure Formula for an “Abnormally High”
Dirac’s fine-structure formula for an “abnormally high” nuclear charge The solution of an old riddle A. LOINGER Dipartimento di Fisica dell’Università di Milano Via Celoria, 16 − 20133 Milano, Italy Summary. − In Dirac’s fine-structure formula for the hydrogenlike atoms a critical role is played by the square root of the following expression: the unity minus the square of the product of the atomic number by the fine-structure constant (which is approximately equal to 1/137). Indeed, for a fictitious, ideal nucleus for which the above product is greater than or equal to one, the mentioned square root becomes imaginary, or zero. I prove in this Note that the origin of such theoretical “breaking down” is quite simple and is inherent in the special theory of relativity of classical physics. PACS 11.10 − Relativistic wave equations; 03.65 – Semiclassical theories and applications. 1. − The problem As is well known, Dirac’s fine-structure formula for the energy of an electron in the Coulomb field generated by a fixed nuclear charge Ze is as follows: −1 2 2 2 E Z α (1.1) = 1+ , 2 2 m0c 2 2 2 1 2 []nr + (κ − Z α ) 2 where: E = W + m0c is the relativistic total energy; m0 is the rest-mass of the 2 electron; α := e (hc) is the fine-structure constant; nr = 0,1,2,3,... is the radial quantum number; κ = ±1,±2,±3,... is the auxiliary quantum number (according to a Weylian terminology); when nr = 0 , the quantum κ takes only the positive values [1]. -
Two Photon Processes Within the Hyperfine Structure of Hydrogen
University of Windsor Scholarship at UWindsor Electronic Theses and Dissertations Theses, Dissertations, and Major Papers 12-10-2018 Two Photon Processes within the Hyperfine Structure of Hydrogen Spencer Dylan Percy University of Windsor Follow this and additional works at: https://scholar.uwindsor.ca/etd Recommended Citation Percy, Spencer Dylan, "Two Photon Processes within the Hyperfine Structure of Hydrogen" (2018). Electronic Theses and Dissertations. 7622. https://scholar.uwindsor.ca/etd/7622 This online database contains the full-text of PhD dissertations and Masters’ theses of University of Windsor students from 1954 forward. These documents are made available for personal study and research purposes only, in accordance with the Canadian Copyright Act and the Creative Commons license—CC BY-NC-ND (Attribution, Non-Commercial, No Derivative Works). Under this license, works must always be attributed to the copyright holder (original author), cannot be used for any commercial purposes, and may not be altered. Any other use would require the permission of the copyright holder. Students may inquire about withdrawing their dissertation and/or thesis from this database. For additional inquiries, please contact the repository administrator via email ([email protected]) or by telephone at 519-253-3000ext. 3208. Two Photon Processes within the Hyperfine Structure of Hydrogen by Spencer Percy A Thesis Submitted to the Faculty of Graduate Studies through the Department of Physics in Partial Fulfillment of the Requirements for the Degree of Master of Science at the University of Windsor Windsor, Ontario, Canada c 2018 Spencer Percy Two Photon Processes in the Hyperfine Structure of Hydrogen by Spencer Percy APPROVED BY: M. -
The Fine Structure Constant
GENERAL ⎜ ARTICLE The Fine Structure Constant Biman Nath The article discusses the importance of the fine structure constant in quantum mechanics, along with the brief history of how it emerged. Al- though Sommerfelds idea of elliptical orbits has been replaced by wave mechanics, the fine struc- ture constant he introduced has remained as an Biman Nath is an important parameter in the field of atomic struc- astrophysicist at the ture. Raman Research Institute, Bengaluru. The values of the constants of Nature, such as Newton’s gravitational constant ‘G’, determine the nature of our Universe. Among these constants, there are a few which are pure numbers and have no units. For example, there is the ‘fine structure constant’, denoted by α, which has a value roughly 1/137. The value of α is related to the electromagnetic force between subatomic charged parti- cles, and essentially determines how an atom holds to- gether its electrons. It is however not obvious why this constant has this par- ticular value. Why 1/137 and not some other value? One might think the question is meaningless, but it is not. If the value of this constant had been slightly smaller or larger, even by as little as 4%, then stars would not have been able to sustain the nuclear reac- tions in their core that produce carbon. As a result, there would not have been any carbon-based lifeforms in our Universe. Therefore, the question why α ≈ 1/137 is not completely irrelevant. Scientists have even wondered if its value remains a con- stant over time. -
Hyperfine Structure Constants on the Relativistic Coupled Cluster Level With
Hyperfine structure constants on the relativistic coupled cluster level with associated uncertainties Pi A. B. Haase,∗,y Ephraim Eliav,z Miroslav Iliaˇs,{ and Anastasia Borschevskyy yVan Swinderen Institute, University of Groningen, 9747 Groningen, The Netherlands zSchool of Chemistry, Tel Aviv University, 69978 Tel Aviv, Israel {Department of Chemistry, Faculty of Natural Sciences, Matej Bel University,Tajovsk`eho 40 , SK-97400 Banska Bystrica, Slovakia E-mail: [email protected] arXiv:2002.00887v1 [physics.atom-ph] 3 Feb 2020 1 Abstract Accurate predictions of hyperfine structure (HFS) constants are important in many areas of chemistry and physics, from the determination of nuclear electric and magnetic moments to benchmarking of new theoretical methods. We present a detailed investigation of the performance of the relativistic coupled cluster method for calculating HFS constants withing the finite-field scheme. The two selected test systems are 133Cs and 137BaF. Special attention has been paid to construct a theoretical uncertainty estimate based on investigations on basis set, electron correlation and relativistic effects. The largest contribution to the uncertainty estimate comes from higher order correlation contributions. Our conservative uncertainty estimate for the calculated HFS constants is ∼ 5.5%, while the actual deviation of our results from experimental values was < 1% in all cases. Introduction The hyperfine structure (HFS) constants parametrize the interaction between the electronic and the nuclear electromagnetic moments. The HFS consequently provides important infor- mation about the nuclear as well as the electronic structure of atoms and molecules and can serve as a fingerprint of, for example, transition metal complexes, probed by electron para- magnetic resonance (EPR) spectroscopy,1 or of atoms, ions, and small molecules in the field of atomic and molecular physics, investigated by optical or microwave spectroscopy. -
Can the Laws of Physics Be Unified? 1St Edition Pdf, Epub, Ebook
CAN THE LAWS OF PHYSICS BE UNIFIED? 1ST EDITION PDF, EPUB, EBOOK Paul Langacker | 9781400885503 | | | | | Can the Laws of Physics Be Unified? 1st edition PDF Book To test this, you open the hood of the car and examine the oil level. And, whereas a law is a postulate that forms the foundation of the scientific method, a theory is the end result of that process. These analytical skills will help you to excel academically, and they will also help you to think critically in any professional career you choose to pursue. Hawking 28 February Over the centuries, the curiosity of the human race has led us collectively to explore and catalog a tremendous wealth of information. Order a print copy. Such laws are intrinsic to the universe; humans did not create them and so cannot change them. Physical laws in classical mechanics. Newton's laws of motion". You need not be a scientist to use physics. Similarly, the operation of a car's ignition system as well as the transmission of electrical signals through our body's nervous system are much easier to understand when you think about them in terms of basic physics. Physicists use models for a variety of purposes. Answer Key. Leonardo da Vinci , who studied flight and designed many speculative flying machines , understood that "An object offers as much resistance to the air as the air does to the object". Galileo Galilei , however, realised that a force is necessary to change the velocity of a body, i. He goes on to explain field theory, internal symmetries, Yang-Mills theories, strong and electroweak interactions, the Higgs boson discovery, and neutrino physics. -
Investigation on Radiative Corrections Related to the Fine Structure and Hyperfine Structure
UNIVERSITY OF NAIROBI INVESTIGATION ON RADIATIVE CORRECTIONS RELATED TO THE FINE STRUCTURE AND HYPERFINE STRUCTURE By OBEGI, ISAAC SANI I56/68841/2013 A research project submitted in partial fulfillment for the requirements for the award of a Master of Science degree in Physics of the University of Nairobi. APRIL, 2015 i DECLARATION AND CERTIFICATION This research project is my own work and has never been submitted for examination in any other University or Research Institution for work leading to award of a degree Mr. Obegi Sani Isaac Department of Physics, University of Nairobi Signed……………………………………….. Dated………………………………………… This work has been submitted with our authority as University supervisors DR. SILAS MURERAMANZI Department of Physics, University of Nairobi Signed…………………….. Dated……………………… DR. N. M. MONYONKO DR. GEORGE MAUMBA Department of Physics, Department of Physics, University of Nairobi University of Nairobi Signed…………………….. Signed…………………… Dated……………………… Dated……………………… ii Abstract Radiative corrections related to the fine structure, Lamb shift and hyperfine structure of atomic energy levels are studied. Since the perturbation Hamiltonian is very small compared to zero order Hamiltonian first order perturbation is used theory to find the respective corrections. The expressions obtained for the fine structure of hydrogen atom using the relativistic approach coincides with those obtained using the Dirac equation and the fine structure correction is 2 표 proportional to 훼 퐸푛 , which is a small fraction of the Bohr energy. The Lamb shift correction is 3 표 -3 2 표 proportional to 훼 퐸푛 . While the hyperfine structure correction is proportional to 10 훼 퐸푛 . The implications of fine structure and hyperfine structure are seen as an outcome of very small corrections. -
2.5. the Fine Structure of a Hydrogen Atom
Phys460.nb 33 0 0 0= ψ a A H'-H'A ψb = (2.281) 0 0 0 0 0 0 0 0 0 0 ψa A H' ψb - ψ a H'A ψb =A a ψa H' ψb -A b ψa H' ψb =(A a -A b) ψa H' ψb 0 0 If Aa ≠A b, this equation means that ψa H' ψb = 0. 0 0 For this situation, although we have a degeneracy, one can just do non-degenerate perturbation for ψa and ψb (separately) and there will be no singularities at all. 2.5. the fine structure of a hydrogen atom 2.5.1. Relativistic correction In QMI, we solved an ideal model for a hydrogen atom (i.e. a particle in 1/r potential). In a real hydrogen atom, that model missed some of the physics, and one of them is relativistic effects. Q: what is the energy of a particle, if the particle is moving at speed v and the rest mass m. m E=Mc 2 = c2 2 (2.282) 1- v c2 Q: what is the momentum of a particle, if the particle is moving at speed v and the rest mass m. m p =Mv= v 2 (2.283) 1- v c2 As a result, E= p2 c2 +m 2 c4 (2.284) To prove this relation, we start from the r.h.s., p2 c2 +m 2 c4 = v2 2 2 2 2 2 m2 c41- 2 2 2 2 4 2 2 2 2 4 m v m v c c2 m v c +m c -m c v m c m (2.285) c2 +m 2 c4 = + = = = c2 =E v2 v2 v2 v2 v2 1- 2 1- 2 1- 2 1- 2 1- 2 2 c c c c c 1- v c2 This relation between E and p is an very important relation for relativistic physics! Q: what is kinetic energy? A: First, find the energy of a particle when it is not moving p = 0. -
Fine and Hyperfine Structure of the Hydrogen Atom
UNIT 4 Fine and hyperfine structure of the hydrogen atom Notes by N. Sirica and R. Van Wesep Previously, we solved the time-independent Sch¨odingerequation for the Hydro- gen atom, described by the Hamiltonian p2 e2 H = − (1) 2m r Where e is the electron’s charge in your favorite units. However, this is not really the Hamiltonian for the Hydrogen atom. It is non-relativistic and it does not contain spin. In order to completely describe the Hydrogen we would need to use the Dirac equation. We will not introduce that equation here, but we will say a few words about the most important energy level of the relativistic Hydrogen atom, namely the rest mass energy. E = mc2 ≈ 0.5MeV (2) We can compare this to the ground state (ionization) energy we found for the Hamiltonian in 1. 2 E = −Eion ≈ 13.6eV ¿ mc (3) Even though the rest mass energy is so much larger, it appears constant in the non-relativistic regime. Since differences in energy are important, we could ignore it before. The rest mass energy may be large, but it does not enter the world of everyday experience. Regardless, it is fruitful to investigate the relative size of the ionization energy to the rest mass energy. E me4 1 e4 α2 ion = = = (4) mc2 2~2 mc2 2c2~2 2 86 UNIT 4: Fine and hyperfine structure of the hydrogen atom e2 1 Where α = ~c = 137 is a fundamental constant of nature. No one understands it, but it is important that it is small. -
Exciton Fine-Structure Splitting in Self-Assembled Lateral Inas/Gaas
Exciton Fine-Structure Splitting in Self- Assembled Lateral InAs/GaAs Quantum-Dot Molecular Structures Stanislav Filippov, Yuttapoom Puttisong, Yuqing Huang, Irina A Buyanova, Suwaree Suraprapapich, Charles. W. Tu and Weimin Chen Linköping University Post Print N.B.: When citing this work, cite the original article. Original Publication: Stanislav Filippov, Yuttapoom Puttisong, Yuqing Huang, Irina A Buyanova, Suwaree Suraprapapich, Charles. W. Tu and Weimin Chen, Exciton Fine-Structure Splitting in Self- Assembled Lateral InAs/GaAs Quantum-Dot Molecular Structures, 2015, ACS Nano, (9), 6, 5741-5749. http://dx.doi.org/10.1021/acsnano.5b01387 Copyright: American Chemical Society http://pubs.acs.org/ Postprint available at: Linköping University Electronic Press http://urn.kb.se/resolve?urn=urn:nbn:se:liu:diva-118007 1 Exciton Fine-Structure Splitting in Self-Assembled Lateral InAs/GaAs Quantum-Dot Molecular Structures Stanislav Fillipov,1,† Yuttapoom Puttisong,1, † Yuqing Huang,1 Irina A. Buyanova,1 Suwaree Suraprapapich,2 Charles W. Tu2 and Weimin M. Chen1,* 1Department of Physics, Chemistry and Biology, Linköping University, S-581 83 Linköping, Sweden 2Department of Electrical and Computer Engineering, University of California, La Jolla, CA 92093, USA ABSTRACT Fine-structure splitting (FSS) of excitons in semiconductor nanostructures is a key parameter that has significant implications in photon entanglement and polarization conversion between electron spins and photons, relevant to quantum information technology and spintronics. Here, we investigate exciton FSS in self-organized lateral InAs/GaAs quantum-dot molecular structures (QMSs) including laterally-aligned double quantum dots (DQDs), quantum-dot clusters (QCs) and quantum rings (QRs), by employing polarization-resolved micro-photoluminescence (µPL) spectroscopy.