Systems Engineering to Systems Politics
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How USAF's Missile Program Helped the Nation Off the Pad
Iii ANNIVERSARY There was no lack of rocketry art when Sputnik jolted the US and the free world. The Army, Navy, and Air Force had all been working with missiles for some years, and many rocket spe- cialists had foreseen the future significance of space. But the national capabilities were splintered. As NASA came into being, with a strong need for large-scale program know-how, it was the Air Force, fresh from its missile management experience, that could offer the most useful aid in getting the space program under way . How USAF's Missile Program Helped the Nation off the Pad BY WILLIAM LEA VITT ASSOCIATE EDITOR, AIR FORCE/SPACE DIGEST "From this effort has emerged not only the major portion of our national missile force but also the prime base of technology and management skill underpinning the total national space effort. Many of our space accomplishments to date—both military and civilian—simply could not have been undertaken successfully with- out the prior experience gained in the Air Force missile development program." —SECRETARY OF THE AIR FORCE EUGENE M. ZUCKERT T IS a fact, documented in the public prints, Just one aspect of this sizable Air Force role has in congressional reports, and above all, on been the large number of Air Force officers who have launch pads and tracking sites around the served the National Aeronautics and Space Adminis- world, that the US Air Force has made mas- tration on direct loan or in supportive Air Force efforts, sive contributions of men, hardware, and since the civilian space agency's establishment in 1958. -
Effective Quantum Field Theories Thomas Mannel Theoretical Physics I (Particle Physics) University of Siegen, Siegen, Germany
Generating Functionals Functional Integration Renormalization Introduction to Effective Quantum Field Theories Thomas Mannel Theoretical Physics I (Particle Physics) University of Siegen, Siegen, Germany 2nd Autumn School on High Energy Physics and Quantum Field Theory Yerevan, Armenia, 6-10 October, 2014 T. Mannel, Siegen University Effective Quantum Field Theories: Lecture 1 Generating Functionals Functional Integration Renormalization Overview Lecture 1: Basics of Quantum Field Theory Generating Functionals Functional Integration Perturbation Theory Renormalization Lecture 2: Effective Field Thoeries Effective Actions Effective Lagrangians Identifying relevant degrees of freedom Renormalization and Renormalization Group T. Mannel, Siegen University Effective Quantum Field Theories: Lecture 1 Generating Functionals Functional Integration Renormalization Lecture 3: Examples @ work From Standard Model to Fermi Theory From QCD to Heavy Quark Effective Theory From QCD to Chiral Perturbation Theory From New Physics to the Standard Model Lecture 4: Limitations: When Effective Field Theories become ineffective Dispersion theory and effective field theory Bound Systems of Quarks and anomalous thresholds When quarks are needed in QCD É. T. Mannel, Siegen University Effective Quantum Field Theories: Lecture 1 Generating Functionals Functional Integration Renormalization Lecture 1: Basics of Quantum Field Theory Thomas Mannel Theoretische Physik I, Universität Siegen f q f et Yerevan, October 2014 T. Mannel, Siegen University Effective Quantum -
Chapter 6.Qxd
CHAPTER 6: The NASA Family The melding of all of the NASA centers, contractors, universities, and often strong personalities associated with each of them into the productive and efficient organization necessary to complete NASA’s space missions became both more critical and more difficult as NASA turned its attention from Gemini to Apollo. The approach and style and, indeed, the personality of each NASA center differed sharply. The Manned Spacecraft Center was distinctive among all the rest. Fortune magazine suggested in 1967 that the scale of NASA’s operation required a whole new approach and style of management: “To master such massively complex and expensive problems, the agency has mobilized some 20,000 individual firms, more than 400,000 workers, and 200 colleges and universities in a combine of the most advanced resources of American civilization.” The author referred to some of the eight NASA centers and assorted field installations as “pockets of sovereignty” which exercised an enormous degree of independence and autonomy.1 An enduring part of the management problem throughout the Mercury and Gemini programs that became compounded under Apollo, because of its greater technical challenges, was the diversity and distinctiveness of each of the NASA centers. The diverse cultures and capabilities represented by each of the centers were at once the space program’s greatest resource and its Achilles’ heel. NASA was a hybrid organization. At its heart was Langley Memorial Aeronautical Laboratory established by Congress in 1917 near Hampton, Virginia, and formally dedicated in 1920. It became the Langley Research Center. Langley created the Ames Aeronautical Laboratory at Moffett Field, California, in 1939. -
Large-Deviation Principles, Stochastic Effective Actions, Path Entropies
Large-deviation principles, stochastic effective actions, path entropies, and the structure and meaning of thermodynamic descriptions Eric Smith Santa Fe Institute, 1399 Hyde Park Road, Santa Fe, NM 87501, USA (Dated: February 18, 2011) The meaning of thermodynamic descriptions is found in large-deviations scaling [1, 2] of the prob- abilities for fluctuations of averaged quantities. The central function expressing large-deviations scaling is the entropy, which is the basis for both fluctuation theorems and for characterizing the thermodynamic interactions of systems. Freidlin-Wentzell theory [3] provides a quite general for- mulation of large-deviations scaling for non-equilibrium stochastic processes, through a remarkable representation in terms of a Hamiltonian dynamical system. A number of related methods now exist to construct the Freidlin-Wentzell Hamiltonian for many kinds of stochastic processes; one method due to Doi [4, 5] and Peliti [6, 7], appropriate to integer counting statistics, is widely used in reaction-diffusion theory. Using these tools together with a path-entropy method due to Jaynes [8], this review shows how to construct entropy functions that both express large-deviations scaling of fluctuations, and describe system-environment interactions, for discrete stochastic processes either at or away from equilibrium. A collection of variational methods familiar within quantum field theory, but less commonly applied to the Doi-Peliti construction, is used to define a “stochastic effective action”, which is the large-deviations rate function for arbitrary non-equilibrium paths. We show how common principles of entropy maximization, applied to different ensembles of states or of histories, lead to different entropy functions and different sets of thermodynamic state variables. -
THE BI-WEEKLY NEWS LETTER College Placement Association, Inc
SPEAKING OF PEOPLE Dr. F. Thomas Sheeder, director. Student Financial and Career Plan ning, has been named to the Organ ization Committee of the Southern THE BI-WEEKLY NEWS LETTER College Placement Association, Inc. He is past chairman of the SCPA Professional Development Committee... Dr. Marshall R. Jones, chair man, psychology, and member of the American Psychological As sociation's Council of Represent Volume 10, No. 3 October 20, 1969 atives, attended the Public Policy Conference for Psychologists at MOON SAMPLES University of Miami scientists are currently Williamsburg, Va. October 5-10... STUDIED HERE studying 51.8 grams of lunar material brought An article, "Voltaire and Hum back to earth by the Apollo 11 crew in July. Dr. phry Clinker," by Dr. Evelyn Sidney W. Fox, director of the Institute of Molecular Evolution and Helmick, English, was published bioscience consultant to the National Aeronautics and Space Adminis in Vol. 68, 1969 issue of Studies tration since 1960, is working with co-investigators Dr. Kaoru Harada on Voltaire and the 18th Century, and Dr. George Mueller. Dr. Fox told a special press conference Oct. Voltaire Institute, Geneva, Switz 6 that in simple layman's terms the object of their experiments is to erland... determine if there is evidence of molecular evolution on the moon. Dr. Grover A. J. Noetzel, econ The UM will receive chips of moon rock at a later date, he said. omics, spoke on "Economic Foun dations of Real Estate" to the Mi ami Board of Realtors Oct. 15, on UM SPONSORS TWO The University of Miami sponsored two "Economic Opportunities in the COMMUNITY MEETINGS major meetings of community interest Seventies," to the National As recently. -
Comparison Between Quantum and Classical Dynamics in the Effective Action Formalism
Proceedings of the International School of Physics "Enrico Fermi" Course CXLIII. G. Casati, I. Guarneri and U. Smilansky (Eds.) lOS Press, Amsterdam 2000 Comparison between quantum and classical dynamics in the effective action formalism F. CAMETTI Dipartimento di Fisica, Universitd della Calabria - 87036 Arcavacata di Rende, Italy and Istituto Nazionale per la Fisica della Materia, unita di Cosenza - Italy G. JONA-LASINIO Dipartimento di Fisica, Universita di Roma "La Sapienza"- P.le A. Moro 2, 00185 Roma, Italy C. PRESILLA Dipartimento di Fisica, Universita di Roma "La Sapienza"- P.le A. Moro 2, 00185 Roma, Italy and Istituto Nazionale per la Fisica della Materia, unita di Roma "La Sapienza" - Italy F. TONINELLI Dipartimento di Fisica, Universita di Roma "La Sapienza"- P.le A. Moro 2, 00185 Roma, Italy A major difficulty in comparing quantum and classical behavior resides in the struc tural differences between the corresponding mathematical languages. The Heisenberg equations of motion are operator equations only formally identical to the classical equa tions of motion. By taking the expectation of these equations, the well-known Ehrenfest theorem provides identities which, however, are not a closed system of equations which allows to evaluate the time evolution of the system. The formalism of the effective action seems to offer a possibility of comparing quantum and classical evolutions in a system atic and logically consistent way by naturally providing approximation schemes for the expectations of the coordinates which at the zeroth order coincide with the classical evolution [1]. The effective action formalism leads to equations of motion which differ from the classical equations by the addition of terms nonlocal in the time variable. -
Introduction to Effective Field Theory
Effective Field Theories 1 Introduction to Effective Field Theory C.P. Burgess Department of Physics & Astronomy, McMaster University, 1280 Main Street West, Hamilton, Ontario, Canada, L8S 4M1 and Perimeter Institute, 31 Caroline Street North, Waterloo, Ontario, Canada, N2L 2Y5 Key Words Effective field theory; Low-energy approximation; Power-counting Abstract This review summarizes Effective Field Theory techniques, which are the modern theoretical tools for exploiting the existence of hierarchies of scale in a physical problem. The general theoretical framework is described, and explicitly evaluated for a simple model. Power- counting results are illustrated for a few cases of practical interest, and several applications to arXiv:hep-th/0701053v2 18 Jan 2007 Quantum Electrodynamics are described. CONTENTS Introduction ....................................... 2 A toy model .......................................... 3 General formulation ................................... 6 The 1PI and 1LPI actions .................................. 6 The Wilson action ...................................... 20 Ann. Rev. Nucl. Part. Sci. 2000 1056-8700/97/0610-00 Power counting ...................................... 28 A class of effective interactions ............................... 28 Power-counting rules ..................................... 29 The Effective-Lagrangian Logic ............................... 32 Applications ....................................... 34 Quantum Electrodynamics .................................. 34 Power-counting examples: QCD and Gravity ....................... 46 1 Introduction It is a basic fact of life that Nature comes to us in many scales. Galaxies, planets, aardvarks, molecules, atoms and nuclei are very different sizes, and are held together with very different binding energies. Happily enough, it is another fact of life that we don’t need to understand what is going on at all scales at once in order to figure out how Nature works at a particular scale. Like good musicians, good physicists know which scales are relevant for which compositions. -
Out of Time Ordered Effective Dynamics of a Quartic Oscillator
SciPost Phys. 7, 013 (2019) Out of time ordered effective dynamics of a quartic oscillator Bidisha Chakrabarty? and Soumyadeep Chaudhuri† International Centre for Theoretical Sciences (ICTS-TIFR), Tata Institute of Fundamental Research, Shivakote, Hesaraghatta, Bangalore 560089, India ? [email protected],† [email protected] Abstract We study the dynamics of a quantum Brownian particle weakly coupled to a thermal bath. Working in the Schwinger-Keldysh formalism, we develop an effective action of the particle up to quartic terms. We demonstrate that this quartic effective theory is dual to a stochastic dynamics governed by a non-linear Langevin equation. The Schwinger- Keldysh effective theory, or the equivalent non-linear Langevin dynamics, is insufficient to determine the out of time order correlators (OTOCs) of the particle. To overcome this limitation, we construct an extended effective action in a generalised Schwinger-Keldysh framework. We determine the additional quartic couplings in this OTO effective action and show their dependence on the bath’s 4-point OTOCs. We analyse the constraints imposed on the OTO effective theory by microscopic reversibility and thermality of the bath. We show that these constraints lead to a generalised fluctuation-dissipation rela- tion between the non-Gaussianity in the distribution of the thermal noise experienced by the particle and the thermal jitter in its damping coefficient. The quartic effective theory developed in this work provides extension of several results previously obtained for the cubic OTO dynamics of a Brownian particle. Copyright B. Chakrabarty and S. Chaudhuri. Received 14-06-2019 This work is licensed under the Creative Commons Accepted 17-07-2019 Check for Attribution 4.0 International License. -
Advanced Quantum Field Theory
Advanced Quantum Field Theory Doctoral School in Physics, EPFL Prof. Claudio Scrucca Contents 1 Basic formalism for interacting theories 4 1.1 Perturbativeapproach . 4 1.2 Correlationfunctions. ... 5 1.3 Diagrammatics .................................. 6 1.4 AsymptoticstatesandS-matrix. .... 6 1.5 Renormalization ................................. 9 1.6 Vacuum amplitude and generating functional . ....... 11 1.7 Vacuum energy and connected generating functional . ......... 12 1.8 Effective action and 1PI generating functional . ........ 13 1.9 Path-integral representation . ...... 14 2 Path integral and quantum effective action 16 2.1 Saddle-point evaluation of the effective action . ......... 16 2.2 Effective vertices and effective potential . ...... 19 2.3 Symmetry breaking and Goldstone theorem . ..... 19 2.4 Leading quantum corrections and determinants . ........ 21 2.5 World-lineformalism. 23 3 Renormalization group and running couplings 28 3.1 Renormalization at an arbitrary scale . ...... 28 3.2 Dimensionlesscouplings . 29 3.3 Computation of the renormalization group functions . .......... 31 3.4 Runningcouplings ................................ 33 3.5 Schemedependence................................ 36 3.6 Effectofmassparameters . .. .. .. .. .. .. .. 37 3.7 Minimalsubtractionschemes . 38 3.8 Resummation of leading logarithms . ..... 39 3.9 Effectiveaction .................................. 42 1 4 Symmetry breaking and quantum corrections 43 4.1 The O(N)sigmamodel ............................. 43 4.2 Diagrammatic computation of β, γ and γm .................. 44 4.3 Effectivepotential ................................ 45 4.4 Renormalization and counter-terms . ...... 46 4.5 Renormalization group analysis . ..... 47 4.6 Radiativesymmetrybreaking . 48 5 Yang-Mills gauge theories 51 5.1 Gauge-fixing, ghosts and Feynman rules . ..... 51 5.2 BRSTsymmetry ................................. 56 5.3 Diagrammatic computation of β. ........................ 58 5.4 Effectiveaction .................................. 61 6 Effective theories 67 6.1 Low-energy effective theories . -
Density Functional Theory from Effective Actions
Density Functional Theory from Effective Actions Dick Furnstahl Department of Physics Ohio State University September, 2005 Collaborators: A. Bhattacharyya, S. Bogner, H.-W. Hammer, S. Puglia, S. Ramanan, A. Schwenk, B. Serot Outline Overview Action Topics Summary Outline Overview: Microscopic DFT Effective Actions and DFT Issues and Ideas and Open Problems Summary Dick Furnstahl DFT from Effective Actions Outline Overview Action Topics Summary Intro Vlowk Philosophy ChPT NM Plan Outline Overview: Microscopic DFT Effective Actions and DFT Issues and Ideas and Open Problems Summary Dick Furnstahl DFT from Effective Actions Outline Overview Action Topics Summary Intro Vlowk Philosophy ChPT NM Plan DFT from Microscopic NN··· N Interactions What? Constructive density functional theory (DFT) for nuclei Why now? Progress in chiral EFT Application of RG (e.g., low-momentum interactions) Advances in computational tools and methods How? Use framework of effective actions with EFT principles EFT interactions and operators evolved to low-momentum Few-body input not enough (?) =⇒ input from many-body Merge with other energy functional developments Dick Furnstahl DFT from Effective Actions Outline Overview Action Topics Summary Intro Vlowk Philosophy ChPT NM Plan Density Functional Theory (DFT) with Coulomb Dominant application: inhomogeneous Atomization Energies of Hydrocarbon Molecules electron gas 20 Interacting point electrons 0 in static potential of -20 atomic nuclei -40 “Ab initio” calculations of -60 Hartree-Fock DFT Local Spin Density Approximation atoms, molecules, crystals, DFT Generalized Gradient Approximation surfaces, . % deviation from experiment -80 -100 H C C H CH C H C H C H HF is good starting point, 2 2 2 2 4 2 4 2 6 6 6 molecule DFT/LSD is better, DFT/GGA is better still, . -
Lecture 11 the Effective Action
Lecture 11 The Effective Action So far, in our treatment of the spontaneous breaking of a continuous symmetry, when we considered the the minimization of the potential of the field in question to obtain its ground state expectation value, we were working at the classical level. Quantum corrections will renormalize the parameters of the theory, including those of the potential. In fact, they can also add new field dependent terms and potentially change the position of the minimum of the potential. In order to include quantum corrections we will define a function in the full quantum theory such that its minimum is actually h0jφ(x)j0i ; (11.1) where we define j0i as the state with no quanta of the field φ(x). To leading order, this function should coincide with the classical potential. We start with the generating functional in the presence of a linearly coupled source J(x) given by Z R 4 Z[J] = eiW [J] = Dφ eiS[φ]+i d xJ(x)φ(x) : (11.2) We can then write R 4 δW δ ln Z R Dφ φ(x) eiS[φ]+i d xJ(x)φ(x) = −i = ; (11.3) δJ(x) δJ(x) R Dφ eiS[φ]+i R d4xJ(x)φ(x) which means that δW = h0jφ(x)j0i ≡ φ (x) ; (11.4) δJ(x) c 1 2 LECTURE 11. THE EFFECTIVE ACTION gives the expectation value of the operator φ(x). We now define the effective action as a functional of φc(x) as Z 4 Γ[φc(x)] ≡ W [J] − d xJ(x)φc(x) : (11.5) From the definition above, we see that Γ[φc(x)] is the Legendre transform of W [J], with J(x) and φc(x) conjugate Legendre variables. -
2008 Annual Report
AMERIC A N P H Y S I C A L S OCIETY 2 0 0 8 A N N U A L R E P O R T APS APS The AMERICAN PHYSICAL SOCIETY strives to: Be the leading voice for physics and an authoritative source of physics information for the advancement of physics and the benefit of humanity; Collaborate with national scientific societies for the advancement of science, science education, and the science community; Cooperate with international physics societies to promote physics, to support physicists worldwide, and to foster international collaboration; Have an active, engaged, and diverse membership, and support the activities of its units and members. F R O M T H E PRESIDEN T his past year saw continued growth and APS Gender Equity Conference, in which I played an ac- achievement for APS. Membership in the tive role in 2007. Society grew by close to 1000, exceeding APS staff continued to work to enhance programs 47,000. New student members continue serving the physics community. These include efforts to to dominate the growth, and students be- take physics to the public through the popular Physics came more active in APS governance, Quest program for middle school students. Over 11,000 Twith the first student member of the APS Council tak- kits were distributed to teachers across the country to ing her seat in 2008. Submissions to APS journals contin- provide the materials needed for over 200,000 students ued to increase, and APS added a new online publication, to participate in the 2008 quest. A major emphasis was Physics, while celebrating the 50th anniversary of Physical the ongoing lobbying efforts to increase funding for the Review Letters.