Gravitational Redshift in Quantum-Clock Interferometry
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An Analysis of Gravitational Redshift from Rotating Body
An analysis of gravitational redshift from rotating body Anuj Kumar Dubey∗ and A K Sen† Department of Physics, Assam University, Silchar-788011, Assam, India. (Dated: July 29, 2021) Gravitational redshift is generally calculated without considering the rotation of a body. Neglect- ing the rotation, the geometry of space time can be described by using the spherically symmetric Schwarzschild geometry. Rotation has great effect on general relativity, which gives new challenges on gravitational redshift. When rotation is taken into consideration spherical symmetry is lost and off diagonal terms appear in the metric. The geometry of space time can be then described by using the solutions of Kerr family. In the present paper we discuss the gravitational redshift for rotating body by using Kerr metric. The numerical calculations has been done under Newtonian approximation of angular momentum. It has been found that the value of gravitational redshift is influenced by the direction of spin of central body and also on the position (latitude) on the central body at which the photon is emitted. The variation of gravitational redshift from equatorial to non - equatorial region has been calculated and its implications are discussed in detail. I. INTRODUCTION from principle of equivalence. Snider in 1972 has mea- sured the redshift of the solar potassium absorption line General relativity is not only relativistic theory of grav- at 7699 A˚ by using an atomic - beam resonance - scat- itation proposed by Einstein, but it is the simplest theory tering technique [5]. Krisher et al. in 1993 had measured that is consistent with experimental data. Predictions of the gravitational redshift of Sun [6]. -
Information and Entropy in Quantum Theory
Information and Entropy in Quantum Theory O J E Maroney Ph.D. Thesis Birkbeck College University of London Malet Street London WC1E 7HX arXiv:quant-ph/0411172v1 23 Nov 2004 Abstract Recent developments in quantum computing have revived interest in the notion of information as a foundational principle in physics. It has been suggested that information provides a means of interpreting quantum theory and a means of understanding the role of entropy in thermodynam- ics. The thesis presents a critical examination of these ideas, and contrasts the use of Shannon information with the concept of ’active information’ introduced by Bohm and Hiley. We look at certain thought experiments based upon the ’delayed choice’ and ’quantum eraser’ interference experiments, which present a complementarity between information gathered from a quantum measurement and interference effects. It has been argued that these experiments show the Bohm interpretation of quantum theory is untenable. We demonstrate that these experiments depend critically upon the assumption that a quantum optics device can operate as a measuring device, and show that, in the context of these experiments, it cannot be consistently understood in this way. By contrast, we then show how the notion of ’active information’ in the Bohm interpretation provides a coherent explanation of the phenomena shown in these experiments. We then examine the relationship between information and entropy. The thought experiment connecting these two quantities is the Szilard Engine version of Maxwell’s Demon, and it has been suggested that quantum measurement plays a key role in this. We provide the first complete description of the operation of the Szilard Engine as a quantum system. -
Gravitational Redshift/Blueshift of Light Emitted by Geodesic
Eur. Phys. J. C (2021) 81:147 https://doi.org/10.1140/epjc/s10052-021-08911-5 Regular Article - Theoretical Physics Gravitational redshift/blueshift of light emitted by geodesic test particles, frame-dragging and pericentre-shift effects, in the Kerr–Newman–de Sitter and Kerr–Newman black hole geometries G. V. Kraniotisa Section of Theoretical Physics, Physics Department, University of Ioannina, 451 10 Ioannina, Greece Received: 22 January 2020 / Accepted: 22 January 2021 / Published online: 11 February 2021 © The Author(s) 2021 Abstract We investigate the redshift and blueshift of light 1 Introduction emitted by timelike geodesic particles in orbits around a Kerr–Newman–(anti) de Sitter (KN(a)dS) black hole. Specif- General relativity (GR) [1] has triumphed all experimental ically we compute the redshift and blueshift of photons that tests so far which cover a wide range of field strengths and are emitted by geodesic massive particles and travel along physical scales that include: those in large scale cosmology null geodesics towards a distant observer-located at a finite [2–4], the prediction of solar system effects like the perihe- distance from the KN(a)dS black hole. For this purpose lion precession of Mercury with a very high precision [1,5], we use the killing-vector formalism and the associated first the recent discovery of gravitational waves in Nature [6–10], integrals-constants of motion. We consider in detail stable as well as the observation of the shadow of the M87 black timelike equatorial circular orbits of stars and express their hole [11], see also [12]. corresponding redshift/blueshift in terms of the metric physi- The orbits of short period stars in the central arcsecond cal black hole parameters (angular momentum per unit mass, (S-stars) of the Milky Way Galaxy provide the best current mass, electric charge and the cosmological constant) and the evidence for the existence of supermassive black holes, in orbital radii of both the emitter star and the distant observer. -
A Hypothesis About the Predominantly Gravitational Nature of Redshift in the Electromagnetic Spectra of Space Objects Stepan G
A Hypothesis about the Predominantly Gravitational Nature of Redshift in the Electromagnetic Spectra of Space Objects Stepan G. Tiguntsev Irkutsk National Research Technical University 83 Lermontov St., Irkutsk, 664074, Russia [email protected] Abstract. The study theoretically substantiates the relationship between the redshift in the electromagnetic spectrum of space objects and their gravity and demonstrates it with computational experiments. Redshift, in this case, is a consequence of a decrease in the speed of the photons emitted from the surface of objects, which is caused by the gravity of these objects. The decline in the speed of photons due to the gravity of space gravitating object (GO) is defined as ΔC = C-C ', where: C' is the photon speed changed by the time the receiver records it. Then, at a change in the photon speed between a stationary source and a receiver, the redshift factor is determined as Z = (C-C ')/C'. Computational experiments determined the gravitational redshift of the Earth, the Sun, a neutron star, and a quasar. Graph of the relationship between the redshift and the ratio of sizes to the mass of any space GOs was obtained. The findings indicate that the distance to space objects does not depend on the redshift of these objects. Keywords: redshift, computational experiment, space gravitating object, photon, radiation source, and receiver. 1. Introduction In the electromagnetic spectrum of space objects, redshift is assigned a significant role in creating a physical picture of the Universe. Redshift is observed in almost all space objects (stars, galaxies, quasars, and others). As a consequence of the Doppler effect, redshift indicates the movement of almost all space objects from an observer on the Earth [1]. -
Notes on the Theory of Quantum Clock
NOTES ON THE THEORY OF QUANTUM CLOCK I.Tralle1, J.-P. Pellonp¨a¨a2 1Institute of Physics, University of Rzesz´ow,Rzesz´ow,Poland e-mail:[email protected] 2Department of Physics, University of Turku, Turku, Finland e-mail:juhpello@utu.fi (Received 11 March 2005; accepted 21 April 2005) Abstract In this paper we argue that the notion of time, whatever complicated and difficult to define as the philosophical cat- egory, from physicist’s point of view is nothing else but the sum of ’lapses of time’ measured by a proper clock. As far as Quantum Mechanics is concerned, we distinguish a special class of clocks, the ’atomic clocks’. It is because at atomic and subatomic level there is no other possibility to construct a ’unit of time’ or ’instant of time’ as to use the quantum transitions between chosen quantum states of a quantum ob- ject such as atoms, atomic nuclei and so on, to imitate the periodic circular motion of a clock hand over the dial. The clock synchronization problem is also discussed in the paper. We study the problem of defining a time difference observable for two-mode oscillator system. We assume that the time dif- ference obsevable is the difference of two single-mode covariant Concepts of Physics, Vol. II (2005) 113 time observables which are represented as a time shift covari- ant normalized positive operator measures. The difficulty of finding the correct value space and normalization for time dif- ference is discussed. 114 Concepts of Physics, Vol. II (2005) Notes on the Theory of Quantum Clock And the heaven departed as a scroll when it is rolled together;.. -
Engineering Ultrafast Quantum Frequency Conversion
Engineering ultrafast quantum frequency conversion Der Naturwissenschaftlichen Fakultät der Universität Paderborn zur Erlangung des Doktorgrades Dr. rer. nat. vorgelegt von BENJAMIN BRECHT aus Nürnberg To Olga for Love and Support Contents 1 Summary1 2 Zusammenfassung3 3 A brief history of ultrafast quantum optics5 3.1 1900 – 1950 ................................... 5 3.2 1950 – 2000 ................................... 6 3.3 2000 – today .................................. 8 4 Fundamental theory 11 4.1 Waveguides .................................. 11 4.1.1 Waveguide modelling ........................ 12 4.1.2 Spatial mode considerations .................... 14 4.2 Light-matter interaction ........................... 16 4.2.1 Nonlinear polarisation ........................ 16 4.2.2 Three-wave mixing .......................... 17 4.2.3 More on phasematching ...................... 18 4.3 Ultrafast pulses ................................. 21 4.3.1 Time-bandwidth product ...................... 22 4.3.2 Chronocyclic Wigner function ................... 22 4.3.3 Pulse shaping ............................. 25 5 From classical to quantum optics 27 5.1 Speaking quantum .............................. 27 iii 5.1.1 Field quantisation in waveguides ................. 28 5.1.2 Quantum three-wave mixing .................... 30 5.1.3 Time-frequency representation .................. 32 5.1.3.1 Joint spectral amplitude functions ........... 32 5.1.3.2 Schmidt decomposition ................. 35 5.2 Understanding quantum ........................... 36 5.2.1 Parametric -
Unified Approach to Redshift in Cosmological/Black Hole
Unified approach to redshift in cosmological /black hole spacetimes and synchronous frame A. V. Toporensky Sternberg Astronomical Institute, Lomonosov Moscow State University, Universitetsky Prospect, 13, Moscow 119991, Russia and Kazan Federal University, Kremlevskaya 18, Kazan 420008, Russia∗ O. B. Zaslavskii Department of Physics and Technology, Kharkov V.N. Karazin National University, 4 Svoboda Square, Kharkov 61022, Ukraine and Kazan Federal University, Kremlevskaya 18, Kazan 420008 Russia† S. B. Popov Sternberg Astronomical Institute, Lomonosov Moscow State University, Universitetsky Prospect, 13, Moscow 119991, Russia Usually, interpretation of redshift in static spacetimes (for example, near black holes) is opposed to that in cosmology. In this methodological note we show that both explanations are unified in a natural picture. This is achieved if, considering the static spacetime, one (i) makes a transition to a synchronous frame, and (ii) returns to the original frame by means of local Lorentz boost. To reach our goal, we consider arXiv:1704.08308v3 [gr-qc] 1 Mar 2018 a rather general class of spherically symmetric spacetimes. In doing so, we construct frames that generalize the well-known Lemaitre and Painlev´e–Gullstand ones and elucidate the relation between them. This helps us to understand, in an unifying approach, how gravitation reveals itself in different branches of general relativity. This framework can be useful for general relativity university courses. PACS numbers: 04.20.-q; 04.20.Cv; 04.70.Bw ∗Electronic address: [email protected] †Electronic address: [email protected] 2 I. INTRODUCTION Though the calculation of redshifts in General Relativity (GR) has no principal diffi- culties, their interpretation continues to be a source of debates. -
Cosmic Microwave Background
1 29. Cosmic Microwave Background 29. Cosmic Microwave Background Revised August 2019 by D. Scott (U. of British Columbia) and G.F. Smoot (HKUST; Paris U.; UC Berkeley; LBNL). 29.1 Introduction The energy content in electromagnetic radiation from beyond our Galaxy is dominated by the cosmic microwave background (CMB), discovered in 1965 [1]. The spectrum of the CMB is well described by a blackbody function with T = 2.7255 K. This spectral form is a main supporting pillar of the hot Big Bang model for the Universe. The lack of any observed deviations from a 7 blackbody spectrum constrains physical processes over cosmic history at redshifts z ∼< 10 (see earlier versions of this review). Currently the key CMB observable is the angular variation in temperature (or intensity) corre- lations, and to a growing extent polarization [2–4]. Since the first detection of these anisotropies by the Cosmic Background Explorer (COBE) satellite [5], there has been intense activity to map the sky at increasing levels of sensitivity and angular resolution by ground-based and balloon-borne measurements. These were joined in 2003 by the first results from NASA’s Wilkinson Microwave Anisotropy Probe (WMAP)[6], which were improved upon by analyses of data added every 2 years, culminating in the 9-year results [7]. In 2013 we had the first results [8] from the third generation CMB satellite, ESA’s Planck mission [9,10], which were enhanced by results from the 2015 Planck data release [11, 12], and then the final 2018 Planck data release [13, 14]. Additionally, CMB an- isotropies have been extended to smaller angular scales by ground-based experiments, particularly the Atacama Cosmology Telescope (ACT) [15] and the South Pole Telescope (SPT) [16]. -
Notes on the Theory of Quantum Clock
NOTES ON THE THEORY OF QUANTUM CLOCK I.Tralle1, J.-P. Pellonp¨a¨a2 1Institute of Physics, University of Rzesz´ow,Rzesz´ow,Poland e-mail:[email protected] 2Department of Physics, University of Turku, Turku, Finland e-mail:juhpello@utu.fi (Received 11 March 2005; accepted 21 April 2005) Abstract In this paper we argue that the notion of time, whatever complicated and difficult to define as the philosophical cat- egory, from physicist’s point of view is nothing else but the sum of ’lapses of time’ measured by a proper clock. As far as Quantum Mechanics is concerned, we distinguish a special class of clocks, the ’atomic clocks’. It is because at atomic and subatomic level there is no other possibility to construct a ’unit of time’ or ’instant of time’ as to use the quantum transitions between chosen quantum states of a quantum ob- ject such as atoms, atomic nuclei and so on, to imitate the periodic circular motion of a clock hand over the dial. The clock synchronization problem is also discussed in the paper. We study the problem of defining a time difference observable for two-mode oscillator system. We assume that the time dif- ference obsevable is the difference of two single-mode covariant Concepts of Physics, Vol. II (2005) 113 time observables which are represented as a time shift covari- ant normalized positive operator measures. The difficulty of finding the correct value space and normalization for time dif- ference is discussed. 114 Concepts of Physics, Vol. II (2005) Notes on the Theory of Quantum Clock And the heaven departed as a scroll when it is rolled together;.. -
The Boundaries of Nature: Special & General Relativity and Quantum
“The Boundaries of Nature: Special & General Relativity and Quantum Mechanics, A Second Course in Physics” Edwin F. Taylor's acceptance speech for the 1998 Oersted medal presented by the American Association of Physics Teachers, 6 January 1998 Edwin F. Taylor Center for Innovation in Learning, Carnegie Mellon University, Pittsburgh, PA 15213 (Now at 22 Hopkins Road, Arlington, MA 02476-8109, email [email protected] , web http://www.artsaxis.com/eftaylor/ ) ABSTRACT Public hunger for relativity and quantum mechanics is insatiable, and we should use it selectively but shamelessly to attract students, most of whom will not become physics majors, but all of whom can experience "deep physics." Science, engineering, and mathematics students, indeed anyone comfortable with calculus, can now delve deeply into special and general relativity and quantum mechanics. Big chunks of general relativity require only calculus if one starts with the metric describing spacetime around Earth or black hole. Expressions for energy and angular momentum follow, along with orbit predictions for particles and light. Feynman's Sum Over Paths quantum theory simply commands the electron: Explore all paths. Students can model this command with the computer, pointing and clicking to tell the electron which paths to explore; wave functions and bound states arise naturally. A second full year course in physics covering special relativity, general relativity, and quantum mechanics would have wide appeal -- and might also lead to significant advancements in upper-level courses for the physics major. © 1998 American Association of Physics Teachers INTRODUCTION It is easy to feel intimidated by those who have in the past received the Oersted Medal, especially those with whom I have worked closely in the enterprise of physics teaching: Edward M. -
Time and Frequency Division Report
Time and Frequency Division Goal The broad mission of the Time and Frequency Division is to provide official U.S. time and related quantities to support a wide range of uses in industry, national infrastructure, research, and among the general public. DIVISION STRATEGY The division’s research and metrology ac- tivities comprise three vertically integrated components, each of which constitutes a strategic element: 1. Official time: Accurate and precise realization of official U.S. time (UTC) and frequency. 2. Dissemination: A wide range of mea- surement services to efficiently and effectively distribute U.S. time and frequency and related quantities – pri- marily through free broadcast services available to any user 24/7/365. 3. Research: Research and technolo- gy development to improve time and frequency standards and dissemination. Part of this research includes high-impact programs in areas such as quantum information processing, atom-based sensors, and laser development and applications, which evolved directly from research to make better frequency standards (atomic clocks). Overview These three components – official time, dissemination, and research – are closely integrated. For example, all Division dissemination services tie directly to the Division’s realization of official time (UTC), and much of the Division’s research is enabled by the continual availability of precision UTC. Our modern technology and economy depend critically on the broad availability of precision timing, frequency, and synchronization. NIST realization and dissemination of time and frequency – continually improved by NIST research and development – is a crucial part of a series of informal national timing infrastructures that enable such essential technologies as: • Telecommunications and computer networks • Utility distribution • GPS, widely available in every cell phone and smartphone as well as GPS receivers • Electronic financial transactions 1 • National security and intelligence applications • Research Strategic Goal: Official Time Intended Outcome and Background U.S. -
Quantum Physics in Space
Quantum Physics in Space Alessio Belenchiaa,b,∗∗, Matteo Carlessob,c,d,∗∗, Omer¨ Bayraktare,f, Daniele Dequalg, Ivan Derkachh, Giulio Gasbarrii,j, Waldemar Herrk,l, Ying Lia Lim, Markus Rademacherm, Jasminder Sidhun, Daniel KL Oin, Stephan T. Seidelo, Rainer Kaltenbaekp,q, Christoph Marquardte,f, Hendrik Ulbrichtj, Vladyslav C. Usenkoh, Lisa W¨ornerr,s, Andr´eXuerebt, Mauro Paternostrob, Angelo Bassic,d,∗ aInstitut f¨urTheoretische Physik, Eberhard-Karls-Universit¨atT¨ubingen, 72076 T¨ubingen,Germany bCentre for Theoretical Atomic,Molecular, and Optical Physics, School of Mathematics and Physics, Queen's University, Belfast BT7 1NN, United Kingdom cDepartment of Physics,University of Trieste, Strada Costiera 11, 34151 Trieste,Italy dIstituto Nazionale di Fisica Nucleare, Trieste Section, Via Valerio 2, 34127 Trieste, Italy eMax Planck Institute for the Science of Light, Staudtstraße 2, 91058 Erlangen, Germany fInstitute of Optics, Information and Photonics, Friedrich-Alexander University Erlangen-N¨urnberg, Staudtstraße 7 B2, 91058 Erlangen, Germany gScientific Research Unit, Agenzia Spaziale Italiana, Matera, Italy hDepartment of Optics, Palacky University, 17. listopadu 50,772 07 Olomouc,Czech Republic iF´ısica Te`orica: Informaci´oi Fen`omensQu`antics,Department de F´ısica, Universitat Aut`onomade Barcelona, 08193 Bellaterra (Barcelona), Spain jDepartment of Physics and Astronomy, University of Southampton, Highfield Campus, SO17 1BJ, United Kingdom kDeutsches Zentrum f¨urLuft- und Raumfahrt e. V. (DLR), Institut f¨urSatellitengeod¨asieund