“есты по измерению скорости света

“есты по измерению скорости света

Title: Test of the Isotropy of the Speed of Light Using a Continuously Rotating Optical Resonator

Authors: Herrmann, Sven; Senger, Alexander; Kovalchuk, Evgeny; Müller, Holger; Peters, Achim

Affiliation: Institut für Physik, Humboldt-Universität zu Berlin, Hausvogteiplatz 5-7, 10117 Berlin, Germany

Publication: Physical Review Letters, vol. 95, Issue 15, id. 150401 (PhRvL Homepage)

Publication Date: 10/2005

Origin: APS

DOI: 10.1103/PhysRevLett.95.150401

Bibliographic Code: 2005PhRvL..95o0401H

Abstract

We report on a test of Lorentz invariance performed by comparing the resonance frequencies of one stationary optical resonator and one continuously rotating on a precision air bearing turntable. Special attention is paid to the control of rotation induced systematic effects. Within the photon sector of the standard model extension, we obtain improved limits on combinations of 8 parameters at a level of a few parts in 10-16. For the previously least well known parameter we find κ˜ZZe-=(-1.9±5.2)×10-15. Within the Robertson-Mansouri-Sexl test theory, our measurement restricts the isotropy violation parameter β-δ-1/2 to (-2.1±1.9)×10-10, corresponding to an eightfold improvement with respect to previous nonrotating measurements.

Title: Measurement of the single-photon tunneling time

Authors: Steinberg, A. M.; Kwiat, P. G.; Chiao, R. Y.

Affiliation: Department of Physics, University of California, Berkeley, California 94720

Publication: Physical Review Letters, Volume 71, Issue 5, August 2, 1993, pp.708-711 (PhRvL Homepage)

Publication Date: 08/1993

Origin: AIP; APS

DOI: 10.1103/PhysRevLett.71.708

Bibliographic Code: 1993PhRvL..71..708S

Abstract

Using a two-photon interferometer, we have measured the time delay for a photon to tunnel across a barrier consisting of a 1.1-μm-thick 1D photonic band-gap material. The peak of the photon wave packet appears on the far side of the barrier 1.47+/-0.21 fs earlier than it would if it were to travel at the vacuum speed of light c. Although the apparent tunneling velocity (1.7+/-0.2)c is superluminal, this is not a genuine signal velocity, and Einstein causality is not violated. The measured tunneling time is consistent with the group delay (``phase time''), but not with the semiclassical time.

Title: Sound beyond the speed of light: Measurement of negative group velocity in an acoustic loop filter

Authors: Robertson, W. M.; Pappafotis, J.; Flannigan, P.; Cathey, J.; Cathey, B.; Klaus, C.

Affiliation: AA(Department of Physics and Astronomy, Middle Tennessee State University, Murfreesboro, Tennessee 37132), AB(Department of Physics and Astronomy, Middle Tennessee State University, Murfreesboro, Tennessee 37132), AC(Department of Physics and Astronomy, Middle Tennessee State University, Murfreesboro, Tennessee 37132), AD(Siegel High School, Murfreesboro, Tennessee 37129), AE(Siegel High School, Murfreesboro, Tennessee 37129), AF(Blackman High School, Murfreesboro, Tennessee 37128)

Publication: Applied Physics Letters, Volume 90, Issue 1, id. 014102 (3 pages) (2007). (ApPhL Homepage)

Publication Date: 01/2007

Origin: AIP

Keywords: acoustic wave propagation, acoustic filters, tunnelling

DOI: 10.1063/1.2423240

Bibliographic Code: 2007ApPhL..90a4102R

Abstract

The authors describe the experimental observation of negative group velocity propagation of sound waves through an asymmetric loop filter. The characteristics of the filter are established using impulse response and direct tunneling of narrow bandwidth Gaussian pulses. The results confirm recent theoretical predictions that faster-than-light group velocity propagation of sound is possible. Further, the results show that the spectral rephasing achieved in a loop filter is sufficient to produce negative group velocities independent of the phase velocity of the spectral components themselves. Thus, superluminal propagation is realized despite almost six orders of magnitude difference between the speeds of sound and light.

Phys. Rev. Lett. 29, 189 - 192 (1972)

Measurement of an Optical Frequency and the Speed of Light

Z. Bay, G. G. Luther, and J. A. White *

National Bureau of Standards, Washington, D. C. 20234

Received 12 May 1972

We report the measurement of the frequency of the 633-nm red laser line. This is the first measurement of an optical frequency in the visible range without reference to the speed of light or to a measured wavelength. Combination of the optical frequency with the known wavelength yields c to an accuracy higher than previously known. This method demonstrates the practicability of a single-standard time-length measurement system unified via a defined value of the speed of light.

Title: ``Superluminal'' tunneling as a weak measurement effect

Authors: Sokolovski, D.; Msezane, A. Z.; Shaginyan, V. R.

Affiliation: AA(School of Mathematics and Physics, QueenТs University of Belfast, Belfast, BT7 1NN, United Kingdom) AB(Department of Physics and Center for Theoretical Studies of Physical Systems, Clark Atlanta University, Atlanta, Georgia 30314, USA) AC(Petersburg Nuclear Physics Institute, Gatchina 188300, Russia)

Publication:

Physical Review A, vol. 71, Issue 6, id. 064103 (PhRvA Homepage)

Publication Date: 06/2005

Origin: APS

DOI: 10.1103/PhysRevA.71.064103

Bibliographic Code: 2005PhRvA..71f4103S

Abstract

We exploit the analogy between the transfer of a pulse across a scattering medium and AharonovТs weak measurements to resolve the long standing paradox between the impossibility to exceed the speed of light and the seemingly УsuperluminalФ behavior of a tunneling particle in the barrier or a photon in a Уfast-lightФ medium. We demonstrate that superluminality occurs when the value of the duration τ spent in the barrier is uncertain, whereas when τ is known accurately, no superluminal behavior is observed. In all cases only subluminal durations contribute to the transmission which precludes faster-than-light information transfer, as observed in a recent experiment.

Nature 251, 46 (06 September 1974); doi:10.1038/251046a0

Measurement of the speed of light

T. G. BLANEY, C. C. BRADLEY, G. J. EDWARDS, B. W. JOLLIFFE, D. J. E. KNIGHT, W. R. C. ROWLEY, K. C. SHOTTON & P. T. WOODS

National Physical Laboratory, Teddington, Middlesex, UK

WE report here the completion of a determination of the speed of light at the National Physical Laboratory1. The value was obtained from the product of the measured frequency and the wavelength, determined through up-conversion, of the radiation from a CO2 laser stabilised to the R(12) transition of CO2 at 9.3 µm.

Title: Terrestrial and Extraterrestrial Limits on The Photon Mass

Authors: Goldhaber, Alfred S.; Nieto, Michael Martin

Affiliation: AA(Institute for Theoretical Physics, State University of New York at Stony Brook, Stony Brook, New York 11790), AB(The Niels Bohr Institute, University of Copenhagen, Copenhagen, Denmark Department of Physics, University of California, Santa Barbara, California 93106)

Publication Review of Modern Physics, vol. 43, Issue 3, pp. 277-296 (RvMP Homepage)

Publication Date: 07/1971

Origin: APS

Comment: A&AA ID. AAA006.022.061

DOI: 10.1103/RevModPhys.43.277

Bibliographic Code: 1971RvMP...43..277G

Abstract

We give a review of methods used to set a limit on the mass μ of the photon. Direct tests for frequency dependence of the speed of light are discussed, along with more sensitive techniques which test Coulomb's Law and its analog in magnetostatics. The link between dynamic and static implications of finite μ is deduced from a set of postulates that make Proca's equations the unique generalization of Maxwell's. We note one hallowed postulate, that of energy conservation, which may be tested severely using pulsar signals. We present the merits of the old methods and of possible new experiments, and discuss other physical implications of finite μ. A simple theorem is proved: For an experiment confined in dimensions D, effects of finite μ are of order (μD)2-there is no "resonance" as the oscillation frequency ω approaches μ (ℏ=c=1). The best results from past experiments are (a) terrestrial measurements of c at different frequencies μ<=2×10-43 g≡7×10-6 cm-1≡10-10 eV (b) measurements of radio dispersion in pulsar signals (whistler effect) μ<=10-44 g≡3×10-7 cm-1≡6×10-12 eV (c) laboratory tests of Coulomb's law μ<=2×10-47 g≡6×10-10 cm-1≡10-14 eV (d) limits on a constant "external" magnetic field at the earth's surface μ<=4×10-48 g≡10-10 cm-1≡3×10-15 eV. Observations of the Galactic magnetic field could improve the limit dramatically.

Title: Test of relativistic time dilation with fast optical atomic clocks at different velocities

Authors: Reinhardt, Sascha; Saathoff, Guido; Buhr, Henrik; Carlson, Lars A.; Wolf, Andreas; Schwalm, Dirk; Karpuk, Sergei; Novotny, Christian; Huber, Gerhard; Zimmermann, Marcus; Holzwarth, Ronald; Udem, Thomas; Hänsch, Theodor W.; Gwinner, Gerald

Publication: Nature Physics, Volume 3, Issue 12, pp. 861-864 (2007).

Publication Date: 12/2007

Origin: NATURE

DOI: 10.1038/nphys778

Bibliographic Code: 2007NatPh...3..861R

Abstract

Time dilation is one of the most fascinating aspects of special relativity as it abolishes the notion of absolute time. It was first observed experimentally by Ives and Stilwell in 1938 using the Doppler effect. Here we report on a method, based on fast optical atomic clocks with large, but different Lorentz boosts, that tests relativistic time dilation with unprecedented precision. The approach combines ion storage and cooling with optical frequency counting using a frequency comb. 7Li+ ions are prepared at 6.4% and 3.0% of the speed of light in a storage ring, and their time is read with an accuracy of 2×10-10 using laser saturation spectroscopy. The comparison of the Doppler shifts yields a time dilation measurement represented by a Mansouri-Sexl parameter , consistent with special relativity. This constrains the existence of a preferred cosmological reference frame and CPT- and Lorentz-violating `new' physics beyond the standard model.

Title: Probing brane-world scenarios with vacuum refraction of light using gamma-ray bursts

Authors: Gogberashvili, Merab; Sakharov, Alexander S.; Sarkisyan, Edward K. G.

Affiliation: AA(Andronikashvili Institute of Physics, 6 Tamarashvili St., Tbilisi 0177, Georgia), AB(Theory Division, Physics Department, CERN, 1211 Geneva 23, Switzerland; Swiss Institute of Technology, ETH-Zurich, 8093 Zurich, Switzerland), AC(EP Division, Physics Department, CERN, 1211 Geneva 23, Switzerland; School of Physics and Astronomy, The University of Manchester, Manchester M13 9PL, UK)

Publication: Physics Letters B, Volume 644, Issue 2-3, p. 179-185.

Publication Date: 01/2007

Origin: ELSEVIER

Abstract Copyright: Elsevier B.V.

DOI: 10.1016/j.physletb.2006.11.039

Bibliographic Code: 2007PhLB..644..179G

Abstract

We argue that in fat brane-world scenarios the light propagating in vacuum will, because of massive УKaluza KleinФ (KK) excitations, experience a refraction. The motion of a photon inside a fat brane can be decomposed in the longitudinal and transverse directions with respect to the surface of the brane. Since the light observable propagation is related only with the longitudinal motion, the observed speed of light depends on the value of the momentum transverse fraction contributing as the massive KK excitations. This is directly connected with the energy of the particles emitting the light, and hence with the frequency of the light itself. Using recent results on the arrival times of radiation of different energies from the measurements of gamma-ray bursters with known redshifts, we establish the limit M>620 TeV on the inverse thickness of the brane, and thus on the masses of the KK excitations. This limit exceeds by at least one order of magnitude the typical energy scale currently in use to characterize brane phenomena in the realm of future colliders.

Title: Measurement of the speed of light. I - Introduction and frequency measurement of a carbon dioxide laser. II - Wavelength measurements and conclusion

Authors: Blaney, T. G.; Bradley, C. C.; Edwards, G. J.; Jolliffe, B. W.; Knight, D. J. E.; Rowley, W. R. C.; Shotton, K. C.; Woods, P. T.

Affiliation: AA(Aeronautical Research Council, National Physical Laboratory, Teddington, Middx., England), AB(Aeronautical Research Council, National Physical Laboratory, Teddington, Middx., England), AC(Aeronautical Research Council, National Physical Laboratory, Teddington, Middx., England), AD(Aeronautical Research Council, National Physical Laboratory, Teddington, Middx., England), AE(Aeronautical Research Council, National Physical Laboratory, Teddington, Middx., England), AF(Aeronautical Research Council, National Physical Laboratory, Teddington, Middx., England), AG(Aeronautical Research Council, National Physical Laboratory, Teddington, Middx., England), AH(Aeronautical Research Council, National Physical Laboratory, Teddington, Middx., England)

Publication: Royal Society (London), Proceedings, Series A, vol. 355, no. 1680, June 30, 1977, p. 61-114.

Publication Date: 06/1977

Category: Lasers and Masers

Origin: STI

NASA/STI Keywords: CARBON DIOXIDE LASERS, FREQUENCY MEASUREMENT, LASER APPLICATIONS, LIGHT SPEED, OPTICAL MEASUREMENT, VELOCITY MEASUREMENT, HCN LASERS, INTERFEROMETRY, MEASURING INSTRUMENTS, NONLINEAR OPTICS

Bibliographic Code: 1977RSPSA.355...61B

Abstract

The paper reports on a determination of the speed of light made by measuring the frequency and wavelength of radiation from a CO2 laser operated in the 9.3-micron L(12) transition and stabilized by reference to fluorescence in an external CO2 absorption cell. A frequency of 32,176,079,482 plus or - 14 kHz is calculated from a measurement involving the use of an HCN laser, an H2O laser, a microwave oscillator, an upconversion technique based on optical mixing in a nonlinear crystal, and Fabry-Perot interferometry. An optical upconversion technique, Fabry-Perot interferometry, pressure scanning, a servocontrol method, and reference to an iodine-stabilized 633-nm HeNe laser are employed to determine a free-space vacuum wavelength of 9,317,246,348 plus or - 13 FM for the CO2 laser emission. The measured frequency and wavelength values are multiplied together to yield a value for the speed of light of 299,792,459.0 plus or - 0.6 m/s. This result is shown to be in clear agreement with the internationally recommended and adopted value.

Title: Relativistic entanglement and Bell's inequality

Authors: Ahn, Doyeol; Lee, Hyuk-Jae; Moon, Young Hoon; Hwang, Sung Woo

Affiliation: Institute of Quantum Information Processing and Systems, University of Seoul, Seoul 130-743, Korea

Publication: Physical Review A, vol. 67, Issue 1, id. 012103 (PhRvA Homepage)

Publication Date: 01/2003

Origin: APS

DOI: 10.1103/PhysRevA.67.012103

Bibliographic Code: 2003PhRvA..67a2103A

Abstract

In this paper, the Lorentz transformation of entangled Bell states seen by a moving observer is

studied. The

calculated Bell

observable for four

joint measurements

turns out to give a

universal value,

<â⊗b̂>+<â⊗b'>+<a'⊗b̂>-

<a'⊗b'>=(2/(2- β2))(1+(1-

β2)), where â,b̂ are the relativistic

spin observables derived from the Pauli-Lubanski pseudovector and

β=(v/c). We found that the degree of violation of the BellТs inequality is decreasing with increasing velocity of the observer and BellТs inequality is satisfied in the ultrarelativistic limit where the boost speed reaches the speed of light.

Title: The mass of the photon

Authors: Tu, Liang-Cheng; Luo, Jun; Gillies, George T.

Affiliation: AA(Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China ), AB(Department of Physics, Huazhong University of Science and Technology, Wuhan 430074, People's Republic of China ; ), AC(School of Engineering and Applied Science, University of Virginia, Charlottesville, VA 22904, USA)

Publication: Reports on Progress in Physics, Volume 68, Issue 1, pp. 77-130 (2005).

Publication Date: 01/2005

Origin: IOP

DOI: 10.1088/0034-4885/68/1/R02

Bibliographic Code: 2005RPPh...68...77T

Abstract

Because classical Maxwellian electromagnetism has been one of the cornerstones of physics during the past century, experimental tests of its foundations are always of considerable interest. Within that context, one of the most important efforts of this type has historically been the search for a rest mass of the photon. The effects of a nonzero photon rest mass can be incorporated into electromagnetism straightforwardly through the Proca equations, which are the simplest relativistic generalization of Maxwell's equations. Using them, it is possible to consider some far-reaching implications of a massive photon, such as variation of the speed of light, deviations in the behaviour of static electromagnetic fields, longitudinal electromagnetic radiation and even questions of gravitational deflection. All of these have been studied carefully using a number of different approaches over the past several decades. This review attempts to assess the status of our current knowledge and understanding of the photon rest mass, with particular emphasis on a discussion of the various experimental methods that have been used to set upper limits on it. All such tests can be most easily categorized in terms of terrestrial and extra-terrestrial approaches, and the review classifies them as such. Up to now, there has been no conclusive evidence of a finite mass for the photon, with the results instead yielding ever more stringent upper bounds on the size of it, thus confirming the related aspects of Maxwellian electromagnetism with concomitant precision. Of course, failure to find a finite photon mass in any one experiment or class of experiments is not proof that it is identically zero and, even as the experimental limits move more closely towards the fundamental bounds of measurement uncertainty, new conceptual approaches to the task continue to appear. The intrinsic importance of the question and the lure of what might be revealed by attaining the next decimal place are as strong a draw on this question as they are in any other aspect of precise tests of physical laws.

Title: Wigner-Yanase Skew Information and Uncertainty Relations

Authors: Luo, Shunlong

Affiliation: Academy of Mathematics and System Sciences, Chinese Academy of Sciences 100080 Beijing, People's Republic of China and Institut für Experimentalphysik, Universität Wien, 1090 Wien, Austria

Publication: Physical Review Letters, vol. 91, Issue 18, id. 180403 (PhRvL Homepage)

Publication Date: 10/2003

Origin: APS

DOI: 10.1103/PhysRevLett.91.180403

Bibliographic Code: 2003PhRvL..91r0403L

Abstract

The Wigner-Araki-Yanase theorem puts a limitation on the measurement of observables in the presence of a conserved quantity, and the notion of Wigner-Yanase skew information quantifies the amount of information on the values of observables not commuting with the conserved quantity. We demonstrate that the statistical idea underlying the skew information is the Fisher information in the theory of statistical estimation. A quantum Cramér-Rao inequality and a new uncertainty relation in terms of the skew information are established, which shed considerable new light on the relationships between quantum measurement and statistical inference. The result is applied to estimating the evolution speed of quantum states.

Title: Measurement of the Speed of Light. II. Wavelength Measurements and Conclusion

Authors: Blaney, T. G.; Bradley, C. C.; Edwards, G. J.; Jolliffe, B. W.; Knight, D. J. E.; Rowley, W. R. C.; Shotton, K. C.; Woods, P. T.

Publication: Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, Volume 355, Issue 1680, pp. 89-114

Publication Date: 06/1977

Origin: JSTOR

Bibliographic Code: 1977RSPSA.355...89B

Abstract

Wavelength measurements have been carried out on the radiation at 9.3 μ m from a stabilized CO2 laser. The wavelength in vacuum was determined as 9 317 246 348 femtometres (fm), with a standard error of the mean of 11 fm (1.14 parts in 109) and a total systematic uncertainty of ± 13 fm (± 1.4 parts in 109). An upconversion technique of optical mixing in a non-linear crystal was used, so that the interferometric wavelength measurement was carried out on visible difference-frequency radiation at 679 nm. Its wavelength was determined relative to that of an iodine-stabilized He-Ne laser at 633 nm, by using plane-parallel Fabry-Perot interferometers. When combined with the result of the frequency measurement described in part I, this wavelength measurement leads to a value for the speed of light in vacuum of 299 792 459.0 ± 0.6 m/s (Blaney et al. 1974). This result is in agreement (within the quoted uncertainties) with the value recommended internationally by the 14th General Conference of Weights and Measures in 1975.

Title: Probing the Light Speed Anisotropy with Respect to the Cosmic Microwave Background Radiation Dipole

Authors: Gurzadyan, V. G.; Bocquet, J.-P.; Kashin, A.; Margarian, A.; Bartalini, O.; Bellini, V.; Castoldi, M.; D'Angelo, A.; Didelez, J.-P.; di Salvo, R.; Fantini, A.; Gervino, G.; Ghio, F.; Girolami, B.; Giusa, A.; Guidal, M.; Hourany, E.; Knyazyan, S.; Kouznetsov, V.; Kunne, R.; Lapik, A.; Levi Sandri, P.; Lleres, A.; Mehrabyan, S.; Moricciani, D.; Nedorezov, V.; Perrin, C.; Rebreyend, D.; Russo, G.; Rudnev, N.; Schaerf, C.; Sperduto, M.-L.; Sutera, M.-C.; Turinge, A.

Affiliation: AA(ICRA, Dipartimento di Fisica, Università "La Sapienza", 00185 Roma, Italy), AB(IN2P3, Laboratory for Subatomic Physics and Cosmology, 38026 Grenoble, France), AC(Yerevan Physics Institute, 375036 Yerevan, Armenia), AD(Yerevan Physics Institute, 375036 Yerevan, Armenia), AE(INFN sezione di Roma II and Università "Tor Vergata", 00133 Roma, Italy), AF(INFN sezione di Catania and Università di Catania, 95100 Catania, Italy), AG(INFN sezione di Genova and Università di Genova, 16146 Genova, Italy), AH(INFN sezione di Roma II and Università "Tor Vergata", 00133 Roma, Italy), AI(IN2P3, Institut de Physique Nucléaire, 91406 Orsay, France), AJ(INFN sezione di Roma II and Università "Tor Vergata", 00133 Roma, Italy), AK(INFN sezione di Roma II and Università "Tor Vergata", 00133 Roma, Italy), AL(INFN sezione di Torino and Università di Torino, 10125 Torino, Italy), AM(INFN sezione di Roma I and Istituto Superiore di Sanità, 00161 Roma, Italy), AN(INFN sezione di Roma I and Istituto Superiore di Sanità, 00161 Roma, Italy), AO(INFN sezione di Catania and Università di Catania, 95100 Catania, Italy), AP(IN2P3, Institut de Physique Nucléaire, 91406 Orsay, France), AQ(IN2P3, Institut de Physique Nucléaire, 91406 Orsay, France), AR(Yerevan Physics Institute, 375036 Yerevan, Armenia), AS(Institute for Nuclear Research, 117312 Moscow, Russia), AT(IN2P3, Institut de Physique Nucléaire, 91406 Orsay, France), AU(Institute for Nuclear Research, 117312 Moscow, Russia), AV(INFN Laboratori Nazionali di Frascati, 00044 Frascati, Italy), AW(IN2P3, Laboratory for Subatomic Physics and Cosmology, 38026 Grenoble, France), AX(Yerevan Physics Institute, 375036 Yerevan, Armenia), AY(INFN sezione di Roma II and Università "Tor Vergata", 00133 Roma, Italy), AZ(Institute for Nuclear Research, 117312 Moscow, Russia), BA(IN2P3, Laboratory for Subatomic Physics and Cosmology, 38026 Grenoble, France), BB(IN2P3, Laboratory for Subatomic Physics and Cosmology, 38026 Grenoble, France), BC(INFN sezione di Catania and Università di Catania, 95100 Catania, Italy), BD(Institute for Nuclear Research, 117312 Moscow, Russia), BE(INFN sezione di Roma II and Università "Tor Vergata", 00133 Roma, Italy), BF(INFN sezione di Catania and Università di Catania, 95100 Catania, Italy), BG(INFN sezione di Catania and Università di Catania, 95100 Catania, Italy), BH(RRC "Kurchatov Institute", 123182 Moscow, Russia)

Publication: Modern Physics Letters A, Volume 20, Issue 01, pp. 19-28 (2005). (MPLA Homepage)

Publication Date: 00/2005

Origin: WSPC

Keywords: Speed of light, cosmic microwave background, Compton effect

DOI: 10.1142/S0217732305016294

Bibliographic Code: 2005MPLA...20...19G

Abstract

We have studied the angular fluctuations in the speed of light with respect to the apex of the dipole of Cosmic Microwave Background (CMB) radiation using the experimental data obtained with GRAAL facility, located at the European Synchrotron Radiation Facility (ESRF) in Grenoble. The measurements were based on the stability of the Compton edge of laser photons scattered on the 6 GeV monochromatic electron beam. The results enable one to obtain a conservative constraint on the anisotropy in the light speed variations Δc(θ)/c<3×10-12, i.e. with higher precision than from previous experiments.

Title: The Measurement of Velocity by Applying Schlieren-Interferometry to Doppler-Shifted Laser Light

Authors: Schwar, M. J. R.; Weinberg, F. J.

Publication: Proceedings of the Royal Society of London. Series A, Mathematical and Physical Sciences, Volume 311, Issue 1506, pp. 469-476

Publication Date: 07/1969

Origin: JSTOR

Bibliographic Code: 1969RSPSA.311..469S

Abstract

A method is developed in which light from a laser, after being reflected, refracted, or diffracted in one selected direction by any moving solid or phase object (including particles, flames or pressure waves) is isolated by a 'schlieren aperture' and then allowed to interfere with an unperturbed beam. The Doppler shift in wavelength manifests itself as a beat frequency which is related theoretically to the passage of interference fringes past a small photodetector. The theoretical analysis examines various practical limitations and suggests experimental refinements. The method has been applied to moving grids, ultrasonics, flames and particles at velocities ranging from a few centimetres per second to the speed of sound.

Title: Review - Laser wavelength measurements and the speed of light

Authors: Rowley, W. R. C.; Jolliffe, B. W.; Shotton, K. C.; Wallard, A. J.; Woods, P. T.

Publication: Optical and Quantum Electronics, vol. 8, Jan. 1976, p. 1-14.

Publication Date: 01/1976

Category: Optics

Origin: STI

NASA/STI Keywords: FREQUENCY MEASUREMENT, LASER APPLICATIONS, LIGHT SPEED, OPTICAL MEASUREMENT, VELOCITY MEASUREMENT, WAVELENGTHS, BUREAUS (ORGANIZATIONS), CARBON DIOXIDE LASERS, HCN LASERS, HELIUM-NEON LASERS, INTERFEROMETRY, METHANE, MICROWAVE FREQUENCIES, MIM (SEMICONDUCTORS)

Bibliographic Code: 1976OptQE...8....1R

Abstract

Measurement of the speed of light is reviewed for two broad classes of measuring techniques: time-of-flight techniques where a light pulse is timed over a measured distance and techniques where the wavelength and frequency of an oscillator are measured. A brief historical review of the more significant early measurements and the limitations of the techniques is presented. It was not until the development of lasers and the nonlinear optical techniques made possible by their high output intensities that frequency measurements could be extended to the visible region of the spectrum. Experimental results are compared and discussed, which have resulted in the new value for the speed of light recommended by CCDM and endorsed by other international organizations.

Title: Investigation of time-resolved single detector Doppler global velocimetry using sinusoidal laser frequency modulation

Authors: Fischer, Andreas; Büttner, Lars; Czarske, Jürgen; Eggert, Michael; Grosche, Gesine; Müller, Harald

Affiliation: AA(Faculty of Electrical Engineering and Information Technology, Institute for Fundamentals of Electrical Engineering and Electronics, Chair for Measuring and Testing Techniques, Dresden University of Technology, Helmholtzstr. 18, D-01069 Dresden, Germany ), AB(Faculty of Electrical Engineering and Information Technology, Institute for Fundamentals of Electrical Engineering and Electronics, Chair for Measuring and Testing Techniques, Dresden University of Technology, Helmholtzstr. 18, D-01069 Dresden, Germany ), AC(Faculty of Electrical Engineering and Information Technology, Institute for Fundamentals of Electrical Engineering and Electronics, Chair for Measuring and Testing Techniques, Dresden University of Technology, Helmholtzstr. 18, D-01069 Dresden, Germany ), AD(Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig, Germany), AE(Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig, Germany), AF(Physikalisch-Technische Bundesanstalt, Bundesallee 100, D-38116 Braunschweig, Germany)

Publication: Measurement Science and Technology, Volume 18, Issue 8, pp. 2529-2545 (2007).

Publication Date: 08/2007

Origin: IOP

DOI: 10.1088/0957-0233/18/8/029

Bibliographic Code: 2007MeScT..18.2529F

Abstract

We present a new Doppler global velocimetry (DGV) technique that is based on sinusoidal laser frequency modulation: FM-DGV. DGV is an optical method to measure two-dimensional velocity fields in fluid flows. The measurement principle is based on measuring the Doppler shift of the laser frequency with the use of an absorption cell converting frequency variations into intensity variations. In order to measure the scattered light intensity, conventional DGV systems use a signal and a reference camera. Using the FM-DGV technique, no additional reference camera is required. Thus significant error sources can be eliminated, e.g. image misalignment errors, which can limit the performance of conventional DGV. In this paper, a comparison between both DGV systems and an error analysis of the FM-DGV system is given. The parameter optimization of the FM-DGV is discussed as well. A minimum measured standard deviation of 0.02 m s 1 was achieved. Measurement results of applications to a rotating glass disc as a calibration object, a free jet flow and a laminar boundary layer flow are presented to demonstrate the ability of FM-DGV also for low-speed and unsteady flow conditions.

Title: Gamma-Ray Bursts as Probes for Quantum Gravity

Authors: Piran, T.

Publication: Planck Scale Effects in Astrophysics and Cosmology. Editor: Jurek Kowalski-Glikman, Giovanni Amelino-Camelia, Lecture Notes in Physics, vol. 669, p.351-362

Publication Date: 00/2005

Origin: LNP

DOI: 10.1007/11377306_10

Bibliographic Code: 2005LNP...669..351P

Abstract

Gamma ray bursts (GRBs) are short and intense pulses of γ-rays arriving from random directions in the sky. Several years ago Amelino-Camelia et al. [1] (see also [2]) pointed out that a comparison of time of arrival of photons at different energies from a GRB could be used to measure (or obtain a limit on) possible deviations from a constant speed of light at high photons energies. I review here our current understanding of GRBs and reconsider the possibility of performing these observations (see also Norris, Bonnell, Marani, & Scargle [3] for a review of the same topic). I begin (in Sect. 2) with a brief discussion of the motivation to consider an energy dependent variable speed of light. I turn (in Sect. 3) to a general discussion of the detectability of deviations from a constant speed of light via time-lag measurments. I derive constraints on the Energy range, the distance to the sources and the needed temporal resolution of the sources and the detectors. I then turn (in Sect. 4) to a short description of our current understanding of GRBs. This section is included as a background material as for the rest of the discussion GRBs are just cosmological sources of high energy photons and we don't really care how are these photons they produced. In Sect. 5 I return to the subject of the talk and I describe the temporal structure and spectral properties of GRBs. These are the key issues that are relevant for the observations of a variable speed of light. I conclude (in Sect. 6) by confronting the observations needed for determination of (or obtaining a limit on) a variable speed of light with the properties of GRBs. I discuss some recent attempts to obtain limits on Quantum Gravity effects [4, 5, 6, 7] and prospects for future improvements.

Title: GLAST, GRBs, and Quantum Gravity

Authors: Norris, Jay

Publication: Proceedings of the 26th International Cosmic Ray Conference. August 17-25, 1999. Salt Lake City, Utah, USA. Under the auspices of the International Union of Pure and Applied Physics (IUPAP). Volume 4. Edited by D. Kieda, M. Salamon, and B. Dingus, p.20

Publication Date: 08/1999

Origin: ADS

Bibliographic Code: 1999ICRC....4...20N

Abstract

The fast temporal structures and cosmological distances of gamma-ray bursts (GRBs) afford a natural laboratory for testing theories of frequency-dependent propagation of high-energy photons, as predicted for quantum gravity (QG). We calibrate the sensitivity of the proposed Gamma-ray Large Area Space Telescope (GLAST) by performing simulations which include: the response of GLAST to a GRB fluence distribution; a distribution of spectral power-law indices similar to the EGRET sample; and consideration of γγ attenuation, significant above ~ 10 GeV for redshifts z > 3-5. We find that GLAST should detect > 200 GRBs per year, with sensitivity to a few tens of GeV for a few bursts. GLAST could detect the energy-and distance-dependent dispersion (10 ms / GeV / Gpc) predicted by QG with 1-2 years of observations. Attribution to QG would require correlation of GRB redshifts with the temporal and energetic signatures.

Title: GRB 051221A and tests of Lorentz symmetry

Authors: Rodríguez Martínez, María; Piran, Tsvi; Oren, Yonatan

Affiliation: Racah Institute of Physics, The Hebrew University, 91904 Jerusalem, Israel mrm@phys.huji.ac.il

Publication: Journal of Cosmology and Astroparticle Physics, Issue 05, pp. 017 (2006).

Publication Date: 05/2006

Origin: IOP

DOI: 10.1088/1475-7516/2006/05/017

Bibliographic Code: 2006JCAP...05..017R

Abstract

Various approaches to quantum gravity suggest the possibility of violation of Lorentz symmetry at very high energies. In these cases we expect a modification at low energies of the dispersion relation of photons that contains extra powers of the momentum suppressed by a high energy scale. These terms break boost invariance and can be tested even at relatively low energies. We use the light curves of the very bright short gamma-ray burst GRB 051221A and compare the arrival times of photons at different energies with the expected time delay due to a modified dispersion relation. As no time delay was observed, we set a lower bound of 0.0066 Epl ~ 0.66 × 1017 GeV on the scale of Lorentz invariance violation.

Title: Constraining Lorentz violations with gamma ray bursts

Authors: Rodríguez Martínez, María; Piran, Tsvi

Affiliation: Racah Institute of Physics, The Hebrew University, 91904 Jerusalem, Israel mrm@phys.huji.ac.il

Publication: Journal of Cosmology and Astroparticle Physics, Issue 04, pp. 006 (2006).

Publication Date: 04/2006

Origin: IOP

DOI: 10.1088/1475-7516/2006/04/006

Bibliographic Code: 2006JCAP...04..006R

Abstract

Gamma ray bursts are excellent candidates for constraining physical models which break Lorentz symmetry. We consider deformed dispersion relations which break the boost invariance and lead to an energy-dependent speed of light. In these models, simultaneously emitted photons from cosmological sources reach Earth with a spectral time delay that depends on the symmetry breaking scale. We estimate the possible bounds which can be obtained by comparing the spectral time delays with the time resolution of available telescopes. We discuss the best strategy to reach the strongest bounds. We compute the probability of detecting bursts that improve the current bounds. The results are encouraging. Depending on the model, it is possible to build a detector that within several years will improve the present limits of 0.015 mpl.

Title: A Search in Gamma-Ray Burst Data for Nonconstancy of the Velocity of Light

Authors: Ellis, John; Farakos, K.; Mavromatos, N. E.; Mitsou, V. A.; Nanopoulos, D. V.

Affiliation: AA(Theory Division, CERN, CH-1211 Geneva 23, Switzerland), AB(Department of Physics, National Technical University of Athens, Zografou Campus, GR 157 80 Athens, Greece), AC(Department of Physics, University of Oxford, 1 Keble Road, Oxford OX1 3NP, UK; and Theory Division, CERN), AD(Department of Physics, University of Athens, Panepistimioupolis Zografou GR 157 71 Athens, Greece; and Experimental Physics Division, CERN), AE(Department of Physics, Texas A & M University, College Station, TX 77843-4242 Astroparticle Physics Group, Houston Advanced Research Center; and Academy of Athens, Chair of Theoretical Physics, Division of Natural Sciences)

Publication: The Astrophysical Journal, Volume 535, Issue 1, pp. 139-151. (ApJ Homepage)

Publication Date: 05/2000

Origin: UCP

ApJ Keywords: Gamma Rays: Bursts, Relativity

DOI: 10.1086/308825

Bibliographic Code: 2000ApJ...535..139E

Abstract

We discuss possible tests of the constancy of the velocity of light using distant astrophysical sources such as gamma-ray bursters (GRBs), active galactic nuclei (AGNs), and pulsars. This speculative quest may be motivated by some models of quantum fluctuations in the spacetime background, and we discuss explicitly how an energy-dependent variation in photon velocity δc/c~-E/M arises in one particular quantum-gravitational model. We then discuss how data on GRBs may be used to set limits on variations in the velocity of light, which we illustrate using BATSE and OSSE observations of the GRBs that have recently been identified optically and for which precise redshifts are available. We show how a regression analysis can be performed to look for an energy-dependent effect that should correlate with redshift. The present data yield a limit M>~1015 GeV for the quantum gravity scale. We discuss the prospects for improving this analysis using future data, and how one might hope to distinguish any positive signal from astrophysical effects associated with the sources.

Title: Testing Lorentz Invariance with GRB 021206

Authors: Boggs, Steven E.; Wunderer, C. B.; Hurley, K.; Coburn, W.

Affiliation: AA(Space Sciences Laboratory, University of California at Berkeley, Grizzly Peak at Centennial Drive, Berkeley, CA 94720-7450 boggs@ssl.berkeley.edu; Department of Physics, University of California at Berkeley, 366 LeConte Hall, Berkeley, CA 94720-7300.), AB(Space Sciences Laboratory, University of California at Berkeley, Grizzly Peak at Centennial Drive, Berkeley, CA 94720-7450 boggs@ssl.berkeley.edu), AC(Space Sciences Laboratory, University of California at Berkeley, Grizzly Peak at Centennial Drive, Berkeley, CA 94720-7450 boggs@ssl.berkeley.edu), AD(Space Sciences Laboratory, University of California at Berkeley, Grizzly Peak at Centennial Drive, Berkeley, CA 94720-7450 boggs@ssl.berkeley.edu)

Publication: The Astrophysical Journal, Volume 611, Issue 2, pp. L77-L80. (ApJ Homepage)

Publication Date: 08/2004

Origin: UCP

ApJ Keywords: Gamma Rays: Bursts, Gravitation, Relativity

DOI: 10.1086/423933

Bibliographic Code: 2004ApJ...611L..77B

Abstract

Since the discovery of the cosmological origin of gamma-ray bursts (GRBs), there has been growing interest in using these transient events to probe the quantum gravity energy scale in the range 1016-1019 GeV, up to the Planck mass scale. This energy scale can manifest itself through a measurable modification in the electromagnetic radiation dispersion relation for high-energy photons originating from cosmological distances. We have used data from the GRB of 2002 December 6 (GRB 021206) to place an upper bound on the energy dispersion of the speed of light. The limit on the first-order quantum gravity effects derived from this single GRB indicates that the energy scale is in excess of 1.8×1017 GeV. We discuss a program to further constrain the energy scale by systematically studying such GRBs.