Where results make sense

About us   |   Why use us?   |   Reviews   |   PR   |   Contact us

THE SAGNAC EFFECT Sagnac rotated his turntable at two revolutions per second and found the expected effect; that is, he demonstrated that absolute rotation could be measured. All of these variations agree with Sagnac's original result.(10) Still another variation was that of Dufour and Prunier who kept the light source and observer separated from and not moving with the turntable on which the mirrors were mounted.(11) Their result was the same as Sagnac's. The effect of the Earth's gravitational field manifests itself when the interferometer crystal is rotated around a horizontal axis in such a way that one beam path experiences a higher gravitational potential [energy] that the other. www.ldolphin.org /sagnac.html   (982 words)

Sagnac effect - Wikipedia, the free encyclopedia The Sagnac effect is the electromagnetic counterpart of the dynamics of rotation. Its purpose was to detect "the effect of the relative motion of the ether". It is independent of the choice of reference frame, as is shown by a calculation that invokes the metric tensor for an observer at the axis of rotation of the ring interferometer and rotating with it yielding the same outcome. en.wikipedia.org /wiki/Sagnac_effect   (1858 words)

The Sagnac Effect It's worth emphasizing that the Sagnac effect is purely a classical, not a relativistic phenomenon, because it's a "differential device", i.e., by running the light rays around the loop in opposite directions and measuring the time difference, it effectively cancels out the "transverse" effects characteristic of truly relativistic phenomenon. The only significance of the Sagnac effect for special relativity (aside from providing another refutation of ballistic theories) is that although the effect itself is of the first order in v/c, the qualitative description of the local conditions on the disk in terms of inertial coordinates depends on second-order effects. Considering the Earth as a particle on a large Sagnac device as it orbits around the Sun, the ether drift experiments demonstrate these second-order effects, confirming that the speed of light is indeed invariant with respect to relatively moving systems of inertial coordinates. www.mathpages.com /rr/s2-07/2-07.htm   (3502 words)

Common Sense and Modern Physics   (Site not responding. Last check: 2007-10-15) Simply stated, the motion of the detector (observer) has no effect on the speed of light; and therefore a non-isotropic light speed relative to the moving detector can be expected—which leads to the observed phenomenon. However, the most common explanation which I have found in the literature [1], and apparently the one to which Einstein himself subscribed, is that the path around the circumference should be unwrapped into a straight-line path and the Lorentz transformation from the stationary to moving frame applied to this unwrapped moving circumference. In the GPS context, this effect is referred to as the one-way Sagnac effect and is blamed upon the rotation of the earth. www.egtphysics.net /Sagnac.htm   (919 words)

Spartanburg SC | GoUpstate.com | Spartanburg Herald-Journal   (Site not responding. Last check: 2007-10-15) The Sagnac effect, named after French physicist Georges Sagnac, is a phenomenon encountered in interferometry that is elicited by rotation. The Sagnac effect is the electromagnetic counterpart of the mechanics of rotation. Its purpose was to detect "the effect of the relative motion of the ether". www.goupstate.com /apps/pbcs.dll/section?category=NEWS&template=wiki&text=Sagnac_interferometer   (1848 words)

PHYSICAL OPTICS, THE SAGNAC EFFECT, AND THE AHARONOV BOHM In Section 3 we shown that the Tomita Chao effect is a Sagnac effect with several loops, and is a shift in the Cartan tetrad of the Evans unified field theory. The effect (81) is observed experimentally {12} as a shift in the interferogram of the Young interferometer, a shift caused by the iron whisker. In the same type of analogy the Sagnac effect is a rotational effect caused by a physical rotation of the platform with respect to a fixed reference frame, whereas in the AB effect the magnetic field is a rotation or spin of spacetime (the reference frame itself). www.mathematik.tu-darmstadt.de /~bruhn/PHYSICAL_OPTICS1.htm   (8487 words)

Relativity and GPS   (Site not responding. Last check: 2007-10-15) These are: (1) the effect of source velocity (GPS satellite) and receiver velocity upon the satellite and receiver clocks; (2) the effect of the gravitational potential upon satellite and receiver clocks; and (3) the effect of receiver motion upon the signal reception time (Sagnac effect). The Sagnac effect is the result of a non-isotropic speed of light and arises any time an observer or measuring instrument moves with respect to the frame chosen as the isotropic light-speed frame. The effect of velocity on the rate at which clocks run is not consistent with the special-theory predictions that it should be a function of relative velocity between source and receiver. www.egtphysics.net /GPS/RelGPS.htm   (10670 words)

Canterbury Ring Laser Project - Physics and Astronomy - University of Canterbury - New Zealand Sagnac had the prescience to suggest that this could be used to measure the motion of a vehicle, in his case a ship. The Sagnac effect is much greater for the quantum waves of matter, since light goes so fast as to give the Earth little chance to rotate in one of its circuits. The reason for this is that in an active device, with a light amplifier, the phase shift is spontaneously neutralised; the Sagnac effect is reincarnated as a frequency difference between the two light beams. www.phys.canterbury.ac.nz /research/laser/ring_open.shtml   (1664 words)

F.A.Q about Experimental Tests Invalidating Einstein's Relativity The Sagnac effect on the GPS Clock synchronization is extremely important. This is not only in perfect agreement with the Sagnac experiments, but also agrees with the results expected from an absolute frame of reference, in which light is traveling at velocity c with respect to a fixed frame at rest. The measured velocity of light is compatible with a fixed frame of reference, either using the circular trajectory of light as done using the Sagnac experiment or using the velocity of light after reflection on a mirror. www.newtonphysics.on.ca /faq/invalidation.html   (3049 words)

The Rotating Interferometer,   (Site not responding. Last check: 2007-10-15) In both of these proofs, it was shown that the Sagnac effect is due to a change in path length, with no role ascribed to Doppler. Referring to the RCM theory [1], one sees that the Doppler effect at an arbitrary angle of incidence is given by the relative velocity of the source at the time of emission to that of the observer at the time of reception. It is easiest to calculate the effect by breaking the velocity into one component along the aberrated line-of-sight from the observer, and the other normal to the first. renshaw.teleinc.com /papers/drisco/drisco.stm   (1140 words)

General relativity in the global positioning system However because the earth rotates, this is prevented by the Sagnac effect, which is large enough in the GPS to be significant. This is a combination of five different sources of relativistic effects: gravitational frequency shifts of ground clocks due to earth's monopole and quadrupole moments, gravitational frequency shifts of the satellite clock, and second-order Doppler shifts from motion of satellite and earth-fixed clocks. Several relativistic effects are too small to affect the system at current accuracy levels, but may become important as the system is improved; these include gravitational time delays, frequency shifts of clocks in satellites due to earth's quadrupole potential, and space curvature. www.phys.lsu.edu /mog/mog9/node9.html   (1307 words)

Special Relativity Right or Wrong The circuit does not have to be as large as the cross section of the Earth to detect this effect. A Frenchman, Sagnac, found in 1914 that light signals go around a disc of 1 m diameter faster against the spin of the disc than in the direction of the spin. This was a Sagnac test on a disc of diameter 9,500,000 m diameter (the diameter of the Earth at that latitude). www.engology.com /articlerelativity.htm   (1340 words)

View topic - SR Predictions of Sagnac and Wang To explain the sagnac effect they then say that there must be a kinematic shift occuring because the emitter is moving wrt the center point of the coordinate system created by its parts. The sagnac effect detected was relational to the linear speed of the cable. Firstly the sagnac effect was 1913 and was an embarassment to SR at the time and Einstein at one time previously believed that the effect was impossible. www.anti-relativity.com /forum/post-272.html   (11350 words)

The Global Positioning System (GPS) Most of the effect is purposely removed by slightly offsetting the satellite clocks in frequency prior to launch, the so-called "factory offset" of the clock. The net effect of relativity for a zero eccentricity GPS satellite is a combination of effects caused by satellites velocity (Special Relativity effect) and Earth gravitational field (General Relativity effect). Because Earth rotates, Sagnac effect is large enough in the GPS and the clocks can’t be synchronized in the rotating frame and there is necessity for different approach to synchronize the clocks. physics.syr.edu /courses/PHY312.03Spring/GPS/GPS.html   (2645 words)

World's largest ring laser gyro   (Site not responding. Last check: 2007-10-15) Stedman: The Sagnac effect in a ring laser is the frequency difference that arises between counterrotating modes when the whole system is rotating. In October 1991, the Sagnac frequency was first observed in C I; the ring did unlock with the earth's rotation. For example, this can be a physical rotation as in the original Sagnac effect, or it could be the effect of an external magnetic field on some medium, sufficient in principle to induce a nonreciprocal refractive index without any rotation. www.spie.org /web/oer/september/sep96/gyro.html   (2521 words)

Absolute zero-velocity measured in Sagnac Effect - Science Forums, The Original The original Sagnac Effect has photons traveling in opposite directions around a circular path The circle is turning and therefore the photons do not arrive at the physical emission point simultaneously. As one of you links notes, GPS and geostationary satellites that have to account for earth rotation via the Sagnac effect do not have to account for the linear effect due to the earth's motion, to which they would be very sensitive. It was discoverd that the SE is not just a rotational effect, it is in effect concerning the velocity of moving measuring devices and the relative speed of frame and photon that is not measured as C always. www.scienceforums.net /forum/showthread.php?t=11074   (9556 words)

Sagnac's effect - SciForums.com The Sagnac effect detects acceleration due to rotation. Whereas you can't do any experiment to tell whether your windowless room is travelling in a straight line at constant speed, there are many experiments you can do to determine if it is rotating or not. The Sagnac effect is used in laser ring gyros and fibre-optic gyros. www.sciforums.com /showthread.php?t=36746   (158 words)

Holism That there is a medium was proven in 1913 by Georges Sagnac, a French physicist, who modified the Michelson-Morley experiment so that instead of doubling the path of the light beam back upon itself, directed a split beam of light around the edge of a 20-inch turntable. Since the Sagnac effect was used to develop the optical gyroscopes that are widely employed in navigation, there is no question of its validity. This also has the same effect on the equilibration rate of other fields, and this effect on the equilibration of fields of lesser bodies causes them to move spontaneously to remain centered. www.non-newtonianphysics.com /holism.htm   (2851 words)

Sagnac effect, twin paradox and space-time topology   (Site not responding. Last check: 2007-10-15) We discuss the Sagnac effect in standard Minkowski coordinates and with an alternative synchronization convention. We propose a closed Minkowski space-time as an exact equivalent to the rim of a disk, both in the rotating and non-rotating case. In this way the Sagnac effect can be explained as being purely topological, neglecting the radial acceleration altogether. www.jive.nl /~wucknitz/publications/pub.php?sagnac2004   (293 words)

Sagnac Effect: A Simple Description But before we look at the effect as seen by an observer moving with the disk, we need a little background, and we'll also look at a direct calculation of the effect from the point of view of a stationary (non-rotating) observer. As Sagnac found in 1913, the transit time is no longer the same in the two directions -- the signal traveling "with" the direction of the spin takes longer to go around the disk than the signal traveling "against" the direction of spin (see figure 2). The same effect can be used at larger scales (with large rings and interferometers) to detect even very slow rotation, such as that of the Earth. www.physicsinsights.org /sagnac_1.html   (2617 words)

Theory of Relativity, Part 1: Special Relativity - Numericana The Harress-Sagnac effect used to measure rotation with fiber optic cable. The Sagnac effect was actually first dreamt of by Albert A. Michelson in 1904. This relation was proposed by Einstein (1905) in his explanation of the laws of the photoelectric effect (for which he received the Nobel Prize in 1921) which may be construed as a formal discovery of the photon... home.att.net /~numericana/answer/relativity.htm   (4330 words)

Paradoxes Resolved, Origins Illuminated - Michelson-Morley experiments First, Sagnac experiments are the same as MM experiments, except that they are conducted on a rotating platform. Meta Research's position is that both the relativity of motion and the effect of gravitational potential on clocks are well-established. The time dilation and frame contraction, predicted by SR are second order effects and become significant with speeds approaching the speed of light. www.metaresearch.org /msgboard/topic.asp?TOPIC_ID=247   (1537 words)

Anti Relativity : Sagnac Effect is one of the strongest evidences against relativity Anti Relativity : Sagnac Effect is one of the strongest evidences against relativity Also known as the Sagnac effect, the results are an uncontested fact, the interpretation is far from it. They do also mention that the Sagnac Effect does cause a Doppler shift in frequency which it should not if relativity were true. www.anti-relativity.com /sagnac.htm   (721 words)

2 Reference Frames and the Sagnac Effect The Sagnac effect can be regarded as arising from the relativity of simultaneity in a Lorentz transformation to a sequence of local inertial frames co-moving with points on the rotating earth. The Sagnac effect is very important in making such comparisons, as it can amount to hundreds of nanoseconds, depending on the geometry. The actual mean value of the residual obtained after adding the three pairs of time differences was 5 ns, which was less than 2 percent of the magnitude of the calculated total Sagnac effect [4]. relativity.livingreviews.org /Articles/lrr-2003-1/node2.html   (1337 words)

Sagnac Effect The Sagnac effect and related topics are discussed in detail and expounded within the framework of the Emission Theory of light. To treat the Sagnac effect according to the Emission Theory, the Stewart-Thomson law of reflection is required. This experiment is identical to the Sagnac Experiment in the case of rotating source and detector, except the earth here plays the role of the rotating Sagnac disc. www.wbabin.net /physics/faraj6.htm   (2845 words)

Sagnac interferometer The Sagnac effect is the relative phase shift between two beams of light that have traveled an identical path in opposite direction in a rotating frame. The Sagnac effect is a relativistic effect but can be understood with a simple picture (see Fig. Figure: (a) Schematic setup of a Sagnac interferometer and its modification for magneto-optical measurements in transmission (Faraday effect) or reflection (Kerr effect), respectively. www.physik.fu-berlin.de /~bauer/habil_online/node11.html   (602 words)

Rotation rate measuring instrument - Patent 4573795 In the embodiment in which the light paths are formed by optical waveguides embedded in a sealing compound, the influence of disturbing effects on the quantities entering the measurement is small. Their intensities are I.sub.1=k.multidot.cos.sup.2.phi.s/2 and I.sub.2 =k.multidot.sin.sup.2.phi.s/2, where k is a constant, and.phi..sub.s is the phase shift between the two component beams due to the Sagnac effect, which will be dealt with later. During measurement, switching is effected at the frequency F.sub.S between the modulating signals f1 and f2; during calibration, switching is effected at the frequency F.sub.S between the modulating signals f1 and f3. www.freepatentsonline.com /4573795.html   (4456 words)

Experimental Basis of Special Relativity The Doppler effect is the observed variation in frequency of a source when it is observed by a detector that is moving relative to the source. This effect is most pronounced when the source is moving directly toward or away from the detector, and in pre-relativity physics its value was zero for transverse motion (motion perpendicular to the source-detector line). The experiments are marred by two clear instrumentation effects: there is almost certainly feedback into the laser in at least the first paper (and quite probably in the others), and the multi-mode lasers employed could mimic the effect seen due to the interrelationships among the different modes. math.ucr.edu /home/baez/physics/Relativity/SR/experiments.html   (7342 words)

A New Worldview.htm The Sagnac effect has since been used to develop optical gyroscopes which are widely employed in navigation, so there is no question of its validity. The effect of motion being a state was that a moving body no longer needed any participation by the space through which it travels. Because of its application to technology, the effect from altering the natural kinetics was translated to energy, the most important concept in physics. www.non-newtonianphysics.com /anew.htm   (3741 words)

Try your search on: Qwika (all wikis)

About us   |   Why use us?   |   Reviews   |   Press   |   Contact us   Copyright © 2005-2007 www.factbites.com Usage implies agreement with terms.