User:Reddi/Trouton-Noble experiment

The Trouton-Noble experiment was conducted early in the 1900s conducted in 1901–1903 (published in 1903). It was developed by Frederick Thomas Trouton (who also developed the Trouton's ratio) and H. R. Noble. The Trouton-Noble experiment attempted to detect motion of the Earth through the luminiferous aether and attempted to electromagnetically test the effect predicted to be caused by the absolute motion of the Earth through the aether. It was based on a suggestion by George FitzGerald that a charged parallel-plate capacitor moving through the aether should orient itself perpendicular to the motion.

Some recent Trouton Noble experiment which, properly controlled, obtained positive results. Confirmation by having the experiments repeated by an third-party independent group have not proceeded. The 1903 experiment obtained a null result: no motion relative to the aether could be detected. Such experimental results are now seen, consistent with special relativity, to reflect the constancy of the speed of light and the absence of any absolute rest frame (or aether). The recent (1998) controversial claims of a positive result by Cornille et. al are described below.

Contents

1 Historical experiments 2 Recent experiment 3 Disadvantages 4 Equivalents 5 Futher reading and offline references 6 External links and online references

Historical experiments

The detailed relativistic analysis of the null result requires care to correctly reconcile, for example, the effects seen by observers in different frames of reference (see e.g. Teukolsky, 1996 and Jefimenko, 1999), but ultimately all such theoretical descriptions are shown to give the same result. The early history of descriptions of this experiment is reviewed by Janssen (1995).

Lthe earlier Michelson-Morley experiment, Trouton and Noble in the early 1900s obtained a null result: no motion relative to the aether could be detected. This null result was reproduced, with increasing sensitivity, by Chase in 1927 and Hayden in 1994. Such experimental results are now seen, consistent with special relativity, to reflect the constancy of the speed of light and the absence of any absolute rest frame (or aether).

Recent experiment

In the experiment, a suspended parallel plate capacitor is held by a fine torsion fiber and is charged. An electromagnetic torque is measured due to magnetic forces since the capacitor is moving through the aether. The experiment determines if the passage of the Earth through the aether could be detected using electrical means.

Modern Trouton and Noble experiments have improved on the sensitivity of the original experiment by using higher voltages and better controlled experimental conditions. Some experimenters claim that even if the aether exists as originally proposed, Trouton and Noble wouldn't have been able to detect it using their apparatus. Recent experiments have not consistently produced a result in favour of the aether. In 1998, Patrick Cornille, Jean-Louis Naudin, and Szames reported a successful duplication of the Trouton Noble experiment using around 70 kV. Thomas Townsend Brown conducted similar experiment with High-Voltage capacitors, earlier, of significant magnitude.

Nieves et al. also predict that a very slight positive result might arise from the interaction with the Earth's magnetic field and its axial rotation; such a result would be quantitatively different from the type originally sought by Trouton and Noble and may explain the result by Cornille (although some believe Cornille's observation was qualitative and not quantitative). However, this explanation is based on standard electromagnetism and relativity.

Disadvantages

Trouton-Noble experiments are notoriously difficult to control. For example, a current flow in the test circuit may cause the device to act as a compass, aligning it with the Earth's magnetic field. For this reason, experiments which do not go to great lengths to rule out alternate explanations cannot be trusted. _{[1] (http://www.angelfire.com/scifi/EclipseLab/2k1/EG/TN.html)} Some experiment which appears to be properly controlled. _{[2] (http://jnaudin.free.fr/html/troutnbl.htm) [3] (http://citeseer.nj.nec.com/cachedpage/404350/1)} Confirmation by having the experiments repeated by an third-party independent group have not proceeded.

Equivalents

The Michelson-Morley experiment also provides an equivalent test of aether theories, but using optical rather than electrostatic means.

Futher reading and offline references

• Trouton, F. T., and Noble, "The Mechanical Forces acting on a Charged Electric Condenser moving through Space", Philosophical Transactions. Royal Society of London, 1903.
• Laue, M. V., "On electrodynamics of Minkowski of the bodies in motion".
• Butler, J. W., "On the Trouton-Noble Experiment". American Journal of Physics, 1968.
• Teukolsky, Saul A., "The Explanation of the Trouton-Noble Experiment Revisited". American Journal of Physics, April 1996.
• F. T. Trouton and H. R. Noble, "The mechanical forces acting on a charged elecric condenser moving through space," Phil. Trans. Royal Soc. A 202, 165–181 (1903).
• Carl T. Chase, "The Trouton-Noble ether drift experiment," Phys. Rev. 30, 516–519 (1927).
• H. C. Hayden, "High sensitivity Trouton-Noble experiment," Rev. Scientific Instruments 65 (4), 788–792 (1994).
• Saul A. Teukolsky, "The explanation of the Trouton-Noble experiment revisited," Am. J. Physics 64 (9), 1104–1109 (1996).
• P. Cornille, "Correspondence: Making a Trouton-Noble experiment succeed," Galilean Electrodynamics 9 (2), 33 (1998).
• P. Cornille, "A linear Trouton-Noble experiment which shows the violation of Newton's third law," Hadronic J. Supplement 13 (2), 191–202 (1998).
• Oleg D. Jefimenko, "The Trouton-Noble paradox," J. Phys. A. 32, 3755–3762 (1999).
• L. Nieves, M. Rodriguez, G. Spavieri, and E. Tonni, "An experiment of the Trouton-Noble type as a test of the differential form of Faraday's law," Il Nuovo Cimento 116 B (5), 585–592 (2001).

External links and online references

• Janssen, Michel (http://www.tc.umn.edu/~janss011/), "The Trouton Experiment and E = mc2 (http://www.tc.umn.edu/~janss011/pdf%20files/troutonshort.pdf)". (PDF)
• "Trouton Noble experiment (http://www.angelfire.com/scifi/EclipseLab/2k1/EG/TN.html)". (Less controlled experiment)
• "A Successful Trouton-Noble experiment (http://jnaudin.free.fr/html/troutnbl.htm)" (More controlled experiment)
• Cornille, Patrick, "On A Replication Of The Trouton-Noble Experiment (http://citeseer.nj.nec.com/cachedpage/404350/1)". Advanced Electromagnetic Systems. (More controlled experiment)
• Spavieri, Gianfranco, Miguel Rodríguez and Edgar Moreno, "Recent Developments in the Relativistic Electrodynamics Controversy (http://www.dipmat.unipg.it/~bartocci/ep6/ep6-spav.htm)".
• Mariwalla, K.H., and N.D. Hari Dass, "A Hundred Years of Larmor Formula (http://arxiv.org/abs/physics/0205046)". IMSC/98/01/03, Physics Education.
• Szames, Alexandre D., Patrick Cornille, Jean-Louis Naudin, and Christian Bizouard "Simple electrostatic aether drift sensors (SEADS): New dimensions in space weather and their possible consequences on passive field propulsion systems (http://content.aip.org/APCPCS/v504/i1/1004_1.html)". AIP Conference Proceedings Vol 504(1), January 19, 2000.
• Janssen, Michel: A Comparison between Lorentz's Ether Theory and Special Relativity in the Light of the Experiments of Trouton and Noble. 1995 (thesis) : Title/TOC (http://www.mpiwg-berlin.mpg.de/litserv/diss/janssen_diss/TitleTOC.pdf) - Intro (http://www.mpiwg-berlin.mpg.de/litserv/diss/janssen_diss/intro.pdf) - Intro (Part I) (http://www.mpiwg-berlin.mpg.de/litserv/diss/janssen_diss/introI.pdf) - Chapter 1 (http://www.mpiwg-berlin.mpg.de/litserv/diss/janssen_diss/Chapter1.pdf) - Chapter 2 (http://www.mpiwg-berlin.mpg.de/litserv/diss/janssen_diss/Chapter2.pdf) - Intro (Part 2) (http://www.mpiwg-berlin.mpg.de/litserv/diss/janssen_diss/introII.pdf) - Chapter 3 (http://www.mpiwg-berlin.mpg.de/litserv/diss/janssen_diss/Chapter3.pdf) - Chapter 4 (http://www.mpiwg-berlin.mpg.de/litserv/diss/janssen_diss/Chapter4.pdf) - References (http://www.mpiwg-berlin.mpg.de/litserv/diss/janssen_diss/References.pdf) (PDF)
• Bartocci, Umberto (http://www.dipmat.unipg.it/~bartocci/), "About the violations of the action-reaction principle in maxwell-lorentz electromagnetism, and the (im)possibility of electromagnetic "perpetual motion" machines (http://www.dipmat.unipg.it/~bartocci/koln.html)".