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In general relativity, Lense–Thirring precession or the Lense–Thirring effect is a relativistic correction to the precession of a gyroscope near a large rotating mass such as the Earth. It is a gravitomagnetic frame-dragging effect. It is a prediction of general relativity consisting of secular precessions of the longitude of the ascending node and the argument of pericenter of a test particle freely orbiting a central spinning mass endowed with angular momentum .
In celestial mechanics, apsidal precession is the precession of the line connecting the apsides of an astronomical body's orbit. The apsides are the orbital points farthest (apoapsis) and closest (periapsis) from its primary body. The apsidal precession is the first time derivative of the argument of periapsis, one of the six main orbital elements of an orbit. Apsidal precession is considered positive when the orbit's axis rotates in the same direction as the orbital motion. An apsidal period is the time interval required for an orbit to precess through 360°, which takes Earth's orbit about 112,000 years, completing a cycle and returning to the same orientation.
Gravitoelectromagnetism, abbreviated GEM, refers to a set of formal analogies between the equations for electromagnetism and relativistic gravitation; specifically: between Maxwell's field equations and an approximation, valid under certain conditions, to the Einstein field equations for general relativity. Gravitomagnetism is a widely used term referring specifically to the kinetic effects of gravity, in analogy to the magnetic effects of moving electric charge. The most common version of GEM is valid only far from isolated sources, and for slowly moving test particles.
Frame-dragging is an effect on spacetime, predicted by Albert Einstein's general theory of relativity, that is due to non-static stationary distributions of mass–energy. A stationary field is one that is in a steady state, but the masses causing that field may be non-static — rotating, for instance. More generally, the subject that deals with the effects caused by mass–energy currents is known as gravitoelectromagnetism, which is analogous to the magnetism of classical electromagnetism.
Ignazio Ciufolini is an Italian physicist active in the field of gravitational physics and general relativity.
Lorenzo Iorio, born in Bari in, is an Italian physicist working in general relativity, gravitation and related topics in astronomy and astrophysics.
References
- ↑ "Neil Ashby | Class of 1951".
- ↑ "Ashby, Neil". Archived from the original on 2016-03-03.
- ↑ "Canonical planetary perturbation equations for velocity-dependent forces, and the Lense-Thirring precession".
- ↑ Turyshev, Slava G; Anderson, John D; Hellings, Ronald W (1996). "Relativistic Gravity Theory And Related Tests With A Mercury Orbiter Mission". arXiv: gr-qc/9606028 .
- ↑ Ashby, N. (August 1994). "Relativity in the future of engineering". IEEE Transactions on Instrumentation and Measurement. 43 (4): 505–514. Bibcode:1994ITIM...43..505A. doi:10.1109/19.310159.
- ↑ Introduction to Relativistic Effects in the Global Positioning System
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