Horace Heffner wrote: > > On Feb 1, 2006, at 10:20 AM, Harry Veeder wrote: > > >> Could Gravimagnetism be involved in the precession of the perihelion >> of planet mercury? >> >> http://phyun5.ucr.edu/~wudka/Physics7/Notes_www/node98.html >> >> Harry >> > > > Gravimagnetism has much to do with the precession of non-circular > obits. Gravimagnetism embodies the relativistic effects due to > retardation. It does not account for red shift due to gravitational > or acceleration time dilation. Jefimenko noted that the entire rate > of precession of Mercury's perihelion could be accounted for by > merely reducing the speed of gravity to less than c. Since the time > he wrote his book, however, the speed of gravity has been measured at > c. (See: http://news.bbc.co.uk/2/hi/science/nature/2639043.stm) > This implies Einstein's explanation of the remaining bit of > precession is still necessary. > > The reason gravimagnetism plays a strong role in orbit precession is > that it is a 1/r^3 effect. The attraction and thus acceleration close > up to the sun is greater than further out. The angular motion of > mercury is increased a little bit when up close to the sun, and thus > the precession of the orbit results. > > Horace Heffner >
Presumably then gravimagnetism is not required to explain _any_ of the orbital precession since it can all be explained by classical and relativistic physics. Harry
