Einstein first predicted the existence of gravitational waves in 1916. He returned to the problem 20 years later, working with his assistant, Rosen. Einstein and Rosen thought that they had found a proof for the non-existence of gravitational waves.[2] But an anonymous reviewer—posthumously revealed to beHoward Percy Robertson—pointed out their misunderstanding of the coordinates they were using.[3] Einstein and Rosen resolved this issue and reached the opposite conclusion, exhibiting the first exact solution to field equations of general relativity describing gravitational waves.[2][3]
This metric can be written in a form such that theBelinski–Zakharov transform applies, and thus has the form of agravitational soliton. In 1972 and 1973, J. R. Rao, A. R. Roy, and R. N. Tiwari published a class of exact solutions involving the Einstein–Rosen metric.[4][5][6] In 2021 Robert F. Penna found an algebraic derivation of the Einstein–Rosen metric, using theGeroch group.[7]
in which the integrability of the function is guaranteed. A simple separable solution is given by
where is a constant, is the frequency and is theBessel function. For Einstein–Rosen waves, theC-energy, defined to be,[8] is not constant in time and oscillates periodically.
In the general case, one can write
Suppose, i.e., is given by the cosine series, then we have[8]
^abWill, Clifford (2016). "Did Einstein Get It Right? A Centennial Assessment".Proceedings of the American Philosophical Society.161 (1):18–30.JSTOR45211536.
^Rao, J.R.; Roy, A.R.; Tiwari, R.N. (1972). "A class of exact solutions for coupled electromagnetic and scalar fields for einstein-rosen metric. I".Annals of Physics.69 (2):473–486.Bibcode:1972AnPhy..69..473R.doi:10.1016/0003-4916(72)90187-X.
^Rao, J.R; Tiwari, R.N; Roy, A.R (1973). "A class of exact solutions for coupled electromagnetic and scalar fields for Einstein-Rosen metric. Part IA".Annals of Physics.78 (2):553–560.Bibcode:1973AnPhy..78..553R.doi:10.1016/0003-4916(73)90272-8.
^Roy, A.R; Rao, J.R; Tiwari, R.N (1973). "A class of exact solutions for coupled electromagnetic and scalar fields for einstein-rosen metric. II".Annals of Physics.79 (1):276–283.Bibcode:1973AnPhy..79..276R.doi:10.1016/0003-4916(73)90293-5.
^abcChandrasekhar, S. (1986). Cylindrical waves in general relativity. Proceedings of the Royal Society of London. A. Mathematical and Physical Sciences, 408(1835), 209-232.