Measurements of general relativistic effects in the binary pulsar PSR1913 + 16, Nature 277, 8 February 1979, pp. 437-440 [FULL VOLUME]

FIRST EDITION OF THE FIRST DISCOVERY OF GRAVITATIONAL WAVES IN THE BINARY PULSAR - the gravitational waves Einstein predicted in his 1916 theory of general relativity. This is the first proof that "radiation leaves the system of a binary pulsar at exactly the speed of light and as gravitational waves" (Spotts, Einstein Verified, CSM, 11 Feb, 2016). While the discovery was considered indirect, it is also regarded as "the first proof [of] the existence of gravitational waves" or, put another way, the first proof that "radiation leaves the system of a binary pulsar at exactly the speed of light and as gravitational waves" (van Haasteren, Gravitational Wave Detection, 8; Spotts, Einstein Verified, CSM, 11 Feb, 2016). The Nobel Prize in Physics 1993 was awarded jointly to Russell A. Hulse and Joseph H. Taylor Jr. "for the discovery of a new type of pulsar, a discovery that has opened up new possibilities for the study of gravitation" (Nobel Prize Committee).

"Gravitational waves are ripples in spacetime that occur when an object moves with an accelerated motion that is not "spherically symmetric. The movement of the object causes the curvature of spacetime to change, causing gravitational waves to spread outward like a three dimensional analog of ripples on the surface of a pond" (History of Physics: The Wenner Collection).

"In 1975, Joseph Hooton Taylor, Jr. and Russell Alan Hulse discovered a pulsar (a highly magnetized rotating neutron star) in a binary star system with a dark companion, labeled PSR-1813+16.

Taylor, Fowler, and McCulloch then used the 1975 binary pulsar discovery to create highly precise tests of general relativity. The team tracked their binary pulsar over the following several years and as the two objects spiraled toward each other. In this paper, they announced that they had found a change in the orbital period of the double star - specifically, that the orbit of this binary system was slowly shrinking, or losing angular momentum, as it lost energy due to the emission of gravitational radiation. The reduction amounted to 75 millionths of a second per year and just equaled the predicted energy loss due to the radiation of gravitational waves" (ibid). This figure precisely equaled the rate of loss or shrinkage Einstein's theory of relativity predicted (ibid).

As Taylor et al. wrote: "Measurements of second- and third-order relativistic effects in the orbit of binary pulsar PSR1913 + 16 have yielded self-consistent estimates of the masses of the pulsar and its companion, quantitative confirmation of the existence of gravitational radiation at the level predicted by general relativity, and detection of geodetic precession of the pulsar spin axis" (Abstract).

Again, it is important to note that their discovery of gravitational radiation - and it was exactly that - was an indirect discovery. "No one had yet observed the direct action of gravitational waves on detectors" but in September of 2015, that day would come (Zeldovich, My Universe, 137). But as Zeldovich wrote of this paper, it is "in this way [that] gravitational radiation was discovered and gravitational astronomy began" (ibid). CONDITION & DETAILS: Full bound volume, 4to. (11 x 8 inches; 275 x 200mm). Ex-libris: Minor ghosting at spine from the removal of a spine label; three tiny marks on the rear pastedown. Tightly and solidly bound in red buckram; gilt-lettered at the spine. Clean and bright inside and out.