As tensors are the language of general relativity, Schild wrote Tensor Calculus with John L. Synge as a textbook.[2] According to a reviewer, "The ideas and concepts are given very concisely and thus a wide range of subjects is considered."[3]
In 1962 Alfred got me an associate professorship in the Austin mathematics department, and in the summer of 1962, while attending Andrzej Trautman’s Relativity conference in Warsaw, Poland, … we persuaded Roger Penrose, Roy Kerr, Ray Sachs, Jürgen Ehlers, Luis Bel and others to flock to the newly created center of gravity in Austin.[5]
In 1965, Schild found the Kerr–Schild form of the spacetime metric.
A dramatization of the calculation of the Kerr metric by Roy Kerr was written in 2009 by Fulvio Melia.[6] Kerr had invited Schild to his office to calculate angular momentum in a solution to Einstein's field equations. "Alfred was a kind and cheerful man, with a flock of silvery hair."[6]: 74 The climax of Cracking the Einstein Code was expressed as follows:
While Schild waited patiently in the armchair, Kerr began calculating at his desk...Kerr put down his pencil and looked up...Schild jumped out of his chair beaming. He appeared to be far more excited than Kerr himself and clearly knew what this meant.[6]: 75
Schild clarified and enlarged general relativity through his studies of single-particle motion, quantization, special solutions and the conformal structure of space-time. ... His expositions of tensor analysis and relativity are still among the best and clearest treatments of these subjects.[7]
Oren, Amanda. "SCHILD, ALFRED". Handbook of Texas On-Line. Retrieved 7 August 2005.
Debney, G.C.; Kerr, R. P. & Schild, A. (1969). "Solutions of the Einstein and Einstein-Maxwell Equations". J. Math. Phys. 10 (10): 1842. Bibcode:1969JMP....10.1842D. doi:10.1063/1.1664769.