Stan Ulam and Edward Teller invented the approach to making an thermonuclear bomb that turned out to work. Ulam's idea was using the hydrodynamic shock produced by a fission bomb to compress the fusion materials. Teller improved that idea by using the radiation pressure (rather than hydrodynamic pressure) to do the compression. Teller, who had been the tireless advocate of the H-bomb and spent many years on an idea that didn't work, didn't want to share credit.
Edward Teller seems to have found it intolerable that someone might share credit for the historic invention on which he had been working single-mindedly for almost ten years; he moved immediately to take over the technical breakthrough and make it his own. After he and Ulam issued their joint report, Françoise Ulam observes, “my impression is that from then on Teller pushed Stan aside and refused to deal with him any longer. He never met or talked with Stan meaningfully ever again. Stan was, I felt, more wounded than he knew by this unfriendly reception, although I never heard him express ill feelings toward Teller. (He rather pitied him instead.) Secure in his own mind that his input had been useful, he withdrew.”2187 (Carson Mark confirms Françoise Ulam’s impression: “Ulam felt that he invented the new approach to the hydrogen bomb. Teller didn’t wish to recognize that. He couldn’t bring himself to recognize it. He’s taken occasion, almost every occasion he could, not every one, to deny that Ulam contributed anything. I think I know exactly what happened in the interaction of those two.2188 Edward would violently disagree with what I would say. It would be much closer to Ulam’s view of how it happened.”)
Rhodes, Richard. Dark Sun: The Making Of The Hydrogen Bomb (p. 471). Simon & Schuster. Kindle Edition.
More ammo for the Teller was a giant jerk view of history.