くりこみ理論誕生のころ—一研究者の回想

摘要

Somehow or other, amid the ruin and turmoil or the war, totally isolated from the rest of the world, Tomonaga had maintained in Japan a school of research in theoretical physics that was in some respects ahead of anything existing anywhere else at that time. He had pushed on alone and laid the foundations of the new quantum electrodynamics, five years before Schwinger and without any help from the Columbia experiments. He had not, in 1943, completed the theory and developed, it as a practical tool. To Schwinger rightly belongs the credit for making the theory into a coherent mathematical structure. But Tomonaga had taken the first essential step. There he was, in the spring of 1948, sitting amid the ashes and rubble of Tokyo and sending us that pathetic little package. It came to us as a voice out of the deep.%前節終りに述べた問いに答えるために，理論研究者に見られる2つの型についての考察から始めたいと思う。以下ではそれぞれを'P型'，'F型'と呼ぶことにする。まずP型とは，実験データの分析から.現象の特徴を摑み，そこにある規則性を求め，そしてそれらを説明し得るような模型の可能性をも探索する，いゎゆる'現象論屋(phenomenologist)'のことである。物理的事実を直視することから出発するので'現実的(realistic)'であり，物理学の基礎を徐々に積み上げてゆくという意味で'上昇的'であり，そこから法則性を探るという点で，'具象的'•'帰納的'である。