Gustav Adolf Ising (19.02.1883-5.02.1960) was a Swedish physicist and geophysicist and a member of the Royal Swedish Academy of Sciences (1935). He graduated from the university in Uppsala (1903) and the Royal Institute of Technology in Stockholm (1910). In 1920-28 he worked at Stockholm University, and from 1934 he was professor at the Royal Institute of Technology.
His research was in the field of electromagnetism, gravimetry and accelerator technology. In 1925 he proposed a linear resonance accelerator and put forward the two basic ideas of the indirect methods of acceleration: the repeated use of one and the same small potential difference, and synchronism (resonance) between the arrival of the particle and that of the accelerating field at one and the same place. He designed a sensitive electrometer and a number of galvanometers and gravimeters.