An Involuntary Movement

An invisible energy field that the espers involuntarily produce. One example of this is when Tōma finds Misaka Mikoto by following wind turbines that are turning without wind. Mikoto's body involuntarily produces voltage all the time; thus Tōma comes to the conclusion that it can power the wind turbines. Another is the Accelerator's "default" setting to automatically deflect any energy or matter that approaches him.

A entity from the combined AIM of the city's residents, Kazakiri Hyouka, was made by Aleister for the purpose of controlling the Imaginary Number Sector. She normally exists in a shadow dimension, the city of shimmers (which is also the true 'Imaginary Number Sector' - most magicians think Imaginary Number Sector refers to Aleister's windowless building), unable to interact with people, but altering anything that attracts her attention. She can temporarily manifest in the real world as an immortal entity at times, once by contact with Index and another time by inputting a certain code into Last Order. When she's manifested any damage she takes, even to her clothing, is repaired in a few minutes. The novels (specifically volume 6) themselves state that should Kazakiri comes into direct contact with Imagine Breaker she would be erased, since even if she's alive she's made of the AIM dispersion field, and as Imagine Breaker wipes out supernatural effects regardless of it being good or evil she is no exception.

It is also shown that there are several different manifestations of ones AIM, and that an sufficiently powerful esper can evolve and gain control of their AIM (awakening), and update the very laws of reality themselves. AIM is toxic to mages, and is also shown to have anti-magic capabilities in sufficient amounts.

The AIM Dispersion Field has been a main focus in most stories on the Science Side, with examples such as the AIM Burst, Kazakiri Hyouka, and Artificial Heaven.