Pynchon uses Maxwell's Demon to synthesize the fields of thermodynamics and information theory together into a mysterious unity. The later area obtained the technical term "entropy" as a metaphor borrowed from its classical origin in thermodynamics. John Nefastis, owner of a Demon Box, explains the joining of disciplines to Oedipa: "Entropy is a figure of speech, then, a metaphor. It connects the world of thermodynamics to the world of information flow. The machine uses both. The Demon makes the metaphor not only verbally graceful, but objectively true" (106). Nefastis makes a grand cabalistic connection between heat engines and communication with the striking similarity of the respective mathematical representations of these two areas: "The equation for one, back in the '30's, had looked very like the equation for the other. It was a coincidence" (105). He regards this chance similarity and its relation to his Machine as a great nexus: "'The two fields were entirely unconnected, except at one point: Maxwell's Demon'" (105; curiously, the actual equations Pynchon is referring to here are somewhat of a mystery, because Claude Shannon's famous information-entropy equations were not published until 1948). With this mathematical insight, Nefastis is developed as another of Pynchon's paranoiacs; apparently "The word [entropy] bothered him as much as 'Trystero' bothered Oedipa" (ibid., 105).
Pynchon proposes a revolutionary spiritual link to operate Nefastis' original style Maxwell's Demon box. The Demon in the box must engage in a cycling of information with a person who has "the gift" -- a "sensitive" who acts as an intermediary in the process of sorting (87). Nephastis explains: "There are untold billions of molecules in that box. The Demon collects data on each and every one. At some deep psychic level he must get through. The sensitive must receive that staggering set of energies. . ." (105). The Demon dumps the waste of billions of deleted memories on the person outside the box and thus purges entropy. The Machine has a piston above each of the two cylinders (analogous to the "Rooms" in the discussion above), and as the Demon works off of a continuos feedback loop with the sensitive, one of these pistons will rise as a result of the sorting of the molecules. The cylinder containing the higher energy molecules will rise in temperature and pressure, thus raising the piston as an indication of success.
Oedipa later reflects back on the "massive destructions of information" essential to the Nefastis machine, and discovers this "irreversible process" of erasure herself (128). She conceives of the destruction of memory in the recycled bed of an old dying alcoholic sailor: "So when this mattress flared up around the sailor, in his Viking's funeral: the stored, coded years of uselessness, early death, self-harrowing, the sure decay of hope, the set of all men who had slept on it, whatever their lives had been, would truly cease to be, forever, when the mattress burned" (128). This irreversible destruction of memory, emerges again as Oedipa considers that the Tristero could be Pierce Inverarity's attempt to escape erasure: "he might even have tried to survive death, as a paranoia; as a pure conspiracy against someone he loved" (179). Perhaps, the entire story of COL 49 is the struggling memory (if Pierce indeed left this great conspiracy to torment Oedipa) of a dead man, desperate to endure annihilation.
Nefastis brings his Machine out to Oedipa, and there on top of the box, she sees a picture of J.C. Maxwell himself (as in the above picture from: Thompson, J.J. et al. James Clerk Maxwell; A Commemorative Volume Cambridge: Cambridge UP, 1931). He gives instruction to watch the picture, focus her concentration on one of the cylinders and leave her mind open:
She looked at the picture on the outside of the box. Clerk Maxwell was in profile and would not meet her eyes. The forehead was round and smooth, and there was a curios bump at the back of his head, covered by curling hair. His visible eye seemed mild and noncommittal, but Oedipa wondered what hangups, crises, spookings in the middle of the night might be developed from the shadowed subtleties of his mouth, hidden under a full beard. (106)This passage with Maxwell's Demon is indicative of Pynchon's fascination with the esoteric and bizarre facets of science based mysticism. In COL 49 and also in Gravity's Rainbow with such manifestations as the "White Visitation," Pynchon investigates the occurrence of the occult and its relation to scientific explanations of reality. Maxwell's Demon is traditionally a conception that attempts to blur the clear defining laws of physics. Pynchon adds the use of "sensitives" to work his version of this perpetual engine, and successfully realizes an unusual synthesis of psychic powers and science.
With Oedipa and the box, eventually nothing happens. The reader is left without witnessing the Machine in action. Oedipa appears not to be a sensitive. She cannot destroy memory for the Demon. Ultimately, she cannot escape her memory of the dead either. She continues on, obsessed by the trail of Inverarity and the Tristero, desperately hoping for an epiphany at the Crying of Lot 49.