(Found) Anti war device that shifts away from a science based universe to one based on magic

[tenjen73]

Written in the 1980's(?) this is a story about a machine designed to alter the parameters of the universe in the event of a nuclear war. All science based devices become
inoperable. I think the book might have been stitched together from three shorter stories. I remember only a few details. When the change occurs munitions in the process of detonating become demons of various strength depending on the size of the weapon. Maybe there are two kinds of magic operating ( black and white) not sure.

 

[tachyon]

Sounds like Saberhagen's "Empire of the East" series. Prequel series to the Swords series. (Edit: by which I mean the subsequent Swords series is a sequel series to the Empire of the East books...)

 

[tenjen73]

Thank you. That sounds like the book I was thinking of.

 

[PaulMmn]

"The Genesis Machine" by James P Hogan has a computer interface that allows mental control of computers. Our Hero finds a nuclear 'switch' that can switch the universe into a state where nuclear power can only run 'slow' reactions; nuclear explosions are impossible. Our Hero switches the universe to that 'safe' state, and programs the computer to automatically switch it to that state should someone re-enable the more violent state. I don't think science-based devices are disabled.