There are perfectly consistent models of a relativistic universe with well-defined rules that allow tachyons (particles that travel faster than light). Frank Arntzenius has a great paper on this. These models don’t allow “future-changing” time travel, though.
Incidentally, does anyone know of a work of fantasy that has clearly articulating “law-like” constraints governing the use of magic? The awesome webcomic Unsounded seems to be attempting something like this, but the details are still fuzzy.
Most works of fantasy do this to some extent. For example, the One Power in Wheel of Time has very well-specified mechanics, though of course a lot of the complexity is left as an exercise for the reader. The metal-based magic in the Mistborn books is simpler, and likewise well-defined. You can also have works like Cardcaptor Sakura, which is basically an anime about a collectible card game; here, the cards operate according to some very specific rules, and each card has a narrow function, but the card list is very large and fairly arbitrary.
Interesting. That paper is behind a paywall, unfortunately.
But my knowledge of physics is very limited and I probably wouldn’t understand the full paper anyway. (What tachyon interactions with non-tachyons does he allow?) I doubt, though, that any model of tachyons allows you to accelerate your normal-matter spaceship to FTL speeds the way most soft scifi takes for granted.
There are perfectly consistent models of a relativistic universe with well-defined rules that allow tachyons (particles that travel faster than light). Frank Arntzenius has a great paper on this. These models don’t allow “future-changing” time travel, though.
Incidentally, does anyone know of a work of fantasy that has clearly articulating “law-like” constraints governing the use of magic? The awesome webcomic Unsounded seems to be attempting something like this, but the details are still fuzzy.
Most works of fantasy do this to some extent. For example, the One Power in Wheel of Time has very well-specified mechanics, though of course a lot of the complexity is left as an exercise for the reader. The metal-based magic in the Mistborn books is simpler, and likewise well-defined. You can also have works like Cardcaptor Sakura, which is basically an anime about a collectible card game; here, the cards operate according to some very specific rules, and each card has a narrow function, but the card list is very large and fairly arbitrary.
Interesting. That paper is behind a paywall, unfortunately.
But my knowledge of physics is very limited and I probably wouldn’t understand the full paper anyway. (What tachyon interactions with non-tachyons does he allow?) I doubt, though, that any model of tachyons allows you to accelerate your normal-matter spaceship to FTL speeds the way most soft scifi takes for granted.