The corn-syrup/sugar example is interesting, but I think the analogy doesn’t work. Bottom line: Male-female copulation is a biological necessity. Sugar in white-granule form is not. Biological instinct cannot be easily high-jacked. Sugar can. So, although Zach’s probably right there are real cultural changes afoot, I don’t think tentacles or what have you pose any real threat to the desire of young adolescents for the hot ladies in the tribe.

http://www.thestranger.com/seattle/SavageLove?oid=1192438

Just to belabor the point: I suspect the mechanism is something like whatever stimulus is present while a young adolescent (maybe earlier) is horny becomes the trigger after repeated exposure. Historically that’s been all the hot ladies in the tribe. Now it’s tentacle porn.

Can millennia of biology really be thwarted so easily?

Another thought — I’m not convinced that reported sexual dissatisfaction is caused by the weirdness of internet porn. There are lots of reasons why the people in that study might not be satisfied. It’s definitely not clear what the cultural consequences of this are, you’re right about that. But how clear is it that those consequences will be negative?

Here’s an apparent truism: if an event is possible at all, then it should also be possible if every event in the universe were translated forward in time by 1 second. That’s called time translation symmetry. But a shocking theorem by Emmy Noether proves that if this is true, then there’s a conserved quantity that (in everday circumstances) is exactly energy. So, local energy conservation is actually built into the symmetries of the Universe.

Two hesitations.

First, this only rules out perpetual motion of the first kind. Perpetual motion of the second kind is not strictly impossible, just very unlikely (by the 2nd law of thermodynamics). And perpetual motion of the third kind remains both possible and viable! (I assume the rolling ball video is something close to that.)

Second, even perpetual motion of the first kind is possible on a large scale, where time-translation symmetry fails. For example: in standard big-bang models of cosmology, the Universe is expanding, while the total amount of matter-energy remains fixed. Obviously, this implies energy density is decreasing. And if the Universe were on its way to a big crunch, then total energy would be increasing — giving us energy “for free.” Maybe all those smart, crazy people were onto something….