11–19 of 19 posts
Doesn't this boil down to time-reversal? I doubt CPT symmetry is relevant here, so I'd be very surprised if it didn't simply reverse the rotation.
I've googled for about 5 minutes trying to understand ....is the "reverse sprinkler" just a device that has been impossible to build so it was a strictly theoretical problem? "We found that the reverse sprinkler spins in the ‘reverse’ or opposite direction when taking in water" - really, this was that impossible to build that nobody knew what it would do? weird
Plenty of people built one since Feynman stated the problem, it simply doesn't rotate or rotates very weekly on the same direction a normal sprinkler would. A lot of people think this is anti-intuitive.
Doesn't this boil down to time-reversal? I doubt CPT symmetry is relevant here, so I'd be very surprised if it didn't simply reverse the rotation.
Doesn't this boil down to time-reversal? I doubt CPT symmetry is relevant here, so I'd be very surprised if it didn't simply reverse the rotation.
I've googled for about 5 minutes trying to understand ....is the "reverse sprinkler" just a device that has been impossible to build so it was a strictly theoretical problem? "We found that the reverse sprinkler spins in the ‘reverse’ or opposite direction when taking in water" - really, this was that impossible to build that nobody knew what it would do? weird
Appling force to suck in water accelerates it and every action has an equal and opposite reaction
I do not get what the mystery is. What am I missing?
Doesn't this boil down to time-reversal? I doubt CPT symmetry is relevant here, so I'd be very surprised if it didn't simply reverse the rotation.
A normal sprinkler works by a pump pushing water out the nozzle. Wouldn't a time reversed sprinkler be a situation where water is flying into the sprinkler and depressing the pump? in that case I would expect the rotation to be reversed.
Wait. Is this meant to imply it’s running underwater?
Earlier quoted context omitted.
A normal sprinkler works by a pump pushing water out the nozzle. Wouldn't a time reversed sprinkler be a situation where water is flying into the sprinkler and depressing the pump? in that case I would expect the rotation to be reversed.
Well, yes. Isn’t that the situation the article is describing? Suction isn’t a real thing, so- Wait. Is this meant to imply it’s running underwater?
The article implies a situation where the pump is running in the opposite direction as normal, sucking the water in. That's not time-reversed though (eg in the time reversed version, the pump generates electricity instead of consuming it, because the water is pushing it instead of it pushing the water)