Comment on Which is it Lemmy?
Bytemeister@lemmy.world 3 days agoHow is the portal affixed to the piston?
It’s doesn’t matter really, this is a red herring.
The box has to exit at the same rate it enters…
There is the problem with your logic. The box doesnt move, there is a shortcut in space that moves around it.
the law of conservation of mass and energy dictates that no new energy is created and it has to come from somewhere
EXACTLY!! A is the only scenario where energy (or more accurately, momentum) is conserved in this case. If you want to think about why that is, see my previous post where I extrapolated on a case where a lighter object with a portal on it is moved over the box.
if the portal was put on an object lighter than the box and then quickly moved over the box, the box would be launched at a speed equal to the speed of the lighter object, while it has more mass, this is not a conservation of momentum.
Duamerthrax@lemmy.world 3 days ago
This is not a red herring. A portal can be assumed to be massless and might not interact with anything. In theory, it could have infinite sharpness and cut though the piston when force is applied. But that’s not the hypothetical. The hypothetical has the portal fixed to the piston, interacting with mass. If it can interact with the piston, it can interact with
The box moves in relation to the portal opening. The reference frame is the portal opening. If, from start to finish, the box takes 1 second to enter the portal, it has to take one second to exit the portal. Everything works backwards from this. If traveling through the portal quickly would cause the box to be launched, then the energy has to come from somewhere and the piston is the only source.
Bytemeister@lemmy.world 3 days ago
Fine, let’s say it’s held on with elf cum. I’d love to see you explain how that matters.
Whoop, you made an incorrect assumption there. You are only using a frame of reference that includes the box and the portal, any conservation of momentum is only valid for that frame of reference.