Quantum swing – a pendulum that moves forward and backwards at the same time

[jonbaer]

http://phys.org/news/2016-05-quantum-swinga-pendulum.html

[basicplus2]

sounds more like it is moving backwards and forwards in time...

[golergka]

Wait, I'm stupid. Does the graphic mean that the atoms begin "vibrating" before they get the "kick"?

[Florin_Andrei → golergka]

"Before" and "after" have sharp, non-fuzzy edges only on the macro level.

[golergka → Florin_Andrei]

I don't quite understand how causality can be fuzzy. Can they detect the reaction before they decide to take action and decide not to take it based on this detection?

[coldtea → golergka]

Causality is not really applicable...

[slashdev → coldtea]

Please somebody elaborate on this - it's not an easy concept for a layperson to grasp.

[ubercore → slashdev]

I'll take a stab, but I'm basically a layperson as well, so take this with a grain of salt.

Causality would be tough to apply I think because of the quantum nature of the interaction. The object initiating the motion is quantum as well, so it's tough to say precisely when it should interact. So it's not as if the object is "anticipating" the interaction, it's that the quantum field already is interacting before our classical intuition of a non-quantum particle would say it is.

At least, I think :)

[coldcode]

Galileo is spinning in his grave - both ways.

[neals → coldcode]

And he's both dead and alive in there!

[seangrogg → neals]

I just opened the box. He's dead.

[at-fates-hands → neals]

Galileo had a cat?

[ArkyBeagle → coldcode]

All four ways. Er, eight. Maybe 16....