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Collapse of Quantum Wavefunction Captured In Slow Motion
ananyo writes "It is the most fundamental, and yet also the strangest postulate of the theory of quantum mechanics: the idea that a quantum system will catastrophically collapse from a blend of several possible quantum states to just one the moment it is measured by an experimentalist. Researchers have now been able to capture that collapse through the use of weak measurements — indirect probes of quantum systems that tweak a wavefunction slightly while providing partial information about its state, avoiding a sudden collapse. Atomic and solid-state physicist Kater Murch of the University of California, Berkeley, and his colleagues performed a series of weak measurements on a superconducting circuit that was in a superposition — a combination of two quantum states. They did this by monitoring microwaves that had passed through a box containing the circuit, based on the fact that the circuit's electrical oscillations alter the state of the microwaves as they pass through the box. Over a couple of microseconds, those weak measurements captured snapshots of the state of the circuit as it gradually changed from a superposition to just one of the states within that superposition — as if charting the collapse of a quantum wavefunction in slow motion."
"Catastrophically collapse", really? What's catastrophic about it?
Generally speaking, when it collapses, it involves destroying a nearly infinite number of possibilities in an absolutely irreversible way. The collapse is complete.
Its pretty much the definition of catastrophic.
That said, its a bit of hyperbole that probably wasn't needed. But its not inaccurate.
Did you really expect to see a video of a quantum wavefunction?
I did and I didn't.
±5 Funny
the 'conciousness' part of Copenhagen is an anthropic bias
It's worse than that. According to defenders of the Many-Worlds interpretation (of which I consider myself one), Copenhagen's collapse has several problems. Less Wrong's Eliezer Yudkowsky has written an extensive introduction to QM from the perspective of the Many-Worlds Interpretation and as part of the series he's extensively criticized the collapse postulate, summarizing its problems thus:
Given the above considerations, whatever the experiment detected is most certainly not collapse.
Conservatism: (n.) love of the existing evils. Liberalism: (n.) desire to substitute new evils for the existing ones.
What did you expect a video of, exactly?
Well, I was expecting a slow motion video of the collapse of a quantum wavefunction, myself.
When our name is on the back of your car, we're behind you all the way!
http://www.youtube.com/watch?v=-fSqFWcb4rE
They have a video camera that takes frames faster than light can travel, so they have the technology. Problem is it requires the subject to be ungodly bright.
No. No they don't. They have a "camera" with a very fast shutter speed. Then they take millions of pictures of different laser pulses and stitch them together to create an animation that mimics a single laser pulse.
I know that the comments on youtube are pretty poor and that most people rarely read articles but this is a really cool video and if you can't be bothered to understand what you're looking at then I feel sorry for you.