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Quantum Double-Slit Experiment Offers Hope for Earth-Size Telescope

quantamagazine.org

31–40 of 49 posts

Re: Quantum Double-Slit Experiment Offers Hope for Earth-Size Telescope

#31
post #28
post #17

Earlier quoted context omitted.

"Configuration space" means that the state of the world is described by some list of numbers that don't actually correspond directly to locations in space or time. Or even mass or energy. It means that those things aren't really fundamental. What's fundamental is some other set of things that aren't too difficult to work with mathematically, but which don't correspond exactly to anything you're familiar with. The bes…

> means that the state of the world is described by some list of numbers How is that different from hidden variables?

Yeah I'm honestly not too sure here either, the more I think the more I believe simulation + hidden variables may be the true explanation behind our reality.

Re: Quantum Double-Slit Experiment Offers Hope for Earth-Size Telescope

#32
post #29
post #17

Earlier quoted context omitted.

"Configuration space" means that the state of the world is described by some list of numbers that don't actually correspond directly to locations in space or time. Or even mass or energy. It means that those things aren't really fundamental. What's fundamental is some other set of things that aren't too difficult to work with mathematically, but which don't correspond exactly to anything you're familiar with. The bes…

where & how is the 'configuration' encoded? [we don't know, right] Is this why string theory requires higher dimensions? Also when I see the term 'harmonic oscillations', I think of plucking a string -- it seems so elegant for the physical particles to be manifestations of higher dimensional ~~vibrating~~ oscillating strings :) (thinking of flat-lander analogy) gp's premise about learning with the multi-particle land…

https://en.wikipedia.org/wiki/Holographic_principle

Re: Quantum Double-Slit Experiment Offers Hope for Earth-Size Telescope

#33

Could this method be used to image exoplanets or is that still in the theoretical realm of the Solar gravitational lens[1]? [1]: https://en.wikipedia.org/wiki/Solar_gravitational_lens

I believe this would be able to provide at least low resolution images of earth-sized exoplanets.

Low resolution as in 16x16, or 320x320?

And what of closer objects?

Would we be able to directly image the Apollo-landing sites for instance?

Re: Quantum Double-Slit Experiment Offers Hope for Earth-Size Telescope

#34
post #29
post #17

Earlier quoted context omitted.

"Configuration space" means that the state of the world is described by some list of numbers that don't actually correspond directly to locations in space or time. Or even mass or energy. It means that those things aren't really fundamental. What's fundamental is some other set of things that aren't too difficult to work with mathematically, but which don't correspond exactly to anything you're familiar with. The bes…

where & how is the 'configuration' encoded? [we don't know, right] Is this why string theory requires higher dimensions? Also when I see the term 'harmonic oscillations', I think of plucking a string -- it seems so elegant for the physical particles to be manifestations of higher dimensional ~~vibrating~~ oscillating strings :) (thinking of flat-lander analogy) gp's premise about learning with the multi-particle land…

> we don't know, right

Right.

> Is this why string theory requires higher dimensions?

No. The higher dimensions of string theory are actual physical dimensions. Configuration space dimensions are pure mathematical abstractions, and there are potentially an infinite number of them, one for every degree of freedom in the system. Look up "Hilbert space" if you want the gory details.

Re: Quantum Double-Slit Experiment Offers Hope for Earth-Size Telescope

#35
post #10
post #4

That animation at the top of the article of the possible locations of the photon is very cool. Quantum behavior seems so counterintuitive to us because we're just apes who evolved minds to survive in the macroscopic world of the African savanna. But I wonder if we perhaps taught quantum behavior to kids from an early age, whether they could get an intuitive understanding for it, in the the same way that I can, like,…

It's actually not that hard to get an intuitive understanding of QM even as an adult. The key is having the right pedagogy, which is very rare. IMHO the key to the right pedagogy is just one crucial insight: the wave function lives in configuration space , not in physical space. How physical space emerges from configuration space is a deep mystery. No one knows. But it is CRUCIAL not to conflate these two things. Mos…

You are right that realizing that the wavefunction lives in configuration space is a big leap that is hard for people, but there is another leap which is more difficult IMO. It is that quantum probability amplitudes are not like classical probabilities: they have phases and can interfere with each other in ways that classical probabilities do not. This explains the weird interference patterns in the cool animation in the article. In my experience, understanding the idea of a distribution over configuration space isn't so hard. But getting an intuitive grasp of the behavior of probability amplitudes that can interfere with each other is hard.

Re: Quantum Double-Slit Experiment Offers Hope for Earth-Size Telescope

#36
post #8

Earlier quoted context omitted.

You can't. This is just covered by classical electrodynamics. Of course in a sense you can say anything is quantum, but then the stability of a table is quantum (which it is). If you were to have a single photon source and avalanche detector, ok now you are talking quantum.

The first 2 minutes of that video make it clear that they think it is "real" quantum effects (e.g. at 1:34 entanglement > EPR paradox > Bell's Theorem > local realism). Those are pretty quantum-y imo.

Yeah. At 9:34 they're dealing with entangled photons passing through 2 filters at different points in space, simultaneously. They affect each other, which is impossible without faster-than-light communication between them. This is absolutely quantum and cannot be explained at all by classical EM.

Re: Quantum Double-Slit Experiment Offers Hope for Earth-Size Telescope

#40
post #34
post #29

Earlier quoted context omitted.

where & how is the 'configuration' encoded? [we don't know, right] Is this why string theory requires higher dimensions? Also when I see the term 'harmonic oscillations', I think of plucking a string -- it seems so elegant for the physical particles to be manifestations of higher dimensional ~~vibrating~~ oscillating strings :) (thinking of flat-lander analogy) gp's premise about learning with the multi-particle land…

> we don't know, right Right. > Is this why string theory requires higher dimensions? No. The higher dimensions of string theory are actual physical dimensions. Configuration space dimensions are pure mathematical abstractions, and there are potentially an infinite number of them, one for every degree of freedom in the system. Look up "Hilbert space" if you want the gory details.

thanks
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