Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

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

quantamagazine.org

Post reply on HN
Print view View original

1–10 of 49 posts

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

#2

Post by xhkkffbf »

I'm certainly interested in this, but for different reasons. Over the years, several people have bent my ears about Duane's theorem that suggests the double-slit experiment is not demonstrating quantum effects at all.

It strikes me that this could help establish or overturn such claims.

https://billwadge.wordpress.com/2019/10/25/double-slit-exper...

Any thoughts? Could it help to test it on a planet-sized scale?

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

#3

Post by oogabooga123 »

xhkkffbf wrote: post #2

I'm certainly interested in this, but for different reasons. Over the years, several people have bent my ears about Duane's theorem that suggests the double-slit experiment is not demonstrating quantum effects at all. It strikes me that this could help establish or overturn such claims. https://billwadge.wordpress.com/2019/10/25/double-slit-exper... Any thoughts? Could it help to test it on a planet-sized scale?

Seems like this hypothesis shows it is indeed demonstrating “quantum” effects because the math falls out of the quantization of momentum transfer. Of course “quantum” is now widely understood to mean “the weird phenomena like the double slit experiment”... but I get what you’re saying. I wonder what’s with the downvote, though.

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

#4

Post by Moodles »

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, know what "feels" like the best move in Chess or something, without really being able to articulate why. That kind of intuitive feel for how something works usually leads to concrete logical understanding later on.

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

#6

Post by selimthegrim »

xhkkffbf wrote: post #2

I'm certainly interested in this, but for different reasons. Over the years, several people have bent my ears about Duane's theorem that suggests the double-slit experiment is not demonstrating quantum effects at all. It strikes me that this could help establish or overturn such claims. https://billwadge.wordpress.com/2019/10/25/double-slit-exper... Any thoughts? Could it help to test it on a planet-sized scale?

I would think Abraham-Minkowski problem would make people wary about defining rules for momentum exchange with solid systems.

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

#8

Post by andi999 »

dukeofdoom wrote: post #5

You can simulate quantum effects with just polarized glasses. https://www.youtube.com/watch?v=zcqZHYo7ONs

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.

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

#10

Post by lisper »

Moodles wrote: 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. Most "quantum weirdness" is simply a result of confusing them.

It is also important to understand that the reason these things are often conflated is that much of what is (or at least used to be before quantum computation became a thing) taught as quantum mechanics focuses on the special case of a single particle considered in isolation. In that one special case -- and ONLY in that one special case -- configuration space is the same as (or at least isomorphic to) physical space. But as soon as you add a second particle, that stops being true.

So the key to understanding QM is to START with the multi-particle case. This is actually easier than the single particle case because it forces you to set aside a lot of the things that make quantum mechanics difficult in general and focus on the thing that makes it hard to wrap your brain around: entanglement. But the reason that entanglement is hard to wrap your brain around is that it's weird when considered from the point of view of physical space. If you start with multi-particle systems, that forces you to start with configuration space, and that gets you past the hard part right from the start. After that it's just math.

Post reply on HN