
Quantum Interference Between Light Sources Separated by 150M Kilometers - wwarner
https://journals.aps.org/prl/abstract/10.1103/PhysRevLett.123.080401
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nayuki
150 million kilometers = 150 gigameters

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rolltiide
that helped

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Zenst
"The experiment can be further extended to a larger scale using photons from
distant stars and open a new route to quantum optics experiments at an
astronomical scale."

This would be interesting as a distant star would exhibit red-shift unlike
something as close as our sun. So until further data such as this, we just
have the single experiment. Which from my limited understanding, would give
the data to draw some solid conclusions. Exciting stuff, and I could only
speculate upon the results, though somebody more up upon the matter may well
have some better insights.

Though it may well be a way to measure distances more accurately would be my
limited take away from this. Maybe not, but certainly something going on here
that will enhance our understanding of physics on all levels.

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wwarner
An ars-technica writeup of the original paper:
[https://arstechnica.com/science/2019/08/identical-photons-
ge...](https://arstechnica.com/science/2019/08/identical-photons-
generated-150-million-kilometers-apart/)

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wwarner
pdf of paper
[https://arxiv.org/pdf/1905.02868](https://arxiv.org/pdf/1905.02868)

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isostatic
Ok, does anyone have a simple guide to what it means?

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bmcooley
I have a limited understanding, but I think this is just further reproduction
of the same science. I believe there's some controversy over non-locality in
that entanglement and spooky action at a distance is still a result of hidden
local variables. By increasing the distance between the sources of the
photons, you would give more evidence to nonlocality. Please correct me if
this is offbase.

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longtom
Non-locality means that the way the probability of presence (wave function) of
a photon is determined is by trying out all possible paths through the entire
universe at once rather than only in regions nearby the photons?

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Misdicorl
The path integral formulation is the most prevalent and successful version of
quantum physics (this is what you describe in the second half). Non locality
is different; it supposes that there are hidden mechanisms we have not
uncovered (and may but be able to uncover) instead which describes our world.
It must be non local to get the observed experimental results. Non local means
data about the universe is teleporting faster than (conventional) causality
allows i.e. the speed of light

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longtom
Either case seems to require faster-than-light or instant communication
between alternative paths that are being tried out, so the distinction is
whether the combination of different paths is mediated by another faster-than-
light (non-local) particle or whether the combination is axiomatic to the laws
of the universe without a particle mediating it?

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Misdicorl
No, the path integral formulation does not require faster than light
communication. Time is an explicit parameter

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dboreham
A bug in the simulator?

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Zenst
This wasn't a simulation, unless your going down the universe is a simulation
avenue and this is a bug in the matrix route.

