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> physicists are debating what it would really prove. Well, if we can detect the graviton before we have a working quantum theory of gravity, it would mean tha

> physicists are debating what it would really prove. Well, if we can detect the graviton before we have a working quantum theory of gravity, it would mean that gravity is in fact quantized and that we just need to figure it out. This would be a very big deal.

toomuchtodo 2y ago
> This would be a very big deal. Gravity drive?
- cryptonector 2y ago
  Nope.
itishappy 2y ago
They can detect an interaction, but they can't prove that it's quantized without (I believe) sub-Poissonian statistics[0], which requires detecting enough events and with enough certainty that it would require planet-scale machinery. > Now graviton chasers find themselves in a peculiar position. On the main facts, everyone is in agreement. One, detecting a quantum event sparked by a gravitational wave is — surprisingly — possible. And two, doing so would not explicitly prove that the gravitational wave is quantized. “Could you make a classical gravitational wave that would produce the same signal? The answer is yes,” said Carney, who along with two co-authors analyzed this type of experiment in Physical Review D(opens a new tab) in February. [0] https://en.wikipedia.org/wiki/Photon_statistics#Sub-Poissonian_light https://en.wikipedia.org/wiki/Photon_statistics#Sub-Poissoni...
- choilive 2y ago
  It sounds like the article is saying we could detect many events without using a planetary scaled detector It mentions a single detector being a 15kg Be bar chilled to near absolute zero. Certainly very very difficult, but not in the realm of sci-fi.
  - itishappy 2y ago
    Right, but this event just confirms gravitational radiation exists (which we already know). It can't tell us how it behaves (is it quantum? it it classical?) without detecting many events in sequence to be able to run statistics on (and if you miss one, your stats are wrong). One bar has a very low probability of detection, we'd need many, hence the expectation of planet-scale machinery.

toomuchtodo 2y ago

> This would be a very big deal. Gravity drive?

cryptonector 2y ago
Nope.

itishappy 2y ago

They can detect an interaction, but they can't prove that it's quantized without (I believe) sub-Poissonian statistics[0], which requires detecting enough events and with enough certainty that it would require planet-scale machinery. > Now graviton chasers find themselves in a peculiar position. On the main facts, everyone is in agreement. One, detecting a quantum event sparked by a gravitational wave is — surprisingly — possible. And two, doing so would not explicitly prove that the gravitational wave is quantized. “Could you make a classical gravitational wave that would produce the same signal? The answer is yes,” said Carney, who along with two co-authors analyzed this type of experiment in Physical Review D(opens a new tab) in February. [0] https://en.wikipedia.org/wiki/Photon_statistics#Sub-Poissonian_light https://en.wikipedia.org/wiki/Photon_statistics#Sub-Poissoni...

choilive 2y ago
It sounds like the article is saying we could detect many events without using a planetary scaled detector It mentions a single detector being a 15kg Be bar chilled to near absolute zero. Certainly very very difficult, but not in the realm of sci-fi.
- itishappy 2y ago
  Right, but this event just confirms gravitational radiation exists (which we already know). It can't tell us how it behaves (is it quantum? it it classical?) without detecting many events in sequence to be able to run statistics on (and if you miss one, your stats are wrong). One bar has a very low probability of detection, we'd need many, hence the expectation of planet-scale machinery.