5 ms·

Quantum entangled photons react to Earth's spin

130 points by wglb 2y ago

westurner 2y ago
> "The core of the matter lays in establishing a reference point for our measurement, where light remains unaffected by Earth's rotational effect. Given our inability to halt Earth's from spinning, we devised a workaround: splitting the optical fiber into two equal-length coils and connecting them via an optical switch," explains lead author Raffaele Silvestri. > By toggling the switch on and off, the researchers could effectively cancel the rotation signal at will, which also allowed them to extend the stability of their large apparatus. "We have basically tricked the light into thinking it's in a non-rotating universe," says Silvestri. "Experimental observation of Earth's rotation with quantum entanglement" (2024) https://www.science.org/doi/10.1126/sciadv.ado0215 https://www.science.org/doi/10.1126/sciadv.ado0215 Sagnac interferometer: https://en.wikipedia.org/wiki/Sagnac_effect https://en.wikipedia.org/wiki/Sagnac_effect
- robin_reala 2y ago
  Given our inability to halt Earth's from spinning Good to have some baseline assumptions!
- las_balas_tres 2y ago
  So almost like an optical wheatstone bridge ?
  - westurner 2y ago
    Wheatstone bridge > Modifications of the basic bridge: https://en.wikipedia.org/wiki/Wheatstone_bridge#Modifications_of_the_basic_bridge https://en.wikipedia.org/wiki/Wheatstone_bridge#Modification... : > Carey Foster bridge, for measuring small resistances; Kelvin bridge, for measuring small four-terminal resistances; Maxwell bridge, and Wien bridge for measuring reactive components; Anderson's bridge, for measuring the self-inductance of the circuit, an advanced form of Maxwell's bridge Is there a rectifier for gravitational waves, and what would that do? Diode bridge > Current flow: https://en.wikipedia.org/wiki/Diode_bridge#Current_flow https://en.wikipedia.org/wiki/Diode_bridge#Current_flow And actually again, electron flow is fluidic: - "How does electricity find the "Path of Least Resistance"?" (and the other paths) https://www.youtube.com/watch?v=C3gnNpYK3lo https://www.youtube.com/watch?v=C3gnNpYK3lo - "Observation of current whirlpools in graphene at room temperature" (2024) https://news.ycombinator.com/item?id=40360684 https://news.ycombinator.com/item?id=40360684 : > How are spin currents and vorticity in electron vortices related? But, back to photons from electrons; like in a wheatstone bridge. Are photonic fields best described with rays, waves, or as fluids in gravitational vortices like in SPH and SQS and CFD? (Superhydrodynamic, Superfluid Quantum Space, Computational Fluid Dynamics) Actually, photons do interact with photons; as phonons in matter: "Quantum vortices of strongly interacting photons" (2024) https://www.science.org/doi/10.1126/science.adh5315 https://www.science.org/doi/10.1126/science.adh5315 https://news.ycombinator.com/item?id=40600762 https://news.ycombinator.com/item?id=40600762 Perhaps there's an even simpler sensor apparatus for this experiment?
pottspotts 2y ago
This is a really great experiment. It's nice to see real work being done on the ground with these kinds of tests and write-ups. I am not a physicist but I imagine this could have implications for gravitational wave detection by improving LIGO's optical sensors, maybe optical sensors in general? Or maybe this could help with tracking time more accurately? Hopefully someone with knowledge can chime in with what this means in practice.
- raziel2701 2y ago
  I don't believe the LIGO experiment is utilizing entangled photons. This experiment is using a very different type of interferometer because they're trying to be sensitive to rotations, whereas LIGO's interferometer is for measuring changes in length. LIGO's biggest problem is how to minimize losses in their mirrors.
  - bowsamic 2y ago
    LIGO could potentially utilise EPR entanglement between photons in different parts of the detector but it does not do so yet. That’s a potential future development. It does use quantum squeezing though
wjb3 2y ago
https://www.science.org/doi/10.1126/sciadv.ado0215 https://www.science.org/doi/10.1126/sciadv.ado0215
stevespang 2y ago
[dead]
robxorb 2y ago
Why would the earths rotation be more significant influence on particles versus its orbit or the solar systems movement around the galactic core, the galaxy's movement, etc? Or do they all, but are unaccounted for in this experiment maybe?
- zygentoma 2y ago
  1/day ~ 1,16e-5 Hz 1/year ~ 3,17e-8 Hz 1/230 million years ~ 1,38e-16 Hz
  - deleted 2y ago
    [deleted]
  - setopt 2y ago
    From this perspective, the next effect that might be relevant is the moons orbit, which should be at a frequency 1.5 orders of magnitude below the Earth spin.
    - zygentoma 2y ago
      Yeah, but for that to be relevant you'd have to set up the experiment on the moon :D
kordlessagain 2y ago
This got me thinking about the old concept of the ether, which was supposedly debunked by the Michelson-Morley experiment. However, I don't think that experiment completely disproved the existence of the ether – it just showed that the classical ether theories were inconsistent with the observed constancy of the speed of light. What if we consider the quantum vacuum, with its virtual particles and fluctuations, as a modern version of the ether? In that case, could the rotation of the Earth interact with this "quantum ether" and influence the propagation of the entangled photons in the Vienna experiment? It's kind of like the idea of frame dragging in general relativity, where the rotation of a massive object affects the surrounding spacetime geometry. Of course, this is just speculation, and any theory involving an ether-like concept would need to be consistent with all the experimental evidence supporting relativity and quantum mechanics. But I think it's still worth exploring these ideas, as they could lead to new insights into the nature of space, time, and gravity.
- api 2y ago
  If there were any kind of ether it would perhaps allow a universal positioning system, basically 3D GPS without supporting infrastructure that worked no matter where you went as long as the system could track you and periodically recalibrate itself vs some landmark. The more sensitive and precise the less recalibration it would ever need.
  - oneshtein 2y ago
    Yes and no. We can measure our speed and direction of movement against the cosmic microwave background, which averages over a much larger area than our visible Universe (if redshift is interpreted as light aging because of ether), but local measurements will be sensitive to local flow only. It's like measuring speed of wind to calculate position. It's possible, to some degree, if you have a map of winds, but its precision is extremely low.
- simiones 2y ago
  The ether was considered to be the physical medium in which light waves propagate, much like air is the medium in which sound waves propagates. The Michelson-Morley experiment (and its successors) proved that it can't be a stationary medium - it would have to move together with the Earth; other experiments had proved that the Earth can't have a very powerful "drag" effect on it either. So, it isn't stationary and it isn't being dragged along with the Earth's movements - almost a contradiction. Special relativity came along and basically gave an explanation of the workings and movement of light that simply didn't need to make any assumptions about the medium in which light waves propagate. The photoelectric effect, showing that light has a dual nature, either particle or wave, pushed the need for an aether to carry it even lower down. QM probably sealed that completely, with the Schrodinger equation as an explanation of the wave-like nature of fundamental particles. I really don't think that this interaction between the spin of the Earth and the properties of photons has any true relationship with the notion of an aether. If you wanted to, it would be easier to call the fields in QFT as a kind of aether, I believe they share more properties with the concept.
andrewp123 2y ago
I’m not sure how interesting this is - of course rotation causes the paths to differ and become measurable. I’ve been wondering about sending photons away from earth and having their paths bend due to gravity (and later have them interfere). That would be interesting because GR would be involved.

130 points by wglb 2y ago

> "The core of the matter lays in establishing a reference point for our measurement, where light remains unaffected by Earth's rotational effect. Given our inability to halt Earth's from spinning, we devised a workaround: splitting the optical fiber into two equal-length coils and connecting them via an optical switch," explains lead author Raffaele Silvestri. > By toggling the switch on and off, the researchers could effectively cancel the rotation signal at will, which also allowed them to extend the stability of their large apparatus. "We have basically tricked the light into thinking it's in a non-rotating universe," says Silvestri. "Experimental observation of Earth's rotation with quantum entanglement" (2024) https://www.science.org/doi/10.1126/sciadv.ado0215 https://www.science.org/doi/10.1126/sciadv.ado0215 Sagnac interferometer: https://en.wikipedia.org/wiki/Sagnac_effect https://en.wikipedia.org/wiki/Sagnac_effect

robin_reala 2y ago
Given our inability to halt Earth's from spinning Good to have some baseline assumptions!
las_balas_tres 2y ago
So almost like an optical wheatstone bridge ?
- westurner 2y ago
  Wheatstone bridge > Modifications of the basic bridge: https://en.wikipedia.org/wiki/Wheatstone_bridge#Modifications_of_the_basic_bridge https://en.wikipedia.org/wiki/Wheatstone_bridge#Modification... : > Carey Foster bridge, for measuring small resistances; Kelvin bridge, for measuring small four-terminal resistances; Maxwell bridge, and Wien bridge for measuring reactive components; Anderson's bridge, for measuring the self-inductance of the circuit, an advanced form of Maxwell's bridge Is there a rectifier for gravitational waves, and what would that do? Diode bridge > Current flow: https://en.wikipedia.org/wiki/Diode_bridge#Current_flow https://en.wikipedia.org/wiki/Diode_bridge#Current_flow And actually again, electron flow is fluidic: - "How does electricity find the "Path of Least Resistance"?" (and the other paths) https://www.youtube.com/watch?v=C3gnNpYK3lo https://www.youtube.com/watch?v=C3gnNpYK3lo - "Observation of current whirlpools in graphene at room temperature" (2024) https://news.ycombinator.com/item?id=40360684 https://news.ycombinator.com/item?id=40360684 : > How are spin currents and vorticity in electron vortices related? But, back to photons from electrons; like in a wheatstone bridge. Are photonic fields best described with rays, waves, or as fluids in gravitational vortices like in SPH and SQS and CFD? (Superhydrodynamic, Superfluid Quantum Space, Computational Fluid Dynamics) Actually, photons do interact with photons; as phonons in matter: "Quantum vortices of strongly interacting photons" (2024) https://www.science.org/doi/10.1126/science.adh5315 https://www.science.org/doi/10.1126/science.adh5315 https://news.ycombinator.com/item?id=40600762 https://news.ycombinator.com/item?id=40600762 Perhaps there's an even simpler sensor apparatus for this experiment?

pottspotts 2y ago

This is a really great experiment. It's nice to see real work being done on the ground with these kinds of tests and write-ups. I am not a physicist but I imagine this could have implications for gravitational wave detection by improving LIGO's optical sensors, maybe optical sensors in general? Or maybe this could help with tracking time more accurately? Hopefully someone with knowledge can chime in with what this means in practice.

raziel2701 2y ago
I don't believe the LIGO experiment is utilizing entangled photons. This experiment is using a very different type of interferometer because they're trying to be sensitive to rotations, whereas LIGO's interferometer is for measuring changes in length. LIGO's biggest problem is how to minimize losses in their mirrors.
- bowsamic 2y ago
  LIGO could potentially utilise EPR entanglement between photons in different parts of the detector but it does not do so yet. That’s a potential future development. It does use quantum squeezing though

wjb3 2y ago

https://www.science.org/doi/10.1126/sciadv.ado0215 https://www.science.org/doi/10.1126/sciadv.ado0215

stevespang 2y ago

[dead]

robxorb 2y ago

Why would the earths rotation be more significant influence on particles versus its orbit or the solar systems movement around the galactic core, the galaxy's movement, etc? Or do they all, but are unaccounted for in this experiment maybe?

zygentoma 2y ago
1/day ~ 1,16e-5 Hz 1/year ~ 3,17e-8 Hz 1/230 million years ~ 1,38e-16 Hz
- deleted 2y ago
  [deleted]
- setopt 2y ago
  From this perspective, the next effect that might be relevant is the moons orbit, which should be at a frequency 1.5 orders of magnitude below the Earth spin.
  - zygentoma 2y ago
    Yeah, but for that to be relevant you'd have to set up the experiment on the moon :D

kordlessagain 2y ago

This got me thinking about the old concept of the ether, which was supposedly debunked by the Michelson-Morley experiment. However, I don't think that experiment completely disproved the existence of the ether – it just showed that the classical ether theories were inconsistent with the observed constancy of the speed of light. What if we consider the quantum vacuum, with its virtual particles and fluctuations, as a modern version of the ether? In that case, could the rotation of the Earth interact with this "quantum ether" and influence the propagation of the entangled photons in the Vienna experiment? It's kind of like the idea of frame dragging in general relativity, where the rotation of a massive object affects the surrounding spacetime geometry. Of course, this is just speculation, and any theory involving an ether-like concept would need to be consistent with all the experimental evidence supporting relativity and quantum mechanics. But I think it's still worth exploring these ideas, as they could lead to new insights into the nature of space, time, and gravity.

api 2y ago
If there were any kind of ether it would perhaps allow a universal positioning system, basically 3D GPS without supporting infrastructure that worked no matter where you went as long as the system could track you and periodically recalibrate itself vs some landmark. The more sensitive and precise the less recalibration it would ever need.
- oneshtein 2y ago
  Yes and no. We can measure our speed and direction of movement against the cosmic microwave background, which averages over a much larger area than our visible Universe (if redshift is interpreted as light aging because of ether), but local measurements will be sensitive to local flow only. It's like measuring speed of wind to calculate position. It's possible, to some degree, if you have a map of winds, but its precision is extremely low.
simiones 2y ago
The ether was considered to be the physical medium in which light waves propagate, much like air is the medium in which sound waves propagates. The Michelson-Morley experiment (and its successors) proved that it can't be a stationary medium - it would have to move together with the Earth; other experiments had proved that the Earth can't have a very powerful "drag" effect on it either. So, it isn't stationary and it isn't being dragged along with the Earth's movements - almost a contradiction. Special relativity came along and basically gave an explanation of the workings and movement of light that simply didn't need to make any assumptions about the medium in which light waves propagate. The photoelectric effect, showing that light has a dual nature, either particle or wave, pushed the need for an aether to carry it even lower down. QM probably sealed that completely, with the Schrodinger equation as an explanation of the wave-like nature of fundamental particles. I really don't think that this interaction between the spin of the Earth and the properties of photons has any true relationship with the notion of an aether. If you wanted to, it would be easier to call the fields in QFT as a kind of aether, I believe they share more properties with the concept.

andrewp123 2y ago

I’m not sure how interesting this is - of course rotation causes the paths to differ and become measurable. I’ve been wondering about sending photons away from earth and having their paths bend due to gravity (and later have them interfere). That would be interesting because GR would be involved.