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Entanglement Makes Quantum Particles Measurably Heavier, Says Quantum Theorist
KentuckyFC writes: Physicists have long hoped to unify the two great theories of the 20th century: general relativity and quantum mechanics. And yet a workable theory of quantum gravity is as far away as ever. Now one theorist has discovered that the uniquely quantum property of entanglement does indeed influence a gravitational field and this could pave the way for the first experimental observation of a quantum gravity phenomenon. The discovery is based on the long-known quantum phenomenon in which a single particle can be in two places at the same time. These locations then become entangled — in other words they share the same quantum existence. While formulating this phenomenon within the framework of general relativity, the physicist showed that if the entanglement is tuned in a precise way, it should influence the local gravitational field. In other words, the particle should seem heavier. The effect for a single electron-sized particle is tiny — about one part in 10^37. But it may be possible to magnify the effect using heavier particles, ultrarelativistic particles or even several particles that are already entangled.
Given that two particles can emitted by a single source entangled, sent a long distance apart, and remain entangled,
And that if one particle becomes disentangled the other particle instantaneously becomes disentangled,
If we can measure the entanglement of a particle by its mass,
Then we can communicate faster than light.
But the no-communication theorem states that, during measurement of an entangled quantum state, it is not possible for one observer, by making a measurement of a subsystem of the total state, to communicate information to another observer.
So I think this means that either the no-communication theorem is wrong, or the change in mass of an entangled particle cannot be measured.
(T>t && O(n)--) == sqrt(666)
Either way, I should have it done by lunch time.
Or we could spend some time coming up with additional consequences that might allow indirect tests. For example, does this effect have any consequences for the spectrum of Hawking radiation (just to consider one area were entangled pairs and high gravitational fields are involved)?
How about the structure of the very early universe?
Or are there ridiculously subtle interferometric effects that might allow the detection of the phenomenon? Or other quantum effects?
Consider the Mossbauer Effect as an example of measuring stupidly small energy splittings so many orders of magnitude below any reasonable detector resolution that no doubt some smug bastard made fun of the people doing the hard work of calculating them "because no one will ever be able to measure that!"
Blasphemy is a human right. Blasphemophobia kills.
Your question doesn't have a simple answer, but if it did, it would involve signal-to-noise ratio within a given bandwidth. A radio receiver with a bandwidth in the audio range (~10 kHz) can amplify a signal by about ten trillion times its original power or a few million times its original voltage, before hitting the thermal noise floor of -174 dBm/Hz. These figures aren't exact (for one thing, they neglect the impedance change from a 50-ohm antenna input to an 8-ohm speaker) but the basic idea is correct: the noise floor at 25C in a 50-ohm system is -174 dBm/Hz + 10*log(bandwidth) dBm.
You can improve SNR by making your measurement near absolute zero, but you can't get rid of the noise entirely because some of it isn't strictly thermal in nature. Synchronous demodulation can let you recover information from below the noise floor, given a carrier of known phase. There are other tricks and hacks, but the bottom line is that you are still going to be at least ten or fifteen orders of magnitude away from being able to work with 37 significant figures in any real-world physical measurement. Integration times for such a measurement would have to approach heat-death-of-the-Universe durations.