6 hours ago by canjobear
What hypothesis is being tested here? Is there any theory that predicts that large objects won't behave like waves if they are properly isolated from the environment?
5 hours ago by tooltower
Indeed, there are variations on standard quantum mechanics that postulate that large systems can spontaneously collapse their wave functions. E.g. https://en.wikipedia.org/wiki/Objective-collapse_theory
Nobody is really expecting large objects to behave differently, but somebody should still check.
5 hours ago by whatshisface
All the large objects are made up of smaller objects...
5 hours ago by kordlessagain
That’s the current hypothesis, at least.
2 hours ago by bawolff
I think the big thing is many humans cant wrap their mind around qm. Lots of people are like, its ok as long as it only applies to microscopic quantities but doing a big object would force them to confront reality more head on.
5 hours ago by undefined
6 hours ago by undefined
6 hours ago by perihelions
Why do they need vacuum pumps at all? Do the materials of the satellite itself offgas too much?
6 hours ago by mdturnerphys
Good question. They say that they need 10^-11 pascals. The pressure in low earth orbit is 10^-8 pascals [0], but the suggestion is to put it at a Langrange point (L1 or L2), where the pressure should be much below that.
[0] https://en.wikipedia.org/wiki/Orders_of_magnitude_(pressure)
2 hours ago by ThomPete
china is already fully engaged in this
https://www.scientificamerican.com/article/china-reaches-new...
4 hours ago by madengr
I thought macroscopic quantum behavior had been demonstrated in a comb-like resonator? The vibrating teeth on the comb would transition from one side to the other without passing through the center.
6 hours ago by whatshisface
This seems like such a bad idea, the equivalent of catapulting ever greater rocks on the moon to test Newton's laws.
4 hours ago by krastanov
Funny thing is that we have been running other experiments you would find just as silly: test gravitational attraction between human-scale objects with ridiculously expensive and sensitive equipment, test whether there is a difference between gravitational and inertial mass, interfere neutrons(?) after they pass through slightly different gravitational fields on Earth. My favorite is measuring the dipole moment of the electron (like, duh, of course the electron does not have a dipole moment).
All of these tests are silly if you believe the theories of the day. The vast majority of such tests in history have simply confirmed the theory of the day. And also, there are a small handful of them that have spurred the most amazing intellectual explosion in the history of this planet (Special/General relativity and Quantum theory).
Also, the investment permits the contractors for the experiment to create an industrial base crucial for applications in the general economy.
an hour ago by evanb
The standard model of particle physics does predict the electron should have an EDM.
https://en.wikipedia.org/wiki/Electron_electric_dipole_momen...
However, a nonzero electron EDM indicates P and CP breaking; in the standard model it’s generated through loop effects from the CP violation in the CKM matrix, making it very very small (1e-38 e•cm).
The experimental results are that it’s zero with a precision of ~1e-28 e•cm. So, there’s TEN orders of magnitude between experiment and theory—-that makes it not a particularly silly thing to measure, but a particularly appealing experimental target: lots of models of new physics predict something substantially larger than 1e-38, and the small value in the standard model makes a nonzero measurement an obvious signal.
Contrast the muon g-2 measurements, for example, where a new lattice QCD calculation of standard-model effects claims to adjust the prediction in the 10th decimal, reducing the tension to 1.5 sigma. If an electron EDM is found anywhere in the next… 8 or 9 orders of magnitude, it’d be an inarguable sign of new physics.
2 hours ago by AlotOfReading
More experiments are always worthwhile, but from a practical perspective funding is a zero-sum game with a small number of finite pots. The question being raised isn't whether this proposal is worthwhile "in general", but instead whether it's a good use of finite finding vs other potential science.
Given the immense cost and the lack of serious reasons to expect otherwise, I think it's a pretty reasonable question to ask.
4 hours ago by undefined
4 hours ago by AlexCoventry
I wonder how precise the measurement of those trajectories would need to be, to detect deviations due to special/general relativity.
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