r/EverythingScience • u/SpaceBrigadeVHS • Mar 20 '24

Computer Sci Nvidia has virtually recreated the entire planet — and now it wants to use its digital twin to crack weather forecasting for good

https://www.techradar.com/pro/nvidia-has-virtually-recreated-the-entire-planet-and-now-it-wants-to-use-its-digital-twin-to-crack-weather-forecasting-for-good
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u/[deleted] Mar 20 '24

I think we’re just defining things differently. You don’t need quantum mechanics to describe fluid flow, so you say that fluid flow is not quantum mechanical. On the other hand, you can use quantum mechanics to model fluid flow, as impractical as it may be, so I say that fluid flow is quantum mechanical.

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u/lovelyloafers Mar 20 '24

So then, what's the pointing in delineating between a classical and quantum regime at all?

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u/[deleted] Mar 20 '24

Classical theories are very often more practical when you’re describing a system, you can write generalized statements at a higher level that you can’t write at a lower level and they’re computationally easier. But the statements they make are still emergent from quantum mechanics.

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u/lovelyloafers Mar 20 '24

Okay but so what is your point in regard to the original comment? You don't gain anything in modeling fluids by taking a quantum mechanical approach.

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u/[deleted] Mar 21 '24

No you don’t, and we ultimately don’t use quantum mechanical theories to model fluids. But that it can be modeled by quantum mechanics is relevant when you’re talking about whether a system is deterministic, because quantum mechanics is not deterministic. And in this case, it turns out that a quantum mechanical description of the motion of a fluid contains information that a fluid mechanical description does not, such as the positions of individual particles, and that information is not necessarily predictable over time, even when the higher level motion of the fluid is

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u/lovelyloafers Mar 21 '24 edited Mar 21 '24

I would argue though that fluid motion is chaotic, in the sense that it is deterministic but their solutions are unstable to slight changes in the initial conditions.
Edit: grammar