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Notes for such efforts:

From https://www.hackerneue.com/item?id=44043518#44053779 re: deep learning poised:

> jax-cfd mentions phiflow

> PhiFlow: https://github.com/tum-pbs/PhiFlow/

>> A differentiable PDE solving framework for machine learning

SymPy can solve ODEs and some PDEs.

sympy.solvers.pde: https://docs.sympy.org/latest/modules/solvers/pde.html

SymPy's sympy.utilities.lambdify.lambdify() compiles things to faster solvers like CPython math module, mpmath, NumPy, SciPy, CuPy, JAX, TensorFlow, SymPy, numexpr, and PyTorch. https://docs.sympy.org/latest/modules/utilities/lambdify.htm...

dynamicslab/pysindy; https://github.com/dynamicslab/pysindy :

> A package for the sparse identification of nonlinear dynamical systems from data

A question about fundamental Anosov flows and CFD in pysindy; due to "Flow Proof Helps Mathematicians Find Stability in Chaos" (2023) https://www.quantamagazine.org/flow-proof-helps-mathematicia... .. https://github.com/dynamicslab/pysindy/issues/383 :

/? site:github.com anosov https://www.google.com/search?q=site%3Agithub.com+anosov

> GitHub topic: quantum-fluids: https://github.com/topics/quantum-fluids

GitHub topic: Gross-Pitaevskii: https://github.com/topics/gross-pitaevskii

OSIRIS-code can simulate laser emissions in plasma, nonlinear optics in plasma,; and supports Checkpointing and thus probably parallelization; https://news.ycombinator.com/context?id=44371059

For simulations of gravity-assisted spacecraft trajectories, in n-body (vortical fluidic) gravity:

> JPL SPICE toolkit: https://naif.jpl.nasa.gov/naif/toolkit.html

> SpiceyPy: https://github.com/AndrewAnnex/SpiceyPy

"Gravity as a fluid dynamic phenomenon in a superfluid quantum space. Fluid quantum gravity and relativity." (2017) https://hal.science/hal-01248015/ :

> [ Bernoulli, Navier-Stokes, Gross-Pitaevskii vortices in a field with curl ]

Shouldn't solving NS also solve for n-body gravity?

Anosov diffeomorphism; hyperbolicity of complex nonlinear dynamic fluid systems, Lyapunov exponents : https://en.wikipedia.org/wiki/Anosov_diffeomorphism

Curl: https://en.wikipedia.org/wiki/Curl_(mathematics)

Vorticity: https://en.wikipedia.org/wiki/Vorticity

Bernoulli's principle: https://en.wikipedia.org/wiki/Bernoulli%27s_principle

Gross-Pitaevskii equation: https://en.wikipedia.org/wiki/Gross%E2%80%93Pitaevskii_equat...

Navier-Stokes equations: https://en.wikipedia.org/wiki/Navier%E2%80%93Stokes_equation...


Um, no?

This is a fine collection of links - much to learn! - but the connection between flow and gravitation is (in my understanding) limited to both being Green's function solutions of a Poisson problem. https://en.wikipedia.org/wiki/Green%27s_function

There are n-body methods for both (gravitation and Lagrangian vortex particle methods), and I find the similarities and differences of those algorithms quite interesting.

But the Fedi paper misses that key connection: they're simply describing a source/sink in potential flow, not some newly discovered link.

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