david jon furbish

@davidjonfurbish.bsky.social

emeritus professor studying statistical physics of sediment transport & science philosophy essays and ebook preview at: https://my.vanderbilt.edu/davidjonfurbish/ author of Fluid Physics in Geology: https://academic.oup.com/book/40895?login=false

This declaration on math and AI reminds me that, in science, an accurate prediction of the behavior/state of a system in the absence of explanation might be practically useful, but it is scientifically worthless. See also the “problem (fallacy) of induction” vs the elements of critical rationalism.

Terence Tao@teorth.bsky.social · last wk.

A group of 25 Fields Medalists, including myself, have made a joint declaration on Math and AI: mathandai.org . We welcome additional signatories. See also this article in the Economist announcing the declaration: www.economist.com/science-and-...

Interesting thread by @teorth.bsky.social about LLM math proofs inhibiting math research by giving an answer that's correct but doesn't improve understanding. Speculation online is that he's not just musing, some AI lab showed him a Navier-Stokes solution and he's trying to nudge them a better way.

Terence Tao (@tao@mathstodon.xyz)

A concrete example of how AI advances in solving key open problems could inihibit the future development of a mathematical field can be found in the global regularity problem for the incompressible Na...

mathstodon.xyz

These three 6 m stems of Paulownia tomentosa (princess tree or empress tree or foxglove tree) started as small shoots in June. Native to China, the deciduous hardwood princess tree is among the fastest growing in the world, and it invasively thrives in TN.

Pic of three stems of princess tree with large leaves growing in front of gray cabin, with Australian Shepherd standing near the base of the trees

To reinforce two well-known points: to advocate for “AI literacy” is to support a bait-and-switch marketing ploy having nothing to do with learning or scholarship to adopt an opt-out versus opt-in policy defies principles of consent and insults students’ sensibilities on the matter at the outset

david jon furbish@davidjonfurbish.bsky.social · 2mo ago

Hey, Professor, are you still imagining that your university is something different from a full corporate enterprise — led by business administrators far removed from the actual doing of teaching and scholarship — trying to force AI into all aspects of academic activities?

Because of the continuing relevance of B. K. Forscher’s classic 1963 allegorical Letter in Science, “Chaos in the Brickyard,” we “updated” it in 2020. Science rejected our Letter, and you will see a likely contributing factor when we describe “storage places” 😂 “The Brickyard in 2020”

cdn.vanderbilt.edu

I am skeptical of the premise that reasoning evolved as a capacity for persuasion and not as a means of discovery. And the authors have a rosier view of doing science than what actually occurs. Nonetheless the arguments presented in the paper do not hinge on these points and it is a delightful read.

Rob Sica@robsica.bsky.social · last mo.

✨"Social epistemology needs a theory of reasoning that would explain the type of social interactions it describes as the root of scientific knowledge production. And here is the good news: the argumentative theory of reasoning is a rather good candidate for that purpose." philpapers.org/rec/HEITUE

I wish more people talked about how universities embraced AI and this helped create a perfect storm for supposedly most students now cheating using chatbots. Many ways of undetected cheating have always existed, but were never promoted as ways to study or write. The complicity is flagrant. 1/

Olivia Guest · Ολίβια Γκεστ@olivia.science · 7mo ago

got inspired by some questions from phd students the other day — and also really irritated by senior academics who seem to refuse to get the issues and continue to blame students; hope useful for you! 🩷 olivia.science/cheating

✨"Social epistemology needs a theory of reasoning that would explain the type of social interactions it describes as the root of scientific knowledge production. And here is the good news: the argumentative theory of reasoning is a rather good candidate for that purpose." philpapers.org/rec/HEITUE

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Excited to share two preprints for companion papers that examine the statistics of bedload motion! We used high-resolution imagery to capture grain tracks from flume experiments across a range of fluid shear stresses. We also subject the sand bed to "stress history" to see how grain motion changes.

Three-panel figure from a scientific paper. The top panel (a) shows example sediment trajectories from a particle-tracking analysis overlaid onto an image of the underlying sediment bed; note the appearance of fluorescing sand grains illuminated by the ultraviolet light. These trajectories represent transport conditions over a subset of the sediment bed that is 1.2 times the threshold for grain motion. The middle panel (b) shows the same sediment trajectories as depicted in panel (a) with markers indicating periods of motion (blue) and rest (red); one of the trajectories is highlighted in yellow. This highlighted track is further examined in panel (c), which shows a timeseries of streamwise position (black line) and velocity (red/blue markers) for the example trajectory illustrating segments of motion and rest.

I usually compose footnotes in a manner befitting their normally intended purpose: to support or elaborate material in the main text. But I also view certain footnotes as opportunities to drop serious snark. Here is one of my favorite recently composed footnotes, with context.

Consider rain splash transport as an example, and recall the one-dimensional entrainment form of the Exner equation...

Focusing on the advective term in (1)...

where D = k E / c_b.  Thus the advective term looks like diffusion as defined mathematically.  Whereas it is correct to say that (2) is a diffusion equation, it is incorrect to say that this equation represents the effects of particle diffusion.  The effects of particle diffusion are described by the last term in (1), a point that we fully examine in Chapter 11.  A similar interpretation applies to soil creep, where (2) arises from the assumption that the vertically integrated soil flux is proportional to the local land-surface slope.

The derivative on the right side of (2) often is referred to as a diffusive term, likely in analogy with a conventional advection--diffusion equation.  This is correct in a mathematical sense, and perhaps intended to refer to the idea that ``diffusive smoothing'' of the function < zeta > occurs according to the mathematical algorithm defined by a diffusion equation.  But in a physical sense related to transport, the derivative on the right side of (2) is actually an advective term.  It looks mathematically diffusive only because the average particle displacement is proportional to the land-surface slope.\footnote{\textcolor{blue}{This point of confusion seems to reflect a broader misunderstanding of the meaning of advection.  The popular, heuristically confused ``stream power model'' of land-surface evolution includes a ``diffusive'' term as in (2) and a term involving the product of the local land-surface slope and the upstream catchment area.  This latter term is often referred to as an advective term, but it has nothing to do with advection.  It is in fact a local sink term.  Moreover, for physical reasons the two terms are not additive as normally assumed.}}