Ciro Santilli @cirosantilli 35

The majority likely comes from physics:

One major application of this classification is that different boundary conditions are suitable for different types of partial differential equations as explained at: which boundary conditions lead to existence and uniqueness of a second order PDE.

Bibliography:

iubmb.onlinelibrary.wiley.com/doi/full/10.1002/bmb.2002.494030030067 Surprises and revelations in biochemistry: 1950-2000 by Perry A. Frey (2006). This should be worth a read.

I can't believe there isn't a YouTube video comparing various substances for each flammability and instability ratings, this would be a huge hit.

Oh, and if it weren't enough, mathematicians have a separate name for the damned nabla symbol : "del" instead of "nabla".

TODO why is it called "Del"? Is is because it is an inverted uppercase delta?

Originally by Springer, but later moved to the European mathematical society.

A wiki that gathers mathematical proofs.

URL: proofwiki.org/wiki/Main_Page

MediaWiki-based.

This appears to be the creator: github.com/externl "Joe George".

A generalized definition of derivative that works on manifolds.

TODO: how does it maintain a single value even across different coordinate charts?