Signatures being meaningful is a downright American tradition. The country was founded based on signatures. It is never going away.
Crytographic protocols can be added to verify signing, but until every civilian practices perfect opsec (never gonna happen), in-person signatures in front of a notary will always be the way business is done.
Better technology (this program, Photoshop, deepfakes, quantum prime factorization) may actually increase the need for in-person wet signatures.
Post-quantum digital signature algorithms based on lattices are starting to get secure, efficient and based on simple mathematical constructs.
IIRC, the basic construction is you generate a lattice trapdoor matrix R, such that A*(Rt + e) ~= t. Finding an input p with small coefficients, for some t such that Ap = t reduces to one of lattice reduction problems, since it requires a finding "good" basis for the lattice (if you invert A you'll have huge coefficients, so you can't forge it. Having the trapdoor R to make p = Rt + e lets you use the trapdoor to find the preimage, and the gaussian vector e smudges it so that an attacker can't collect signatures to decipher R (this is learning with errors, another problem that reduces to lattice basis.) So the signature is easy to verify, and the trapdoor matrix is relatively small and efficient to compute (iirc a couple megs and <1s)
Are there any widely analyzed implementations that I can use today? Got any links? I'm interested, but I don't think I'd understand without seeing code.
It's a pretty bleak landscape, code-wise. The PALISADE crypto library is an implementation of many of these primitives in C++, but it will be nearly impossible to understand it without reading the papers. I recommend "Trapdoors for Lattices: Simpler, Tighter, Smaller, Faster" [0] and the many papers that build on it. That paper was fairly accessible to a layperson like myself. if you're interested you could play around with it in Sympy or Mathematica.
Crytographic protocols can be added to verify signing, but until every civilian practices perfect opsec (never gonna happen), in-person signatures in front of a notary will always be the way business is done.
Better technology (this program, Photoshop, deepfakes, quantum prime factorization) may actually increase the need for in-person wet signatures.