Everything’s a matrix if u fuck with it hard enough
Tensors
Submitted 2 months ago by fossilesque@mander.xyz to science_memes@mander.xyz
https://mander.xyz/pictrs/image/c0bee4db-ed8d-48ab-9484-b4ad1c0e0a24.jpeg
Comments
muntedcrocodile@lemm.ee 2 months ago
ignotum@lemmy.world 2 months ago
Everything’s a matrix if you realize there is no spoon
UnRelatedBurner@sh.itjust.works 2 months ago
Sadly, they patched the spoon exploit.
marcos@lemmy.world 2 months ago
How you describe a thing is different from what a thing is… A tensor is not a matrix.
And on mathematics, “what a thing is” is a completely useless concept… So, it makes no difference whatsoever.
affiliate@lemmy.world 2 months ago
the “categorical” way of defining tensor products is essentially “that thing that lets you turn multi-linear maps into linear maps”, and linear maps (of finite dimensional vector spaces) are basically matrices anyways. so i don’t see it as much of a stretch to say tensors are matrices.
(can you tell that i never took a physics class?)
mumblerfish@lemmy.world 2 months ago
A tensor is something that transform as a tensor. Gtfo Christoffel symbols.
vzq@lemmy.blahaj.zone 2 months ago
Duck typing ftw
tatterdemalion@programming.dev 2 months ago
Matrices are linear endomorphisms. They are isomorphic to (1,1) tensors, but not any other rank of tensors.
affiliate@lemmy.world 2 months ago
a tensor is a multi-linear map V × … × V × V^^ × … × V^^ → F, and a multi-linear map V × … × V × V^^ × … × V^^ → F is the same as a linear map V ⊗ … ⊗ V ⊗ V^^ ⊗ … ⊗ V^^ → F. and a linear map is ““the same thing as”” a matrix. so in this way, you can associate matrices to tensors. (but the matrices are formed in the tensor space V ⊗ … ⊗ V ⊗ V^^ ⊗ … ⊗ V^^, not in the vector space V.)
theblueredditrefugee@lemmy.dbzer0.com 2 months ago
The difference between a matrix and a 2d array of numbers is the operations that are performed
A tensor really isn’t standardized in the same way so it’s basically just an n-d array in my mind
leisesprecher@feddit.org 2 months ago
It’s all just pointers with semantics attached.
socsa@piefed.social 2 months ago
Vectors with strides.
ZILtoid1991@lemmy.world 2 months ago
You can force a 2D array to be a matrix if you’re clever enough
azi@mander.xyz 2 months ago
good ol’ nominal typing
Hawk@lemmynsfw.com 2 months ago
Well, it would still be a vector. So some standardisation.