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.
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.
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?)