Wikipedia lists the time complexity of addition as $n$, where $n$ is the number of bits.
Is this a rigid theoretical lower bound? Or is this just the complexity of the current fastest known algorithm. I want to know, because the complexity of addition, underscores all other arithmetic operations and all algorithms which use them.
Is it theoretically impossible, to get an addition algorithm that runs in $o(n)$? Or are we bound to linear complexity for addition.