2y ago

Why can't multiple computers be linked to run different probabilities simultaneously to accomplish the same as a quantum computer?

The title says it all. If qubits can be in the position of a 1 and 0, why can't multiple computers using 1s and 0s accomplish the same thing?

11 comments

You can definitely simulate quantum computer with classical computer, but it just won't be as efficient. classical computers would require exponential more space to simulated the process of a quantum computer, which quickly becomes unscalable.
I'd say the key insight with quantum computing is that its algorithms are about choreographing interference patterns among qubits such that wrong answers cancel each other out but right answers reinforce one another. It's not just a matter of trying possibilities in parallel or "running different probabilities simultaneously" - the qubits' states are complex combinations of 0 and 1 states, and they interact with and change one another. Simulating those interactions on a classical computer requires exponentially growing amounts of memory space and time as the quantum computation gets bigger. Trying to divide-and-conquer this simulation over multiple classical computers runs into the need for different parts of the circuit to know about each others' state, limiting how much work can be sectioned off to be done by each computer in the group.
Not just a one and a zero simultaneously, but every decimal in between. All infinity of them. This is the part that doesn't scale well, classical computers don't like infinity. Quantum computers love it.
- Actually, it's explicitly not all in between. The quantum state is a super position, not a smear. It is (ideally) both 1 and 0, but nothing in between.
  It's power comes when you have a multi bit number. 16 bits give 65536 possibilities. A classical computer would have to check each one individually to process them all. A quantum computer does them all in 1 go.
  While it gets very messy in the implementation, quantum computers are still binary, just quantum binary. No infinities needed
- i believe what you're thinking is analog computers
Thanks for the insights, guys. My brain is a bit more wrinkly now.
It won't be the same as a quantum computer but something like this has been done before (albeit illegally):
Carna botnet - Podcast and info
i don't know, but aren't supercomputers already doing that with many cores except that kinda has a limit?

11 comments