5 ms·
As far as QC scalability, the thing I wonder about is the cost of maintaining full entanglement of N qubits as N grows large. The debbie-downer perspective wou
by gregfjohnson 7y ago
As far as QC scalability, the thing I wonder about is the cost of maintaining full entanglement of N qubits as N grows large.
The debbie-downer perspective would be that for each additional qubit you add, you effectively double the cost of isolation from the environment, quantum error correction schemes, etc.
So, while compute power for quantum algorithms grows exponentially in N, so would the cost of operating the machine.
Do people who work in QC see this as a concern? Are there scientific arguments or engineering insights that lessen or obviate this concern?
For your enjoyment and amusement, here is a QC-related show-HN!
"An elementary proof of a key lemma in Shor's quantum factoring algorithm": http://gregfjohnson.com/qft.html http://gregfjohnson.com/qft.html
- jcoffland 7y ago> The debbie-downer perspective would be that for each additional qubit you add, you effectively double the cost of isolation from the environment, quantum error correction schemes, etc. This is exactly my concern with quantum computing. Not only might it get more expensive but it may simply be limited by the laws of our universe. If the difficulty of entangling and isolating qbits increases exponentially with the number of bits then quantum computing could be a dead end. You may still get some nice results of you can decrease the exponent. I'd love to be proven wrong.
- johncolanduoni 7y agoThis is the primary concern and barrier to most realizations of quantum computers including Google’s most recent efforts, though there are exceptions like linear optical quantum computing which have different problems. So for people working in QC this is in fact the perspective, though they are mostly optimistic that we can continue to engineer/discover better solutions to this problem.