Limitations of Quantum Computing

Note: First, let me make clear that I am not a computer scientist and while I’ve learned FORTRAN, BASIC and PASCAL in the early 1980’s followed by coursework in quantum chemistry in grad school- and somehow passed– the question of how quantum computation actually computes with qubits remains a mystery to me. Honestly, I’m weary of hearing about it. That said, I do continue to worry about the ever-increasing pressure on the liquid helium tit which quantum computing will definitely lock on to.

An interesting article came out in the current issue of Quantum Magazine giving some straight talk about how quantum computers might actually be used. All of us have been bombarded by breathless predictions of a wondrous future where we can find prime factors of stupidly large numbers and crack very secure cryptography.

Quantum chemistry is about orbiting electrons confined to particular regions of oddly shaped space around a positively charged nucleus, depending on their energy. That is a lifetime of study right there for me. I think I’ll stick to atoms and molecules.

Oh yes, in the early 80’s we used an IBM 360 and submitted our batch jobs as a stack of punch cards. Eventually we were allowed to use the DEC writer for BASIC programming. One sunshiny day an Apple 2 appeared in the chemistry department office. It had 16 K of memory, a green monitor and an external floppy disk drive. There were whispers that 32 and maybe even 64 K were on the horizon. Heady stuff.

The IT guys were surly then too.