Distributed quantum computing at QCE26 came down to the cost of a link

This guide follows 34 talks on modular and distributed quantum computing at IEEE Quantum Week 2026 in Toronto. Almost every one priced the link between machines, and almost none could measure that price on real hardware. On the afternoon of Sunday 13 September, in Room 717B of the Metro Toronto Convention Centre, Mahdi Chehimi of the American University of Beirut put up a table about distributed quantum computing. It showed what happens when a quantum program is cut in two so that each half fits on a smaller machine. Every cut CZ gate multiplied the number of runs by nine. A job of 1,000 runs became 6.56 million at four cuts, and took 30 hours at six. Chehimi’s table priced the idea at the centre of this field, which starts from the plain fact that useful quantum computers will need far more qubits than any one chip holds. A superconducting chip needs wires that run down into a fridge colder than deep space. Both the wires and the cold run out of room. They do so long before a chip gets as big as useful programs need, so the field wants one large machine built from many small ones, called…