They stated that the qubits they are working with are topological defects similar to knots. OK, but defects in the topology of what? Spacetime? The Maxwell potential? Hilbert phase space?

How many topological qubits are needed to produce a logical qubit?

Then they mentioned nanowires connecting the topological qubits. Are those just tiny wires, or is there a quantum phenomenon associated with them? How is the readout done? I assume it's destructive?

As an aside, with all the subtle research being done on qubits and entanglement, I would have expected some clarity in the fundamental interpretation of QM by now (Copenhagen, Manyworlds, Bohmian), but I haven't heard of anything new for awhile.

It looks like "topological qubits" that are used in MSFT breakthrough is a sort of "surface-spread" qubits, because they are two dimensional structures. They are then "braided" instead of "entangled" to specify a problem to solve.

What is interesting here is that error correction for temperature fluctuations amounts to give these braids wider separation (in actual space). Which, on one hand, looks like simplification of the solution, but, on the other hand, still requires more space just like additional qubits in regular quantum computer.