Chalmers and several other philosophers have made the argument for why consciousness doesn't fit in a physical, functional or objective framework. That's because sensations aren't abstract/descriptive facts or functions. You don't get red, taste, pain from number, extension or chemical makeup. Consciousness is something additional correlated with the biological substrate.
This argument is philosophical nonsense from people fully disconnected from real science. This isn't to say his mind didn't work. It's entirely possible to produce extremely sophisticated mental constructs fully divorced from any connection to reality.
Imagine if nobody had figured out any parallel between programming and math and claimed you couldn't get in any way from the latter to the former!
Dualism is complete and total nonsense. Red is just a label used within a certain pattern of neurons the same way main is a label in a program. If you don't introduce nonsense you don't then find yourself with the hard problem of explaining the result of your own mental gymnastics.
