>>19
The only important thing is that it does not seem to be fundamentally impossible to emulate physical things (which includes the human brain).
Additionally, the human brain is simply an information processing device. There is no reason to believe its sentience derives from its exact behaviour at the molecular level. We may well be able to abstract away most of the complexity of neurons and the brain as a whole, and create a model more suitable for computation by a (probably highly parallel) computer. As an example, signal propagation from a layer of neurons to another can be modeled by a single matrix multiplication followed by a threshold function. Admittedly, this ignores things like memory and such, but the mechanisms behind that are already being discovered and modeled.
In my opinion, you are being far too pessimistic about the eventual possibility of creating artificial minds.