It is quite possible to have a physical process that cannot be simulated. In fact most complex processes (fluid behavior, for example) cannot be simulated unless we drop the need to know specific outcomes.
Simple example: try to simulate the behavior of Lotto balls. Easy, perhaps, to make a convincing visual animation, but impossible to simulate the important part -- the outcome.
Actually, I believe it will be possible to build electronic consciousness, but I do not expect to see it in my lifetime, and probably not in my children's lifetime. If it happens, the breakthrough concepts will occur as a side effect of trying to make something useful like a traffic light that knows how to maximize throughput.
It is quite possible to have a physical process that cannot be simulated.
I believe it will be possible to build electronic consciousness...
After mulling over these two statements, which may seem contradictory on the surface, I understand what you are saying.
My position might also seem contradictory (though it is not) - because I see profound underlying order in the physical realm, i.e. algorithm at inception. At the same time, I do not see the physical realm as all that there is.
So, IMHO, even if A.I. were to able to simulate consciousness (hard or soft) that would not be the same thing as actualizing a being.