SH: "We understand function well enough"

I strongly disagree. I would maintain that we do not understand function well enough and it is this lack of understanding that makes it appear as if there is an explanatory gap between physical theory and mental observation. Your comment is  a simple dismissal of my point without any detailed rebuttal, perhaps I did not make my argument sufficiently clear.  The crucial point in my argument is that current physical theory describes the universe as a four dimensional block structure with all events already fixed (Petkov 2006). In a block universe there is no change, no experience or becoming.  The block universe has "functions" in the sense that different times have different states but it has no way of getting from one state to another, it has no way for the observer to move through time to actually enact functions.  In our current understanding of the physical world functions are static and do not evolve so an "explanatory gap" between a functional description and our experience is inevitable.

Philosophers used to be able to brush aside the block universe description as somehow self-evidently absurd but in the past three years the existence of time has been confirmed experimentally by a rash of experiments that show electrons can interfere with their own, historical selves. The experiments use attosecond laser pulses "..for following the dynamics of time-dependent superposition of states" (Remetteri et al 2006), effectively creating a double-slit in the time domain (Lindner et al 2006, Ishikawa 2006).  These double slit experiments in the time domain are demonstrating the existence of time in the same way as the classical, spatial, double slit experiment provides a quantum mechanical demonstration of the existence of space.  They confirm the prediction of an existent time dimension that is implicit in special relativity theory (Petkov 2006).

If the block universe exists then as Weyl and recently Petkov(2002) have pointed out physicalism currently has no explanation for experience, becoming and change.  In a block universe change appears to be an unexplained property of the observer (Weyl 1920, Petkov 2002).  This absence of a widely accepted reason for change in physical theory does not mean that physicalism is false.  It simply means that physical theory is incomplete because it is unable to explain even how a traffic light actually changes state.  Physical theory needs to be developed so that change can be accommodated as a separate phenomenon from dimensional time. 

As a possible direction for the future amendment of physical theory Petkov (2002) suggests that  "it is natural to expect that the consciousness "operates' at a sub-micro level where the frozenness of our macro reality does not hold any more".  As an alternative, I would suggest, on purely empirical grounds, that there are more ways of ordering events than are permitted by the four dimensions of space-time (see <a href="http://newempiricism.blogspot.com/2009/02/time-and-conscious-experience.html">Time and conscious experience</a>). 

SH: "No, the problem is that feeling is correlated with time and change in biological systems but no one can explain how or why."

Stating that "feeling" is correlated with physical change is stating that feeling is correlated with an unknown physical phenomenon and hence, as yet, feeling is inexplicable by physical theory. So I agree that there is a problem explaining "feeling" but would point out that this problem arises because physical theory is incomplete, not because there is any fundamental separation between the physical and the mental.

References

Ishikawa, K.L. (2006) Temporal Young’s interference experiment by attosecond double and triple soft-x-ray pulses. PHYSICAL REVIEW A 74, 023806 ͑2006͒

Lindner, F., Schaetzel, F.G., Walther, H., Baltuska, A., Goulielmakis, E., Krausz, F., Milosevic, D.B., Bauer, D., Becker, W., and Paulus, G.G.. (2005) Attosecond double-slit experiment. Phys.Rev.Lett. 95,040401 (2005)

Petkov, V. (2002). Montreal Inter-University Seminar on the History and Philosophy of Science. http://alcor.concordia.ca/~vpetkov/absolute.html

Petkov, V. (2006). Is There an Alternative to the Block Universe View?, in: D. Dieks and M. Redei (eds.), The Ontology of Spacetime. Series on the Philosophy and Foundations of Physics (Elsevier, Amsterdam) http://philsci-archive.pitt.edu/archive/00002408/

Remetteri, T., Johnsson, P., Mauritsson, J., Varjui, K., Lepine, F., Gustafsson, E., Kling, M., Khan, J., Lopez-Martens, R., Schafer, K.J., Vrakking, M.J.J. and A. L'Huillier. (2006) Attosecond electron wave packet
interferometry. Nature Physics VOL 2 323-326 MAY 2006