He seems to be misunderstood. Which is no surprise since he's into unconventional computation - whatever that is[1]. He's well published[2] and has chaired at least one conference on unconventional computing[3]. So that's more than I can say about my career in theoretical computer science. I suspect having unconventional thoughts alone will create some dissonance in related communities. Similar to what Doron Zeilberger gets for his beliefs in Ultrafinitism.
I agree that Akl is talking about a very specific circumstance of UTMs. How many thousands of Mathematicians and Computer Scientists have read that paper in the last 60 years and verified it? If there were ever going to be any true challenge to UTMs it had to be obscure and weird like this. That doesn't mean that I believe he's right, but I don't think he's a crackpot just unconventional.
Your right, I probably shouldn't be so quick to call someone a crackpot.
But still, unless I'm very much mistaken all he's doing is done is to expand the definition of "able to compute a function" to include "able to run fast enough to gather the input data for a function". That might be a useful definition for some things but to use that to claim that "Turing was wrong"?
I agree that Akl is talking about a very specific circumstance of UTMs. How many thousands of Mathematicians and Computer Scientists have read that paper in the last 60 years and verified it? If there were ever going to be any true challenge to UTMs it had to be obscure and weird like this. That doesn't mean that I believe he's right, but I don't think he's a crackpot just unconventional.
[1] http://en.wikipedia.org/wiki/Unconventional_computing
[2] http://research.cs.queensu.ca/Parallel//publications.html#Pu...
[3] http://en.wikipedia.org/wiki/Selim_Akl#Conferences