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Cyaegha

Re:Solving the Multicore Dilemma on Sunday October 14, 2012 @10:21AM (#4651477)
For that construction to work, these 'virtual' nodes need to exist in the poset. Your poset is just the vertex set of your DAG ordered by reachability, so they don't exist. I think your intuition is good, but the mathematics just doesn't add up. Perhaps you should look into things like trace monoids, pomsets and petri nets?

Please understand that I'm not trying to be mean here. You mention you've been applying for grants to work on this, but if you don't explain the mathematics adequately or demonstrate how it differs from existing formalisms then I imagine people are just going to reject you instantly. I would suggest seriously trying to formalise some of this stuff in a proof assistant like Coq. That'll quickly tell you if your theory works or not.

Re:Solving the Multicore Dilemma on Sunday October 14, 2012 @12:09AM (#4650609)
All finite lattices are posets, but not all finite posets are lattices, so I stand by the usage.

Yes obviously, but nowhere is it clear that you actually have a lattice of any kind. Specifically, I see no reason why pruning DAGs of unused computations would yield a lattice, and this is a result you seem to rely on. Program lattice does indeed sound nicer than program bounded poset, but I would be more wary about misusing terminology than having a nice name! :)

Re:Solving the Multicore Dilemma on Saturday October 13, 2012 @10:59PM (#4650446)
You state that:

A lattice is a partial ordering with a single unique "top element" (least upper bound) and a single unique "bottom element" (greatest lower bound). Every node in the lattice is reachable by following some directed path from the single least upper bound, and there is a directed path from every node in the lattice to the single least lower bound.

A lattice is a poset where binary joins and meets exist. You define a bounded poset not a lattice. In general a lattice need not have either a top element or a bottom element, although all finite lattices are complete and thus do have top and bottom elements. The second sentence is also redundant, because for any element x of a lattice x ≤ ⊤, so why talk about paths?

Re:Solving the Multicore Dilemma on Saturday October 13, 2012 @10:23PM (#4650394)
He has additional ideas - the problem is they're mostly nonsense. For example, if you look at the page where he tries to explain what he means by program lattices and lattice based computing, he gets the definition of a lattice wrong! (despite actually linking to a correct definition!)
Re:Solving the Multicore Dilemma on Saturday October 13, 2012 @06:57PM (#4650031)
Maybe I'm wrong, but it seems to me that most of this guy's ideas are either a bit half-baked or simply flat out wrong.

Consider the argument for his proposed language being Turing complete on the flow manifesto page. He claims that this follows from the Böhm-Jacopini theorem. However the Böhm-Jacopini theorem requires variable assignment is allowed in the subprograms (which does not appear to be the case in flow), and without this the theorem does not hold, as this paper by Kozen demonstrates: www.cs.cornell.edu/~kozen/papers/bohmjacopini.pdf. Then he goes on to argue that order duality implies the existence of a selection operator in flow, which doesn't seem to make any sense.

I think it's telling that he has been working on this since 2010, yet has no decent proofs of his claims, nor any working implementation.