Markets are Efficient if and Only if P = NP

Abstract: I prove that if markets are efficient, meaning current prices fully reflect all information available in past prices, then P = NP, meaning every computational problem whose solution can be verified in polynomial time can also be solved in polynomial time. I also prove the converse by showing how we can "program" the market to solve NP-complete problems. Since P probably does not equal NP, markets are probably not efficient. Specifically, markets become increasingly inefficient as the time series lengthens or becomes more frequent. An illustration by way of partitioning the excess returns to momentum strategies based on data availability confirms this prediction.

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This is basically an attack on the efficient market hypothesis - i.e., that markets price in all available information and market moves over the long term accurately reflect the best consensus guess as to the future of a particular company. For background, see Wikipedia:http://en.wikipedia.org/wiki/Efficient-market_hypothesis

What I see as the interesting part of this paper is way in which the author uses market mechanisms - a trading strategy - to test problems as being in the P or NP space, basically equating the market to a type of computational machine. He argues that if the EMF is true, then a properly set up experiment should be able to come up with a solution to an NP problem in polynomial time (implying P=NP).

Read the paper here: http://papers.ssrn.com/sol3/papers.cfm?abstract_id=1773169

Has anyone with the required background read the paper and would like to give a quick summary of the argument?