Wednesday, August 14, 2013
Review: Programming the Universe: A Quantum Computer Scientist Takes on the Cosmos
Review: Programming the Universe: A Quantum Computer Scientist Takes on the Cosmos |
| Programming the Universe: A Quantum Computer Scientist Takes on the Cosmos Posted:  By Seth Lloyd Great ideas lead to short papers in peer-reviewed journals. Often, the more prestigious the journal (Science, Nature), the shorter is the paper because of space constraints. Not so good ideas, on the other hand, lead to rambling books. The author is well published and certainly knows this. The premise here is that the universe is a quantum computer. Okay. What is it computing? Seth Lloyd asserts that it is computing itself. From here on the argument becomes circular. The universe is what it is because it is doing what it is doing. Computation is defined in a general way as essentially any kind of atomic change in state. Therefore, interactions (between particles) become synonymous with computation. The problem here is that when you equate something that clearly exists (the universe) with something which in fact really does not (a quantum computer is hypothetical, you cannot go out and buy one) you define the latter in terms most favorable to yourself. So, since an atom flipping states is equivalent to flipping bits, the physical world performs computation. Since the physical world follows quantum laws, it must be a quantum computer. At some point the whole thing becomes an issue of semantics. The section on quantum computing could have been interesting. That quantum computers would potentially be very powerful we know. That they can simultaneously work on multiple questions is also clear enough. That so far they have done no more than factor the number 15 we might infer from the absence of any publicity. Lloyd points out that they should be able to factor a 400 digit number with ease. While I understand that they would do this by working on multiple problems simultaneously, what I am curious to know is how we would extract the desired answer (i.e. |
| You are subscribed to email updates from Shield To stop receiving these emails, you may unsubscribe now. | Email delivery powered by Google |
| Google Inc., 20 West Kinzie, Chicago IL USA 60610 | |
Subscribe to:
Post Comments (Atom)
0 comments:
Post a Comment