Scott Aaronson Associate Professor, EECS Quantum Computers and Beyond

Moores Law

Extrapolating: Robot uprising?

But even a killer robot would still be merely a Turing machine, operating on principles laid down in the 1930s… =

Is there any feasible way to solve these problems, consistent with the laws of physics? And its conjectured that thousands of interesting problems are inherently intractable for Turing machines…

Relativity Computer DONE

Zenos Computer STEP 1 STEP 2 STEP 3 STEP 4 STEP 5 Time (seconds)

Time Travel Computer S. Aaronson and J. Watrous. Closed Timelike Curves Make Quantum and Classical Computing Equivalent, Proceedings of the Royal Society A 465: , arXiv:

What weve learned from quantum computers so far: 15 = 3 × 5 (with high probability)

Linear-Optical Quantum Computing My student Alex Arkhipov and I recently proposed an experiment, which involves generating n identical photons, passing them through a network of beamsplitters, then measuring where they end up Our proposal almost certainly wouldnt yield a universal quantum computerand indeed, it seems a lot easier to implement Nevertheless, we give complexity-theoretic evidence that our experiment would solve some sampling problem thats classically intractable Groups in Brisbane, Australia and Imperial College London are currently working to implement our experiment

Summary 1.From a theoretical standpoint, modern computers are all the same slop: polynomial- time Turing machines 2.We can imagine computers that vastly exceed those (by using closed timelike curves, etc.) 3.But going even a tiny bit beyond polynomial-time Turing machines (say, with linear-optical quantum computers) is a great experimental challenge