Dwave Systems recently sold their first 128 qubit quantum computer. In 2008 and earlier it was mentioned that AQC (Adiabatic Quantum computers) are not well suited to running the Shor algorithm for breaking encryption. Some people have stated that in 2011 as some kind of gotcha. Geordie Rose (CTO) of Dwave said that explicitly at demonstrations back in 2007 and 2008.

Some quantum computers can or could use Shor’s algorithm to break the main public key cryptosystems. Those based on the difficulty of factoring and the discrete logarithm, but there are still public key cryptosystems which are so far resistent to both quantum and classical attacks (like those based on certain shortest vector in a lattice problems.) Quantum computers can’t break any code in existence.

There are several families of quantum computers.

There is more than one way to make a quantum computer.

Depending upon which way you make it determines what problems it can solve.

Lots of people ask questions like:

How many qubits?

What decoherence time?

Think about an analogue computer vs. a digital one, or a programmable logic chip vs. a general purpose computer.

● Gate model – ‘Standard ‘ model

● Adiabatic Quantum Computation – a close contender

● Cluster state (measurement based) – slightly more obscure

● Topological quantum computing – slightly more obscure

A discussion of quantum computer algorithms

IEEE – Adiabatic Quantum Computation is Equivalent to Standard Quantum Computation

In 2008 Scott Aaronson said that Dwave talking about lining up customers was comically premature. So was 3 years comically premature ? Given that this was the release of an entirely new class of computer I do not think so. There are video games that are delivered with more than a 3 year delay and Microsoft has had delays in releasing operating systems with more than 3 year delays.

Some laser based quantum computers are able to run Shor’s algorithm.

There are many kinds of quantum computers and most cannot or have not run Shor’s algortihm

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Brian Wang is a Futurist Thought Leader and a popular Science blogger with 1 million readers per month. His blog Nextbigfuture.com is ranked #1 Science News Blog. It covers many disruptive technology and trends including Space, Robotics, Artificial Intelligence, Medicine, Anti-aging Biotechnology, and Nanotechnology.

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