By Serge-Paul Carrasco on October 25, 2013

How to Compute with Schroedinger’s Cat – An Introduction to Quantum Computing

(T) The Schroedinger’s cat experiment presents a cat that is both alive and dead and illustrates the superposition of states, a property of a quantum system. This week, Eleanor G. Rieffel from the Quantum Artificial Intelligence Lab (QuAIL) at NASA Ames Research Center gave a talk at the Silicon Valley Quantum Computing Meet-Up that meets at Hacker Dojo in Mountain View. The NASA Armes Research Center hosts the Quantum Artificial Intelligence Lab (a collaborative effort among NASA, Google, and Universities Space Research Association (USRA)) to explore the potential for quantum computers to tackle “NP-hard” optimization problems. The lab houses a 512-qubit D-Wave Two™ quantum computer.

Doctor Riefflel has a Ph.D. from UCLA and is the author with Wolfgang Polak of “Quantum Computing: A Gentle Introduction” published by MIT press.

Following is the abstract of one of her latest contributions “The Quantum Frontier” that gives a good introduction to quantum information processing, that she explained in her talk this week:

“The success of the abstract model of computation, in terms of bits, logical operations, programming language constructs, and the like, makes it easy to forget that computation is a physical process. Our cherished notions of computation and information are grounded in classical mechanics, but the physics underlying our world is quantum. In the early 80s, researchers began to ask how computation would change if we adopted a quantum mechanical, instead of a classical mechanical, view of computation. Slowly, a new picture of computation arose, one that gave rise to a variety of faster algorithms, novel cryptographic mechanisms, and alternative methods of communication. Small quantum information processing devices have been built, and efforts are underway to build larger ones. Even apart from the existence of these devices, the quantum view on information processing has provided significant insight into the nature of computation and information, and a deeper understanding of the physics of our universe and its connections with computation.

We start by describing aspects of quantum mechanics that are at the heart of a quantum view of information processing. We give our own idiosyncratic view of a number of these topics in the hopes of correcting common misconceptions and highlighting aspects that are often overlooked. A number of the phenomena described were initially viewed as oddities of quantum mechanics, whose meaning was best left to philosophers, topics that respectable physicists would avoid or, at best, talk about only over a late night beer. It was quantum information processing, first quantum cryptography and then, more dramatically, quantum computing, that turned the tables and showed that these oddities could be put to practical effect. It is these applications we describe next.

We conclude with a section describing some of the many questions left for future work, especially the mysteries surrounding where the power of quantum information ultimately comes from.”

The full paper is available here in pdf: QuantumFrontier

NASA and Google have recently released a fun video on Quantum Computing: