Sunday, December 12, 2010

Kirtan with Travis Eliot



I have been attending my yoga teacher and friend Travis Eliot's kirtans on Fridays at Bhakti Yoga Shala in Santa Monica. For those of you who don't know kirtan comes from the Sanskrit and means "to repeat." It is a call-response form of devotional singing. Travis leads the Sanskrit mantras and the audience responds. The mantras are usually short. As Travis explains it through a metaphor, imagine a windshield wiper moving back and forth and in the process cleaning the windshield. The repetition of the mantras are windshield wipers cleaning us spiritually.

I had the pleasure of listening to Daphne Tse who was a guest at Travis's kirtan this past Friday. She came all the way from Bali, shared her beautiful voice and led the second half of the kirtan with her magical "Saraswati Mata." I highly recommend checking out her album "Mata." This was a truly amazing kirtan because two hours got compressed into two minutes. I guess bliss can relativize time. You don't necessarily need to board a spaceship and travel at the speed of light.


Monday, August 9, 2010

Vinay Deolalikar and P vs. NP


The mathematics and computer science blogs are a-buzzin' about Vinay Deolalikar's unverified 100+ page proof that P does not equal NP. This paper is still a draft, and in a very preliminary form. Vinay happens to be a graduate of the University of Southern California. His advisor was P. Vijay Kumar. Dick Lipton talks about it in his blog, as do Scott Aaronson, and Greg Baker. Dave Bacon talks about it over at the Quantum Pontiff blog. I did read a little bit of the paper, and there do seem to some new ideas there. Scott has said that if the proof is correct, i.e., P <> NP, he will supplement an extra $200,000! As you wil recall this problem is one of the famous Clay Millenium Prize problems, and the Clay institute will award one million dollars to the person who solves it. The correctness of this proof would be quite remarkable. I just don't think that the problem's end time as arrived yet. I can place the hardness of this problem on an equal footing with other hard problems such as graph isomorphism, the Riemann Hypothesis, Navier-Stokes etc. Graph theory and complex analysis have been around for well over a hundred years. They are both mature fields of study, where as theoretical computer science has been around for only forty years. Vinay's purported proof must have some groundbreaking calculations and insights to arrive at the final result. The journey in this case is equally as important as the end result. I do hope that the proof is correct.


Tuesday, July 6, 2010

Hiding Quantum Information in the Perfect Code

Todd Brun and I have posted our new paper on arXiv entitled, "Hiding Quantum Information in the Perfect Code." You can find the paper here. I have reproduced the abstract below:

We present and analyze a protocol for quantum steganography where the sender (Alice) encodes her steganographic information into the error syndromes of the perfect (five-qubit) quantum error-correcting code, and sends it to the receiver (Bob) over a depolarizing channel. Alice and Bob share a classical secret key, and hide quantum information in such a way that to an eavesdropper (Eve) without access to the secret key, the quantum message looks like an innocent codeword with a typical sequence of quantum errors. We calculate the average rate of key consumption, and show how the protocol improves in performance as information is spread over multiple codeword blocks. Alice and Bob utilize different encodings to optimize the average number of steganographic bits that they can send to each other while matching the error statistics of the depolarizing channel.

Russian spies and steganography

Here's an interesting article on how Russian spies used steganographic techniques to hide secret messages on public websites. The quantum pontiff e-mailed me the following Wired article a few days ago:

Thursday, June 10, 2010

Quantum Steganography

After two years of research Todd and I have finally submitted our work on quantum steganography. You can find the paper here. There's more to come in a month or so. I've reproduced the abstract from the arXiv website:

Steganography is the process of hiding secret information by embedding it in an "innocent" message. We present protocols for hiding quantum information in a codeword of a quantum error-correcting code passing through a channel. Using either a shared classical secret key or shared entanglement the sender (Alice) disguises her information as errors in the channel. The receiver (Bob) can retrieve the hidden information, but an eavesdropper (Eve) with the power to monitor the channel, but without the secret key, cannot distinguish the message from channel noise. We analyze how difficult it is for Eve to detect the presence of secret messages, and estimate rates of steganographic communication and secret key consumption for certain protocols.

Wednesday, May 5, 2010

What the heck is a quantum computer?

Come hear me ramble on about quantum information science (QIS). This will be a very short and introductory talk. I will first give an overview and history of the field, and then develop some mathematical tools to understand and appreciate David Deutsch's toy quantum algorithm. I may end up explaining quantum teleportation and quantum super-dense coding if time permits. I am dedicating this talk to my adviser Todd Brun and my mentor Dave Bacon.


Details:

http://blog.crashspace.org/2010/05/what-the-heck-is-a-quantum-computer/

Tuesday, January 26, 2010

CaTeGOricalLy NoT! Grand Challenges


I am looking forward to attending Categorically Not which if you have read my past blog posts is a series of salon-based talks started by K. C. Cole. This upcoming event will take place at the Santa Monica Art Studios (a.k.a "The Hangar") on February 7 from 6:30 p.m. till 9:00 p.m. The title of the talk is "Grand Challenges." Doors open at 6:00 p.m., so you can partake in the drinks and food that the organizers kindly provide for. In order to cover the cost of the food/drinks, they ask for a donation of $5.00. I highly recommend arriving early because space is limited and if past events have been any indication, all the seats will get occupied rather quickly. Here is the excerpt from the Categorically Not website:

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Sometimes, it can seem like a grand challenge just to get out of bed in the morning. But the world presents us with an almost overwhelming array of grand challenges made all the more urgent because of the dizzying rate of change in technology and society in general: how to stay out of war and manage resources on an already overcrowded planet; how to deliver medical care and reliable information in a babel of contexts and cultures; how to adapt traditional models of entertainment and communication to thrive in this new world?

For our February 7th Categorically Not!, we will explore grand challenges in journalism, cinema and engineering. Geneva Overholser, director of USC’s Annenberg School of Communication, Pulitzer Prize winner and former ombudsman for the Washington Post will talk about the challenges of trying to figure out how journalism—so essential to democracy—is going to survive when its economic underpinnings are collapsing and its traditional forms are being disrupted by new technologies. This perilous moment for journalism, she will explain, is in fact full of promise.

Just as journalism tries to make sense of life, so does “that bastard child” of literature, the screenplay. USC Cinema School professor Georgia Jeffries—who has written and produced films for HBO, Showtime, USA and Lifetime and been honored with numerous awards—will discuss the challenge writers face in balancing integrity and relevance in a time of extraordinary change in the marketplace. The screenplay explores every facet of human relationships, including gender, race, class, religion, age and youth. It is a demanding canvas, she says, but one with infinite possibility.

Scientists also face challenges in making sense of information—a specialty of Carl Kesselman, Professor of Industrial and Systems Engineering and Co-Director of USC's Center for Health Informatics. His research focuses on grid computing, a technology for creating multi-institutional collaborations and virtual communities that require sharing of data, knowledge and computational infrastructure. The technology aids everything from large physics experiments to limiting damage (and improving responses) to Earthquakes as well as collecting and integrating biomedical data to improve accessibility.