Coffeebreak Links 291209

More quantum picks from the recent ArXiv preprints.
Something to read when you have to stay up ’til midnight…

Theory of Macroscopic Quantum Dynamics in High-Tc Josephson Junctions
The Tunneling dynamics in s/d-wave hybrid junctions is difficult due to the non-ideal barrier interface and the unknown effects of quasiparticles. This paper furthers the compilation of a theory to describe these unusual junctions.

High-performance Energy Minimization with Applications to Adiabatic Quantum Computing

Tunneling-induced coherent electron population transfer in an asymmetric quantum well

Phase gate of one qubit simultaneously controlling n qubits in a cavity or coupled to a resonator
– Franco Nori’s latest work.

A Quantum-Bayesian Route to Quantum-State Space

Theory of two-dimensional macroscopic quantum tunneling in a Josephson junction coupled with an LC circuit
-More from Kawabata (and Bauch)

Measurement of the Josephson Junction Phase Qubits by a Microstrip Resonator

Switchable ultrastrong coupling in circuit QED

These things are scaling pretty quickly…

Via Michael Nielsen:

Quantum Computers

From the website:

“Maybe you’ve never heard of Quantum Computers before and are partial to purchasing from another company that might have advertising everywhere you look.”

Ah, shucks… so that’s where I was going wrong.

Media coverage, skew, and general not-in-the-Christmas-spirit ranting

Bah, humbug.

A little earlier I nonchalantly and lazily microblogged using the oh-so-professional channel of my Facebook status about something that slightly irritated me whilst watching the news. Here was what I wrote:

One attempted act of terrorism: Almost 24/7 news coverage. Thousands of scientific breakthroughs every day: Not even a few minutes of airtime. No wonder the general public feel isolated from science, in fear of technological advancement and generally depressed at the state of the world…

Anyway, seeing as the comment sparked quite an interesting conversation, I thought I’d relay these thoughts on this, my slightly more traditional soap-box haunt.

Obviously my comment pertained to the recent attempt to bring down a plane travelling from Amsterdam to Detroit. How much about this could there possibly be to report? Hours worth of television time, apparently.

It just depresses me that the news programs, day after day, cover crime, terrorism, war and political unrest as their main stories, then attempt to lighten this doom-riddled cake of hopelessness with a cherry in the form of a ridiculous human factor story about some family’s cat being rescued from a tree (or something equally banal). Earlier today I watched a story about freak weather in the UK – the seemingly important aspect of this being a woman who gave birth in an ambulance because it was stuck in the snow on a sliproad on the A14. Oh, and then there’s 10 minutes of football news!! If I were sat at a desk I would somewhat non-figuratively be slamming my head against it at this point. Luckily for me I’m on a sofa.

I’m not just going to have a long rant here about what I think the news SHOULD be covering, I think that much is pretty obvious from my list of interests ~superconducting flux qubits, yey!~ <-excuse the voices in my head.
Moreover, I'm wondering: What can we actually DO about it?

During my time in a University setting, I think I've only once been invited to a seminar by a person from the Press (in this case it was Radio 4). I think that the press just do not engage enough with scientists. There is so much cool research just waiting to be explored and popularised. There is also a large body of enthusiastic, young PhD students who would be willing to talk about what they are doing, which would not only help popularise their respective subjects, but also break that 'mad professor / scientist' stereotype which seems to still be hanging around a couple hundred years after it was actually representative.

However, until the 'media approaching scientists' kind of thing reaches a critical mass, it will be up to the scientists to shout louder and more ingeniously to make people take note. It will be up to them to chase down the media opportunities.

And I believe that there is a somewhat insidious problem here – primarily that it's not considered a worthwhile activity amongst science/engineering peers to communicate and popularise your research. Carl Sagan et al. are very much the exception rather than the rule. Popularisation is certainly not taught alongside science, or encouraged, even though there are lots of external grants available for this kind of thing. We rely on the rebellious defector amongst academics to propagate the enthusiasm. Instead, we should be supporting those who wish to act as spokespeople for their research.

A lot of media types are also looking for the ‘scare story’ angle. They will try every trick on the book to hype the negative angle of your research, especially of you are working in disruptive or controversial technology areas. I think that academics should be trained to answer media questions a bit like politicians: Get across the positive impact at all costs (short of actually, you know, lying..). And for goodness sake don’t mention Skynet. Or nano greygoo*ahem* tech. It’s ‘submicron’ or ‘molecular’ engineering, guys!

Ultimately, the goverment hands out the money to the funding councils, and therefore if we as scientists aren’t in the forefront of their minds (I mean look, we’re competing with the NHS, the education system, the war in Afghanistan, etc….), if they don’t see our science and go “Wow, you know – that’s not only the future of our country, but it’s actually pretty interesting too”, then funding for our research will indeed be cut.

So go out there and tell people that your research, be it Physics or whatever, is awesome. In any way you can. Ignore anyone who tells you that it isn’t worthwhile. And if you do it right – if you do it *really* right – then those people might just mention it to their friends the next time they have tea and cake 😉


Note: On this topic with a slightly more transhumanist slant, inspired by the conversation, Stuart has also written a blogpost.

Merry Christmas by the way people.

Excellent model for a research institution

Via Brain Waves

The McGovern Institute for Brain Research at MIT

Click on the link to watch a very inspirational 20 minute video about the research and wider goals of the Institute. Ed Boyen is featured with his Opto-genetic technology. I saw him talk at the Singularity Summit earlier this year. Really interesting stuff. Not only is the science here very impressive, but the way these people respect their colleagues and consider the wider impact of the research to be their keystone is just brilliant.

I love the quote at 17:00:
“We can do absolutely anything here. There are no excuses.”

Adiabatic clusters…

The Pontiff has an interesting preprint here:

Adiabatic Cluster State Quantum Computing

Which suggests that it might be possible to implement gates on a suitable AQC architecture (I wonder where we could find one of those?) by slowly changing the overall Hamiltonian of the system to ‘encode’ gates along the way. Measurement is then only required at the end of the computation at the readout stage. Or at least that’s what I think happens 🙂


Science visualisations

This is very cool:

Bio Visions – Harvard

Check out the video ‘The inner life of the cell’.

I probably learnt more about biology in watching this 8 minute video than I would have done in a whole university module. It’s a great project; we need more like it. It got me thinking about visual learning.

Humans seem to be primarily visual animals, and as such we can learn a lot from watching a good visualisation of something. When I read a text book or try to understand a new concept in Physics, I try to mentally imagine a model of the world. I’m using analogies and manipulations of 3-dimensional abstract objects, but I’m always painting a picture. I wonder if having that picture painted for us can help us learn faster.

One could argue that different people learn by different methods, which I’m sure they do. Some people are audio, textual or mathematical learners. But I feel that the standard, classical lecture-style learning in which we are taught most of science is probably also the most inefficient way of getting the information from A to B (i.e. it resonates strongly with very few learners). I think a visual method may not suit everyone, but it would resonate more strongly with a larger number of learners.

In physics, I’ve seen a few 3d visualisations of solid state phenomena, but they certainly aren’t commonplace. I really think that visualisations can help with understanding some pretty abstract concepts, such as the transition of electrons from a classical ‘wave packet’ or ‘particle’ description to a macroscopic quantum wavefunction during a condensation through the critical temperature. Try explaining that to someone who has never encountered any of the concepts. Now imagine that you could project the little video that you run inside your head everytime you visualise the process, and talk through that instead. I’m pretty sure it would make explaining things a lot easier.

There’s a slightly subtle point here: Does the very building of your OWN internal visualisation of an effect help you to truly understand it? If you were just shown someone else’s idea you might not have shared the same thought process and building of the model to get to the final ‘understanding’ stage. Could it even worsen the situation, rendering you biased against developing your own different yet valid visual interpretation?

Is taking away the extra stage of building a world model through internal visualisation really something that would deprive people of insight and deep understanding? Or would that insight just come about all the more quickly?

I’m surprised that the traditional style of lecturing has perservered for so long. One might have thought that powerful and beautiful visualisations of Physics would have pervaded our attempts at conveying a model of the world to students and colleagues.

I think that two hurdles stand in the way.

1.) Existing teachers and lecturers are not accustomed to using new techniques ‘The way you learnt is the way you teach’.

2.) There is an activation barrier to using these new technlogies because they are pretty hard to get going in the first place.

In a subsequent post I might discuss possible ways in which we can do something about this instead of just going off on a complete brain-ramble which is what I seem to have done here 🙂

Fridge surgery

Take a look at this picture:


Yes I am hacksawing a dilution refrigerator….

One of the entry ports to the IVC has been hardsoldered with a stainless steel placeholder bush. We need to replace this with our custom made copper bush with feedthroughs for coaxes and DC lines. It is virtually impossible to remove this part given the small space around it, and we decided that we don’t want to put power tools nearby, lest we accidentally buzz through the dilution unit. Which would be a bit like putting a scalpel through the jugular.

So hacksaw it is.

I wonder how many low temperature physicists have wanted to saw their dilution fridges in half before. Today I got to indulge in that pleasure. The results weren’t pretty at times:

that's gotta hurt

Although half way through I started thinking ‘I hope that this is the right part I’m sawing…’

The obligatory book post

You all knew it was coming, so here it is:
My art book is now available… which means I’m a published artist, and one step up from a starving artist 🙂

This version is in Spanish, I’m working on getting an English version published but that may take a little while. But the pretty pictures really are the main focus of the book, the text is just an accompaniment, and there are translations available on my website.

I apologise to those readers who have already been inundated with GF paraphernalia.

You can buy the book on Amazon:
Gothic Fall – S Gildert AMAZON

or direct from the publisher (much cheaper):
Gothic Fall – S Gildert NORMA EDITORIAL

A flurry of interesting preprints…

My pick of interesting recent ArXiv papers…
So much to read, so little time!

Robust Entanglement in Anti-ferromagnetic Heisenberg Chains by Single-spin Optimal Control

Quantum System Identification: Hamiltonian Estimation using Spectral and Bayesian Analysis

Hierarchical Genetic Algorithm Approach to Determine Pulse Sequences in NMR

Efficient creation of multipartite entanglement in flux qubits

Spin Systems and Computational Complexity

Algorithmic Technique for Decomposing Unitary Operations in NMR Quantum Computation