May 29, 2016

note290516_01.jpgWe are curious because curiosity gave our ancestors an evolutionary advantage: curious people knew where there were dangers, where to find food, where to find shelter. A curious person held a branch on fire rather than running away from it – not because she or he guessed it could come useful for cooking, for heating, or as a weapon or a source of energy –  but because they were intensely curious about it. It’s our most useful instinct.

Curiosity-led scientific research is the collective embodiment of human curiosity. It is helping us to survive and develop as a species. The moment we stop doing it will be the beginning of the end for our species.

We must fight to enshrine social support for curiosity-driven research. That’s research we do because we want to know, not because we want to achieve something. That’s the type of research that will save our civilisation from global warming, from hurtling meteorites, from dangerous microbes – from everything that, without our curiosity, we would never even have known about.

Nobel Prizes for Physics and Chemistry 2009

October 8, 2009

The Swedish Academy of Sciences has awarded this year’s Nobel prize for Physics to Charles K. Kao for “groundbreaking achievements concerning the transmission of light in fibers for optical communication” and to Willard S. Boyle and George E. Smith for “the invention of an imaging semiconductor circuit—the CCD sensor.” Physics Today offers a brief, and very readable, account of the breakthroughs that deserved this accolade.

In addition, the Nobel prize for chemistry this year has gone to Venkatraman Ramakrishnan, Thomas A. Steitz, and Ada E. Yonath “for studies of the structure and function of the ribosome” in which, as Physics Today points out, X-ray crystallography played a crucial role. Thus their achievement straddles beautifully across the fields of Physics, Chemistry and Biology.

The Nobel Prizes serve a dual purpose: on the one hand, they are an opportunity that the scientific community has to honor and reward those that have made the most important contributions. On the other hand, they represent the chance to send a message to the rest of society. Let us hope that these prizes will remind decision-makers and the public everywhere of, firstly, the crucial role that today’s research plays in creating tomorrow’s technologies and, secondly, that all fields of science are strongly inter-dependent, so it is not profitable to cherry-pick individual areas for support while others are neglected.

Are robots the next condensed matter?

September 23, 2009
Modular robots on the march... Is this the next condensed matter?

Modular robots on the march... Is this the next condensed matter?

Because condensed matter deals with concepts as fundamental as as scale invariance and broken symmetry, it is sometimes hard to predict where the next big condensed matter physics problem will turn up. For example (continuing from my latest post) who would have guessed twenty years ago that atomic physicists and high-energy physicists would today be furnishing some of the most interesting examples of strongly correlated matter? So it is interesting to be wild and speculate where the next big realm of condensed matter physics may lay. (After all, wild speculation is one of the things a blog may be useful for.)

In this spirit, I dare suggesting a look at modular reconfigurable robotics: robots made up of many individual, but interacting, identical elements. There are a number of groups around the world working on it. At the time of writing, there is a fairly detailed overview of the field on Wikipedia.

The Wikipedia article list a number of challenges for the future. It starts with the following (I quote):

Demonstration of a system with >1000 units. Physical demonstration of such a system will inevitably require rethinking key hardware and algorithmic issues, as well as handling noise and error.

A way to phrase this problem is to say that we want a large assembly of robots to behave like a condensed matter system, where a very large collection of individual, interacting elements (e.g. all the individual atoms in a magnetic material) conspire to produce a collective behaviour (e.g. ferromagnetism) in spit of the presence of errors and imperfections (e.g. impurities, missing atoms at indivudal lattice sites, and so on). So in some sense this problem of modular reconfigurable robotics has already been solved by Nature in condensed matter systems. Thus some important problems in modular reconfigurable robotics might be solved by looking to condensed matter for inspiration (e.g. find the conditions to achieve in the robots the equivalent of generalised rigidity).

Indeed researchers in that field are already having to draw on some elementary condensed matter concepts. See, for example, the PARC Modular Robotics website: the section on the Proteo project even has a good old-fashioned discussion of close packing structures.

Conversely, and perhaps even more interestingly (at least from a condensed matter theorist’s point of view) the robots could be used to realize new states of classical condensed matter – just as novel forms of quantum condensed matter are currently being created through chemical synthesis and in ultra-cold atom labs. Interestingly, the individual building blocks in the case of robots can be a lot more complex than in any form of condensed matter we currently know of e.g. the rules governing element-element interactions may be very complicated – for example, the interactions could be time-dependent or depend on the history of previous interactions for each individual particle (i.e. each individual robot module). It will be interesting to see whether such complexity of the individual particles will find a manifestation at the collective (macro) level or rather we will find that the beahviour of the whole always obeys simpler, emergent organisational principles. The latter is the case of, for example, a human crowd – though the interactions between individual components of a human crowd are in fact simple, while in the case of robots we might engineer them to be very complex.

Micro Cryogenic Coolers (MCC)

April 14, 2009

A lot of the really interesting phenomena in Condensed Matter Physics only take place at very low temperatures, e.g. superconductivity. This often limits their usefulness, as cryogenic equipment (necessary to achieve such low temperatures) is costly and bulky. THz switching using superocnductors is great for some very specialised applications, but it is not going to give us desktop computers operating at THz speed (=1000 GHz) if that requires the computer in question to be permanently connected to a tank of liquid Helium. But what if every chip had its own, micron-sized cooling devices, so that only the microscopic circuitry itself were at such low temperatures? DARPA believe that such microcryocooling technologies are worth pursuing, and we agree (though for very different reasons!)