Faster than light, ha!

Here is the latest on the Opera experiment, the one which claimed to have found neutrinos which moved faster than light, and reached Gran Sasso 60 nanoseconds faster than photons would have. `Sources' claim the discrepancy comes from a bad connection between a fibre optics connection with a GPS receiver which was used for the time of flight measurements. There's also a glitch in the oscillator which times the intervals between which the system is synchronised. Although the two glitches are claimed to work in opposite directions in estimating the apparent speed, it is clear that further work and independent measurements are needed to finally close this issue.

Tailpiece: The neutrino and the photon came face to face.
Photon: So, that Bolt was a false start.
Neutrino: It wasn't my fault, it was the cable's!

This blog post is by Neelima Gupte and Sumathi Rao.

Cricket, anyone?

The cricket season is on with its ups and down, test matches and ODI-s and inflation and deflation of rankings and reputations. Diehard fans, as well as occasional TV watchers wait for Sachin's 100th century, weep for the whitewash in Australia and wonder how things could go so wrong! Let's see what light a bit of quantitative analysis can shed on these events. The ICC rankings, opaque as they are, attempt to quantify the nonquantifiable, the crack of the bat on the ball. A recent paper attempts to do the same, using the techniques of network science, treating the cricket playing nations as a social network. The teams are ranked, depending on their success in test cricket, and one day cricket, for all the years for which the data is available, (1877 onwards, no less), and so are the team captains. The success of a team (or captain) is determined by the ‘quality’ of wins and not on the number of wins alone.

The method consists of forming a weighted network. All competing teams form the nodes of the network. If team A defeats team B, a link is established pointing from B to a A with a thickness (the weight), proportional to the fraction of wins where B wins against A. The importance of the match is assigned via a quantity called the PageRank which uses the normalised weight of the link in a diffusive term which redistributes the credit of a given node to all its neighbours, with maximum credit being transferred to its most successful nemesis. Teams are then ranked by their PageRank, and captains are as successful as their teams.

The results conform to common intuition, which the ICC rankings don't always do. Needless to say, Australia emerges as the strongest test playing nation, followed by South Africa, despite their twenty one year absence from test cricket (1970-1991), England, West Indies, Pakistan, India, Sri Lanka, New Zealand, Zimbabwe and Bangladesh. Since this is an average from 1877, it is unsurprising that this is more or less the order in which the teams started playing test cricket, except for South Africa. For ODI-s, the order is the same, except for Sri Lanka and New Zealand exchanging places. The most successful test captain is Australia's Steve Waugh, followed by South Africa's Graeme Smith, and Australia's Ricky Ponting. From the subcontinent, only M. S. Dhoni and Sourav Ganguly make it to the top 20 list. For ODI-s, Ricky Ponting leads the table, followed by Graeme Smith and Imran Khan of Pakistan. M.S. Dhoni, Kapil Dev, Saurav Ganguly, Mohammed Azharuddin, Rahul Dravid, Javed Miandad, and Wasim Akram also make it to the top 20 list, perhaps indicating that the subcontinent is better at the shorter version of the game. PageRanks computed over successive decades pick up the domainance of the successful teams of those decades, such as the West Indies dominance of both tests and ODI-s from 1981-1990, India's success against strong teams between 1971-1980 (not reflected in the IIC rankings), and the rise and fall of teams like England, Pakistan and Australia in the pecking order. The author (Satyam Mukherjee at Northwestern University, formerly at IIT Madras), modestly says that this scheme cannot replace the ICC ranking, but suggests a novel approach to refine the existing ranking scheme. We hope this scheme will find its way to the cricket commentaries.

This blog post is by Neelima Gupte and Sumathi Rao.

The original paper can be found here .

Now where were those keys?

This week sees the news of an important breakthrough in the study of degenerative brain diseases such as Alzheimer's and Parkinson's diseases.While it has been known that the diseases spread due to the spread of a distorted protein, (the tau protein for Alzheimer's ), outward from an area where memories are made and stored, the mechanism of spread was not clear. There were two possible mechanisms proposed for the spread. One, that the spread could take place from neuron to neuron, along neuronal pathways, and the other that there were neighbourhoods that were susceptible to the bad protein, and others that could resist it. It is now established that the spread takes place along neuronal pathways.

The experiments that establish this mechanism are ingenious, and involve genetically engineered mice that can create the human tau protein in a localised area called the entorhinal cortex. Cells in the entorhinal cortex of the mice started dying due to the tau protein. In due course, the disease spread to other areas via the neuronal network. Since other cells could not make the tau protein themselves, the only way the tau could show up in other areas was via transmission from nerve cell to nerve cell. It may then be possible to halt the diseases by preventing cell to cell transmission, e.g. by blocking the tau with an antibody. This might provide the key to the prevention of degenerative nerve diseases (and help find those elusive keys!).

This blog post is by Neelima Gupte and Sumathi Rao.

Presidency University

The high point of last week was a visit to the oldest college in India. Presidency college, Kolkata, started life as Hindu college and was founded by Raja Ram Mohan Roy in 1817. In 1855, it was renamed as Presidency college, and has metamorphosed into what might be the youngest university in India, Presidency University, in 2010. Before this, the college was affiliated to the University of Calcutta, since 1857. The college shifted premises several times until it came to rest at its present location on College street in 1874, across the road from Calcutta University. The chemistry department conducted its first batch of practicals here in the next year, starting the venerable tradition of science departments, which train what turn out to be the best science students in the country, year after year, right upto now. Here is a picture of what the "new building" looked like last week.

You can see from the banners and the bunting in the photos that the college is presently conducting student elections, as well as the 41st reunion of the geophysical society. Over its life span, the college has boasted of a veritable galaxy of stellar teachers, J.C. Bose, and P.C. Ray being among the most notable. Here is a picture of the statue of J.C. Bose, sitting in the marble corridor outside the J.C. Bose auditorium, looking a trifle bad tempered. That's probably the black granite!

The college has now to negotiate the tricky path which will take it from its position as one of the most renowned colleges in India, to graduating to a full fledged university. It has a host of distinguished ex-students who will perhaps be only too happy to help along their alma mater in this endeavour, to say nothing of the good wishes of all of us, who have been sufficiently fortunate to have acquired numerous friends, and all our best students, from its alumni.

This blog post is by Neelima Gupte and Sumathi Rao.

The new year

When the new year
came out of nowhere
and peeped into rooms
it was so flattered to find
all the tv's drinking its health
praising its innocent appearance
it responded with its warm
dark smile and went round
filling peoples dry hearts with joy

Rg Gregory, `When the new year', Young World, The Hindu, 03/01/12.

This blog post by Neelima Gupte and Sumathi Rao.

The Higgs at last?

So 2011 runs out, and Europe and North America have shut down for the holiday season. Before CERN, its physicists and staff all left to make merry over Christmas and the new year, they called a press conference to tell us whether Santa had indeed visited CERN this year, and left a Higgs boson in their stocking. The upshot is that although it's too early to break out the champagne, it would not be unwise to place orders for next year.

The press conference announced that both the Atlas and the CMS experiments at CERN have seen signatures of the Higgs at a mass about 125 GeV. While the statistical significance of the data exceeds 2 sigma, it has not reached the 5 sigma level at which a new particle is announced (hence the postponement of the bubbly). However it is noteworthy that the signature of the Higgs is seen in both experiments, in two different decay modes ( Higgs to two photons, and Higgs to four leptons via Z, Zbar) and at essentially the same mass. It is also important that the Higgs boson which is seen is consistent with the standard model, but is seen at a mass which does not rule out supersymmetry. Santa may break out the goodies for our supersymmetric friends, next year, after all. It will be worth the wait.

On the flip side, this will have been the slowest Eureka ever.(The top quark was like this, but every pimple on the distributions wasn't under world-wide discussion instantly, those days). On the other hand, do we really want to see 3000 physicists jump out of their bath tubs in the altogether? The Armani suits (or whatever, we're no experts) of the webcast were better. That was also the slowest webcast ever, but we won't spoil the holiday season by complaining.

Merry Christmas, everyone.

This blog post is by Neelima Gupte and Sumathi Rao.

The Arab winter, breaking dawn in Myanmar, and what of back home?

The Arab spring has given way to the winter of discontent, especially in Egypt. The military which looked like a resonable interim solution after Hosni Mubarak's forced departure, had to be forced into vacating the central space occupied by them. Meanwhile, the elections have given an alarming fraction of the vote to not just middle of the road Islamists, but to ultra-conservative parties. Die-hard optimists are still hopeful that secular elements will win the day, but a period with Egyptian versions of Khomeini might turn out to be inevitable. Well, who said democracy was an easy solution?

On a brighter note, the military junta seems to be loosening its hold on Myanmar. The charismatic Aung San Suu Kyi is contesting the elections with her National League of Democracy party, and, incidentally, exchanging bright smiles with Hillary Clinton. Cynics claim all this is in aid of Myanmar's pursuit of the Asean chair, and will soon be turned off since this objective is now achieved. However, as all despots from Saddam to Mubarak have had to notice, it's not so easy to put the genie back in the bottle.

Meanwhile, back home, the Indian government seems to be trying to do just that. The idea of trying to have guidelines for web-content is not bad in itself, but surely it is better to have this administered by a self-regulatory body? A Web Council of India, like the Press Council of India, seems to be a better idea than the government getting into the act. That might be as self-defeating as the government trying to run an airline. Is anyone listening?

This blog post is by Neelima Gupte and Sumathi Rao.