Tuesday, July 5, 2016

Juno and Jupiter

Juno's reached Jupiter, and is in a Jupiter orbit, as everyone with a news feed knows! Nasa's spacecraft  Juno has a very intensive scientific programme planned, including an investigation into the unusual stability of the solar system's biggest coherent structure, the famed red spot of Jupiter. More updates as information trickles in.  Meanwhile, a picture of the red spot from an old friend.

A picture of the little red spot of Jupiter by New Horizons, taken when it flew by Jupiter in 2007.

This blog post by Neelima Gupte and Sumathi Rao.

Sunday, June 12, 2016

Hill station holiday

Last month was the right month to head for the hills, and escape the oppressive heat of the plains.
There's of course no way of escaping the jostling crowds at New Delhi's T3 terminal, except via the jostling crowds at New Delhi Railway station. However, everyone else is also in a good mood, since they are  escaping to the hills, too. In fact, everyone is in such a good mood that Air India staff escapes being slaughtered, even after announcing that the flight to Kullu is cancelled, and there is no other flight till the next day. (Passengers look murderous, Jet Airways staff looks smug, but there is no riot). On to Chandigarh, (no, no cancellation), and out into the heat of the afternoon, a reminder that we are still in the plains.

An early start to Chail, up the hill road, in a rickety bus. The perfectly good two lane road of ten years ago, is in the process of being expanded into a four lane highway, and is currently a nightmare, with bulldozers, excavated hill sides, and invitations to land slides. The valiant bus crawls its way clinging precariously to the side of the road. The driver is brilliant. Various faces turn green and water bottles are passed around to quieten queasy stomachs. One tea stop and sundry jacaranda trees later, the rain starts. Various cheerful stories also start, e.g. of people who left for Shimla, sixty kilometres away, on a day like this, and were rescued by helicopter fourteen days later. The bus slows to a crawl, but we end up safely at Chail's palace hotel, merely a little damp due to the rain inside and outside the bus. Chail was the summer capital of the Maharaja of Patiala, who was kicked out of Shimla by the Viceroy for his hell raising antics, and built Chail Palace in a huff.

Chail palace is charming, with huge rooms, antique furniture, log huts and an annexe and a pine forest all around. It's unlikely that the pictures are the  Maharaja's pictures. (The death of Socrates?)
They also throw in a few monkeys.

The lights of Shimla can be seen across the hill.

There's a pretty little garden. The village is a one road village, but there is a stadium, a military school, and a Kali Mandir with a spectacular sunset, an unexpected view of the snowline, and, guess what, solar panels. A few days here, is a few days out of time, out of the hassles of day to day existence, until it is time to go back.

This blog post is by Neelima Gupte and Sumathi Rao.

Tailpiece: Day to day hassles? What do you mean day to day hassles? See below.

Self: How can you lose my bag on a Chandigarh Delhi flight?
JA:  Not to worry, we already sent it to Chennai.
Self:  But I'm here in Delhi.
JA:  Not to worry, we will get it back.

Not to worry, they did. Took time, though!

Friday, June 3, 2016

A planetoid called Pluto

Our favourite planetoid Pluto is in the news again. The United States Postal Service has released two beautiful stamps showing the eternal pair, the New Horizon space craft, and one of its wonderful  pictures of Pluto, in fact every one's Valentine picture of Pluto, with the heart shaped region, the Sputnik Planum,  featuring prominently.

The USPS has added to the bonanza by releasing a set of 8 stamps each one with its own planetary member of the solar system.  Pluto, which got bounced from its status as a planet, and demoted to being a dwarf planet, a while ago, has been consoled by giving it its own stamp, together with that of its intrepid explorer.

Neither planets nor planetoids have ever looked more gorgeous, albeit thanks to digital enhancement. Now that NASA and USPS have done their bit, we look forward to our own pair, ISRO and India Posts, to give us our own set of stamps from ISRO's space explorations.

This blog post is by Neelima Gupte and Sumathi Rao.

Friday, April 22, 2016

JNU/HCU/IIT and all that

This post is a bit late. On the other hand it is perhaps better to wait till the dust has settled down to write on controversial topics. The last six months have witnessed turmoil on several academic campuses, with strong similarities between the incidents that occurred on each one.

The saddest case occurred on the Hyderabad University campus,with a  tragic culmination in  the suicide of the young and promising Dalit student, Rohith Vemula. What started as a simple case of a scuffle between two student groups, and the consequent rustication of one student group, went out of hand due to mishandling and political interference, and resulted in the loss of a young life. Subsequent events were even more bizarre, with reports of vandalism on campus, the entry of the police,  the arrests of students and faculty, and verbal and physical violence towards protesting students.

The story at Jawaharlal Nehru University involved `anti-national' slogans raised at a student event involving Kashmiri students, the arrest of Kanhaiya Kumar, the president of the student union, subsequent attacks on him at the courts, and the hunt for  those who were actually involved in the incident, who may or may not have been the students finally identified as the culprits.

The incidents at IIT were milder, as befits its sober and nerdy image. Arguments between  students belonging to two student societies, resulted in the withdrawal of recognition  to one of the concerned parties, allegations and denials of political interference,  and the subsequent restoration of the status quo, albeit with more restrictions on the organisations than existed  before.

What is startling is the similarity between the incidents on widely separated campuses, which could have been handled peacefully within the rules of the academic institutions, provided they had been applied with some vision and concern, and the opportunity they provided for outside interference. Even more startling is the reaction of the general public, which  includes berating students for taking interest in societal and political issues, questioning their academic and familial credentials, and even going to the extreme of estimating the cost of their student stipends and recommending that they start `earning their living' and stop being `a burden on society'.

 There are several broad issues involved here, and many of these have already been discussed threadbare in public fora. We would only like to focus on one here. Universities and academic institutions are meant to be places where notions of society, state and culture are discussed, and to provide platforms for opposing points of view. The norms and regulations of academic institutions are supposed to have evolved to a point where differences of opinion can be sorted out in a democratic, orderly and peaceful manner. It will be  best if politicians and the public allow them to do so.

This blog post is by Neelima Gupte and Sumathi Rao.     

Saturday, March 5, 2016

Rahul Basu 04/03/1956-05/03/2011

May the road rise up to meet you,
may the wind be ever at your back.
May the sun shine warm upon your face,
and the rain fall softly on your fields.
And until we meet again,
may God hold you in the hollow of his hand.

An Irish blessing. 

This blog post by Neelima Gupte and Sumathi Rao.

Wednesday, February 10, 2016

Gravitational waves

Has the LIGO observatory observed gravitational waves? Rumours have been rife that LIGO (Laser Interference Gravitational Wave observatory) has picked up the signature of gravitational waves   (ripples in space time) arising from a massive cosmic event, the collision of two black holes. Astronomers have been looking for confirmation of the rumoured LIGO events  in the form of an optical flash in three parts of the sky, in the constellation Dorado, as well as in the constellations Aries and Hydra. The last time the classic signature (a `chirp') was observed in the LIGO data was in 2010, but it was announced to be a false signal, fake data inserted to ensure that the analysis could, in fact detect a signal. The experiment has scheduled a press conference on 11th February, where they may confirm the observation, (or not!).  More tomorrow,  the entire physics world waits with bated breath. Hopefully, the LIGO spokespersons will not shout April Fool, in February!

 Update: February 12th:

They did find it. We had the unique experience of hearing the universe chirp, that too on our mobiles (the quality of the broadcast was absolutely wonderful!). Gabriela Gonzales provided the details. Two massive black holes of solar masses 36 and 29 coalesced to form an object of 62 times the solar mass. Their motion, which spiralled round each other, before the collapse (250  revolutions per second at half the speed of light) provided the chirp. This event occurred a billion light years ago, at a time when life on earth had barely progressed to multicellular organisms, at a location roughly in the direction of the Magellanic cloud. The observation was a triumph of state of the art experimental technique and technology, the mirrors of the interferometer moved through a distance of 4/1000ths of the diameter of the proton due to the effect of the wave. As far as the theory is concerned, the original prediction dates back to Einstein in 1916, and Taylor and Hulse had made an indirect observation of the gravitational waves which would have been obtained due to two neutron stars spiralling inwards coalescence. Taylor and Hulse got the Nobel for their discovery. So who is in line this time? The three originators of LIGO were Kip Thorne,  Rainer Weiss and Ronald Drever, and of course,  there are now younger collaborators. The Bicep2 team must be sad at having missed the first detection, although they may still get the first wave from the big bang. The result is also a vindication of big science. The National Science Foundation spent $1.1 billion over the LIGO detectors at  Livingston, Louisiana and Hanford, Washington over 40 years, including the recent upgrade to the Advanced LIGO lab, which finally bought the detectors to the stage where the recent detection became possible.  The result came almost immediately after the upgrade, last September, just after the calibration of the advanced LIGO system. The result is a collaboration between these two LIGO Labs and the Virgo observatory in Europe.  There are three more events in the pipeline, which are currently under analysis. Two more LIGO labs are proposed, one in Japan, and one in India, where they will hopefully find adequate funding support and ecological blessing from all concerned parties! These are exciting times to be in physics. These discoveries are invitations on the part of the discipline to join the excitement.

This blog post by Neelima Gupte and Sumathi Rao.

Postscript: The original paper has appeared in Physical Review letters yesterday. It's great to see a Chennai institute, Chennai Mathematical Institute, Chennai in the affiliation list of the authors.

 What did the blackbird say to the black holes?  `And a chirp to you, too'.

Update 16/06/16

A second gravitational wave event has been detected, again from the coalescence of two black holes, somewhat smaller than the ones which collided in the first event. This second event was a Christmas gift from the universe to us. The data analysis took six months, which is why the event was only announced last week. As for the details, one can't do better than quote  the succinct Physical Review Letters abstract, reproduced below. So here you are, error bars and all.

'We report the observation of a gravitational-wave signal produced by the coalescence of two stellar-mass black holes. The signal, GW151226, was observed by the twin detectors of the Laser Interferometer Gravitational-Wave Observatory (LIGO) on December 26, 2015 at 03:38:53 UTC. The signal was initially identified within 70 s by an online matched-filter search targeting binary coalescences. Subsequent off-line analyses recovered GW151226 with a network signal-to-noise ratio of 13 and a significance greater than 5σ. The signal persisted in the LIGO frequency band for approximately 1 s, increasing in frequency and amplitude over about 55 cycles from 35 to 450 Hz, and reached a peak gravitational strain of 3.4+0.70.9×1022. The inferred source-frame initial black hole masses are 14.2+8.33.7M and 7.5+2.32.3M, and the final black hole mass is 20.8+6.11.7M. We find that at least one of the component black holes has spin greater than 0.2. This source is located at a luminosity distance of 440+180190Mpc corresponding to a redshift of 0.09+0.030.04. All uncertainties define a 90% credible interval. This second gravitational-wave observation provides improved constraints on stellar populations and on deviations from general relativity.'

Saturday, December 26, 2015

A humongous Higgs?

Last week's blogs and websites have been atwitter with news of what could be a new Higgs boson. Both the ATLAS and CMS collaborations have seen `a bump in the data' at 750 GeV. Both collaborations have been seeing that proton-proton collisions that result in an unexpected number of di-photon pairs, pairs of photons which together carry away about 750 GeV of energy. This could be a new Higgslike boson, but 6 times more massive than the Higgs boson of the Standard model discovered in 2012. The statistics are nowhere near a level at which, anyone can claim an actual discovery, nor have the spokesmen of either collaboration done so. Atlas has discovered about 40 more pairs of photons, than what is predicted by the Standard model, and CMS has found just 10. However, it is intriguing that two independent experiments have found the photons at exactly identical energies. It could be a hulking Higgs after all! Of course, this could all vanish away into nothing. Watch this space for further updates.

Tailpiece: What did the HB say to the HHB ? You may be incredible, but I am Noble.

This blog post by Neelima Gupte and Sumathi Rao.