Friday, November 28, 2008

11-26 Mumbai...

Mumbai..the commercial hub of India is targeted once again. In India terrorist attacks have become a part of daily life for the civilians. They face it one day..forget the other day. I dont even feel like posting these never-ending tragedy in India. We witness such events at least once in a month. Its hardly one month after the blast in Guwahati which took around 90 lives, yesterday it happened again. As alwys been a soft target for terrorist Mumbai became a victim once again. But this time they attacked with a new and never seen strategy. It was not just blasts as happened before , there were indiscriminate firing in public places like railway stations, hospitals, hotels etc which finally lead to a hostage situation. They captured hundreds of people (some of them are foreign nationals) in hotel Taj, Oberoi Trident and in Nariman House, made them hostages. Sources say they were looking for specifically US and UK citizens. Although the situation seems under control now after 24 hours of gunbattle,panic across several places I hope the lessons learnt wont be forgotten. I wont start a blame game here but the way the terrorists entered Mumbai yesterday( through the coastal areas, they reportedly came by a boat loaded with weapons) was similar to the situation in 1993 when Mumbai( then Bombay) was shattered with serial blasts. May the souls of those killed (125 so far) rest in peace and those who were injured get well soon. I am hopeful of full fledged normalcy by tomorrow across Mumbai...

Saturday, November 22, 2008

LHC & the end of the world....

After all the unnecessary panic regarding the end of world stuffs after the protons start colliding at LHC, I have read a brief essay by Michael Peskin (SLAC) where he talks about how this dire possibility can be ruled out both theoretically as well as experimentally. He talks about the paper Physical Review D 78, 035009 where Steven Giddings(UCSB) and Michelangelo Mangano(CERN) have argued with explicit calculations that if LHC can produce such a black hole which can swallow the earth these kind of events would have astrophysical consequences in the past Universe. But we dont see any well known astrophysical objects swallowed by such dangerous black holes.
Peskin also points out the fact that although we keep on saying that any micro blackholes if produced in CERN would evaporate almost instantaneously by Hawking Radiation, there is no experimental evidence of Hawking Radiation so far. But the theoretical arguments behind Hawking radiation is so strong that we can't rule it out. Although there is a model by Unruh where black holes do not radiate, it is also constrained by the fact that it happens only at the cost of violating Lorentz invariance which can happen only at the Planck scale. Thus LHC which operates in TeV scale( 16 orders of magnitude below the Planck scale) is safe enough from these dangerous circumstances.
Peskin says,"If we ignore these strong theoretical arguments we could pursue another path. Huge numbers of high-energy cosmic rays have hit the earth over its lifetime. Thus we an argue, nature has already carried out the LHC experiments many times. If we are still here, the LHC must be safe."
He also talks about some scenerios where these arguments are insufficient. There are some "slippery" black holes which arise in the extra dimensional models which may creat a genunie problem. But in the paper mentioned above the authors have addressed this problem as well. You can at least see the Peskin's review article which doesnt need any subscription from Physical Review. The link is
http://physics.aps.org/articles/v1/14

Thursday, November 20, 2008

Screwd Up...

..After going through the painful calculations of the masses of the scalar Higgs fields in the SUSY LR model suddenly I got to know that all these are going to be of no use. Damn it!!!The SUSY LR model contains a total of six triplets and two bidoublet and hence fifty two real scalar fields. It was damn painful to do the calculations starting with the D and F term scalar potentials. I thought this to be a good work..but suddenly my supervisor came and told me these scalars are too heavy and not a suitable dark matter candidate...oopss!!now I need to look at the neutral fermionic sector...Hope something works out...

Friday, November 7, 2008

LHC delay..

Its a pretty old news that LHC(Large Hadron Collider) has been delayed by approximately 6-8 months which is now scheduled to restart next year (probably in May or June). Its due to some superconducting magnet failure whose details CERN has already released here : http://press.web.cern.ch/press/PressReleases/Releases2008/PR14.08E.html
One of our department Prof (in IIT Bombay) who specializes in experimental condensed matter physics( specially magnetism) was chatting with one of my friend here regarding this incident. He said that those magnets were sent by India to the CERN and it was the faulty welding between two such magnets which caused the incident.Well whatever it is what happened was really unfortunate.
Just like there were lots of rumours(e.g. Big-Bang,Black Hole etc etc) just before the start-up of LHC on 10th Sep 2008, similar is the case after it has stopped. One of my friend (non-HEP PhD student ;)) told me she heard somewhere that the whole system of the LHC was hacked by someone who were opposing such too costly as well as fatal(?) experiments.I have seen such incidents in many crappy hollywood movies where the whole US govt netwrok is hacked by some and bla bla...Anyway although sucn comments,views are irritating most of the times...they sound funny to me sometimes. I remember one incident when the whole media were shouting the possible collapse of the whole earth after the LHC gets turned on etc etc...one person from my village...(well its a village where people hardly know anything about particle physics, LHC, Black-Hole, Big-Bang etc)..called me up to say "Good-Bye"..because he was pretty confident that the very next day everything would be over..somehow which he did not bother about.I was laughing like hell at it..it was so funny..at the same time I wanted to kick the ass of those media who has put these stupid things, fears in the minds of common people.Then I assured him that nothing of this kind gonna happen..so theres no need to worry about. :P
Anyway hope LHC would start working soon and let us zoom closer and closer into the nature to reveal her secrets....

Saturday, November 1, 2008

Post-Diwali Blast@Guwahati

30th October 2008...People in India were busy with their scheduled works after the diwali vacation. The same was true for the people in Guwahati(the capital city of Assam) also. Nobody could even imagine that something was going to happen that day in their beloved city which no one ever witnessed. Yes your guess is correct; I am talking about the 10-30 blast in Assam which took at least 100 lives leaving more than 500 injured.Guwahati suffered the most including other places in Assam like Kokrajhar, Barpeta Road, Bongaingaon. In all the places the blasts occurred within half an hour if I am not wrong. Although people in a disturbed, fear-filled state like Assam are used to the incidents like bomb blast along with many such horrible things yet the recent blasts were the most powerful as well as most tragic. According to my friend when the blast occurred in Ganeshguri area near the car parking the 10 auto rickshaws standing there started burning simultaneously along with other vehicles. The flyover also got a big hole in it. The intensity was so high that many of the victims' dead bodies were just a mixture of ashes, bones, teeth etc. One person from my district in Assam has been identified as a victim with some bones, teeth found on the spot and a gold ring which he used to wear. Its extremely horrible. I dont care or dont wanna say anything regarding who are behind blasts as classification of terrorists doesnt save the common people from these heinous activities. These kinds of problems are not new in India. People in India have been witnessing these since years. But due to various reasons which I dont know no strict actions seem to be taken. At this point I can give one example. In the last six months according to the report there were 87 blasts in India. And Intelligence report says in many of those blasts (including those in Assam) some Bangladesh based Islamic outfits are behind. In spite of this our Government never tries to take action against crores of illegal Bangladeshis most of whom are in North-East. It has been warned a number of times how these illegal migrant may change the entire demography of the country etc. But due to vote bank policies of the Government nothing has been done till now.
Its interesting to mention that India is one of the fastest growing economy in the world, it has recently signed the 123 Agreement with the US which allows India to buy Nuke Fuels from NSG for civilian purposes, India has recently successfully launched its lunar exploration satellite Chandrayaan I into the space..and many more good things. I know these good things happening in our country keep those shitty things like bomb blasts etc out of the focus most of the time. Everytime a bomb blast occurs, many people die and from the next day people forget about it and get busy with their daily lives.They have no other options as they have to get back to their work for their survival. But if strict actions are not taken by the Government regarding these Islamic outfits operating inside the territory the time is not very far when their joint operation throughout the country will make our country collapse.

Wednesday, October 29, 2008

SERC Preparatory School in THEP'2008

Recently I went to participate in the SERC preparatory school in Theoretical High Energy Physics(THEP) organised by SGTB Khalsa College (University of Delhi) from 23rd Sep to 20th Oct' 2008. Details about the school is given here
http://sgtbkhalsa.du.ac.in/serc.htm
It was an awesome experience to be a part of it. Specially the course on QFT by Palash Pal(SINP) and Amitabha Lahiri(SNBNCBS) was mind-blowing. Unfortunately they did not give any soft-copy of their notes which I could share with. Secondly the course on Particle Physics and Standard Model by Anindya Datta(CU) and Rahul Basu(IMSc) was also of much benefit as far as Phenomenology is concerned. They taught from a proper phenomenology point of view which was definitely of my as well as many other's interest. Prof Datta had severe cough/throat problems during the school. Surprisingly he did not even use the loudspeaker. So there was "basically" no chance of relief. During his last two lectures which were a bit boring ( it was about the parton model) many of us were busy conducting some experiments inside the classroom. Me and Sushant were counting how many times Prof Datta had to cough during his one and a half hour class. The result we arrived at was 348(+/-5) times in one and a half hour. This is a damn big figure. I wanted to warn him regarding this and to request him to take proper care..but unfortunately I could not dare to do that. Some other guys counted how many times he used the word "basically" in the class. They arrived at some figures which we found very difficult to accept. We also counted how many times he used the word "however" and arrived at 58(+/-3.5) in one and a half an hour. It was real fun to do these experiments at the time when the world is busy in doing experiments like LHC, RHIC etc...
Apart from the courses and the profs the students were really cool( upto some good tolerable approximations) and I really had a very good time with them. People like Sudhanwa Patra(PRL), Kaushik(Mysore Univ), Debraj(SNBNCBS), Arun, Prakhar (BHU),Shruti, Sandhya, Pooja(DU) among others were truly fun-loving. Although Pooja turned dangerous sometimes but finally there was not much problem..she got back her "coolness" finally. I should not forget Dr Mamta (the Director of the school) who was so caring and cool. Apart from that she was the most beautiful lady in the SERC school( as Kaushik bravely mentioned that in front of her). Patra was the most popular student there. He became famous after many funny incidents happened to him which I have to skip here.He was a real genius in QFT and a passionate guy about calculating scattering cross sections of various processes.Even Profs e.g. Rahul Basu and Anjan Sen made fun out of him.It was really amazing...
I am missing those people now a lot. Hope to see you guys again....Rock On!!

Physics as a Profession

I have no idea how far I would be able to go by opting research in physics as my profession. But the important thing is that life is really peaceful now. I know tough days are ahead. Its just the starting of my research career. I happens very rarely that people get a chance to work with some coolmax Prof like my supervisor is. I am working with him for almost two years. Starting with Friedmann cosmology, I have learned QFT, standard model of particle physics, Left-Right Symmetric Model(LRSM) , Supersymmetry(SUSY) basics as well as different SUSY models under him. Currently I am working on the SUSY left-right model and its collider/cosmological signatures. This model is basically an extension of the Standard Model where we incorporate two extra symmetries: Left-Right Symmetry and Supersymmetry. Details of the work will be posted later...

My Life : A Chaotic Journey

I know the time is yet to come when I will be able to write something about my life. Still a long way to go. Being confused about what to post I thought lets start something very personal..my journey till date. It was started at Bogajon Satra, a village in Assam, India. The flowchart along the direction of time would be like
Bogajon-->Guwahati-->New Delhi-->Mumbai-->Munich-->Mumbai
I would like to call various points in my life as genuine phase transitions. The place where I was born people were not literate enough to know what IIT(Indian Institute of Technology)'s are, what Scientific Research is etc etc. Rather they always appreciated power and money. Naturally it also went into my mind. Whenever people asked me what my aim was (or is!!!) I replied instantaneously "Deputy Commissioner". People really appreciated that. At the same time I also knew one thing that Physics and Mathematics are the two subjects which were most fascinating for me although I was unaware of the fact that people can build their career with such subjects only. Then I thought I would do BSc with Physics/Mathematics and then would appear Civil Service examination.
After finishing my class X, I came to Guwahati (the capital city of Assam) to pursue my XI-XII.There I got to know about institutes like IIT, IIM etc. and realized that there are lots of things as well as institutes. Although due to financial problem I could not take some good coaching for the IIT-JEE'2003 still I gave it an unsuccessful attempt. I wanted to get admitted into the Integrated MSc course in Physics in IITK. But after the failure in JEE, I went to New Delhi and joined the BSc programme in Physics (University of Delhi).I spent my days there with people from Bihar as well as UP and naturally got more motivated towards Civil Services examination as you may know Students from Bihar, UP in Delhi mostly prepare for Civil Services.But at the same time I knew that I was losing interst in the kinds of life a civil-servant has to live..something like very busy, tensed, disciplined etc etc. More importantly the bloody politicians politicize the civil servants in such a way that they have to tune into the frequency set by the politicians.These were very unacceptable for me.But since my family always insisted me in doing that I somehow made up my mind to do it.But after I came to IIT Bombay to pursue my Post-Graduation somehow I completely lost my interests in those civil-services etc etc.Life in academics seems the most peaceful for me now. I feel as if I would be a student throughout my life. I know how good it feels to be a student...& now I knw how better it feels when we come to know that the remaining life will not be anything different(upto first order approximations) from a student life.
During my stay in Delhi I used to travel by 2nd class railway compartment whenever I ran out of money or did not get reservations in sleeper class. It was horrible to travel for 38 hours by 2nd class Indian Railway. I went like this three times from New Delhi to Guwahati. If you have ever seen people trying to board in the 2nd class compartment you would certainly realize how brave I was to go like this..:P
And luckily enough few months back I got an opportunity to travel by international airlines like AIR FRANCE when I went to Germany for 3 months. I was visiting Max Planck Institute for Astrophysics,Garching. I had an unbelievable experience out there. Specially for the people in my village I became like an "ideal" . For the people who never saw a railway station traveling by airlines is something really big. Anyway when I went to my home after coming back from Europe most of my childhood friends who are now rickshaw driver, shop owner, some educated but unemployed like most people came to know my experience. I cant say how I felt at that moment. I know its difficult to adjust with so different kinds of people at a time; people from Europe, Bombay, Delhi & then from my village. But somehow I manage to handle this...I miss them so much.I hope I would be able to remain as good as before to all of my friends and siblings.
Its 3 years now in Bombay and noting much is happening in life here. I am just waiting for the day when I will get my degree from IITB and fly away.....After most of my MSc friends left the insti its really boring to stay here..May God take me out from here soon....

Sunday, February 3, 2008