## Week 2 at TIFR

Yesterday marked the end of my second week at TIFR. I’m slowly getting acclamatized to life here and the rather hard routine of going to bed at 10:30 PM and waking up at 6 AM. I now understand why Dr. Suresh told me that being bused in is, in some ways, a good thing. Maybe my body will learn to go into deep sleep real fast, at last.

That apart, the food here is slowly getting boring, my project is slowly progressing with a lot of back-tracking (like those progress bars on most applications – the KStars conjunction tool for instance – that seem to make time travel in the past a reality), and I’m learning stuff.

This week started off with some more reading of Frisch’s book on ‘Turbulence’. I finally managed to start Chapter 6, on Kolmogorov theory. Early this week, I had a long discussion with Prof. Spenta Wadia, which eventually gave me an understanding of Functional Integrals, the Feynman Path Integral formulation… He loaned me his copy of Feynman and Hibbs (Quantum Mechanics and Path Integrals) from which I learnt the basics of the path integral formulation of QM. I think it’s a nice idea. He said he’d also teach me the Dirac equation sometime for fun.

We were trying to write part of the Navier-Stokes equation as a potential energy. I even came up with a solution, that I realised was incorrect because of an extremely stupid mistake I had made – I had written the convective derivative which is $v^i \partial_i v^j$ as $\partial_i v^i v^j$ which is zero for an incompressible fluid! For a whole day, I thought I was right and we tried to put in Lagrangian multipliers into the potential to fix the $\partial_i v^i$ appearing in it. When I realised my mistake yesterday, I was looking for other possibilities and realised that no “local” potential is possible. In the evening, my guide told me that it was not possible because the field was not curl-free in the first place to get a potential term! We’re now left to deal with more complicated stuff, and in the meanwhile I’m going to continue my reading of Frisch’s book and Srinivasan’s articles on turbulent flow. But the point of this exercise for me, was that I learnt something – and I got a feel for what research might look like.

Recently, there were two interesting colloquia here. I attended a talk on the LHC and the Dark Universe by Dr. Rolf Heuer, Director General of CERN. He had pitched it at a low level, so I could understand a fairly large part of it. There was yet another colloquium by Dr. Atsuto Suzuki, Director of KEK which I attended, in which Dr. Suzuki talked about Neutrino Telescopes, the Solar Neutrino problem, and the Super-Kamiokande and KamLAND neutrino detectors. Again, the talk was at a popular level, so I could understand most of it. The departmental introduction talks for VSRP students ended this week, with the last one being the Theoretical Physics department. I learnt quite some stuff there as well.

I also went to Dr. Umesh’s labs, where he did his research to earn his PhD, and built quality instrumentation. He also showed plots of electron scattering by Hydrogen molecules that showed the Young’s double-slit interference due to the two hydrogen atoms, which he had talked about in our class. I also saw parts of the Pelletron from outside. I hope to visit the Petawatt LASER lab and the Pelletron some time.

I’m now trying to find ways to spend the weekend.

I completely subscribe to what your guide said about reconstructing things. You get to have lot of fun when you rediscover things. And yes, it is not always true that you will have time to reconstruct things you need yo understand, so make the best use of this time ðŸ™‚