Broad summary
(mostly aimed at non-experts)
My work is closely related to the following academic disciplines: cosmology, gravitation, elementary particle physics/high energy physics, astrophysics/astro-particle physics and theoretical physics. In what follows, I try to give a broad-brush overview of the culture in these closely-connected academic disciplines:
- My primary research interest is in a pure science (or, natural science) which means that my research is not motivated by any industrial/medical/societal applications but involves exploring the world for its own sake.
- One of the most basic endeavours in these disciplines involves pushing the frontiers of our understanding of the natural world under the most extreme conditions we could imagine. E.g. what goes on at very small length scales (at, say, distances 10000 times smaller than the size of a proton) or what could have happened in the very early universe etc.
- One of the reasons these extreme conditions are studied in great detail is that it is expected that any deviations from our current "big-picture" understanding of the natural world are likely to show up under these extreme conditions. That is, due to the success of our already existing theories about the Universe, many (but not all) of the frontiers of the "complete unknown" have been pushed quite far away from the direct human experience.
- Needless to say, to make any reliable progress, experiments are designed which could probe these extreme conditions. It should not come as a surprise that since these experiments try to probe some of the most extreme conditions, many of these experiments end up employing pretty remarkable technologies. E.g. what is now the World Wide Web was originally invented at CERN (which operates the largest particle physics laboratory in the world) so that the physicists could share the huge amount of data involved in their experiments!
- Since experimentally probing these extreme conditions is very expensive and challenging, typical experiments are huge collaborations which are often international (see, here). This is very different from our conventional picture of an individual researcher receiving grants to perform his own experiments. Typically there are only a handful of experiments or facilities of a given kind in the whole world.
- Something which comes as a surprise to many of my colleagues in other disciplines: the results of these collaborative experiments are routinely freely shared with the rest of the world so that others can make use of them to push the frontiers of human knowledge about the natural world. This is understandable: if tomorrow there is an important advancement in our understanding of the formation of first galaxies in the Universe, it won’t be a source of patents/profit for a select few but rather it would be an achievement for all of humanity!
- Most interestingly, in the academic disciplines I am talking about, the distinction between the work of a theoretician and that of an experimentalist has increasingly become more pronounced. The experimentalists work on designing the experiments (e.g. writing the software, developing the instruments, the hardware etc) while the theorists focus on how the results of the experiments can be used to draw some novel conclusions about the natural world. This is really due to increased specialization.
- Since all the theories of fundamental physics are fairly mathematical in their very nature and since for the work of a theorist, often, theoretical or mathematical consistency plays a role as crucial as the experimental results in making progress, it is necessary for every theoretician to be good at applying mathematics to various circumstances.
- I, in particular, happen to be a theoretician and I basically keep track of the results of a number of ongoing experiments to see if some interesting insights can be gained. Some of the experiments whose results could affect my current work are: particle colliders (e.g. LHC), CMB experiments (e.g. WMAP/Planck/BICEP/KECK), Gravitational-Wave Observatories (e.g. LIGO), visible/IR telescopes (e.g. HST and JWST), Fermi gamma-ray telescope, neutrino experiments, Dark Matter experiments etc.
The interface of fundamental physics and cosmology today:
The focus of my research in the recent past has been mostly in the field of
cosmology which has seen rapid advancements recently mostly due to better observations of the Universe. It may appear that one could speculate anything one likes about the big questions about the natural world such as the origin and evolution of the Universe but this turns out not to be true. Any possible speculations are surprisingly well-constrained by what we already know about nature (see, for instance
here). This is because advances in fundamental physics in the twentieth century have provided us with a very rigid theoretical framework to think about all of the natural worlds at a broad level. The most basic problems of cosmology and those of elementary particle physics have thus essentially
merged.
If we decide to pay attention to all the available constraints (both theoretical and observational) and not just a small subset of them, we are led to a picture of the Universe (see
here and
here) which appears very unexpected. Yet, admittedly, the evidence in favour of this picture is not completely convincing and so one must work harder to settle whether this picture is really correct or not. Settling this is the holy grail of the interface of fundamental physics and cosmology.
Grants/scholarships awarded:
- Awarded Indo-US Science and Technology Forum (IUSSTF) international travel grant for a few months visit to USA (Princeton University, Penn State University), 2011.
- Awarded CSIR International Travel Grant For Research Scholars for a few weeks visit to Italy (International Centre for Theoretical Physics), July 2010.