Dr Archana Sharma is the only Indian on the rolls of CERN. Since 1989 she has worked on instrumentation, detector design, also development, installation and commissioning of the CMS experiment. She is now back on the drawing board designing the detectors for the LHC (Large Hadron Collider which is a gigantic scientific instrument used as a particle accelerator) upgrades. Dr Archana Sharma spoke to NDTV's Noopur Tiwari.
NDTV: Which other major discoveries can you compare this one to?
Dr Archana Sharma: This discovery can be compared to ground breaking earlier discoveries such as the discovery of gravity, or relativity or quantum mechanics sitting on giant shoulders like those of Galileo, Newton and Einstein. It's a historic moment. Trying to understand and come to grips with what we'd seen and how it fits into our understanding of the universe until today.
NDTV: What is the Higgs Boson in a layperson terms?
Dr Archana Sharma: The presence of which "affects" all other elementary particles in such a way that they acquire mass. Can be likened to a mega star - like Amitabh Bachchan Ji suddenly appearing in a stadium filled with fans, the one closest to him will get hyper excited and acquire most mass while the ones farthest from him certainly excited but will acquire less mass, so the distance from the 'star' will dictate the 'field of the star' and 'mass acquired' by the fan (particle).
NDTV: Do people know/talk enough about 'Boson' being named after SN Bose or is he forgotten?
Dr Archana Sharma: The name Boson says it all, it;s due to the Bose Einstein statistics that was formulated by the two great scientists
NDTV: Why was it important to 'see' the Higgs Boson?
Dr Archana Sharma: To culminate and complete the "Standard Model of particle physics" which lends explanation to all observed behaviour of particles, hence physical phenomena. This was the "largest" missing link, and not discovering it would mean that all our understanding of the standard model would fall apart.
NDTV: It's bit confusing to hear that we've found "a" Higgs Boson and not "the" Higgs Boson. What does that mean?
Dr Archana Sharma: It could be a family or these Bosons that we are looking for. We don't know where exactly in mass would that be so this is a first of a generation of a family that we have seen and observed now. It's very interesting to open a new door to a new era in physics. The standard model and the physics beyond predict the presence of several bosons. What has been observed is a particle which is compatible with one member of that family. The properties that allow it to be observed are its consistent mass and decay modes.
NDTV: it's is difficult to say when any discovery is made as to what exactly will people be able to do with it in the years to come. Do you have an idea what you can do with this discovery?
Dr Archana Sharma: The impact of basic research comes later naturally. What we are trying to do here is to try to go ahead with curiosities and with the research and development we want to do in the quest of the origin of the universe. In doing so we have facilitated technology development, industrial development, computing development. For example the internet was born here in CERN and that was precisely because of the need to share data to do these kind of searches. We don't know what will come in the decade to follow but we continue the quest
NDTV: We know only 6% of universe. We know nothing about 94% of dark energy or dark matter. Will these findings lead to getting know more?
Dr Archana Sharma: That's true what we understand about the universe the galaxies that are swirling around us is because of the forces that exist between them ..and when we calculate using the forces using the distances. We find that we can account only for 6% of them.. Now where is the rest of the missing mass the missing energy- the dark energy the dark matter as we call it? And in order to explain this missing mass there has to be some kind of particle, some kind of bosons perhaps- the Higgs bosons which could account for this missing mass. Now what we have evidenced today could indeed be in unlocking the door towards an understanding of this missing mass. And hence of a large part of the universe!
NDTV: What is 5 sigma? What is the highest level of certainty?
Dr Archana Sharma: Sigma is the decisive parameter of the Gaussian curve, a mathematical function that describes the distribution of data from many experiments. Citing a certain number of sigma directly translates into a probability.
1.5 sigma means just noise (background), but 3 sigma is equivalent to a 99.75 percent chance that a future experiment will yield a compatible result. So something interesting has been observed, Well, technically it's not a 99.7% chance that the result is correct, but a 99.7% chance that if they were to run the same experiment again (with the same instruments), they would get the same result.
Physicists think that only a 5-sigma result, indicating a 99.99995 percent chance that the result can be reproduced, is trustworthy and can survive the test of time. A "5 significance" describes effects where the chance of random occurrence is smaller than a few parts in tens of millions, and is agreed to be enough to claim the discovery of a new particle or phenomenon.
So basically - 1.5 sigma: noise (background). 3 sigma: Observation 5 sigma: Discovery
NDTV: What made you 'leap' into quantum physics?
Dr Archana Sharma: My teachers certainly at St. Francis Convent Jhansi, and then all my professors at the Physics Department BHU Varanasi who kindled the quest to look further into the heart of matter ... made me take the leap!
NDTV: Is there room for more Indians at CERN?
Dr Archana Sharma: Already the Indian visibility has gone much higher than yester years. The student population has multiplied ten-fold from 2001. Further collaboration possibilities are there and are being discussed with competent authorities, opening opportunities to particpate and contribute at the frontiers of science and technology. And, once India becomes an associate member, a door will open for more Indian participation
NDTV: When the discovery was announced yesterday (the 4th of July) at CERN they said more time needed to go through data. How much of a chance that this data could reveal something dramatic?
Dr Archana Sharma: Here at CERN we are saying that the next step will be to determine the precise nature of the particle and its significance for our understanding of the universe. Are its properties as expected for the long-sought Higgs boson, the final missing ingredient in the Standard Model of particle physics? Or is it something more exotic?
Story first published:
July 05, 2012 17:36 IST