Tag: physics (page 1 of 2)

The physics behind Interstellar — Christopher Nolan’s space drama

As a man of physics, Interstellar is a film I would not miss for the world; if not for the physics, for the images — and director Chris Nolan’s images have always been powerful. Interstellar does not fall short on that. However, it helps for the layperson to learn a thing or two about physics before watching the film, which is why I wrote this article — and made sure there are no spoilers.

The film is really very small, but dressed as an operatic journey through space and time. The use of physics is interesting, almost exciting, and what holds the audience’s attention is (surprisingly) as much the science as the story of a parent-child relationship.

And yet, like so many films before it, Interstellar falls short merely because it was hyped far too much and it set itself an unrealistically high barrier.

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On Physics and Hinduism

At the entrance to the Centre for European Nuclear Research (CERN) stands a 2 metre tall statue of the Hindu deity, Nataraja (see above). To the unaware, it looks like something out of place: something that does not belong in one of the world’s largest scientific research institutions. But it is only one instance of the compatibility between physics and Hinduism.

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Launching Physics Capsule, the online magazine

Long back I was part of an online science update project called The Scientific Papers. Those of you who have followed me there know it ran pretty successfully for three years before I decided to shut it down. Until now, my only presence online has been here, on my personal website; but starting June the 24th, that is about to change.

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Understanding the Higgs Boson in under 10 minutes

This is box title
This is not a scientific article and should not be treated as such. As a work of popular science, this aims to introduce the Higgs boson (AKA the God Particle as the media call it) to the common man with a limited scientific background.

As of the time of writing this article, no papers had been published by CERN describing their results/discovery of the Higgs boson and hence no statistics or other data have been provided.

It is worth noting that CERN conducted multiple experiments at the LHC and two experiments, namely ALICE and CMS both independently discovered the Higgs boson simultaneously, thus strengthening the credibility of physicists’ claims.

BY 1915, EINSTEIN’S THEORY OF RELATIVITY had — even if it made absolutely no other point to the layman — certainly put the equation E=mc^2 on almost everybody’s tongue.

It all started with the big bang, er… Einstein

The equation has far-reaching implications even to this day, one of which is the equivalence of mass and energy.

The equation, as is obvious, says that energy (represented by E) is equal to mass (represented by m.) Precisely how they are equated is another matter altogether, but what we need to gather from this equation at the moment is that Einstein said showed that mass and energy are inter-convertible i.e. he showed that at some level they are pretty much the same!

Now this cropped up a new problem. If energy and mass are so easily converted into one another, what makes mass stay as mass? And what prevents it from just zipping around as energy? To understand that we will take a quick look at mass and energy.


Mass and energy and various attractions

Following Einstein’s work came that of Hawking et al. who proved that the story of the universe starting with a big bang was truer than we thought. So imagine this: the universe has just begun and the first particles have been created and anti-particles have disappeared (we do not really know where they went yet) and mass is clumping together to form bigger masses and bigger masses are becoming stars and planets and galaxies and so on; and all of these are in a state of continuous motion.


Albert Einstein, the man who started it all — in a way

Two important questions come to mind here: One, what makes these masses move? Two, what makes smaller masses clump together to form larger masses?

The first question is easily answered. Energy that was available to these masses just after the big bang is what makes them zip around. (Now that is a scientifically meaningless sentence because there was nothing before the big bang, but let us concentrate on getting the point across first.) So now we know how this works pretty well. Like salt in water or dirt in a pond, the particles just kept moving about in space. The only difference is that this movement was perhaps not as random, but the underlying principle is quite analogous.

So far we have masses moving about, which is all well and good. Now we come to our more fundamental second question, what makes masses clump together?

Higgs’ particle

The common understanding in physics is that the presence of mass creates attraction. This is why the earth and sun attract, why two stars attract and so on. They are all massive i.e. have mass. They all contain some substance that gives them the property of mass (whatever that substance is, we do not yet know, but we will come to that soon.)

Peter Higgs at the LHC tunnel

Physicist Peter Higgs at the LHC tunnel. Courtesy AFP

So now you realise that this thing called mass is important to keeps everything stable or else all the mass would have become energy and things would have just been zipping around the universe because the energy that is already present is not going anywhere. (Remember the saying, energy can neither be created nor be destroyed? It is actually a law of Physics.) We will now see how the Higgs boson — or the God Particle as the media call it for some reason which is beyond me — will actually help us answer this question.

Nothing in physics happens without reason. To be precise, we try to find a reason for everything and the next looming question was, what gives particles this property called mass? The answer is the Higgs particle.

The PRL Symmetry Breaking Papers and the Higgs boson

In 1964, three teams of two physicists each independently — within just a couple of months of each other — published papers now called the PRL Symmetry Breaking Papers. In a sentence, these papers all addressed different approaches to the same problem of mass could arise in the circumstance we have just talked about. Of these teams one consisted of American physicist Gerald Guralnik and British physicist Peter Higgs (hence Higgs boson.)

Their solution was simple: Higgs and Guralnik attributed the presence of mass to an as yet undiscovered particle. This was not all about building castles in the air. Their mathematical working had resulted in a strong conclusion that the presence (or addition) of a particle with certain characteristics would solve the mass problem. Further investigation revealed that the particle ought to have properties that put it under a certain category of particles called bosons (i.e. particles which obeyed the Bose-Einstein statistics. In relation, another category of particles, which obey Fermi-Dirac statistics are dubbed fermions.) And this boson came to me known as the Higgs boson.


But the problem (mathematically, again,) was that the Higgs boson appeared briefly (for a fraction of a second) seconds after the big bang and then disappeared. In other words, you do not find Higgs bosons floating around to detect them like you would an electron, or a proton or a car on the road. So the only solution that lay before physicists was to experimentally re-create the Higgs boson by re-creating the big bang, the very phenomenon that kick started our entire universe.

Thus began the LHC project at CERN: a 50-year long, trial and error experiment surpassing an entire generation of experimental physicists trying to get particles to reach 99.99% the unattainable speed of light (because Einstein said so,) and getting those terribly fast moving atoms to collide — much like two rocks colliding — and break up into a million fragments — much like two rock breaking — and look for the Higgs boson among those fragments — like looking for a needle in a haystack.

And we found the needle. That is physics.

On Physicists and the law: how society has misplaced its views of science and its community

While I have often said that the community of physicists works for the common gaining of knowledge and to derive infinite mental pleasure out of that, I have also asserted that little is done towards blindly implementing it—that is what engineers are for: the Engineering – this is where the semi-skilled workers realize the work of better minds… [The] Oompah-Loompahs of science, as Sheldon Cooper puts it.

But, fun apart, my argument has always been struck, perhaps even beheaded many a time in the past. And today, I learned the height of it all—although I was quite late in finding out. Perhaps the greatest opponent to my belief is social paradigm. Non-scientists (who are the ones supposed to understand this in the first place) fail to catch on to the fact that a scientist has so much on their hands that to conform to complicated social ways becomes terribly troublesome. And, needless to mention, it is quite meaningless to hold them legally responsible for it.

Dr Adlène Hicheur

Today I read the editorial on a recent issue of Nature (Oct. 13, 2011) about the singular case of the French-Algerian physicist Dr Hicheur, which reminded me of the villain from Iron Man 2 (he is a physicist.) As it happens, the French think that Dr Hicheur, a high-energy physicist from the Swiss Federal Institute of Technology, Laussane, was plotting terrorist attacks in France.

Whether his work was so alien to the (forgive me for saying this, but) incompetent authorities who captured him on this account, that it appeared to them like a diabolical plot to blow up France; or whether they just needed a reason to feel safe and so decided to catch somebody and call him a criminal, is beyond me. Either way, Dr Hicheur has been in jail since 2009. Yes, he missed the LHC experiments altogether.

As nature rightly put it, the continued imprisonment of the French-Algerian physicist highlights the need for scientists to defend the human rights of all colleagues.

Speaking of human rights, as the Nature Editorial rightly points out, although holding a person for so long without trial is legal under France’s anti-terror laws, it is a clear violation of the physicist’s human rights.

I seem to be borrowing heavily from Nature, but here is a small paragraph that says it best, that this is nothing new: “Persecution of scientists, and physicists in particular, is nothing new. During the cold war, researchers on both sides of the iron curtain suffered for their political views. In the United States, Robert Oppenheimer’s career was ruined by rumours of communist sympathies. And Soviet scientist and dissident Andrei Sakharov spent much of the 1980s in internal exile for his outspoken views on human rights and arms control.”

Apparently, Dr Hicheur—whose online exchanges are being blocked by authorities—has been quite forgotten until recently when his defenders helplessly confessed that he can be held another 12 months before the French courts come to a decision on whether to go ahead with his trial or not.

The L’Aquila Earthquake

What prompted me to write this article was not Dr Hicheur’s case alone. Just last month six Italian physicists were jailed and are now standing trial for the manslaughter of 300 citizens for failing to predict an earthquake in the town of L’Aquila.

While that sounds like a line right out of a fairy tale, it is, sadly, true. As ABC News reported it, back in March of 2009, the panel of scientists and a local official, Bernardo di Bernardinis (who is the seventh man charged,) had a meet and the scientists declared that there was no danger then. Six days later, the earthquake struck, understandably killing many (around 309) and making as many as 7,000 people homeless.

Stating that the community was misinformed and misled, the very able community, which can take care of itself, at L’Aquila, has lodged a case of manslaughter against the six scientists. And the naive court (which in an idealistic world is supposed to have a mind of its own) has now brought them to trial, successfully hindering scientific growth.

Who was to blame when Mt Vesuvius temporarily wiped out Sicily from the face of the earth? Who is to blame every time the San Andreas fault crack open? It is nature. Nature decides, nature goes ahead with it. And as people living in such places, they ought to expect such things and be prepared with it. One does not pull the trigger at the bidding of another’s mind. It is one’s own that rules our actions.

Why did the people not look to the gods they so deeply believe in? Do they then consider physicists worthy replacements? If physicists indeed could prevent such calamities and rightly predict it every time, why would they be on Earth? They would rather fancy exploring the remainder of the universe.

Why is the weatherman not blamed everyday he reports faulty weather (which is every other day)? Because people understand. But with dead kin on their hands, man’s logical reasoning centre seems to spontaneously shift from his head to his chest.

Looking on the brighter side, unlike hardly anybody coming to Dr Hicheur’s aid (and CERN even looking the other way,) the reaction to this outrageous incident has been rather good—although more ought to be done. Soon after this shocking incident (it quite sent me staggering backwards in disbelief) about 5,000 physicists have signed a petition condemning this unprecedented court action. This is well reflected in a Nature article from July this year (2011,) on human-rights issues among scientists and in scientific collaborations.

While Dr Hicheur stays hopeful of walking free soon, the seven Italians, if convicted, face 12 year jail terms. And physicists will expectedly cry havoc and let slip the dogs of war.

In the meanwhile, if you choose to do the right thing and support the physicists mentioned in this article and probably many others who are not, then speak out on your social networking profiles and like or +1 or share this article. You can also add your views as comments below.

Spotting New Horizons

NASA's New Horizons Space ProbeOn January the 19th 2006, NASA launched a celebrated robotic spacecraft at a whopping 16.25 km/s (Earth-relative) velocity towards what was then the very last member of our solar system, Pluto.

The spacecraft, quite aptly named New Horizons, is scheduled to fly by the dwarf planet by the 14th of July, 2015 and then continue towards the Kuiper belt. Some of you might recall that New Horizons flew by Jupiter back in February 2007, by Saturn around June 2008 and Uranus on March 18th this year.

The year before New Horizons lifted off, the Hubble Space Telescope Pluto Companion Search Team found two previously unknown natural satellites which they called Nix and Hydra. Incidentally, only a few months ago, on June the 28th this year, the same team spotted a third satellite which still goes by its scientific name of S/2011 P1 (or simply P1 for simplicity’s sake!)

Tonight, one can visualise New Horizons in the night sky, perhaps using the moon as a pivot.

No, you cannot see it!

If you got your hopes high, you might want to calm down because you cannot really see the spacecraft. Think about it, having crossed Uranus, New Horizons is about 8,000 times as far from us as the moon is! And, considering that even Pluto cannot be seen from here, how can a spacecraft not quarter its size be visible? And to top it off, Pluto outshines New Horizons by about 10 billion times.

But there is fun in it if one could take a moment to visualise how this little man-made thing carrying 4,34,738 names on a CD, Scaled Composites SpaceShipOne and an American flag, among other cultural artifacts—and, of course, scientific ones—is flying, right this instant, towards the edge of our solar system.

This is not the first spacecraft to leave our Sun and its companions: the Voyager duo have done that already, but this is the first to give us a clear fly-by of five planets and many natural satellites.

As it flies past Pluto, New Horizons will have a speed of about 13 km/s. Imagine the spacecraft (pictured alongside) royally skating past the dwarf planet and taking pictures, deploying scientific payloads, all in the cold dark of outer space. And then it flies beyond the Kuiper belt, into interstellar space—where good communication will remain till 2025 (no pun intended.)

Why wait for night?

Some may be asking themselves why, if we cannot see the spacecraft, should we wait for nightfall. The reason is simple: given that we are deriving joy out of picturing New Horizons at just the right point in space, it becomes important to have a good reference system. Not all of us are astronomers with access to motorised telescopes.

A map drawn by EarthSky team member Bruce McClure explains this nicely:

Look for the gibbous moon, then a little up and left as shown. To the naked eye, your mind’s eye is your best eye! To the telescope, if you have one powerful enough to give you Pluto at least as a faint gaze, you’ll have better time visualising.

Either way, experience the joy of theoretical physics through an experiment. Allow yourself to conclusively see things one can merely visualise!

And let me know your experience below.


Astronomy lecture-workshop — Day 3

I still do not know why somebody said ‘All good things end,’ but they did and they did.

Today was the last day of the Astronomy lecture-workshop hosted by Yuvaraja’s College, Mysore and convened by the Science Academies of India. If you have not read them already, you can see what happened on the first day, here; and go through my report of the events on the second day, here.

On the last day we had just two lectures signalling the end of eleven remarkable hours that stood for everything in this workshop. The two lectures were by Prof Uday Shankar of the Raman Research Institute and Dr Sreekumar from ISRO.

Questions galore

Prof Uday Shankar opened our eyes in one way—and nobody can deny that: the fact that we stop (or have already stopped, in some rare cases,) questioning the trivial things around us. In fact he made this clear by firing questions at us regularly and insisting that we must find the answers ourselves.

So let me take a little deviation here to state his questions and that I am still finding out the answers to some of them, so I will probably write an article or two explaining the stuff once I find out. In the meantime, if you get to it first, feel free to share below!

  • Why are only few frequencies of radiations allowed past the ionosphere?
  • How many different types of molecules have been discovered in Radio Astronomy?
  • What are some famous types of molecules that are also subjects of study in other disciplines of astronomy?
  • Which type, among translational, rotational etc. of these is actually dominant in Radio Astronomy?
  • How are parsecs and lightyears related?
  • What are the frequencies of Short Wave, Medium Wave and Frequency Modulated radio signals?

On I (?,?,?,P,t)

Prof Uday Shankar began his talk with a quick recap of yesterday’s lecture and continued with a detailed explanation of how a radio telescope works and how it uses Fourier transformation of wavefronts. As he explained the parabolic structure of the Radio telescope dish and the path of incident waves on it, I (and perhaps a few others) found it almost enlightening to understand a real-life example of a mathematical model, the real-life example of the use of what were, up to this point, merely theories although they were no less interesting.

It was one of those surges of enthusiasm to deal with science that every aspiring scientist feels—and needs—now and then.

Yesterday we had discussed a formula that went I (?,?,?,P,t) and today Prof Uday Shankar spent quite some time patiently explaining how we arrive at a determination of each of them and how they matter in the equation.

Having explained the continuums of thermal and synchrotron radiations and the spectral lines of spectral line emission, he moved on to explain the resolution properties of radio telescopes.

An interesting question he mentioned that he usually asked at interviews went thus: at what distance can you, as an observer, differentiate between a two-wheeler and a four-wheeler?

The point was that the human eye can resolve up to 1” (arc sec) and the maximum distance we could do so was about 3.6 kilometers if we took the resolution of either one (two-wheelers) or two (four-wheelers) headlights. This was analogous to a radio telescope resolving a bright speck in the sky either as a system/apparent alignment of two stars or just one.

And to meet the resolving power of the human eye, a radio telescope had to be a mighty 27 km in circumference! Clearly, this was impossible and he explained—as a solution to this—Ryle and Hewish’s Aperture Synthesis process using Young’s method to obtain a number of interferences that could later be added up to obtain a final image. He also parenthetically mentioned the Gauribidanur Radioheliograph near Bangalore and the Giant Metrewave Radio Telescope near Pune.

As he finished his talk, he gave us little details of the Raman Research Institute’s Visiting Student Programme. My friend, Subramanya Hegde, who shares my enthusiasm for physics (and is definitely better established at it, anyway!) has compiled this interesting list of such similar visiting student/summer/scholarship programmes for anybody who is interested.

Challenges in outer space

Like we do not have enough challenges down here on Earth, we have bigger ones in outer space (one major hinderance being the fact that one must wear a seven-layer suit for EVA even in low-earth orbit!)

The challenges space poses for X-ray astronomers and the troubles in detecting a neutral particle like the photon and how these brilliant astrophysicists overcame it was the topic of the last lecture of the workshop by Dr Sreekumar.

He spoke of how high vacuum outgassing, unchecked space radiations and trapped charged particles in the Van Allen Belts are problematic to X-ray astronomers. After a fleeting mention of the South Atlantic Anomaly over Brazil, Dr Sreekumar explained the payload of ISRO’s upcoming mission, Astrosat.

He then explained how it becomes difficult to catch X-rays owing to their sparse distribution and unpredictable occurrences (as opposed to Radio Waves) in the universe. Then he explored the Scanning Sky Monitor [SSM] and a simple photon detector and how it works.

He then ventured to examine what properties of the photon actually matter to us (energy, arrival direction, polarisation state, and arrival time.) He also briefly showed us the Geant 4, Garfield/ANSKS/Maxwell and Charge Transport simulations; and a very basic Bolometer.

He ended his talk with a look at Point Spread Function, and a comparison between a normal pin-hole camera and the process of Coded Mask Imaging. The last bit was a quick slideshow of perhaps previously unseen pictures of the various stages of developments and the various payloads of ISRO’s Astrosat on which project Dr Sreekumar is working presently.

And it all ends

The last part of the workshop saw Dr Sreekumar telling us aspiring scientists all about how one could get into ISRO, the qualifications they look for, the kind of posts available, when best to apply, how best to approach their interviews and how he believes the scales are tipping towards pursuers of the pure sciences.

A brief valedictory function later, the lot of us had lunch, interacted with each other, exchanged a few ideas and left the workshop, three days having been spent better than we could ever have hoped for!

And that is how it all ended.

Astronomy lecture-workshop — Day 2

Today I attended the second day of the Science Academies’ lecture-workshop on astrophysics. Continuing from yesterday (you can read the update here), Professors G Srinivasan and Biman Nath gave their last lectures for this event. And two new speakers, Prof Uday Shankar, a radio astronomer at the Raman Research Institute and Dr Sreekumar, an ex-NASA scientist now working at ISRO, joined us with their lectures on Radio and X-ray Astrophysics respectively.

From Chandrashekhar to Hawking

Prof Srinivasan began from Chandrashekhar and his first attempt to understand White Dwarfs—or Quantum Stars as they were then called—and his further attempts when he arrived at what we now called the Chandrashekhar Limit. He explored the problems encountered, the concepts of Inverse Beta-Decay, neutron stars, predictions made by theories that came much later and so on, in trying to explain the various possible ends that stars may meet.

For the curious reader, apparently, a quake on a neutron star (owing to its density) will equal roughly 45 on the Richter scale on Earth. This is perhaps sufficient to shift the entire Earth from its orbital position!

Having then reached Einstein’s work, Schwarzchild’s solution of Einstein’s equations and the idea of Black Holes, Prof Srinivasan—who has worked with Roger Penrose and Hawking—spent some time sharing his experiences of those raging times when physicists all over the world—Beckenstein, Carter, Hawking, Israel, Kerr, Penrose and Zeldovich—were trying to figure out how, why and whether Black Holes would radiate.

With this ended his four lectures for this event and he left us having placed on the stage the current obstacles standing in the way between our understanding of the universe and the Theory of Everything.

Dark Matter and Dark Energy

In his final lecture of the workshop, Prof Nath explored the missing mass problem in the universe, the methods we adopt to detect Dark Matter and Dark Energy, and the formation of the first stars.

The problem he approached very systematically was how a dust grain is important to initiate the formation of a star, and—a dust grain necessarily being a heavy element—the early universe had non of it. This posed a problem as to how the very first stars formed. He explained the Hydrogen and electron addition to create a hydrogen molecule which, being the heaviest thing present then, acted as a sufficiently large ‘dust grain.’

Prof Nath explored the inhomogeneity in the cosmos and how it was increasing and causing matter to clump, providing such wonderful examples and simulations as the Millenium Simulation created by the Max Planck Institute. He ended his lecture brushing the concept of how one would detect intergalactic trace elements and how the planned Murchinson Widefield Array of telescopes in the West Australian desert is expected to ‘keep astrophysicists busy for the next decade or so.’

Radio Astronomy

Prof Uday Shankar’s first of two talks dealt with a broad introduction to Radio Astronomy, its usefulness and history and some technical aspects associated with it. In an hour sprinkled with informal communication and anecdotes of his own life as a student, Prof Shankar went on to explore how specific intensity of radio signals is dependent of spatial distribution of radio emission, its frequency, its wavelength, its polarisation studies and time period.

He related the times of Karl Jansky and Grote Reber and their discovery of radio astronomy as a science and building of the first radio telescope, respectively. He ended his introductory lecture listing the three major achievements of radio astronomy: the observations of the 21cm radiations of hydrogen; the detection of pulsars, quasars &c. and how it helped look back up to about 0.8 times the age of the universe; and, lastly, its discovery of Cosmic Microwave Background Radiations.

Bremsstrahlung, Black Holes and Binary systems in X-ray astronomy

The emission of X-rays of various types, by various phenomenon, the expulsion of X-rays owing to accretion discs in binary systems and the role of the distance of the Innermost Stable Circular Orbit [ISCO] in black holes of the prograde, non-spinning and anterograde types formed the basis of Dr Sreekumar’s first lecture.

An ex-NASA physicist with a doctorate from the University of New Hampshire and presently working for ISRO, Dr Sreekumar had tonnes of experience and knowledge to share. His lucid explanation of how one ought to read a mapped version of the universe, understand Active Galactic Nuclei and the Unification Model made the splendid one hour seem to pass with unimaginable pleasure.

Promising to speak of ISRO’s forthcoming missions tomorrow—the last day of the workshop—Dr Sreekumar spoke of Bera Rubin, SOHO’s discoveries and the mysteries of the Sun’s corona, which we are yet to answer.

Thus ended the second day of the Astrophysics workshop. I decided to keep my explanation handy and brief so as not to bore my readers who are not particularly fond of physics jargon. The details of the day was as I have said and I would be more than happy to share my experiences in more detail if anybody would fancy learning how two days with great minds is. It does sound like fun, does it not?

Astronomy lecture-workshop — Day 1

As one of my three-part series on the The Science Academies’ three-day lecture workshop on astronomy—which I am attending presently—here are the proceedings of the inaugural first day.

The Science Academies

Convenor R Srinivasan speaking at the start of the functionThe three day workshop focusing on undergraduate and graduate students of physics was convened by Dr R Srinivasan, a Fellow of The Science Academies—an association of the three leading science academies in India: the Indian Academy of Sciences, Bangalore; the Indian National Science Academy, New Delhi; and the National Academy of Sciences, Allahabad.

The Science Academies conducts regular Three-day Lecture Workshops all over the country, focusing on various disciplines; and this particular one was organised by the physics department of Yuvaraja’s College in Mysore, under the University of Mysore.

The speakers

Eminent physicists will be taking part in the event, with Professors G Srinivasan and Biman Nath of the Raman Research Institute delivering four lectures on the first day. They will be continuing onto the second day when Prof Uday Shankar, also from the Raman Research Institute, and Dr Sreekumar from the Indian Space Research Organisation [ISRO] will be joining them.

Prof Srinivasan is scheduled to deliver a four lecture series on the birth and death of stars and Prof Nath is to speak on contemporary understanding of the universe. Prof Uday Shankar will be speaking on Radio Astronomy and Dr Sreekumar on X-ray astronomy.

Prof Srinivasan is a contemporary of the likes of Fermi and Chandrashekhar which necessarily makes it a privilege to interact with him. He is an alumnus of the University of Chicago and has worked at the IBM lab in Zurich and the Cavendish laboratory in Cambridge.

The start of the day

A little more had to be scheduled, understandably, on the first day because of introductory and inaugural speeches and formalities. While that took away a whole hour of what would otherwise have been scheduled as lecture time, it did not seem much because the entire event was started on the dot, at the strike of ten, as planned.

One particular statement in Prof Srinivasan’s introductory statement that appealed to me was his retelling of Rachel Carson’s words when Carson was asked in an interview what he would like to be born as if he were to be reborn:

“[If I were born again] I wish to be born with a sense of wonder.”

—Rachel Carson

Four lectures were in for schedule today and they went on beautifully. The first was a lecture detailing the life of stars—their birth being still a debated, but unsettled issue, he did not want to begin by treading on softer paths. Titled ‘What are the stars?’ like his first book in his series, The Present Revolution in Astrophysics, the lecture began with man’s first look at the night skies. How we figured stars to be piercings in the sky and how we had but little idea about it until the 19th century. The common (and rather silly, as I thought) notion that it is the nature of things that one will never know what stars were.

A sort of history-of-physics-approach was taken, sprinkled with mathematics, all the way from Fraunhofer’s discovery of the solar spectrum in 1817 to Kirchoff’s laws of radiation to measuring the temperature, density and other physical parameters associated with the sun—indirectly—all the way to Sir Arthur Stanley Eddington’s explanation of how gravity exactly balances out the ideal gas and radiation pressures to stabilise a ball of gas: the first successful, scientific description of a star. Thus began the first part of our day.

Why even Superman cannot see inside a star

Prof G Srinivasan delivering his introductory speechThen he discussed the Virial theorem and how one could use it to calculate the temperature of the sun without any experimentation whatsoever. Having detailed how the large temperature would push all electromagnetic phenomenon inside the sun towards the X-ray region, making it invisible to man, he put forth a rather interesting hypothesis: even Superman—who has X-ray vision—would not be able to see inside a star.

By this I mean, he cannot see anything; not even the tip of his nose. Prof Srinivasan then discussed Thomson scattering and how the high temperature would ionise the particles inside the sun, giving rise to an opportunity for the fine Thomson scattering which would in turn scatter particles so much (large scattering can occur even during the time period in which the X-rays strike the nose and reach your eyes) that it would be impossible for him to see even the tip of his nose!

The talk then entered the areas of luminosity and how it depended—almost strangely—solely on the mass and not even on the radius. Then he moved on to Eddington’s proposition of fusion inside a star a full decade before the idea came out prominently; the reasons why it is impossible to manually fuse two (let alone four) protons; the Maxwell-Boltzmann distribution; and George Gamow’s brilliant discovery of quantum tunneling. He ended on a historically peaking note, detailing Hans Bethe’s famed 1938 paper detailing—as he put it—the ‘start and end’ of the entire problem of proton fusion and its complete solution/explanation.

The expanding universe

In a knowledgeable second session that seemed to last shorter than an hour, but really went well past it, Prof Biman Nath went on to introduce the attendance to the comparisons of the cosmic scales he was about to delve into. From light minute distance between the Sun and earth to light hours to Neptue to light years between stars to billions of light years across the observable universe, Prof Biman Nath dedicated a lot of time into making the cosmic size apparent.

Then he proceeded to mathematically detail a homogeneous, isotropic universe of all possible curvatures (zero, negative, positive) sans gravity and one at the centre of which an observer was and then corrected all these assumptions to arrive at a more practical situation without involving too much of Einstein’s General Relativity. The final result was the astounding proof of how Hubble’s constant—in an expanding universe which Hubble himself proposed—would not really remain constant!

To burn or not to burn? That is the question

We broke to luncheon but spent more time admiring—and buying—books (at discounted rates) from a small stall hosted by Universities Press showing well-researched, almost revered books, in the subject. Having gone past schedule by half-an-hour owing to extensions in the lecture times, the lot of us decided to spend as little time as possible in filling our stomachs and, in its stead, head back to exercise our minds with a lot more physics.

Prof Srinivasan’s second lecture on the principles of statistical mechanics—designed to prepare the audience for the third and fourth lectures—took off from where the first talk ended: the contraction hypothesis. He explained how the apparent perpetual expansion-contraction/heating-cooling phenomenon that was the strange hypothesis could be dealt with and then introduced the formation of heavier elements and its consequences.

Walter Adams’ problem of the density excess in the Sirius binary star system was next on hand and a deviation towards statistical mechanics was necessary. From here on he explored Fowler’s examination of the Eddington paradox and alongside this, explained the basics of quantum mechanics such as Heisenberg’s Uncertainty Principle and Pauli’s Exclusion Principle and the basic differences between the classical and quantum universes.

Having gone through Maxwell’s velocity distribution, zero-point motion, spin angular momentum, bosons and fermions, and once again—and this time more convincingly—re-examined Eddington’s paradox and Fowler’s alternative explanation to it, Prof Srinivasan ended his last lecture for the day.

The Darkness out there

Prof Biman Nath speaking on CMBR in his second lectureThe last lecture for the day was Prof Biman Nath’s once again, and he spoke of the history of the universe. Linking it to his previous talk with the curvatures of the universe and its expansion/contraction instances, Prof Nath went on to derive the shocking relationship between the time period, the Universal Gravitational Constant and matter density. This relation—as Prof Srinivas later explained to us—is simply shocking because it also relates the time periods of a body left to oscillate through a tunnel dug across the centre of the Earth, of the Earth itself vibrating on being struck and so on!

Then he arrived at the present situation and how we are facing a problem as the experimentally observed rate of expansion seems unlike any of the previously seen/expected circumstances. The universe had to either expand and contract or expand at deceleration up to infinity. The observed situation, however, happens to be that the universe, after having slowed down in its expansion, is now once again accelerating!

This was unforeseen and has been attributed to a mysterious Dark Matter and its associated Dark Energy. The required amount being derivable from the know value (as we have seen before) of the ratio of the present density of the universe to its critical density; the value thus attributed to Dark Matter becomes a good 0.73, which, in a ratio, equals about 73% of all the known mass of the observable universe. More about this, he promised, would be discussed the following day.

The talk was ended with an extensive look into Cosmic Microwave Background Radiations and neucleosynthesis.

Preparing for tomorrow

After the fourth lecture, a small discussion was held lasting about half-an-hour. Important, recommendable books such as Steven Weinberg’s The First Three Minutes were stated since we had just discussed close to the first two hundred seconds in complete detail.

The stage was set for tomorrow with the speakers inviting us an hour early for discussions before the actual lectures began. So my day would start at nine tomorrow and I will, perhaps, have more to share over the next two days.

Until tomorrow.

Jokes physicists crack — with strings attached

I’m an aspiring physicist. I don;t stand jokes cracked about my kind. And we don;t often crack anything we end up on the wrong end of (no pun intended.) But every now and then the layman would love a sip of all those jokes the physics community shares so I decided to put up ten of the many timeless ones—not too technical, yet not too far from the discipline. I have also added bits of explanation to serve as necessary aid. Read them if you can point to them.

[That last sentence was a rather technical quip, so it is not too much of a problem if you failed to get it. It refers to the one concept around which more jokes have been made than have been made on any other: Heisenberg’s uncertainty principle.]


“To understand something means to derive it from quantum mechanics which nobody understands.”

This is a saying that has found its way to perhaps every nook and cranny of the physics community. Nobody knows where it originated.


Apparently, the US is dotted with inns saying stuff like ‘George Washington slept here’ or proclaiming things along the same line. There is an inn in Germany that proudly says, Heisenberg may have slept here.

A quip on the Heisenberg uncertainty principle in physics, which states that it is impossible to know both the velocity and position of a particle at a given instant of time, because in measuring one, we would necessarily have disturbed the other.


A neutron walked into a bar and asked, ‘How much for a drink?’ The barista replied, ‘For you, no charge.’

It is alright if you are not laughing yet. The catch is that while most elementary particles like the electron or proton are carry either negative or positive charges, neutrons are neutral i.e. they carry no charge whatsoever.


What did one quantum physicist say when he wanted to fight another quantum physicist?

Let me atom.

A play on the phrase, ‘Let me at ‘em!’ originating most famously from Scrappy-Doo, Scooby’s nephew from the cartoon, Scooby Doo. Physicists do watch cartoons.


Famously known as Murphy’s Ten Laws for String theorists:

Murphy’s Ten Laws for String Theorists: 

  1. If you fix a mistake in a mathematical superstring calculation, another one will show up somewhere else.
  2.  If your results are based on the work of others, then one such work will turn out to be wrong.
  3. The longer your article, the more likely your computer hard disk drive will fail while you are typing the references.
  4.  The better your research result, the more likely it will be rejected by the referee of a journal; on the other hand, if your work is wrong but not obviously so, it will be accepted for publication right away.
  5.  If a result seems to good to be true, it is unless you are one of the top ten string theorists in the world. (By the way, these theorists refer to their results as “string miracles”.)
  6.  Your most startling string-theoretic theorem will turn out to be valid in only two spatial dimensions or less.
  7.  When giving a string seminar, nobody will follow anything you say after the first minute, but, if miraculously someone does, then that person will point out a flaw in your reasoning half-way through your talk and what will be worse is that your grant review officer will happen to be in the audience.
  8.  For years, nobody will ever notice the fudge factors in your calculations, but when you come up for tenure they will surface like fish being tossed fresh breadcrumbs.
  9.  If you are a graduate student working on string theory, then the field will be dead by the time you get your Ph.D.; Even worse, if you start over with a new thesis topic, the new field will also be dead by the time you get your Ph.D.
  10.  If you discover an interesting string model, then it will predict at least one low-energy, observable particle not seen in Nature. 

In summary, anything in string theory that theoretically can go wrong will go wrong, but if nothing does go theoretically wrong, then experimentally it is ruled out.

For the uncertain reader, string theory is a unification model based on the idea that all elementary particles are different vibrations of a microscopic string. Concerning #6, string theories are formulated in various numbers of spatial dimensions, of which nine is the most popular. Concerning #10, the phase “low-energy, observable particle” means that current accelerators are capable of producing and detecting it. 


 A physics professor, who was teaching a graduate course on superstring theory, decided to add an essay question to this year’s final exam. The instructions read, “Describe the universe in 400 words or less and give three examples.”

Understandably, the joke probably came up from (under)graduate students of physics; it is, nonetheless, a remarkably creative one. The catch here is that physicists have found and described—theoretically—tens of thousands of string models that describe the world equally well. There is no feasible experiment to check any of these!


It has been rumored that Edmund Scientific is trying to keep up with the times. The following amusing incident confirms this belief. The Chairman of a Physics Department ordered some lab equipment from the company. When the package arrived, a secretary opened it and found the following warning label: “Despite its superficial appearance, this product at a microscopic level might be made of strings. Manufacturer will prosecute to the maximum extent of the copyright law any attempt to make a supersymmetric version.’

String theory is the idea that the fundamental particles are extremely small vibrating strings. The most interesting types of string theories are superstrings, which are strings that exhibit supersymmetry. Supersymmetry is the idea that there is an approximate symmetry in Nature in which, for every boson (particles spinning with integer units), there is a fermion (particles spinning with half-integer units), and vice-versa. The idea is that an object can be made of normal symmetry as well as a replicated supersymmetry version.


Wanted! Schrodinger’s cat: dead and alive.

Schrodinger’s cat is a famous experiment Erwin Schroding proposed to explain the Uncertainty principle. The idea is that all possibilities (no matter how crazy) are possible mathematically (perhaps in alternate universes) and there is no absolute circumstance/situation until a measurement of it is made. In other words, the outcome of any even is solely based on the observer.

Take, for instance, a cat, put it in a box and close the box. Two valid probabilities are that the cat is either dead or alive. But to find out, you have to make an observation i.e. open the box and look at the cat. The outcome of whether the cat is dead or alive before you open the box is what is strange. Quantum physics (convincingly) shows that the cat has as equal a chance of being dead when the box is closed as is has of being alive.

In Schrodinger’s own words: ”One can even set up quite ridiculous cases. A cat is penned up in a steel chamber, along with the following device (which must be secured against direct interference by the cat): in a Geiger counter, there is a tiny bit of radioactive substance, so small that perhaps in the course of the hour, one of the atoms decays, but also, with equal probability, perhaps none; if it happens, the counter tube discharges, and through a relay releases a hammer that shatters a small flask of hydrocyanic acid. If one has left this entire system to itself for an hour, one would say that the cat still lives if meanwhile no atom has decayed. The psi-function of the entire system would express this by having in it the living and dead cat (pardon the expression) mixed or smeared out in equal parts.

‘It is typical of these cases that an indeterminacy originally restricted to the atomic domain becomes transformed into macroscopic indeterminacy, which can then be resolved by direct observation. That prevents us from so naively accepting as valid a “blurred model” for representing reality. In itself, it would not embody anything unclear or contradictory. There is a difference between a shaky or out-of-focus photograph and a snapshot of clouds and fog banks.’

In other news, the cat may have gone to the moon. Quantum physics can prove that too.


There was an old lady called Wright
who could travel much faster than light.
She departed one day 
in a relative way
and returned on the previous night. 

This was Einstein’s favourite limerick, although the origin is uncertain, and has been quoted many a time by Stephen Hawking. The physics behind it is that nobody can travel at the velocity of light, let alone supersede it. But, if we did manage it, the laws of special relativity dictate that clocks will then start traveling backwards in time. This is why the lady returns the day before she started!


Anything that does not matter has no mass.

Matter is the stuff objects contain. Mass arises because of the presence of this stuff. So anything without matter…

15 of the best quotes from The Big Bang Theory


The 15 conversations/quotes I have listed below are among my many personal favourites. If you have any of your own, do share them below!


Sheldon: I made tea. 
Leonard: I don’t want tea. 
Sheldon: I didn’t make tea for you. This is my tea. 
Leonard: Then why are you telling me? 
Sheldon: It’s a conversation starter. 
Leonard: That’s a lousy conversation starter. 
Sheldon: Oh, is it? We’re conversing. Checkmate.


Sheldon: Why are you crying? 
Penny: Because I’m stupid! 
Sheldon: That’s no reason to cry. One cries because one is sad. For example, I cry because others are stupid, and that makes me sad.


Raj: I don’t like bugs, okay? They freak me out.
Sheldon: Interesting. You’re afraid of insects and women. Ladybugs must render you catatonic.


Leonard: For God’s sake, Sheldon, do I have to hold up a sarcasm sign every time I open my mouth?  
Sheldon (intrigued): You have a sarcasm sign?


Sheldon: Under normal circumstances I’d say I told you so. But, as I have told so with such vehemence and frequency already the phrase has lost all meaning. Therefore, I will be replacing it with the phrase, I have informed you thusly.


Sheldon: Proxima Centauri’s the nearest star. The celestial bodies that follow are:
Alpha Centauri A, Toli, Barnard’s Star, Wolf 359, Laland 21185, Sirius A, Sirius B, BL Ceti, UV Ceti, Ross 154, Ross 248, Epsilon Eridani,? Lac 9352, Ross 128, EZ Aquarii A, EZ Aquarii B,? EZ Aquarii C, Procyon A.
Those are the stars that are nearest to me,
Tra la la and fiddle dee dee!


Sheldon: Is my hamburger medium-well? 
Leonard: Yes. 
Sheldon: Dill slices not sweet? 
Leonard: Yes. 
Sheldon: Individual relish packets? 
Leonard: Yes. 
Sheldon: Onion rings? 
Leonard: Yes. 
Sheldon: Extra-breading? 
Leonard: I asked. 
Sheldon: What did they say? 
Leonard: No. 
Sheldon: Did you protest? 
Leonard: Yes. 
Sheldon: Vociferously? 
Leonard: No. 
Sheldon: Well, then what took you so long?


Wolowitz (watching America’s Next Top Model): Oh, look! That’s the future Mrs. Wolowitz. No, wait! That’s the future Mrs. Wolowitz. With her head in the lap of… what a coincidence… is the future Mrs. Wolowitz. 
Leonard: Yeah, and they can all move in with you and your mother. The current Mrs. Wolowitz.


(Arguing over the name for their team after having jointly decided to take part in the University Physics Bowl:) 
Sheldon: Teams are traditionally named after fierce creatures thus intimidating one’s opponent. 
Raj: Then we could be the Bengal tigers. 
Sheldon: Poor choice. You know, gram for gram no animal exceeds the relative fighting strength of the army ant. 
Raj: Maybe so, but you can’t incinerate a Bengal tiger with a magnifying glass.


Wolowitz: Raj, did you ever tell your sister about the time Sheldon got punched by Bill Gates?
Priya: Oh, God, you’re kidding.
Raj: No, Gates gave a speech at the university. Sheldon went up to him afterwards and said, “Maybe if you weren’t so distracted by sick children in Africa you could have put a little more thought into Windows Vista.”


Stephanie: So, how was your day? 
Leonard: Y’know, I’m a physicist – I thought about stuff.
Stephanie: That’s it?
Leonard: I wrote some of it down.


Leonard: I had a great idea. Do you know how we’re always having to stop and solve differential equations, like when you’re doing Fourier equations or using the Schroedinger equation?
Sheldon: Howard doesn’t, he’s only an engineer.


Leonard: I love cheesecake. 
Sheldon: You’re lactose-intolerant. 
Leonard: I don’t eat it. I just think it’s a good idea.


Sheldon: *On cinoyter screen* Greetings, hamburger toucher. You are probably wondering why you cannot IM with your little friends about how much you heart various things. Well, this recorded message is alerting you that I am putting an end to your parasitic piggybacking upon our WiFi. If you want to remedy the situation you can contact the phone company, set up your own WiFi and pay for it, or you may apologize to me.
Penny: Well?
Leonard: I reiterate, knuckle under.
Penny: No, no, no, no, no. It is on. I am gonna introduce your friend to a world of hurt.
Leonard: Oh, Penny, you don’t want to get into it with Sheldon. The guy is one lab accident away from being a supervillain.


Sheldon: I need your help in a matter of semiotics.
Penny: What?
Sheldon: Semiotics, the study of signs and symbols as a branch of the philosophy related to linguistics.
Penny: Okay, honey, I know you think you are explaining yourself, but you’re really not.

History or Physics?

Nobody can quite say which of these two men’s great words outdo the other. As Thomas Carlyle said, “History may be called, more generally still, the Message, verbal or written, which all Mankind delivers to everyman,” or, as Lord Kelvin himself put it, “When you can measure what you are talking about and express it in numbers, you know something about it.”

Although I knew the answer, I have been pondering over the need to study history ever since fifth grade when I first remember studying it. I still have no justification to study it except for the sake of entertainment. But a few learned men beg to differ.

While I have pondered over this question for quite a while now, it was not until I came upon a similar question on another website recently that I decided to write about it.

History or Physics? The website asked. And that set me thinking once again!

Why study history?

Apparently, there are many reasons to study/pursue the study of history. The American Historical Association has come up with an extensive list, from which I will pick the five most important of the lot:

  1. History helps us understand people and society. In the first place, history offers a storehouse of information about how people and societies behave. Understanding the operations of people and societies is difficult, though a number of disciplines make the attempt.
  2. History helps us understand change. The second reason history is inescapable as a subject of serious study follows closely on the first. The past causes the present, and so the future. Any time we try to know why something happened—whether a shift in political party dominance in the American Congress, a major change in the teenage suicide rate, or a war in the Balkans or the Middle East—we have to look for factors that took shape earlier.
  3. History contributes to moral understanding. History also provides a terrain for moral contemplation. Studying the stories of individuals and situations in the past allows a student of history to test his or her own moral sense, to hone it against some of the real complexities individuals have faced in difficult settings.
  4. History provides identity. History also helps provide identity, and this is unquestionably one of the reasons all modern nations encourage its teaching in some form. Historical data include evidence about how families, groups, institutions and whole countries were formed and about how they have evolved while retaining cohesion.
  5. History lays foundations for good citizenship. This is the most common justification for the place of history in school curricula. Sometimes advocates of citizenship history hope merely to promote national identity and loyalty through a history spiced by vivid stories and lessons in individual success and morality. But the importance of history for citizenship goes beyond this narrow goal and can even challenge it at some points.

Why study physics?

As I have said already, I side with physics. The reasons, most as stated by the University of Saskatchewan, are more than just convincing; I have, however, contained my enthusiasm and picked five:

  1. Physics is the most fundamental of the sciences. It is concerned with the most basic building blocks of all things in existence. It explores the very fabric of nature and is the foundation on which other sciences stand. In a strict, true sense, every other scientific discipline is basically a form of applied physics.
  2. Physics is beautifulPhysicists love simplicity and elegance. They are constantly striving to find the most fundamental ideas that can be used to describe even the most complex of phenomena. For example Newton found that only a very small  number of concepts could be used to describe just about all of the mechanical world – from steam engines to the motion of the planets. Not only is this beautiful, it’s downright amazing!
  3. Physics encourages one to think and question. This might seem like a strange statement. The study of all subjects teach you to think. But because physics deals with the most basic concepts, the application of such techniques as “Separation of Variables” and “The Scientific Method” are never more clear than they are in the study of physics. Once mastered you will find that these methods can be applied to all subjects, including the business world and just coping with everyday life.
  4. Physics gives one a new appreciation of the world. You can look a rainbow and say “Wow, pretty colours!”, or you can marvel at the amazing interactions between photons and electrons that come together in that particular way when light from the sun strikes spherical water droplets in the sky, and that you perceive as a multicolored arc suspended in the air. Now that’s awe!
  5. Physics gives good earning. I ought to have put an exclamation mark at the end of that sentence, but I will let the latest international job trend statistics speak for itself: an engineer earns a starting salary of $30,000, and an average of $60,000; a historian earns a starting salary of $25,000 and an average of $50,000; and a physicist earns a starting salary of $60,000 and goes up to $95,000! Adding to that, a Physics Bachelor’s degree alone will leave you with an average salary of $52,000.

The Verdict

While history would be most promising in shaping a man in his responsibilities and character, physics would hardly allow one to develop questionable attributes. While history can be useful as a good afternoon pass time, it would only make sense to study physics to attempt to answer those questions far deeper within our universe which would make the questions tackled by history—no offense here, but—shallow.

But opinions differ, and I would like to hear your side of the debate. Share it below.

I’m too pretty to do math?

Recently, a magnet became available on forever21.com with the statement ‘I’m too pretty to do math’. After the company received complaints, they removed the magnet from their website.

It’s pretty disgraceful that Forever 21 would sell a magnet that perpetuates such a ridiculous stereotype. Forever 21 is a stylish clothing outfitter who sells mainly to teenage girls and young women. A magnet like this would be certain to reach a wide audience of girls. This quote is tying one’s looks to one’s intelligence – saying that subjects like math (and by extension, science) are only for girls who aren’t “pretty”. This is bad for several reasons. For one, it discourages girls from pursuing math-oriented careers for fear of being seen as “uncool”. It sends the message that girls who want to be pretty and feminine shouldn’t pursue math, which gets the reputation of being difficult and boring. It also relies on the stereotype that women aren’t as good at math as men. One article mentions that there would never be a magnet stating “I’m too handsome to do math.”

You would think that as increasing numbers of women pursue careers in science, the stereotype about women being bad at math would die down. But apparently not! While it’s good that the magnet has been taken off the website, it’s pretty terrible that it was ever available in the first place. Because math is cool! And because whether a person is good or bad at math has nothing to do with their gender.

Read the original post by Vivienne Baldassare.

The observer, when he seems to himself to be observing a stone, is really, if physics is to be believed, observing the effects of the stone upon himself.
I think physicists are the Peter Pans of the human race. They never grow up and they keep their curiosity.


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