Philosophy-centric Physics graduate education

As a part of my Physics education, I have had the pleasure to attend a large number of courses. Typical trajectory of a physics course can be summarized as follows: we start off by picking up necessary math skills (for example, vector algebra and calculus for Newton’s laws of motion), then we use these skills to unpack the concise statements of physical laws (for example, what does F=ma mean?) and at the end, we apply these laws to specific problems to improve our understanding of the laws (for example, if an object of 5 kg is subjected to 4 N of force, what’s the acceleration?).

I attended a Machine Learning course recently which was different from traditional courses in more than one ways. It was based on flipped classroom concept; we did simulations in class, we had discussions in class and we read research papers as part of assignments. One can argue that the unusual strategy suited the course because it was on Machine Learning, which is still in infancy unlike Electrodynamics. However, I believe that the same strategy can be applied to graduate courses teaching well-established fields. Although flipped-classroom approach has been applied to undergraduate courses in many universities, it’s hard to find a Physics graduate courses, which has been taught in non-traditional approach.

The two most important skills, which I learnt in that course, was to ask big questions and read research papers critically. I am going to explain below what exactly I mean by the above terms and why I think these skills are crucial for learning how to do research. These two skills have never been taught to me in any other course even though the goal of any graduate course should be to prepare graduate students for their life as a researcher.

Why learning to ask big questions is important for a budding researcher? Asking the big questions helps one to understand what’s the whole point of a certain subject (for example, what is Machine Learning and why it’s hard?). This is the first step that one can take to get a sense of where the community currently stands. Once we know what is the current body of knowledge, we need to ask second set of questions : how can we push the scientific community forward?

To give illustrations, let me give examples of big questions that can be asked and explored in graduate courses:

  • In a Quantum Mechanics course, we can start by asking what’s a quantum system – does quantum systems need to be necessarily small and discrete? When does a system stop behaving like a quantum system and starts becoming like a classical system? How do you design experiments that measure the quantum behavior of the world? Stern-Gerlach experiment and Feynman’s double slit thought experiment are good examples to illustrate the subtlety of quantum experiments.
  • In a Statistical Physics course, we can ask what’s the recipe of studying complex physical systems according to Statistical Physics? What is ergodicity and when does it fail? Why Anderson argues More is Different? In other words, why reductionist principle can fail to explain an emergent phenomenon like Bose-Einstein condensation? How Quantum Statistical Physics is different from Classical Statistical Physics?
  • In a Quantum Many-Body Physics course, we can start by asking why many-body systems are hard to simulate on classical computers? If one starts from non-interacting limit, can we use perturbation to understand the effect of interaction in a many-body system? Would we ever discover a general principle that goes beyond mean-field theory? What’s the effect of infinite dimensional phase-space on physics of many-body systems? Anderson Orthogonality Catastrophe is a perfect example illustrating this point.
  • In a Quantum Computing course, we can ask what is a quantum computer? Is a quantum computer necessarily better than a classical computer? Why Feynman argued that a quantum computer can help us simulate a quantum world?
  • In a Machine Learning course, we can ask what is machine learning? What is the recipe of studying complex systems according to machine learning? Why machine learning is hard?
  • In a Biophysics course, we can ask what defines life? What measurements can be done to distinguish between a living and non-living beings? What is Physics of Life – would we ever discover some new fundamental force in living beings?

The whole point of these questions is that we are spending time in class thinking about what are the most important questions for the field, how does the subject traditionally answer them and is there a better way to go about solving them?

When we start asking these questions, it’s natural to ask how scientists before us tried to answer them. This brings me to the second skill: reading research papers critically. Before I go into details, let me list some resources which I found useful in improving my paper reading skills. I recently got to know there is a systematic method called QALMRI to learn how to read papers, which people follow in cognitive science. Also, I have found Terry Hwa’s reading guide useful.

It’s important to note that merely assigning classic papers to read without any proper class discussion would not help. A class discussion would help students to see what they missed in their first reading. Further, reading classic papers can also help students write better papers in future.

I have seen that almost all Professors know classic papers in their field, but curiously they rarely assign these papers as part of course assignments. I don’t know why they don’t. However, they definitely assign a lot of problems.  They seem to be convinced that physicists learn best when solving problems and calculating physical quantities.

Sometimes, calculating something doesn’t necessarily leads to better understanding. You can solve problems by following some algorithm without any deep understanding; you need to stop and ponder why something is working (or not working). Don’t get me wrong, it’s definitely helpful to solve textbook-style problems to gain some intuition. But I feel since we physicists are so good at calculating things (using spherical cow approximations), we forget that starting point of any research is asking the right kind of questions. Also, we sometimes ignore the fact that there are other ways of acquiring knowledge – asking big questions, whose answers can’t be necessarily calculated at the current moment and learning from someone else’s calculation/simulation/experiment by reading their papers. Along with problem solving skills, I am arguing here that above mentioned skills should be also taught in classrooms.

Graduate courses that emphasize asking big questions and reading papers critically are needed to train next generation of physicists, who don’t only know how to solve problems but also to recognize which problems are important. This philosophy-centric teaching approach is truer in spirit to the goals of philosophiae doctor (PhD) degree.


Classification of fiction books

Before I begin giving you my classification, let me first answer the question ‘Why a new classification?’  Of course, we already have literary genres, which is simple enough to be used by everyone in classifying fiction books. The problem is that it doesn’t have any systematic criteria on classifying fiction books. Sometimes, it is named based upon how you feel while reading it: if you get scared while reading, it’s called horror; if you are thrilled to read it, then it will be called a thriller. Sometimes, it’s based upon the nature of story: if it is based on a scientific concept, then it’s called sci-fi, if it’s based on a crime, then it’s called a crime novel.  

Alright, once I have established the need for another classification scheme, let me tell you what I hope to achieve by a more systematic one. Using this scheme, I hope readers, both old and new, can have a more enjoyable reading experience by knowing better how to approach the book at hand. And hopefully, it can be used as a guide to pick up a right book.
What’s the classification scheme I have used? We will compare the pace of the characters versus that of the plot in a book.  Based on this, there are three kinds of fiction books in this world:
1. Fast paced: The one in which the  plot moves faster than the character. These books usually focus on the plot. As a reader, you will find yourself engrossed in the twists and turns of the plot. While reading the book (and if it is really good), the only thing you want in your life is to reach the end of it. Most of the suspense thriller/suspense and crime novels fall into this category. For example, Sherlock Holmes series and works of Agatha Christie.
2. Slow paced: The other extreme is the one in which characters move faster than the plot. These books spend a lot of time on sketching characters, and their environment. While reading such stories, you might wonder why should you care about the weather or the clouds or the trees around? The book believes that by knowing about the environment, you will get to understand more about the characters and their moods. You would find that in these books, most of the time the plot is not moving at all, while one character is moving from one place to another. The place might not be a geographical place; it might be moving from one place to another in an abstract space as far as characteristics of the character (like mood or age)  is concerned. While reading such a book, you will notice the mood swings of both the characters and yourself as a reader. And you should never be in a hurry to reach the end of it. For example, Lord of the Rings,  A song of Ice and Fire,  A Suitable Boy,  Atlas Shrugged, and Fountainhead.
3. Medium paced: The third one lies in the vast middle of this spectrum.  The author takes time to carve out both the characters and the plot. The author will try his/her best to strike a balance between giving details about the plot and the characters. For example, Harry Potter series, To kill a mockingbird, Kingkiller chronicles (less popular but highly recommended), Kite Runner.
For someone who is just starting their journey into fiction books, I would suggest depending upon your mood and interest, pick either the first or the third category. I feel from my experience of reading Lord of the Rings that you should leave the second category for the later part of your journey.
P.S:  Thanks goes to my friend Vaibhav Karve for seeding this idea into my head.


The raindrop falling on his vulnerable bald head found his senses to be numb. He could not listen to rain thumping his Maruti car’s roof or his two-storied house’s pipe regurgitating the muddy water from the roof into the drain.

“Beep! Beep!”

The blaring horn from the car brought him crashing back to his senses. He realized that his throat was parched and he was obstructing the road in front of the house. He turned back and went inside. He slumped into his sofa, and found himself really tired as if he was coming back from a twenty-year long rock-climbing expedition. Pappu, their light brown labrador greeted him with unusual silence. Pappu chose to curl up in a ball next to his right foot, and closed its’ big sad eyes. Both were her equally possessive lovers, and they never got along well for long, but today they were brought together by the overwhelming emptiness.

He found the whole house to be perfectly normal. There were no glasses broken, no chairs upturned, no books thrown. Everything was as neatly kept in its own place as if she were still here spending her afternoons organizing stuff as she used to do while he took his nap.

He felt weird in his mouth as if one of his teeth had left its place, but he could not remember when it happened. Suddenly, he found his tooth in his left hand, and when he looked at it, it crumpled in front of his eyes. In horror, he put his finger on his mouth, and then he felt all of his teeth falling out one by one.

Shrugging the napping dog off his foot, he ran towards kitchen breathing heavily to get some water. Pappu didn’t like being woken up just like she hated being woken up, and he started barking at him as he chased him. When they reached kitchen,  he could not believe his eyes. The dog kept barking louder, and louder. The bloody red water was flowing onto the floor from the open tap in the overfilled wash basin. Her body was there on the floor immersed into water…and then everything came crashing back to his memory. He could not take it anymore. He found himself to be falling into nothingness. His knees gave away, and his body crashed onto the flooded floor…


“Darling, are you okay?”

He woke up with a start in the dead of night in his warm bed. His wife had switched on the bedside lamp, and was looking at him in concern. She put her hands into his hair, and found his head to be wet with sweat. She grabbed a tissue paper from one of her smart pockets in their bed, and wiped off his face and dried his head. She didn’t understand why he was looking at her in shock and relief as if she just came back from death.

“Thank God, you are still alive!”

“Do you want to talk about it?”


She brought him closer and put his head on her chest. He put her arm around her, and dozed off in a few seconds. She kept looking at him, while he breathed heavily, for some time before she put off the lamp.

Mleccha: a historical word

In my family, we all agree that my mother has got the most colorful way of showing her displeasure. While she would unload her angst on us with words in her mother-tongue dialect Bhojpuri, my sister and I would  listen to her words with amazed look on our faces. Armed with whatever knowledge of Hindi and English languages we had, we would be lost in dissecting those foreign words enthusiastically. Of course, seeing the topic of discussion had got changed, my mother would not be happy at all to find her energetic outburst have been of no use!

One of the many imaginative words that I learnt from my mother was “mleccha”. I never understood the meaning of this derogatory term. At best, I could imagine this to be closer to Hindi word “mcchuwara” (fisher). Surrounded by disappointingly uninspiring Hindi books, I never found anybody else using this word until a few days ago, when I found this word at a totally surprising place- a history book. Little did I know this was historically used by people living in what is now the frontier between India and Pakistan to describe others who they didn’t like.

As I was understanding the dynamics between Harappans and Aryans while I was reading John Keay’s India: A History, there was this word sitting quietly waiting for my attention. I was so surprised to know that mleccha is a Sanksrit word. How could a language which people claim to be so elegant have this “uncouth” word! And I was not wrong. It turns out philologists have spent years of research on this word and they insist that its origin can’t be Sanskrit. It might be true that Aryans used this word to describe indigenes, who appeared to them as “dark,  flat-nosed, uncouth and incomprehensible.”

In fact, on googling, I found a Wikipedia article on Mlecccha, and there is a dynasty by the same name.
Next time I am going back to India, I am going to note down every new word my mother throws at me. Who knows I can learn another historical word!



A foreigner in Boston

It’s been over a month here in Boston since I began the new chapter of my life. Right from the moment, when I was peeping down to have a look of blue Massachusetts Bay from my plane’s window to now, I have felt puzzled, amazed, stupefied, and complete silence. It’s like the scene from Harry Potter book-

“Seventeen silver Sickles to a Galleon and twenty- nine Knuts to a Sickle”, Hagrid said to awestruck Harry. “See, Harry, I told you. It’s easy enough!”

This past month I have been playing around, and learning to find how things work here and I find it’s not that easy. At least for me. I have tried to learn to answer “How you doing?” spontaneously when asked, “How you doing?”. However, since I don’t expect random people to greet me when I am walking on street, I am too slow more often than not and then I just manage to put a fake smile to acknowledge their greeting.

While I am trying to rhyme my can’t with ant, and learning to say bell-pepper (capsicum), eggplant (brinjal) and trashcan (dustbin),  I have to stop myself really hard from running to every Indian I spot on the street. Whenever they see my eager eyes, they consider me for a moment before pulling over their unfriendly mask of I-don’t-know-you. I start hiding my craving for everything that is Indian, and let my instinct become visible only when I am relishing pakoda  while I am reading Jhumpa Lahri’s Sexy (set in Boston) in the private confines of my kitchen. I count the number of American jokes which I have understood and the ones which I have laughed at the right time, and I convince myself that I am doing a decent job. It seems that I have began blending in with the heterogeneous crowd, being less conspicuous in the sea of diversity and finally adapting to my new life in Boston.

However, this all pretense gets tossed to the wind, whenever I wake up in the morning, and I find myself lying down on a mattress in an half-empty room. Everything around me is familiarly strange.  I find my eyes on the same level as the white pair of shoes kept on the floor. “No, I can’t be sleeping on the floor!” For a moment, I forget how I end up being in that room. The reality evades my consciousness. “It’s my new home, idiot!” I frantically look for my smart phone so as to call up someone. I can’t find it. It’s not surprising, I must have kicked it during my sleep. Then in an attempt to calm myself down, I convince myself that it’s just a strange dream, and then my mind says, “Only with one difference. Unlike others, this won’t end”, and with that, I fell into the endless trap that mind plays with you often. The girl whom I kissed yesterday night comes flooding back, and I get lost into her fragrance. I have got the stupid smile on my face as I keep staring into something beautiful from my nostalgic past. It takes me longer than a moment to break the trance. The azure sky with white patches of cloud visible from my window reminds vaguely of a day which I have spent playing cricket with my friends in my childhood. The view comforts me a little and everything starts seeming normal.

And just then the American red squirrel stares at me amusingly from the tree outside my window, and sniffs something foreign in air.

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