Tagore and Einstein Discuss Physics and Philosophy

Rabindranath Tagore was an Indian polymath who became the first non-European to win the Nobel Prize in Literature for his profoundly sensitive, fresh and beautiful work, Gitanjali, in 1913.

He is also well known to have written the national anthems of Bangladesh and India as well as gave music to the national anthem of Sri Lanka. As a result, his influence, especially in the sub-continent, is going to live forever.

Similarly, Albert Einstein too received the most coveted prize in the year 1921 mainly for his explanation of the photoelectric effect. But he has become more famous for his theories of relativity and for the equation E=mc² meaning the equivalence of mass and energy. Einstein was not just a great scientist but also a man deeply involved in the matters of society and politics.

The two gentlemen decided to meet on July 14 (1930) in Berlin at Einstein’s place to talk about variety of things, ranging from the nature of reality to their individual tastes in music. Tagore in fact suggested that their conversation be recorded and put together in a book.

However, when they met, Tagore did not know sufficient German and Einstein’s English was too weak to converse with. Hence they had to bring interpreters for the meeting. Neither Tagore nor Einstein was happy with the recorded conversation as the translations had lost their charm. Therefore, they themselves corrected their own parts before making it public. The book was published titled, Science and the Indian tradition.

On truth and beauty

Einstein: Are truth and beauty independent of man?

Tagore: No.

Einstein: If there would be no human beings any more, would the Apollo of Belvedere no longer be beautiful?

Tagore: No.

Einstein: I agree with regard to this conception of beauty but not with regard to truth.

Tagore: Why not? Truth is realized only through man.

Einstein: I cannot prove if my conception is right but that is how I see it.

Tagore: We individuals approach truth through our own mistakes and blunders, through our accumulated experiences, through our illumined consciousness – how, otherwise, can we know the truth?

Einstein: I know not how to prove scientifically that truth must be conceived as truth and be independent of humanity; but I believe it firmly. I believe, for instance, that the Pythagorean theorem in geometry is independent of the existence of man. If there is a reality independent of man, I believe, there is also a truth relative to this reality.

Tagore: But truth must essentially be human otherwise whatever we individuals realize as true can never be called truth, at least the truth which is described as scientific and which only can be reached through the process of logic, in other words, by an organ of thoughts, which is human. The nature of truth which we are discussing is an appearance, that is to say, an illusion.

Einstein: The question is whether truth is independent of our consciousness. According to your conception, which may be the Indian conception, truth is not the illusion of the individual, but of humanity as a whole.

Tagore: What we call truth lies in the rational harmony between the subjective and objective aspects of reality, both of which belong to the personality of man. In any case, if there be any truth absolutely unrelated to humanity, then for us it is absolutely non-existing.

Einstein: Then I'm more religious than you are!

Tagore: I believe more in the universal human spirit, in my own individual being. I never believed in any religious institution and practices whether it was Hinduism or Islam or Christianity. My religion is realized through the divinity of humanity and the humanity of god.

On duality

Tagore: I have been told that in the realm of infinitesimal atoms, chance has its play; the drama of existence is not absolutely predestined in character.

Einstein: The facts that make science tend toward this view do not say goodbye to causality. In the macro-world, there is order as well as predictability. However, in the minute world, like you said, the order is not perceptible.

Tagore: I find a parallel in human psychology. Our passions and desires are unruly but our character subdues these elements into a harmonious whole. Does something similar to this happen in the physical world? Are the particles rebellious and dynamic with individual impulses? And is there a principle in the bigger world which dominates them and puts them into an orderly organization?

Einstein: Even the particles are not without statistical order; atoms of radium will always maintain their specific order, now and ever onward, just as they have done all along. There is, therefore, a statistical order in the particles.

Tagore: That is beautiful. It is the constant harmony of chance and determination which makes nature eternally new and living.

Einstein: I believe that whatever we do or live for has its causality; it is good, however, that we cannot see through to it.

On music

Einstein: How’s the Indian music different from that in the west?

Tagore: The musical system in India is not so rigidly fixed as is the western music. We praise the composer for his genius in creating a foundation, but we expect from the player his own skill in the creation of variations of melodic flourish and ornamentation.

Einstein: That is only possible where there is a strong artistic tradition in music to guide the people’s mind. In Europe, music has come too far away from popular art and feeling and has become something like a secret art with conventions and traditions of its own.

Tagore: So you have to be absolutely obedient to this too complicated music.

Einstein: Can the Indian music be sung without words? Can one understand a song without words?

Tagore: Yes, we have songs with unmeaning words, sounds which just help to act as carriers of the notes. In India, the measure of a singer’s freedom is in his own creative personality. The singer is at liberty to add his own words to the song which he is singing.

Einstein: It requires a very high standard of art fully to realize the great idea in the original music, so that one can make variations upon it. In our country the variations are often prescribed. It seems that your music is much richer in structure than ours. Japanese music also seems to be so.

Tagore: I am deeply moved by the western music and I feel that it is great, that it is vast in its structure, and grand in its composition. Our own music touches me more deeply by its fundamental lyrical appeal. European music is epic in character; it has a broad background and is Gothic in its structure.

Einstein: Yes, yes, that is very true. When did you first hear European music?

Tagore: At seventeen, when I first came to Europe. I came to know it intimately, but even before that time I had heard European music in our own household. I had heard the music of Chopin and others at an early age.

What Are 7 Qualities of A Great Physics Teacher?

Educational rockstar

All the excellent physics teachers are great communicators who draw the attention of their students without fail. Why, because they are witty, humorous and confident when they teach physics. Take Professor Walter Lewin, for example, whose videos have received more than 50 million views on YouTube, collectively.

Real world examples

There are innumerable teachers who merely repeat what's in the textbook and then there are few, who make physics fun and accessible through analogies plucked from daily life.

Paul G. Hewitt has a unique approach to teaching physics that focuses on the ideas rather than the often daunting mathematics. He has believed that with a strong conceptual foundation, students are better equipped to understand the equations and formulas later.

Passion for it

A good physics teacher has not only deep knowledge about the subject but also desire to pass it on to others. Richard Feynman had once said, "I find that teaching and the students keep life going, and I would never accept any position in which somebody has invented a happy situation for me where I don't have to teach. Never!"

To this day, Feynman is mostly remembered not because he was a great scientist but because he was an extraordinary teacher who became guide for his students in time of trouble. He used to say, "teach them to doubt, to think, to question, to make mistakes, to learn from their mistakes and most importantly, to have fun in their learning."

Adaptable

All the good physics teachers listen well, focus on collaboration with their students and adapt to new teaching methods. Sal(man) Khan from Khan Academy is an example who's determined to teach by using technology. Also, Professors Walter Lewin and Gilbert Strang from MIT have adjusted well even in old age.

Gilbert Strang

Approachability

Every good physics teacher is friendly and approachable. Furthermore, he/she is not afraid of doubts, problems and/or feedback from their students. In fact, the good teacher is forever ready to struggle with questions, also taking their students as partners! Walter Lewin, for example, used to accept questions on Quora. Now, he is more available on YouTube and replies to questions in comments. He is 85 years old.

Candle in the dark

In early 1980, H.C. Verma joined the Patna Science College as a lecturer. He found that the students were uninterested in physics because it was too difficult. Also, there weren't any textbooks available in the Indian market which were even remotely relatable.

Thus, a young Professor Verma set about to solve the problem of his students. Ten years later, in 1992, a new book by the name, 'concepts of physics' was published and it became an instant favorite in India. To this day, the book is being used by many science and engineering aspirants. Professor Verma became and burned like candle, illuminating the darkened lives of incurious physics students.

Self development

A bad physics teacher will often beat around the bush in order to hide the fact that he/she does not know. On the other hand, all the good physics teachers accept that they don't know and/or that they're wrong, and moreover, they want to continue to learn. 

10 Examples of Physics From Everyday Life

Not every student will grow up and study physics on a deeper level, but physics extends well into our daily life, describing the motion, forces and energy of ordinary experience. Therefore, it should be possible to illustrate to anyone the physics of everyday life, with examples of course.

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Image formation

Have you noticed that when standing inside a room at night, you can often see your reflection in a pane of glass? In similar way, because there is much less light coming from the bottom of a lake, the surface of the lake will act like a mirror.

But an image can also be formed by refraction. A fish seen in the water will usually appear to be at a different depth than it actually is, due to the refraction of light rays as they travel from the water into the air.

Lastly, there exist phenomena which appear due to combination of reflection and refraction. For example, a rainbow is seen when light passes through water droplets hanging in the atmosphere. The light bends, or refracts, as it enters the droplet, and then reflects off the inside of the raindrop.

Washing machine

The dryer of washing machine is a rapidly rotating container that applies centrifugal force to its contents. The centrifugal force acts in a direction away from the centre and hence can be used to throw the water molecules on the clothes radially outwards during the spin cycle of the washing machine.


Static electricity

When two objects that are not good electrical conductors are rubbed together, electrons from one of the objects rub off onto the other.

The more rubbing between two objects, the more static electricity build up and the larger the electrical charge.


Road safety

When brakes are applied to a moving car, the car and lower portions of the passengers attached to the car come to immediate stop, but their upper portions fall forwards, because of inertia. This is why seat belts as well as air bags are installed in the car.

Roller coaster

The first hill of the ride is always the highest one so that the car collects enough energy to go through all the elevations. As the car goes down, its potential energy decreases but kinetic energy increases. If added together at any part of the ride, the kinetic and potential energies of the car will equal the potential energy that the car had on the first hill.


Spinning

When the figure skater draws her arms and a leg inward, she reduces her moment of inertia thus rotating at a faster angular speed. This is due to conservation of angular momentum.

Handle of the door

If you apply force close to the hinge of the door, the door will not open as it will not be able to rotate about the hinge. But, when you apply the same force farther away from the hinge, the torque will be larger. Hence, the door opens easily with less effort.

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Falling down

Suppose you are climbing a tree, and suddenly you slip and fall down from the tree. Then, you may break a bone or two. But if same thing happens to a little ant, that is, if it falls down from height, it does not get hurt. Why is it so?

From ant’s point of view, the atmosphere is thick and viscous and its experience of falling from a height is similar to ours when we fall through water to the bottom of the pool. The air underneath the falling ant becomes like a large cushion of safety.


Roundness

Nobel prize winning physicist Richard Feynman explains why little drops of water are round in the following video.



Sound game

When a water bottle fills up, the air column or amount of air inside the bottle decreases. As a result, the pitch (or shrillness) of the sound will increase, as it is inversely proportional to the length of vibrating air column. Therefore, you can tell exactly when the bottle is full without even looking.

Summing up

It is hard to imagine of life without physics. Even though one may not be equipped with the kind of mathematics required to fully understand these physical phenomena, one can surely appreciate the fact that they are there. Lots of other examples are available and you just need the eye to recognize them.

Dirac, a fusion of genius and madness, according to Einstein

Paul Dirac, one of the most famous scientists of the 20th century, was a very quiet man. So much so, that his colleagues at Cambridge jokingly defined a unit of speech called "dirac", which meant one word per hour!

But whenever he did speak, Dirac used to extend his abstract thinking to interpret the world literally. This inevitably led him to being an anecdote generator throughout his life and many stories about him abound.

Why do you dance?

In 1929, Dirac and Heisenberg were on board a ship to Japan for attending annual science conference. Werner Heisenberg who happened to be quite a ladies man, used to dance with the young girls on the ship before dinners, while Dirac used to sit watching.

One such evening, Dirac asked, "Heisenberg, why do you dance?"

"When there are nice girls, dancing with them is a pleasure," Heisenberg replied.

Dirac pondered this notion for a while, then blurted out: "But, how do you know beforehand that the girls are nice?"

Heisenberg burst out with laughter.

Physics versus poetry

Dirac and Oppenheimer spent some time together in Göttingen. The two young physicists from different parts of the world had become good friends. In one of these days, Dirac noticed that Oppenheimer wrote poetry.

Dirac asserted, "Robert, I do not understand how a man can work on the frontiers of physics and write poetry at the same time."

"Why not?" Oppenheimer asked.

"In physics, you want to tell something that nobody knew before, in words which everyone can understand. In poetry, however, you go on to describe something that everybody knows about, in incomprehensible ways."

Oppenheimer was left too confused to respond to that.

Dirac went on to say, "The two are incompatible!"

His comments would strike people as odd at first but they would quickly realize that Dirac made perfect logical sense.

Finish this sentence

Once, Dirac and Bohr were seated in the same room. Niels Bohr, known for being a perfectionist, was writing a scientific paper while mumbling at the same time as was his habit.

After some time, Bohr became really frustrated and stopped. He complained, “I do not know how to finish this damn sentence!”

Dirac retorted, "I was taught at school, never to start a sentence without knowing the end of it."

Dirac said something so profound, with such a straight face, that Bohr went on to comment, "Dirac was the strangest man who ever visited my institute!"

I have an equation

American physicist, Richard Feynman, born in 1918, grew up idolizing Dirac. About 40 years later, they met in Poland at a conference. Richard Feynman, by then a theoretical physicist himself, was building upon Dirac's great work.

Feynman, the chatty one, spoke at length, as he wanted to describe new ideas to his hero. Dirac, perhaps intimidated by Feynman's over-enthusiasm, remained quiet all along.

Feynman started to see that it was extremely difficult to get anything out of Dirac. But then, after a long silence, Dirac says, "I have an equation. Do you have one too?"

Dirac also went on to explain as to why he spoke so little, “There are always more people willing to speak than there are to listen.”


That wasn't a question

In 1932, Dirac was appointed the Lucasian Professor of Mathematics at the University of Cambridge. During one lecture in class, a student raised his hand and said, "I don't understand the equation on the top-right-hand corner of the blackboard."

Dirac simply nodded his head in agreement and continued unabated. When asked again, he expressed puzzlement because he thought the student had simply uttered a fact and not asked a question.


Summing up

Paul Dirac knew not when to say what. He remained merry in his own company but suffered agonies if forced into any kind of socializing or small talk.

His colleagues  in Cambridge described him as a “lean, meek, shy young fellow who goes slyly along the streets, walks quite close to the walls, like a thief, and is not at all healthy.”


Albert Einstein once commented on Dirac: "I have a lot of trouble with Dirac. This balancing on the dizzying path between genius and madness is awful!"

Dirac quantised the gravitational field, formulated the most logically perfect presentation of quantum mechanics and predicted the existence of anti-matter. At the same time, he was also equally famous for his strange, unapologetic behavior.

Nikola Tesla, a college dropout who changed the world

On 10th of July in 1856, Nikola Tesla was born at midnight during a lightning storm. The midwife thought the violent storm was bad omen, "This will be a child of darkness", she declared mindlessly."No, replied Tesla's mother, "he will be a child of light".

His father, Milutin Tesla, was orthodox christian priest while his mother, Đuka, was hard working housewife. They recognized very early that their son was unlike other children. Young Tesla was creative, curious and blessed with photographic memory.

Milutin, a devout man, wanted his son to become priest like himself but Đuka encouraged Nikola to study science instead. Even though she had never received formal education, Đuka had the talent for making mechanical appliances at home.

Nikola Tesla's parents

By the age of 16, Nikola was able to perform integral calculus in his head which prompted his teachers to believe that he was cheating. Tesla credited his eidetic memory and creative abilities to his mother's genetics and influence.

He finished four-year high school term in three years graduating in 1873. During those times, high school graduates were forced to join the military but Tesla ran away and remained hidden for over a year wearing hunter's garb to escape conscription.

Tesla returned in 1875. Then, he enrolled for engineering degree at Graz University of Technology in Austria.

In first year, he never missed a lecture, earned the highest grades and even received letter of commendation from the dean to his father, which stated, "Your son is a star of first rank."

But 20-year old Nikola was mortified when his father made light of those hard won honors. In second year, Tesla came into conflict with his professor when he suggested that commutators would be unnecessary in the Gramme Dynamo.

Tesla lost the scholarship money as he became addicted to gambling. In third year, he did not even sit for the examination. He severed all relations with family to hide the fact that he had dropped out. At age 22, without contacting anyone, Nikola moved to Slovenia in search of work.

His family thought that he had committed suicide but one year later,

In March of 1879, Milutin learned that his son was seen in Maribor, the second-largest city of Slovenia. He went to Maribor to beg his son to return home. Tesla refused.

street where Tesla lived in Maribor

Milutin was despaired. In April of 1879, he passed away aged 60. After hearing the news, Nikola returned home but too late though.

A sorrowful Nikola recalled, "My father wanted me to enter priesthood but in one of the sinking spells due to Cholera, which was thought to be the last, he rushed into my room. I still see his pallid face as he tried to cheer me up..

"Perhaps," I said, "I may get well if you will let me study engineering."

"You will go to the best technical institution in the world," he solemnly replied.

Nikola was lost and depressed especially after death of his father. He stayed home for few months. Then, he started teaching at his old primary school. He taught there until January 1880.


Next, he went to Prague and attended lectures in philosophy for a year. In 1881, Nikola moved again, this time to Budapest to work for Budapest Telephone Exchange. He was 25 years old.

In 1882, he was employed as electrician by Continental Edison Company in Paris to install incandescent lighting. The management took notice of his advanced knowledge and soon he was promoted.

"In 1884, I was brought in intimate contact with Edison. His mind was dominated by one idea, to leave no stone unturned and to exhaust every possibility. We experimented for days and nights, holidays not excepted."

During this time, Edison made an outstanding offer. In exchange for redesigning generators, Tesla was promised a hefty cash prize.

But he was taken advantage of as it turned out to be a practical joke. Therefore, in January 1885, a furious Tesla left note for Edison which read, "Goodbye to the Edison Machine Works."

For a brief while, Nikola Tesla remained jobless in America.

Then, with help from interested investors, Tesla founded a company in his own name, Tesla Electric Light & Manufacturing (1885). He worked for the rest of the year acquiring patents for improved design of DC generator which had gained recognition in the press.


But Nikola was not business-ready yet.

In 1886, the investors obtained control of the patents, renamed the company to Union County Electric Light & Manufacturing and left Tesla penniless in the process.

"My life seemed to me like mockery."

Yet, Tesla did not give up as he set about to create another company, this time with more caution, in 1887. He invented commutator-less induction motor in the same year. This innovative machine which ran on alternating current was patented by Tesla in May of 1888.

Soon, $15,000-a-year royalty deal was made for the new type of motor with Westinghouse Electric Company.

Induction motor by Tesla

But two years after signing the Tesla contract, George Westinghouse was in deep financial trouble. Also, at this time, Edison came out with all guns blazing against the alternating current movement, saying, "It is too dangerous. Direct current is safe."



In 1891, Westinghouse explained his situation to Nikola Tesla and Tesla agreed to release Westinghouse Company from the royalty payment.

Six years later, when all troubles sorted, direct current defeated, Westinghouse purchased Tesla's 1888 motor patent for a lump-sum of $216,000. The money made Tesla independently wealthy and gave him the time and funds to pursue his own interests.

Nikola Tesla went on to obtain around 300 patents in over 25 countries for his inventions. Tesla coil, remote control, induction motor, neon lamp, wireless telegraphy to name a few.

on the cover (1931)

Tesla died on 7 January in 1943 at the age of 86. He never married, did not have any children and devoted his life totally to the pursuit of knowledge and innovation.

"To me[Nikola Tesla], the universe is simply a great machine which never came into being and never will end and what we call 'soul' or 'spirit,' is nothing more than the sum of the functionings of the body. When this functioning ceases, the 'soul' or the 'spirit' ceases likewise".

Characteristics of Physical Law

Despite numerous limitations, we human beings are able enough to study as well as appreciate the grandeur of the universe. Our great journey of determining scientific laws began as we understood the regular repetitions of the day and night, the annual cycle of seasons, the eclipses, the tides, the volcanoes, the rainbow and so on.

What is scientific law?

A scientific law is verbal or mathematical explanation that describes some phenomenon of the natural world. For example, Newton's law of gravity, which states that every particle attracts every other particle in the universe with a force directly proportional to the product of their masses and inversely proportional to the square of the distance between their centers. But the law itself does not explain why the phenomenon exists or what causes it: that is really the job of theory, in this case, Einstein's theory of general relativity.

The scientific law is factual and should not be confused with logical truth. For example, "boiling point of water is 100 degrees celsius" is a law whereas "every number has a double" is logical truth and not really a law.

Constant over space and time

The same laws which apply here on earth also apply to the rest of the universe. For example, Galileo's law of falling bodies was tested on the moon by astronaut David Scott in 1971.

This is simple and yet beautiful truth, that the laws of nature are universally valid. There are no laws of nature that hold just for the planet earth or the Andromeda Galaxy, for that matter.

In addition, the laws of nature do not change as time progresses. There is a joke which goes something like this, "Before Newton discovered gravity, all things could fly." That is so not the case; there are no laws of nature that hold just for the eighteenth century or just for the Mesozoic Era.

Same for animate and inanimate

The laws are same for living beings and for inanimate objects. There is no evidence yet that what goes on in living creatures is necessarily different, so far as the physical laws are concerned, from what goes on in non-living things.

For example, conservation of angular momentum is a fundamental law of nature. A rotating ballerina spins faster when drawing her arms in.

Similarly, the earth and other planets revolving around the sun obey the law of conservation of angular momentum, which is why, when a planet is nearer to the Sun, the orbital speed increases and when it is farther away, it slows down.

Simple in nature

Eminent kiwi physicist Ernest Rutherford used to say, "it should be possible to explain the laws of physics to a barmaid." But even though the laws themselves are so simple, their implications are far and wide.

For example, Newton's third law of motion is simply, "for every action there is equal and opposite reaction", and yet it is noticeable in many instances of life such as in walking, swimming, recoiling of gun, and most importantly, rocket propulsion.

Similarly, Newton's second law of motion is just, F=ma, but it made possible the industrial revolution. Steam engines, locomotives, factories, machines, all of it due to the mechanics set into motion by the second law of motion.

Same in uniform motion

If we have an experiment working in a certain way and then take the same apparatus, put it in a car, and move the whole car, plus all the relevant surroundings, at a uniform velocity in a straight line, then so far as the phenomena inside the car are concerned, there is no difference.

Unification of laws

Scottish physicist James Clerk Maxwell took a set of known experimental laws such as Faraday's Law, Ampere's Law and unified them into a symmetric coherent set of equations known as Maxwell's equations.

Maxwell's equations are also laws just like the law of gravity. They govern the behavior of electric and magnetic fields. Also, light itself is an electromagnetic wave. Therefore, Maxwell's equations have in a way unified three separate phenomena, electricity, magnetism and optics, into one.

A similar type of unification occurred in the early part of the 20th century. The laws of conservation of energy and conservation of total mass were proven to be equivalent by German physicist Albert Einstein in a simple equation, E=mc^2.


These unifications are possible because the laws of physics are symmetrical in nature. Two or more distinctly appearing natural phenomena appear to be governed by just one simple law. Thus, one day, we may be able to find an ultimate law of physics that may explain everything.

Renowned American physicist Richard Feynman had famously said, "God is always invented to explain those things that you do not understand."

Throughout history, man has credited god for this or that phenomena. For example, early Greeks believed that lightning was a weapon of Zeus. Now, when you finally discover how something works, you get some laws which you're taking away from god; you don't need god anymore.

Thus, "what one man calls god, another calls the laws of physics," or in other words, to have an understanding of the physical laws is in a way a liberation from all superstition.

How To Study Physics By Using Feynman Technique

Richard Feynman was one of the world’s greatest scientists who won a nobel prize for physics in 1965. But we recognize him more as an outstanding teacher, a story-teller and an everyday joker whose life, was a combination of his intelligence, curiosity and uncertainty.

Feynman was once asked in an interview whether an ordinary person could understand physics like him. After a brief pause, "of course!", he replied candidly. "I was an ordinary person who studied hard."

In this post, you will learn to study physics by using the Feynman Technique, a method involving four easy steps, which was designed to help you understand concepts you don't get and to remember stuff you've already learned.

1. Write

This is a no-brainer. Always write down everything you know about the topic on a notebook page. Add examples and illustrations in your notes whenever possible.

Why is it important to write? Because writing anything down makes us remember it better. This is also the reason why many life coaches advise to pen down our goals.

2. Explain

Describe whatever you have learned to an empty room. This step will not only test memorization but also help you to become a better teacher.

Yes, many of you may not want to go into the teaching profession but it is a good practice to convey your learning in loud words. Remember, teaching is a powerful tool to learning.

3. Analyze

There is a famous saying which many attribute to Feynman, "If you cannot explain it simply, you do not understand it", which is fairly obvious.

Did you teach it well? Where is the gap in your understanding? Identify it. Then, revisit your notes for revision.

Revision often increases your confidence because the gap in your understanding is reduced. You may even want to rewrite your notes in a more simple language than before.

4. Repeat

Because of revision, you should have a better grasp of the subject. So gather one of your friends and explain the topic once again, to him/her. This step is powerful because when one teaches, two learn.

At the end, take feedback from your friend as that might help in understanding any remaining gaps. Did you know that Professor Walter Lewin, famous for his physics videos on YouTube, used to teach at least five times to an empty hall, before actually taking the class?

Summing up

Feynman had once said, "I don't know what's the matter with people: they don't learn by understanding; they learn by some other way, by rote or something. Their knowledge is so fragile!"

But if you follow what is known as the Feynman Technique, as described here, you will be able to learn more efficiently and firmly. It is a tried and tested method so please share this post with fellow students.