Steven Weinberg's four tips for aspiring scientists

Steven Weinberg (1933-2021) was an American physicist who worked alongside Pakistani physicist Abdus Salam to unify electromagnetic and weak interactions in 1967. He shared the Nobel Prize in physics for the same work later on.

Weinberg was not only famous as a scientist but also for his outspokenness and elegant writings outside of science. He thus made important contributions to history as well as to politics. Following are his 4 advices for aspiring scientists.

1. You don't have to know everything

Weinberg's first golden lesson is specialization. He wrote for Nature in 2003: When I received my undergraduate degree, the physics still seemed to me a vast, unexplored ocean.

How could I begin any research of my own without knowing everything that had already been done? Weinberg recalled.

A lot of the times students are so overwhelmed or even excited by that vastness that they fail to go forward. Weinberg says: You don't have to know everything because I didn't when I got my PhD.

2. Aim for rough water

When Weinberg was a professor, a student came up to him and said that he would pick general relativity rather than the area Weinberg was working on - particle physics.

Obviously as the teacher Weinberg was disappointed. When asked to explain, the student replied: The principles of general relativity are well known, while the particle physics is an incoherent mess.

Weinberg quipped: That makes it all the more worthwhile because in particle physics creative work can still be done.

So, according to Professor Steven Weinberg, it would be a lot better to aim for the rough water especially while you are able to swim in that vast, unknown ocean. For who knows what might be out there?

3. Forgive yourself for wasting time

This is his most beautiful advice: Forgive yourself for your failures. Forgive yourself for wasting time on the wrong problems. Whatever can go wrong will go wrong, but there will always be silver lining in the end.

Weinberg cites an example in history... When scientists were trying to prove existence of the Ether they didn't know that they were working on the wrong problem. It nonetheless helped Albert Einstein in 1905 to realize the right problem to work upon.

Weinberg adds: You will never be sure which are the right problems most of the time that you spend in the laboratory or at your desk. But if you want to be creative, then you will have to get used to wasting your time.

4. History of science

Final tip to aspiring scientists: Study the history of science as it will make your work seem more worthwhile to you. Because, a work in science may not yield immediate results, but to realize that it would be a part of history is a wondeful feeling.

As you will learn its rich history, you will come to see how time and time again - from Galileo through Newton and Darwin to Einstein - science has weakened the hold of religious dogmatism: Weinberg adds.

In one interview, when asked whether he believed in God, Weinberg replied... If by God you mean a personality who is concerned about human beings, who did all this out of love for human beings, who watches us and who intervenes, then I would have to say in the first place how do you know, what makes you think so?

8 times when Nikola Tesla was wrong about physics

Nikola Tesla was a great Serbian-American engineer who played the major role in perfecting and promoting alternate current. He was also a visionary who predicted smartphones, renewable energy and creation of artificial Suns, much before time permitted.

However, it is surprising that Tesla sometimes took anti-science as well as anti-mathematics positions. Several of his views about the world were particularly pseudoscientific. So in this post, let us look at 8 instances when even the Genius Nikola Tesla was wrong.

On electrons

Tesla did not agree with the theory of atoms being composed of smaller subatomic particles. He thought that there was no such thing as an electron creating an electric charge and that it had nothing to do with electricity.

However, not only did the electron get discovered but also its properties and effects were measured by physicist J.J. Thomson at the start of the twentieth century. Without electron, technologies like the television couldn't exist.

On relativity

According to Nikola Tesla, Einstein's 1915 theory of general relativity was wrong. He commented in 1932: "I hold that space cannot be curved, for the simple reason that it can have no properties. It might as well be said that God has properties. He has not."

In 1935, Tesla told The New York times: "Einstein's relativity work is a magnificent mathematical garb which fascinates, dazzles and makes people blind to the underlying errors. The theory is like a beggar clothed in purple whom ignorant people take for a king."

In 2004, the gravity probe-b satellite was launched to measure the curvature due to Earth. Its data was analyzed by the Stanford University and it indeed confirmed Einstein's theory to a high degree of accuracy in 2011.

Furthermore, without relativity, the GPS would fail in its navigational functions and Google maps couldn't work to pinpoint precision.

On mathematics

Nikola Tesla said in 1934: "Today's scientists have substituted mathematics for experiments, and they wander off through equation after equation and eventually build a structure which has no relation to reality."

That may be true, although mathematics and experiments are both fundamental to scientific progress. There cannot be one without the other, especially in the field of physics.

At the same time in Europe, Dirac was trying to find an equation to unify quantum mechanics and special relativity. He predicted the existence of antimatter in doing so, which was discovered in 1932.

Even 16th century Galileo Galilei had a high regard for mathematics, when he said: Philosophy is written in mathematical language; without it one wanders in vain through a dark labyrinth.

On atomic energy

Tesla told The New York Times in 1931: "The idea of atomic energy is illusionary. I have preached against it for twenty-five years but there are still some who believe it to be realizable."

Because, as mentioned before, he did not trust the theory of subatomic particles. So according to Tesla, atoms were immutable – meaning that they could not be split or changed in any way.

Two years after Tesla's death in 1943, not only did the humankind split the atom, they also used it to end the World War II. Although it began a nuclear arms race and a call for disarmament – well that is another story in itself.

Today, atomic energy is a source of nuclear power – as predicted by physicist Lise Meitner – which is in turn used to generate heat and electricity. Moreover, scientists are also working on a large-scale fusion project called ITER for future electricity generation.

On EM waves

German physicist Henrich Hertz demonstrated the accuracy of Maxwell's equations when he successfully generated electromagnetic waves in laboratory.

Because Tesla did not have the mathematical advantage, he relied completely on experiments and his own experiments led him to erroneously believe that Hertz and Maxwell were wrong.

In one 1891 lecture, Tesla expressed openly his disagreements with Hertz – which is anyway healthy for the sake of scientific progress.

But over the next few years, several groundbreaking evidences were collected in the favor of Maxwellian electromagnetism.

In 1898, Tesla himself developed a radio based remote-controlled boat and yet till 1919 he did not believe in the existence of EM waves and in the theories developed by Maxwell and Hertz.

On wireless electricity

Tesla was a great visionary but his vision was not always practical. After perfecting alternate current technologies, Tesla wanted to make a new revolutionary change - render wires useless!

At first, Tesla decided to transmit electricity through air but rejected the idea later on. In 1902, Tesla completed the Wardenclyffe Tower to tranfer electricity via ground.

However, engineers pointed out that currents once injected into the ground would spread in all the directions, quickly becoming too diffuse to be usable over long distances.

In addition to engineering and financial problems, the dangers of wireless electrical power to nearby wildlife was not taken into account by Tesla. Thus, the Wardenclyffe Tower project had to be abandoned.

During the same time, Italian engineer Guglielmo Marconi - who unlike Tesla, believed in and worked with electromagnetic waves, succeeded in the wireless transmission of information, rather than electricity.

On science

Although Nikola Tesla was a brilliant engineer and inventor, he sometimes delved into pseudoscientific ideas which had no basis in reality and lacked experimental data – a quality he admired.

For example, Tesla once said: A single ray of light from a distant star falling upon the eye of a tyrant in bygone times may have altered the course of his life, may have changed the destiny of nations.

That thought, although poetically is beautiful, has no scientific weight. Distant stars and planets and their motions have no measurable effects on people. What changes destiny of nations is politics and the king's advisor would have had far greater impact than light of a far away star.

On radioactivity

In 1903, Marie Curie, Pierre Curie and Henri Becquerel won the Nobel Prize in physics for discovering evidence for radioactivity.

However, Tesla was not convinced since he did not believe that the atom was divisible and that it had internal forces and subatomic particles.

According to him, the phenomena of radioactivity was not the result of forces within the radioactive substance but by the rays emitted by the Sun.

He told The New York Times in 1931: If radium could be screened effectively against this ray it would cease to be radioactive.

Summing up

Nikola Tesla was a genius inventor and explorer whose work ushered the electrical revolution that transformed daily life. Einstein wrote to Tesla: As an eminent pioneer in the realm of high frequency currents... I congratulate you on the great successes of your life's work.

But at the same time Nikola Tesla was also human – jealousy, denial and frustration, played a big role in his professional life.

His frustration with advanced mathematics led him to incorrectly conclude that Maxwell's equations and relativity were wrong.

His denial of modern science left him too far behind his contemporaries – Marconi, Braun, Bose – in his ability to contribute to the wireless communication.

Surely, Tesla did achieve what others could only dream of. But the point is, not to put Tesla on pedestal, or build conspiracy theories in his favor, as many fans would want to do. It does not do justice to Tesla's brilliance.

10 TV Shows That Physics Students Will Enjoy

While there are several movies and documentaries that appeal mainly to science students, there are not a whole lot of TV shows that a science lover can truly enjoy. Thus, here is a list of tried and tested TV shows that physics students will find interesting.

1. Steins; Gate

If you are into science of time travel, then this show is for you. (Plus, there is a lot of action as well.) In the anime, 11 possible theories of time travel have been touched upon - since one of the protagonists is a theoretical physicist.

The show has also made use of grandfather paradox, multiverse theory and separate timelines. You will be intrigued right from the beginning due to eccentricities of the main character - the show is brilliant in every manner possible.

2. Big Bang Theory

Of course, this is a well known comedy show in which three physicists and an engineer grapple with the complexities of life - especially upon the entry of a girl in their lives.

There will be occasional quizzes, cosplays - such as Sheldon dressing up as Doppler Effect - demonstrations and explanations - like Leonard explaining centripetal force.

Many renowned celebrities such as Stephen Hawking, Elon Musk, Neil deGrasse Tyson and Steve Wozniak have acted in the show. In fact, Hawking made multiple appearances.

So, overall, it is a fun show for every science student. The first four seasons especially keep the scientific aspect of the show intact. You can watch it on Amazon Prime.

3. Star Trek

In Star Trek, we follow the adventures of a space crew whose mission is to explore strange new worlds in the galaxy - as a mater of fact in the entire universe - to be honest. It is a show loved especially by physicists and astronauts.

So much so that physicist Lawrence M. Krauss wrote a book titled: Physics of star trek based upon the series. In one episode of The Next Generation Newton, Einstein and Hawking are filmed playing poker with Data.

Many technological marvels such as matter-antimatter generation, transporter, androids, cloaking devices, etc. have been mentioned and made use of in the show. You can catch it on Amazon Prime.

4. Doctor Who

Time travel is just one of the many themes which are included in Doctor Who. The show has pulse-pounding action that will put you on the edge of your seat, but it also makes you think, such as on the nature of reality, consciousness, etc.

In 2014, physicist Brian Cox hosted a lecture on the science of Doctor Who. Biologist Richard Dawkins made an appearance in one episode. Its eminent writers include Russell T Davies, Steven Moffat and Neil Gaiman.

The show's protagonist frequents between the past and the future. Thus, stories of various historical figures such as William Shakespeare, Ada Lovelace, Rosa Parks, Charles Babbage, Vincent Van Gogh, etc. have been covered in the show.

As far as tomorrow is concerned, writers have shown dystopian future on many occasions and technologically superior space faring human civilization as well.

Apart from science and science fiction the show has also ventured into supernatural, horror and thriller genre. This makes Doctor Who the most versatile science show of all time. You can watch it on Amazon Prime.

5. Young Sheldon

If you're a budding scientist who enjoys family comedies then Young Sheldon on Amazon Prime is for you. As the title suggests the show is based on stories from Sheldon Cooper's childhood. Its themes include science, education, adolescence, family and religion.

6. Dr. Stone

This show is set in post-apocalyptic Earth when humankind has lost most of its technology and resources to Stone. Our genius protagonist is on a mission to redevelop items of everyday use. So it's like watching Bear Grylls in Man VS Wild except that it's Bill Nye in place of Bear Grylls.

7. Black Mirror

It is a dystopian science fiction show in which we delve into the relationship between science, society and technology; that how technology has reduced our freedom, diminished our privacy, etc. If you are accepting of dark humor, satire and dystopia then this is for you.

8. Rick and Morty

This is animated TV show in which we follow the adventures of mad scientist Rick Sanchez and his grandson Morty Smith. The main characters and themes of the show seem to be inspired by Back to the future and Doctor who respectively.

Stories revolve around various scientific topics such as multiverse theory, alien life, mind bending parasites, robots, etc. while also taking into account philosophies such as cosmicism and nihilism.

9. Battlestar Galactica

This action packed show is based upon the bittersweet relationship between humans and artificial intelligence. What does it mean to be human? Its main theme is that, along with a desperate search for home planet - such as Earth - because humans are on the run for their lives after losing war against the great warrior robots, Cylons.

10. The Expanse

Real world science sets this science fiction apart from all the rest. The showrunner Naren Shankar was once an engineer by profession; he also has a PhD. Like all Indians deciding not to be an engineer anymore he then ventured into writing.

The Expanse which you can watch on Amazon Prime is a beautiful combination of space engineering and fiction. It has some of the best physics-based spaceflight and combat and an engaging story as well, according to one viewer.

10 Nobel Prize Winning Families In Science

The Nobel Prize is the most prestigious award given for intellectual achievement in the world. While there have been several controversial snubs, few have also gone on to win multiple prizes. This, is a list of 10 famous Nobel laureate families of the world.

Curie family

You may already know that Marie Curie and Pierre Curie have jointly won the Nobel Prize in physics. Their daughter, Irène Joliot-Curie received the Prize in chemistry, sharing it with her husband Frédéric Joliot-Curie.

Marie Curie was awarded one more Prize for work done in chemistry thus taking their family total to five Nobel Prizes.

Niels and Aage Bohr

This father and son duo has won the Nobel Prize for physics in 1922 and 1975 respectively. Niels Bohr was awarded for his services in the investigation of atomic structure and Aage Bohr won for describing the structure of atomic nucleus.

Raman and beyond

In 1930, C.V. Raman became India's first Nobel laureate in physics. His nephew Subrahmanyan Chandrasekhar was awarded in 1983 for explaining the evolution of stars. In 2009, another Tamilian Venki Ramakrishnan won the Prize only this time in chemistry.

Thomson family

J.J. Thomson got the 1906 Nobel Prize in physics for his discovery of electron, the first subatomic particle to be found. His son, George Paget Thomson was recognized by the Nobel Committee in 1937 for showing that electron behaved like a wave.

Arthur and Roger Kornberg

Roger was only 12 years old when he saw his father Arthur Kornberg receive the most coveted Prize in 1959. Then, 47 years later, Roger won the Nobel Prize in chemistry for explaining how information is copied from DNA to RNA.

Euler family

Hans von Euler-Chelpin, distantly related to mathematician Leonhard Euler, was a biochemist who won the 1929 Nobel Prize in chemistry. His son Ulf von Euler was a physiologist who won the Prize in medicine for work done on neurotransmitters.

Manne and Kai Siegbahn

This father and son duo was an expert on spectroscopy. Manne Siegbahn won the Nobel Prize in physics for pioneering work done in x-ray spectroscopy. Whereas his son Kai Siegbahn won the same Prize for developing a new method of electron spectroscopy.

Bragg family

William and Lawrence Bragg were jointly awarded the 1915 Nobel Prize for their services in the analysis of crystal structure by means of x-rays. Lawrence is thus far the youngest ever laureate in physics. The father-son duo also have a crystal named after them – Braggite.

May-Britt Moser and Edvard Moser

The Curies are not the only couples that have won the Nobel Prize. In 2014, Edvard Moser and May-Britt Moser received the Prize in medicine for the discovery of grid cells. These are neurons which provide a coordinate system to the brain and thus help an animal navigate in space.

Carl Ferdinand and Gerty Cori

Another Nobel Prize winning couple: Gerti Corie was the third woman to win a Nobel Prize in science. The biochemist duo shared the 1947 Prize in medicine for their discovery of glycogen.

7 Lessons To Learn From Richard Feynman

Richard Feynman (1918–1988) was a Nobel Prize winning American physicist whose life was a combination of his intellect, uncertainty and a childlike curiosity.

Although he was a late talker and did not speak until after his third birthday, we know Feynman best as the chatty one.

His life is a story of constant growth: First, as a student, then as an eminent physicist and ultimately as a beloved teacher. Following are seven motivating lessons from Feynman's life.

1. Pursue a hobby

Feynman has said: "Fall in love with some activity and do it. Because, nobody ever figures out what life is all about and it doesn't matter." Feynman used to draw on canvas in spare time. He also learned Portuguese just so he could impress his colleagues in Brazil.

2. Explore the world

Everyone wants to win but no one wants to play the game. That's what Feynman meant when he said: "Everything is really interesting if you go into it deeply enough." Try new things and work as hard and as much as you want to on the things you like to do the best.

3. Carve your own path

The essence of Feynman's autobiography is: "Don't think about what you want to be, but what you want to do." Don't care about what others think. However, keep up some kind of a minimum, such as a degree, so that society doesn't stop you from doing anything at all.

4. Keep learning

Feynman has said: "It is important to admit when you do not know." There is no shame in not knowing. The only shame is when you pretend that you know everything. So, read as many books as you can. Be as practical as you need to be.

5. You only live once

Feynman was the first to profess this popular life mantra when he said: "Of course, you only live one life. So, make all your mistakes now, and learn what not to do." Thus, life is a process of constantly growing up.

6. Blind belief is dangerous

Feynman mentions in his autobiography: "Have no respect whatsoever for authority; forget who said it and instead ask yourself, Is it reasonable?" In other words, do not blindly believe anyone and make up your own mind about the world.

7. Enjoy the process

Feynman did not become a scientist for honors or recognition. He said: "My interest in science is to simply find out more about the world." So, no matter what you choose to become in life, do it because you love it deeply.

Top 10 Important Equations In Physics

These simple-looking equations went on to have great consequences and applications in science, society and technology. Let us take a look at the ten most influential formulae in physics (in no particular order) which have changed the course of history.

Second law of motion

The force, often intuitively described as push or pull, is actually the cause of acceleration in a moving particle. Without it coming from any external agency, the particle cannot undergo change in the way it goes. Newton defined the force formally in 1686 in the famous equation, F=ma.

It tells you how powerful an engine has to be in order to pull a car, how much thrust required to lift a rocket, how far a cannonball flies and so on. But more importantly, the equation helped debunk the Aristotelian beliefs which had remained unchallenged for thousands of years.

According to Aristotle, force is necessary to keep an object going. Why otherwise would a ball rolling on the ground eventually stop? Because, Aristotle said, it isn't pushed anymore, that's why.

Then, in the 17th century, Italian scientist Galileo Galilei explained, with experiment, "The ball stopped due to the ground being rough and had it been sufficiently smooth, the ball would roll forever. No force required!"

Newton said further, that the state of rest or uniform linear motion both imply zero acceleration. Thus, the particle will remain in place or keep going at the same rate and it will maintain itself in the state in which it's been until of course when acted upon by external force.

Energy-mass relation

It followed from the special theory of relativity that mass and energy are both but different manifestations of the same thing. The mass of a body is a measure of its energy content. If 1 gram of mass is converted into energy, it'd be 90 trillion Joules. This is equal to the energy emitted by a 100 watt light bulb for 30,000 years!

It is important to understand that Einstein's most famous equation is not his major work. The formula is just so well-known because of its association with the atomic bomb. Einstein himself had said, "If I had foreseen Hiroshima and Nagasaki, I would have torn up my formula in 1905," despite him having played a minor role in the Manhattan Project.

Uncertainty principle

Formulated by Werner Heisenberg in 1927, uncertainty principle is one of the cornerstones of quantum mechanics. The equation single-handedly ended the classical determinism, meaning, that in the realm of infinitesimal atoms, chance has its play and the drama of existence is not absolutely predestined in character.

In its most familiar form, it says that the more precise the measurement of position, the more imprecise the measurement of momentum, and vice-versa. Thus, one can never know with perfect accuracy both of those two important factors which determine the movement of one of the smallest particles, its position and its velocity, at the same instant.

The uncertainty principle was immediately rejected by leading physicists of the time, including Albert Einstein. There, Niels Bohr did try his best to convince Einstein that the uncertainty relation is fundamental law in physics. Einstein still refused, and they agreed to disagree. By 1933, the political situation became much worse in Germany, and Einstein moved to the United States.

In 1954, Heisenberg visited Einstein's house in Princeton. They talked only about physics, but Einstein's position on the principle hadn't changed. In 1955, Einstein passed away leaving Werner Heisenberg disheartened that he had failed to get Einstein's endorsement of his uncertainty relation.


Although Einstein and others objected to Heisenberg's and Bohr's views, even Einstein had to admit that they were indeed a logical consequence of quantum mechanics. But for Einstein, something still was missing and the quantum mechanics was incomplete, "I am convinced that god does not throw dice," he claimed metaphorically.

Heisenberg, supported by Bohr, Pauli, Schrödinger and others, maintained until his death that quantum uncertainty is not inaccuracy of the measurement, it is inherent in quantum phenomena. It leads to probabilistic and not deterministic outcomes.

Maxwell-Faraday equation

In 1831, as the story is usually told, the prime minister or some other senior politician was given a demonstration of electromagnetic induction by Faraday. When asked, “What good is it?” Faraday replied: “What good is a newborn baby?” Fifty years passed before electric power really took off as envisioned by Faraday.

Generators and motors both make use of Faraday's Law. The equation by Maxwell became the foundation of power generation hence making Faraday the father of electricity. Maxwell said of Faraday, "He is, and must always remain, the father of that enlarged science of electromagnetism."

Dirac equation

Symmetry is the keyword of physics and Dirac used it perfectly in 1928. He developed an equation that explained spin number as a consequence of the union of quantum mechanics and special relativity. The equation also predicted the existence of anti-matter, previously unsuspected and unobserved, and which was experimentally discovered in 1932.

This accomplishment has been described on par with the works of Newton, Maxwell, and Einstein before him. Dirac even speculated that there may also be mirror universe of anti-particles, thus becoming a source of inspiration for science-fiction writers. Dirac was also equally famous for his contribution to quantum electrodynamics, which described how electric and magnetic forces would work on the scale of things smaller than atoms.

Law of entropy

The famous inequality which says that when energy changes from one form to another form, or when matter moves freely, the disorder in a closed system increases. According to renowned astronomer Arthur Eddington, "The law that entropy always increases, holds, I think, the supreme position among the laws of nature."

The concept of the second law of thermodynamics applies not only to internal combustion engines used in our cars, motorcycles, ships and airplanes but also to explain the processes of life, when considered in terms of cyclic processes.

The second law also has profound consequences for the universe in large scale. Imagine being shown a video clip of a cup being dropped and breaking. You'd clearly be able to tell whether the video was being played backward or forward, from the flow of entropy.

Similarly, if the movie of our universe is played backwards, the universe would be getting more and more ordered, like the cup, and when played forward, we'd expect it getting disordered, like the pieces of broken cup.

Einstein field equations

Einstein's equations led to the fusion of the three dimensions of space and the one dimension of time into a single four-dimensional spacetime. The expression on the left hand side of the equation represents the curvature of spacetime. The expression on the right is the energy density of spacetime. The equation dictates how energy determines the curvature of space and time.

The cosmological constant term (Λ) was introduced by Einstein to allow for a universe that is not expanding or contracting. This effort was unsuccessful because in 1929, astronomer Edwin Hubble discovered evidences for an expanding universe. Einstein was invited by Hubble to see for himself that the universe indeed was changing.

As a result, Einstein abandoned the cosmological constant in the equation, calling it the biggest blunder he ever made. So from the 1930s until the late 1990s, most physicists assumed the cosmological constant to be equal to zero. But, recently improved astronomy techniques have found that the expansion of the universe is accelerating implying the non-zero value of the constant.


Why are the Einstein field equations important in physics? Firstly, because they unify the two concepts of space and time, previously considered separate by the limitations of our intuition, into one spacetime. Just like Maxwell had unified electricity and magnetism into electromagnetism in the 19th century.

Secondly, they describe – not the force – but the fundamental "interaction" of gravitation as a result of spacetime being curved by energy (mass too is energy from Einstein's energy-mass equivalence).

Although Newton did give the formula to calculate the magnitude of gravitational force between any two bodies of mass separated by a distance, he didn't quite explain the cause of gravitation in the first place.

Wave equation

The single-dimensional wave equation has a scalar function (u) of one space variable and one time variable since waves propagate in space, and in time also. This equation was first written by French mathematician Jean le Rond d'Alembert, hence it's sometimes also called the d'Alembert's equation. Swiss mathematician and physicist Leonhard Euler wrote it in three dimensions in 1707.

We are constantly surrounded by waves, whether perceptible to us or not, they are always there. Like when you play a guitar or drop a stone into a pond. The wave equation isn't as elegant as others on this list but it is groundbreaking as it's been applied to sound waves (and instruments), waves in fluids, waves in earthquakes, light waves, quantum mechanics and general relativity.

Planck's equation

This formula is responsible for the birth of quantum mechanics, also television and solar cells. Leading German physicist of the time Max Planck postulated in 1900, that energy was quantised and could be emitted or absorbed only in integral multiples of a small unit, which he called "energy quantum".

Einstein extended Planck's idea in 1905 when he introduced the concept of "light quantum", the particle of light, or photon. Thus, the electromagnetic radiation wasn't continuous like a wave but isolated in the packets of light, Einstein proposed.

Planck had simply introduced the equation as a trick to solve a problem with black body radiation, but Einstein envisioned it to be more. In 1887, experimenter Heinrich Hertz stumbled upon the photoelectric effect for the first time; the emission of electrons when light of specific frequency hit a material.


The phenomenon of photoelectric effect remained largely unexplained, even with the wave theory of light, until the arrival of Planck-Einstein relation in 1905. Einstein described it in terms of particle-particle interaction between the photon and electron. He said, "...below some critical frequency, no photon has enough energy to knock an electron free."

This means that if a photosensitive material requires photons of blue light to emit the electrons, which is the characteristic of the material, then the photons of green or yellow light won't be able to knock the electrons out of the material.

The characteristic energy or work-function of the material is absorbed, to loosen the bonds, and then the remainder of the energy is observed as kinetic energy of the free electron. Einstein's clarification was consistent with the law of conservation of energy. He was recognized with Nobel Prize in physics for his explanation of the photoelectric effect (and not for energy-mass relation or relativity).

Planck said his introduction of "quantum" in 1900 was an act of desperation but when Einstein adopted it and gave it meaning, a whole new debate had started and the old laws were swept away within a decade or so. Einstein who himself was accountable for it refused to endorse the new quantum revolution.

The discovery by Planck and Einstein became the basis of all twentieth-century physics, without which, it would not have been possible to establish a workable theory of molecules and atoms and the energy processes that govern their transformations.

Schrödinger's equation

In his 1924 doctoral thesis, French physicist Louis de Broglie proposed, that just like light has both wave and particle properties, electrons must also possess wave-like properties, in order to support the energy-matter symmetry. Two years later, in 1926, Austrian scientist Erwin Schrödinger published an equation, describing how the matter wave should evolve in space and in time.

Just like Newton's equations are used to calculate how a football behaves when kicked, you use the Schrödinger's equation to calculate the behaviour of electron in the orbit of an atom. More generally, it is used for many calculations in quantum mechanics and is also fundamental to much of the modern technology, from lasers to transistors, and the future development of quantum computers.