15 Famous Physicists Who Were Agnostic

The word agnosticism was first publicly coined in 1869 by Thomas Huxley, a British biologist and champion of the Darwinian theory of evolution. He coined it as a suitable label for his own position. Following is a list of 15 physicists who were agnostics.

John Bardeen

Two time Nobel Prize winner in physics, first for his pioneering invention of the transistor, and second for the theory of superconductivity, American physicist John Bardeen, was an agnostic by choice.

He was once taken by surprise when an interviewer asked him a question about religion. "I am not a religious person," he said, "..and so do not think about it very much." But then he went on in a rare elaboration of his personal beliefs.

John added, "Science is a field which grows continuously with ever expanding frontiers but I feel that unlike religion it's never been done to give you the ultimate purpose in life. With religion, however, one can get some answers on faith. Most scientists, I think, leave these questions of life open and perhaps unanswerable, but they do abide by a code of moral values."

John was resolutely agnostic throughout his life.

J.C. Bose

Sir Jagadish Chandra Bose was an Indian biophysicist who invented the crescograph, a device that could detect very small motions within plant tissues. With this instrument, he showed for the first time, that plants also felt joy and pain.

Bose believed agnosticism to be the real essence of science and scientific method. A man shall not say he knows or believes that which he has "no scientific grounds" for professing to know or believe. He laid the foundations of "Basu Bigyan Mandir" (Bose's temple of scientific knowledge) in Kolkata, West Bengal.

Bose had famously said, "Not mere imagination and belief, but observation and experiment are the ultimate way of gaining knowledge or reaching the goal of acquiring truth."

Marie Curie

Two time Nobel Prize winner, one in physics and the other in Chemistry, first and only woman to achieve so, Madame Curie was an agnostic, from an early age. Her father Władysław Skłodowski was an atheist while her mother Bronisława Skłodowska a devout Catholic.

Her husband (also Nobel Prize winning physicist) Pierre Curie was an atheist. Neither wanted a religious service for their marriage ceremony. She wore a dark blue outfit, instead of a bridal gown, which would be worn by her in the laboratory for years to come.

In her final years, Marie advocated actively to encourage scientific temper in the general public, "Nothing in life is to be feared, it is only to be understood. Now is the time to understand more so that we may fear less," she would say.

Edwin Hubble

American astrophysicist who played a pivotal role in establishing the fields of extragalactic astronomy and observational cosmology. Hubble's most brilliant observation was that the red shift of galaxies was directly proportional to the distance of the galaxy from earth.

He said, "We do not know why we are born into the world, but we can try to find out what sort of a world it is, at least in its physical aspects." His life was dedicated to science and the objective world of phenomena.

When a friend asked Hubble about his beliefs, he replied, "The whole thing is so much bigger than I am, and I cannot understand it, so I just trust myself to it; and forget about it." Hubble remained an agnostic until his death.

Freeman Dyson

British-American theoretical physicist, who is famous for his work in quantum electrodynamics, solid-state physics and astronomy. Dyson was raised in what he has described as a “watered-down Church of England Christianity.” But he identifies himself as an agnostic.

He once said in a speech, "Science and religion are two windows that people look through, trying to understand the big universe outside, trying to understand why we are here. The two windows give different views, but they look out at the same universe."

"Both views are one-sided, neither is complete. Both leave out essential features of the real world. And both are worthy of respect. But trouble arises when either science or religion claims universal jurisdiction, when either religious or scientific dogma claims to be infallible," he added.

Albert Einstein

Many believers refer to some of his quotes and thus try to claim the greatest scientist of the 20th century as one of their own. However, Einstein also had famously said, "I feel that the idea of a personal God is a childlike one."

He added in 1941, "I was barked at by numerous dogs who are earning their food guarding ignorance and superstition for the benefit of those who profit from it. Then there are the fanatical atheists whose intolerance is of the same kind as the intolerance of the religious fanatics and comes from the same source."

In 1949, Einstein was prompted once again to describe his religious beliefs, "I prefer an attitude of humility corresponding to the weakness of our intellectual understanding of nature and of our own being," he said, "you may call me an agnostic, but I do not share the crusading spirit of the professional atheist."

C.V. Raman

Sir Chandrashekhara Venkat Raman was influential in the growth of science in India. He was the recipient of the Nobel Prize in Physics for the discovery of the "Raman Effect" which has its use in chemistry to provide a structural fingerprint by which molecules can be identified.

Raman was born into an orthodox South Indian Brahmin family but his interests in physics kept him away from religious or spiritual activities. He avidly read Charles Bradlaugh, the English founder of the National Secular Society and Herbert Spencer, the English polymath who contributed to agnosticism.

Rosalind Franklin

She was a British biophysicist and x-ray crystallographer who made important contributions to the understanding of the fine molecular structures of DNA, RNA and Graphite. When asked about her beliefs, she replied, "Science is my religion."

Her lack of religious faith did not stem from anyone's influence, rather from her own line of thinking. She developed her skepticism as a young child. Her mother recalled that she refused to believe in the existence of God, and remarked, "Well, anyhow, how do you know He isn't She?"

She added, "I see no reason to believe that a creator of protoplasm or primeval matter, if such there be, has any reason to be interested in our insignificant race in a tiny corner of the universe." However, Rosalind did not completely abandon Jewish traditions.

Enrico Fermi

Italian physicist who is known for the development of the first nuclear reactor and for his contributions to the development of quantum theory and nuclear physics. Fermi was awarded the 1938 Nobel Prize in Physics for his work.

Although Enrico was baptised a Roman Catholic in accordance with his grandparents' wishes, his parents were not particularly religious. His attitude to the church eventually became one of indifference, and he remained an agnostic all his adult life.

Eugene Wigner

The Hungarian physicist was the recipient of the Nobel Prize in Physics in 1963 for his contributions to the theory of the atomic nucleus and the elementary particles, particularly through the discovery and application of fundamental symmetry principles.

Wigner's family was Jewish but not religiously observant and his Bar Mitzvah was a secular one. He told his Biographer about his religious views, "I liked a good sermon. But then religion tells people how to behave and that I could never do."

He added, "Clergymen also had to assume and advocate the presence of God, and proofs of God's existence seemed to me quite unsatisfactory. People claimed that God had made our earth. Well, how had He made it? With an earth-making machine?"

Carl Sagan

Famed American astrophysicist Carl Sagan was a renowned skeptic and agnostic who during his life refused to believe in anything unless there was physical evidence to support it.

His most well-known scientific contribution is research on extraterrestrial life, including experimental demonstration of the production of amino acids from basic chemicals by radiation. He was also known as "people's astronomer".

In reply to a question in 1996 about his religious beliefs, Sagan answered, "I'm agnostic." Sagan maintained that the idea of a creator God of the Universe was difficult to prove or disprove.

He also wrote, "Some people think God is a light-skinned male with a long beard, sitting on a throne somewhere up there in the sky, busily tallying the fall of every sparrow. Others, for example Einstein, considered God to be essentially the sum total of the physical laws which describe the universe."

Lisa Randall

She is an American theoretical physicist who works on the models of string theory in the quest to explain the structure of the universe. Her best known contribution to the field is the Randall–Sundrum model, first published in 1999. She has described herself agnostic.

In a 2006 interview, Lisa was asked whether or not she believed in God. She said, "Faith just doesn't have anything to do with what I'm doing as a scientist. It is nice if you can believe in God, because then you can see more of a purpose in many things."

"But even if you don't, though," she added, "..it doesn't mean that there's no purpose. It doesn't mean that there's no goodness. I think that there's a virtue in being good in and of itself. I think it's a problem that people are considered immoral if they're not religious. That's just not true."


Paul Dirac

He was rightfully declared the successor of Maxwell and Einstein when he worked on the reconciliation of general relativity with quantum mechanics. Dirac also predicted the existence of anti-matter for which he was given Nobel Prize in 1933.

He said in 1927, "We scientists have to be honest and must admit that religion is a jumble of false assertions with no basis in reality. The very idea of God is a product of the human imagination. Nowadays, when we understand stuff with so many natural explanations, we have no need for such solutions."

His wife Manci, (who was the younger sister of physicist Eugene Wigner), claimed, "My husband wasn't an atheist. In Italy, once, he said, "If there is a God, he has to be a great mathematician. He did say if."

Dirac explained why he was agnostic and not an atheist, "If physical laws are such that to start off life involves an excessively small chance, then there must be a god, and such a god would probably be showing his influence in the quantum jumps which are taking place later on."

"On the other hand," Dirac added, "..if life can start naturally on other planets (by chemical or biological means) and does not need any divine influence, then I will say that there is no god." Dirac remained agnostic throughout his life because the question of origin of life was not answered.


Murray Gell-Mann

He was an American physicist who received the 1969 Nobel Prize in Physics for his model of quark (an elementary particle which combines with itself to formulate heavier particles like proton and neutron).

Murray called life a complex adaptive system which produces interesting phenomena, "Life can emerge from physics and chemistry, plus a lot of accidents. The human mind can arise from neurobiology, and a lot of accidents," he said.

"People keep asking me", Murray went on, "...isn't there something more beyond what you have there? Presumably they mean something "supernatural" but anyway, there isn't; you don't need something more to explain something more."


Henri Poincaré

Jules Henri Poincaré was a French physicist and mathematician who's known for his work in various fields of physics such as optics, mechanics, thermodynamics and relativity. He also contributed to the theory of algebra and geometry.

He used to say, "To doubt everything or to believe everything are two equally convenient options; but both require sincere introspection." He wrote the book, "The value of science" in 1905, in which he had declared that the hypothesis of God is incomplete and imperfect.

Biography of Madame Curie

A leading figure in the history of sciences, Marie Curie was prohibited from higher education in her native Poland. Many years later, she became the first woman Nobel laureate. She remains the only person to win the most coveted prize in two different sciences. This is her story.

Childhood

Maria was born in 1867 in Warsaw (Poland) which was then part of the Russian Empire. She was the fifth and youngest child of well-known science professor Władysław Skłodowski. Her mother, Marianna Bronisława operated a reputed boarding school for girls in the big bustling city.

When Maria was seven years old, her eldest sibling died of typhoid and then three years later her mother lost the battle to tuberculosis. At the same time, Władysław was fired from his job due to pro-Polish sentiments and the family eventually lost all the savings.

In the middle of crisis, Władysław decided to join a low-paying teaching job. The Russian authorities at the school banned the usage of laboratory equipment so he brought it home and instructed his children in its use. In this way, Maria was taught to experiment at an early age.


Teenage

For some years, Maria was home-schooled. But her father recognized her talent for scientific thinking and learning. Therefore, despite economic troubles, she was admitted to a prestigious learning centre for girls. Maria graduated with a gold medal in 1883 aged sixteen.

She was unable to join any regular institution of higher education because she was a woman. Her father then suggested to join the "secret flying university" a Polish patriotic institution (often in conflict with the governing Russian Empire) which welcomed women students.

During this time, she fell in love with a young man (who'd later go on to become a prominent Polish mathematician), Kazimierz Żorawski, his name. The two discussed marriage, but Żorawski’s parents rejected Marie due to her family's poverty and Kazimierz was unable to oppose them.

Higher education

Maria returned home to her father in Warsaw. The loss of relationship with Żorawski was heartbreaking for her and Władysław was devastated seeing his daughter in pain. Three years later, in 1890, he was able to secure a more lucrative position again and arranged for Maria to reach Paris.

Maria and her father

Maria proceeded her studies of physics and chemistry in the University of Paris where she would be known as Marie. She focused so hard on her studies that she sometimes forgot to eat. In 1893, Marie Skłodowska was awarded a degree in physics at age 26.



In 1894, she began her research career with an investigation of the magnetic properties of various steels. That same year French physicist Pierre Curie entered her life; and it was their mutual interest in natural sciences that drew them together.


Marriage

Eventually they began to develop feelings for one another and Pierre proposed marriage. Marie returned to Warsaw and told her father that in Pierre, she had found a new love, a partner, and a scientific collaborator on whom she could depend. Władysław agreed.

But she was still living under the illusion that she would be able to work in her chosen field in Poland. Pierre declared that he was ready to move with her to Poland, even if it meant being reduced to teaching French.

Things hadn't changed though as she was denied again because of her gender. A letter from Pierre convinced her to return to Paris and work with him in his small laboratory. In 1895, they were married and for their honeymoon, took a bicycle tour around the French countryside.

The Curies also got going with their research work in a converted shed (formerly a medical school dissecting room) which was poorly ventilated and not even waterproof. But they were very dedicated scientists and hardly discouraged by such problems.

Radioactivity

In 1896, Henri Becquerel discovered that uranium salts spontaneously emitted a penetrating radiation that could be registered on a photographic plate. Marie was intrigued by this new phenomenon (she coined the term radioactivity) and decided to look into it.

She hypothesized that the radiation was not the outcome of some interaction of molecules but must come from the atom itself. She began studying two uranium minerals, pitchblende and torbernite, and discovered that both pitchblende and torbenite were far more active than uranium itself.

Marie concluded that the two minerals must contain small quantities of radioactive substances other than uranium. In 1898, the couple announced their discovery of Polonium and Radium, elements previously unknown, which were far more active than uranium.

Four years later in 1902, the husband and wife team was able to separate 0.1 gram of radium chloride from a ton of pitchblende, a remarkable achievement, for which the duo shared the Nobel Prize in physics with Henri Becquerel.

The award money allowed the Curies to hire their first laboratory assistant. However, the Curies still did not have a proper laboratory. Upon Pierre Curie's complaint, the University of Paris relented and agreed to create a new laboratory, but it would not be ready until 1906.



In 1906, walking across a street of Paris in heavy rain, Pierre was struck by a horse-drawn vehicle and fell under its wheels, causing his skull to fracture. Marie, by then a mother to two beautiful daughters, Irène and Ève, was traumatized by her husband's death.

She continued to work in the new laboratory hoping to reach greater heights in physics and chemistry as a tribute to her husband Pierre. In 1910, she isolated the pure radium metal; and also defined a new unit  of radioactivity called "curie" in the memory of her late husband.


Affair & death

In 1911, Marie was on the front pages of local tabloids as a "foreign home-wrecker" after having an affair with French physicist Paul Langevin, a married man who was estranged from his wife. The news was exploited by her academic opponents, one declaring her "a detestable idiot."

There's no denying that the affair was painful for Langevin’s family, particularly for his wife, Jeanne, but at the time when the news broke out, Marie was giving a lecture in Brussels. And when she returned to Paris, she found an angry crowd outside of her house and had to seek refuge, with her little daughters.

The Swedish Academy of Sciences honored her a second time despite the Langevin Scandal. She was awarded the Prize in Chemistry for isolating radium hence becoming the only person to win Nobel Prize in two different sciences.

A month after accepting her 1911 Nobel Prize, she was hospitalized with depression and a kidney ailment. During her time at the hospital, she received a letter from Einstein, essentially saying, "please ignore the haters." Marie returned to her laboratory after a gap of about 14 months.

From then onwards, it became very difficult to focus on the sciences and even more so during the World War I. Also perhaps because Marie could not forgive herself after the incident. The war ended, and she was invited to Warsaw in a ceremony, laying the foundations of the Radium Institute.

Curie visited Poland for the last time in early 1934 (before the second world war) where she died of aplastic anemia, a condition due to long exposure to radiation. Her final resting place was decided Paris Panthéon alongside her husband Pierre. In 1935, a life-size statue of Maria Skłodowska Curie was established in a Warsaw park facing the Radium Institute.



Personality

She used to wear the same dress to laboratory every day, "If you are going to be kind enough to give me one," she instructed regarding a proposed gift for her wedding, "please let it be practical and dark so that I can put it on afterwards to go to the laboratory."

She refrained from patenting the radium-isolation process, so that the scientific community could do their research unhindered. Scientific endeavors were more dear to her than monetary benefits. In fact, she even gave much of her Nobel Prize money to friends, family, students, and research associates.

The curies were not religious and Marie was agnostic by choice. Neither wanted a religious service for their marriage ceremony. She wore a dark blue outfit, instead of a bridal gown, which would be worn by her in the lab for years to come. One of the guests quipped, "Skłodowska is Pierre's biggest discovery."

Today, the radium is used to produce radon, a radioactive gas which is used to treat some types of cancer. At the time of their discovery, a new industry began developing, based on radium (as in self-luminous paints for watches), but the Curies did not patent their discovery and benefited little from this increasingly profitable business.

Marie had the strong conviction that her work would provide important benefits for the rest of humanity, "I am one of those who think that the world will draw more good than evil from new discoveries," her passion for science was aroused in her early years, and remained intact until her last breath.

In her final years, she advocated bravely for invoking a scientific approach in the people, "Nothing in life is to be feared, it is only to be understood. Now is the time to understand more, so that we may fear less," she would say.

10 Recommended Books For Physics Students

The following is a complete (all-you-need) list of books that every physics student has to have in their library at home. From popular science best-sellers, to comprehensive guides and textbooks, this has it all. Want to study physics? Then read these books!

A brief history of time

Hawking wrote the book for non-specialist readers with no prior knowledge of physics and astronomy. He clearly possessed a natural teacher's gifts: easy good-natured humour and ability to illustrate the complexities of the subject through well thought out analogies.

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The book has sold more than 10 million copies in 20 years, and was translated into more than 30 languages by 2001. You may like to know: what makes it everyone's favorite? There are many, many things, including:

• A concise introduction by renowned astronomer, Carl Sagan, who declares Hawking a worthy successor of Newton and Dirac
• A whole range of topics (from the big bang to black holes) makes it the single best book on astrophysics for the common reader
  
• Illustrations by award-winning artist, Ron Miller, add to the beauty and mystery of science
• Mix of history and philosophy of physics and narration by Stephen Hawking

All in all, the book is a masterpiece, suggested to anyone who's driven by their curiosity. It infuses our thinking and questioning with a spiritual aspect: was there a beginning of time? why there's something rather than nothing? is the universe infinite or does it have boundaries? and, is there a god required to create it?

Feynman lectures Vol.1

Nobel Prize winning physicist, Richard Feynman, has often been called "the great explainer", particularly because of this book, which is held in high regard, especially by teachers, and even by leading physicists of the current times.

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There are 52 chapters in the first Feynman book alone, and each topic has been presented with unwavering enthusiasm and insight. The book is based on a series of lectures delivered by Feynman (on the request of California Institute of Technology) to undergraduate students. Even professors attended the lectures!

The Feynman lectures on physics are beautiful books, which will teach you a considerable amount of the long-view of physics. They will also inspire you and have you feeling as though you really understand physics for the first time in your life. Mainly mechanics, radiation and heat is recommended for the start.

Mathematical Methods

What is physics without maths? Plain observation, to be honest! Therefore, it is absolutely necessary to get yourself familiar with mathematical methods in order for you to translate the physical reality into concrete concepts and language. There are hundreds of books available but none of them as good as this one:

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What makes it stand out from the crowd? As you can tell from the image, it is a thick textbook (1362 pages) of math, containing 31 chapters: from preliminary algebra, to beginner and advanced-level calculus, from complex numbers to quantum operators. In short, whatever's required to do physics and engineering, the book has it!



Quantum mechanics

This book written by renowned American physicist and professor Leonard Susskind is an excellent introduction to quantum mechanics from the ground level (pun intended). It contains in-depth physics as well as minimum mathematical tools required to tackle the most bizarre field of science.

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One may also consider the book by David Griffiths which is more mathematically inclined than Susskind's book. The book is full of illustrative examples and numerical exercises at the end of each chapter. For fun and non-serious reading, buy Graphic guide to Quantum mechanics.

For the love of physics

In this book, Professor Walter Lewin will introduce a mystery and then show how you can understand it with just a little bit of physics. 'The' Bill Gates himself has endorsed the book by saying, "The book captures Lewin's extraordinary intellect, passion for physics, and brilliance as a teacher."

According to Walter Lewin, "Teachers who make physics boring are criminals.. and if you hate physics, you have probably learned it from the wrong teacher." Because, he says, "Physics is naturally interesting!"

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For more than 40 years, Professor Lewin has honed his singular craft of making physics not only accessible but truly fun.This book has his stories, his research in physics, tips on teaching, and serves as an all-round motivation for students, to love and enjoy physics of everyday life.

When you finish reading the book, you will feel blessed, reminded of the tiny miracles of physics, happening all the time, around you. According to one review on Amazon, "If you like physics, this book's for you. If you hate physics, this book's for you. Lewin is phenomenal!"



Relativity

Published by Einstein himself with the aim of giving an exact insight into the theory of relativity to those readers who, from a general scientific and philosophical point of view, are interested in the theory, but who are not conversant with the mathematical toolkit of theoretical physics.

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Both special and general versions of the theory have been included in the book. Einstein has succeeded in putting across the fundamentals of his theory for undergraduate students before they can decide to go deep in the field.

Handbook of formulas

If you want to keep important notes, key terms, definitions and formulae of physics by your side, then this book is made for you. It is about 450 pages thick and recommended for revision purposes in all exams, especially for classes 11 and 12.

The chapters have been illustrated with well-designed diagrams and illustrations with examples. The book is a handy book, which can be used as ready reference. On the whole, the data is precise and presented in a form that can help students in the long run.

Cosmos

The word "cosmos" has ancient origin but popularized first by American astronomer Carl Sagan in the twentieth century. In this book, he has told the story of fifteen billion years of cosmic evolution, science and civilization, in the most comprehensible and exciting way.

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This book has 13 chapters on a range of topics: astronomy, physics, chemistry, biology, psychology and philosophy. In one sentence, "it is amalgamation of the sciences" in one book, a complete text that every mind passionate about learning must own.

In fact, the book also became an inspiration for the likes of Neil deGrasse Tyson, who went on to become an astrophysicist himself! He followed further in the footsteps of his hero and created a TV show of the same name, Cosmos: A Spacetime Odyssey.

Written some 38 years ago, the book single-handedly managed to draw the attention of people towards the wonders of science; for the first time in history, science no more seemed alien and became a thing of familiarity. Cosmos is relevant even today, for the data, the thought processes, the inferences remain all the same.

Halliday Resnick Walker

This well-known textbook is often called the bible for physics. It is recommended for high school students to prepare for competitive examinations like IIT-JEE. In 2002, the American Physical Society named it the most outstanding introductory physics text of the 20th century.

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The textbook covers all the fundamental topics in physics:

• Mechanics
• Waves
• Thermodynamics
• Electromagnetism
• Optics
• Special Relativity
• Quantum theory
• Nuclear physics
• Cosmology

It is as good as its Indian equivalent Concepts of Physics by H.C. Verma. The book by Professor Verma is divided over two parts but this book is 1300 pages, all-in-one, making it the first choice of many aspirants.

Autobiography of Feynman

Richard Feynman was an artist, a story-teller and an everyday joker whose life was a combination of his intelligence, curiosity and uncertainty. This book is his autobiography written with his friend Ralph Leighton.

According to one review, "It is a good funny read for everyone who loves physics and common sense. Easy and engaging language which takes you back in those days when Feynman stood tall among all giants of physics like Bohr, Bethe, Oppenheimer etc."

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Why is this book included in the list? Firstly, because it is entertainment coming from a Nobel Prize winning scientist! Of course when you're tired of struggling with maths and physics, you want to have some fun, and if reading happens to be your hobby, this book has numerous hilarious anecdotes from Feynman's personal life.

Second, this book also is motivational in nature. Feynman has continuously reminded his readers that even the idiotic, ordinary or average folk, can go on to achieve great things in life. He has then given valuable tips on how to learn and how to teach physics. So overall, this book is a good read for any physics student.

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.