Showing posts with label History. Show all posts
Showing posts with label History. Show all posts

10 Facts About Astrophysicist Subrahmanyan Chandrasekhar

Subrahmanyan Chandrasekhar astrophysics nobel prize science nasa

Astrophysicist Subrahmanyan Chandrasekhar [1910 - 1995] was a Nobel prize winning scientist from India who is best known for studying the evolution of stars. He accepted American citizenship in 1953 and taught at the University of Chicago for almost all his life.

Following are 10 amazing facts on physicist Subrahmanyan Chandrasekhar:

1. He found the Chandrasekhar limit, currently accepted as 1.4 solar masses, which is the maximum mass of a stable white dwarf star. If a star is more massive than this limit, it might end up as a black hole.

2. Chandrasekhar was tutored at home until the age of 12. In middle school, his father taught him mathematics and physics while his mother taught him Tamil and English.

3. Chandrasekhar studied at Presidency College in Chennai and the University of Cambridge. He was a long-time professor at the University of Chicago and editor of The astrophysical journal.

4. His paternal uncle was the Indian physicist and Nobel laureate C.V. Raman, who was the first Indian to win the coveted Nobel prize for discovery of Raman effect.

astrophysicist S Chandrasekhar won the Nobel Prize in 1983


5. Subrahmanyan Chandrasekhar himself won the Nobel prize for physics in 1983 for his mathematical treatment of stellar evolution.

6. Chandra X-ray observatory, launched in 1999, is a flagship space telescope of NASA which is named after him.

7. Chandrasekhar was in dispute with English astronomer Arthur Eddington over the final stages of a star's life. Eddington, a renowned physicist, openly mocked and criticized Chandrasekhar limit in 1935.
Chandrasekhar continued to state that he admired Eddington and considered him a friend.

8. Chandra worked closely with his students and expressed pride in the fact that over a 50-year period (from roughly 1930 to 1980), the average age of his co-author collaborators had remained the same, at around 30.

9. Two of the students who took his course at University of Chicago, Tsung-Dao Lee and Chen-Ning Yang, won the Nobel prize before he could get one for himself. Chandrasekhar supervised 45 PhD students in his teaching career.

10. After his death, his wife Lalitha made a gift of his Nobel Prize money to the University of Chicago towards the establishment of the Subrahmanyan Chandrasekhar Memorial Fellowship.

Bonus fact - Chandrasekhar was offered double salary at Princeton University in 1946 but the University of Chicago president matched the salary to keep Chandrasekhar in Chicago.

5 Predictions of Nikola Tesla That Came True (And 5 That Didn't)

5 predictions of nikola tesla that were right, 5 wrong predictions of nikola tesla

Nikola Tesla was a genius Serbian American inventor who laid the foundations of alternate current power system. Tesla was an advocate of modern technology and made many convincing predictions about the future. Some of Tesla's predictions were proven correct in the 21st century and some have gone wrong, as you shall see in this post.

1. (Right) Alternating current


Nikola Tesla pioneered the generation, transmission and use of alternating current electricity. Tesla believed that one day in the future the entire world would use his power system over direct current.

Thomas Edison famously tried to show with experiment that alternating current was deadly. However, Tesla overcame that fear mongering by showing that AC was safe, inexpensive and usable over large distances.

2. (Wrong) Interplanetary energy exchange

One can see that Tesla and his ideas were on another level when he said that he would be able to complete interplanetary communication. In 1931, Tesla proposed a way in the future that would allow planets to transmit energy, from one planet to another, in large amounts of horsepower - regardless of distance.

3. (Right) Smartphone

In 1908, Tesla said - An inexpensive instrument, not bigger than a watch, will enable one to call up, from one's desk, and talk to any telephone subscriber on the globe. Any picture, character, drawing, or print can be transferred from one to another place.

5 right predictions of nikola tesla, 5 wrong predictions of nikola tesla


4. (Wrong) Unlimited free energy

Tesla envisioned a future in which humans are able to harness the energy of ionosphere and distribute it wirelessly to anyone anywhere on the planet. This concept, while inspiring, has not been realized because of practical reasons.

5. (Right) Thought images, MRI

Tesla: I expect to photograph thoughts. In 1893, while engaged in certain investigations, I became convinced that a definite image formed in thought must produce a corresponding image on the retina, which might be read by a suitable apparatus.

The closest machine able to do as Tesla suggested is MRI scan. An fMRI scan can tell you something about what a person is thinking. Tesla predicted - "Our minds would then, indeed, be like open books."

6. (Wrong) Wireless electricity

One notable incorrect prediction of Nikola Tesla is transmission of wireless electricity through the air. There would be no need for wires in the future for long distance transfer using his Wardenclyffe tower. This idea of Tesla was impractical on many levels and was not realized on large scale.

5 right predictions of nikola tesla, 5 wrong predictions of nikola tesla


7. (Right) Wi-fi


While wireless electricity did not succeed, wireless transfer of files - documents, photos, music, video worked. His prediction of the internet came true in the 1980s and wireless file transfer in the 1990s.

8. (Wrong) Anti gravity tech


Tesla predicted an anti-gravity technology which would allow levitation in day to day life. Despite ongoing research in this field, anti gravity remains impractical and still quite far from reality.

9. (Right) Robotics and automation


Tesla predicted that robots will replace humans in many fields. He predicted driverless cars. He predicted robots would do menial labor like lifting and loading. Today, not only this, but automation via artificial intelligence is putting human creativity at risk, as they create art and music.

10. (Wrong) Weather control

While modern science has explored temporary weather modification techniques like cloud seeding, a complete control of weather and climate as Tesla had envisioned has not come to fruition.

Paul Dirac versus Richard Feynman

dirac verus feynman physics


Feynman and Dirac, two great physicists who made invaluable contribution to quantum mechanics and Nobel prize winners, were poles apart.

While Richard Feynman idolized Paul Dirac, they disagreed on many things. One remembers Dirac as an extremely shy person, who hesitated to speak. Feynman, on the contrary, was a chatty man whose anecdotes spread contagious laughter.

Dirac won the Nobel prize for correctly predicting the existence of anti-matter. Three decades later, Feynman won the coveted prize for his work with elementary particles.

Both physicists had a very distinct view of science. Dirac was inclined towards mathematics and considered beauty in one's equations to be important. While Feynman preferred the equation to stand the test of experiment.

Feynman said - Physics is not mathematics. Mathematics is not physics. One helps the other.

Dirac was of the view - It is more important to have beauty in one's equations than to have them fit experiment.

You can say that in this regard Feynman and Dirac were rivals as they say "Raibaru" in Japanese. They did not seem to agree on this one thing.

Yet, as a young man Feynman idolized Dirac. He said - 

Dirac made a breakthrough, a new method of doing physics. He had the courage to simply guess at the form of an equation, and to try to interpret it afterwards.

This equation is now called Dirac equation. It is a beautiful, small equation that predicts counterpart of matter, anti-matter. In 1932, Paul Dirac was recognized by Nobel prize in physics for his work.

Later on, Feynman's views changed.

Being a mathematical physicist, Dirac was of the view that if an equation has beauty, then one must be working correctly, on the right path. Feynman disagreed that beauty is paramount, but he still remained a Dirac fanboy.

Feynman's evolved thought was

No matter how beautiful an equation is, no matter who made the equation or how genius he was, if it disagrees with experiment, it is wrong!

In 1962, the two great minds Feynman and Dirac met at a science conference.

dirac feynman rivalry physics


Feynman a chatty fellow talked at length while a meek old man Dirac listened quietly. In the end, Dirac blurted out a question - I have an equation. Do you have one too?

Earlier in 1948, Feynman had invented a diagram to pictorially represent the interaction of subatomic particles. For this simplification work, Feynman won the Nobel prize in 1965. It is then interesting to note that both scientists won the Nobel prize in physics for proposing a simple solution.

One key takeaway from this story is that it takes courage to challenge your idol. Feynman admired Dirac all his life, but it was not wrong for him to disagree with his hero once in a while. Isn't that how science progresses? When great minds collide?

Feynman's Letter To Deceased Wife Breaks Stereotype

richard feynman letter to dead wife physics science

It is said that men cannot express themselves well enough. Building upon this notion, often times TV shows tend to portray that male scientists [or as they say geeks] cannot convey feelings of love and usually get awkward in social situations.

However, there was one outspoken physicist by the name Richard Feynman who not only broke this stereotype but went beyond. Feynman was a great teacher, artist and lover.

Feynman's love for his wife knew no bounds. He wrote about it in a book titled What do you care what other people think? [a phrase his wife Arline taught him]. The book was later on adapted into a movie starring Matthew Broderick as Richard Feynman and Patricia Arquette as Arline Greenbaum in 1996.

Arline was struck by tuberculosis and was bed ridden for the latter part of her short lived life. Feynman used to commute from work to the hospital every day, a place which became their home in the last few years. He brought her presents and flowers and promised to stay by her side until her last breath. Feynman stood by his word.

When Arline passed away, every other thing reminded Feynman of the time he had spent with her. A cute dress by the window of a shop brought tears to his eyes, as Feynman imagined how his departed wife Arline would look in it.

Following is a letter that Feynman wrote 16 months after Arline had passed away. He just could not get over her for a really long time as this letter shows...

October 17, 1946

D’Arline,

I adore you, sweetheart.

I know how much you like to hear that — but I don’t only write it because you like it — I write it because it makes me warm all over inside to write it to you.

It is such a terribly long time since I last wrote to you — almost two years but I know you’ll excuse me because you understand how I am, stubborn and realistic; and I thought there was no sense to writing.

But now I know my darling wife that it is right to do what I have delayed in doing, and that I have done so much in the past. I want to tell you I love you. I want to love you. I always will love you.

I find it hard to understand in my mind what it means to love you after you are dead — but I still want to comfort and take care of you — and I want you to love me and care for me. I want to have problems to discuss with you — I want to do little projects with you. I never thought until just now that we can do that. What should we do. We started to learn to make clothes together — or learn Chinese — or getting a movie projector. Can’t I do something now? No. I am alone without you and you were the “idea-woman” and general instigator of all our wild adventures.

 


When you were sick you worried because you could not give me something that you wanted to and thought I needed. You needn’t have worried. Just as I told you then there was no real need because I loved you in so many ways so much. And now it is clearly even more true — you can give me nothing now yet I love you so that you stand in my way of loving anyone else — but I want you to stand there. You, dead, are so much better than anyone else alive.

I know you will assure me that I am foolish and that you want me to have full happiness and don’t want to be in my way. I’ll bet you are surprised that I don’t even have a girlfriend (except you, sweetheart) after two years. But you can’t help it, darling, nor can I — I don’t understand it, for I have met many girls and very nice ones and I don’t want to remain alone — but in two or three meetings they all seem ashes. You only are left to me. You are real.

My darling wife, I do adore you.

I love my wife. My wife is dead.

Rich.

PS Please excuse my not mailing this — but I don’t know your new address.

 

5 Quotes By Isaac Newton To Inspire Students

isaac newton quotes physics

Isaac Newton was an English physicist who is credited for the invention of calculus. He is best known for the discovery of the laws of motion and the universal law of gravitation.

Newton laid the foundations for modern physics. Following are 5 quotes by Sir Isaac Newton that everyone should know:

1. If I have seen further it is by standing on the shoulders of Giants.

2. To explain all nature is too difficult a task for any one man or even for any one age...

3. I do not know what I may appear to the world, but to myself I seem to have been only like a boy playing on the sea-shore, whilst the great ocean of truth lay all undiscovered before me.

4. God created everything by number, weight and measure. We must be righteous & do to all men as we would they should do to us.

5. I can calculate the motions of the heavenly bodies, but not the madness of the people.

10 Less Known Facts About Physicist S.N. Bose

sn bose satyendra nath bose facts physics

Satyendra Nath Bose was an Indian physicist who is best known for his contributions to statistical mechanics. Together with Albert Einstein, Bose is famous for the theory of Bosons and Bose Einstein condensate.

Following are 10 unbelievable facts about S.N. Bose which you may not know:

1. Bose was well versed in several languages including English, Bengali, Hindi, French, German and Sanskrit. He is remembered by his colleagues as a polyglot.

2. Since Bose had not done a doctorate, Einstein’s recommendation helped him become a professor. He served as a professor in Dhaka and then in Calcutta until 1956.

3. Seven Nobel Prizes have been awarded for research related to the concepts of the Bosons and the Bose-Einstein Condensate but Bose himself never won the most coveted prize.


4. Bose was good friends with several famous physicists including Indian physicist Meghnad Saha, English physicist Paul Dirac and Swiss mathematician Marcel Grossmann.

5. It was said that when Niels Bohr got stuck with a problem during his lecture in Calcutta, S.N. Bose instantly resolved it.

6. In 1919, Bose and Saha translated Einstein's book on the theory of relativity which was in German and published it in English. It was the first English translation of Einstein's groundbreaking work of 1915.

7. Paul Dirac coined the term Boson in the honor of S.N. Bose.

8. Bose wrote a letter to Einstein about a collaboration. Einstein immediately recognized Bose's genius and extended Bose's idea to the atoms that led to the existence of Bose Einstein condensate - the fifth state of matter.

9. Satyendra Nath Bose was devastated by the division of Bengal on the basis of religion in 1905. He was also depressed by the division of India and Pakistan and felt it to be a wound in the heart of his beloved nation.

10. Bose was also gifted when it came to music. He played an Indian stringed instrument called Esraj which sounded like a violin.

Why Edwin Hubble Never Won A Nobel Prize?

edwin hubble nobel prize astronomy

Edwin Hubble [1889-1953] was the first person to discover that the universe was expanding. He also found that Milky Way is just one of many galaxies in the universe. Thus, Hubble emerged as a pivotal figure in the field of astronomy in the 20th century.

Despite being a pioneer of his field, and doing work that revolutionized modern physics, why did American astronomer Edwin Hubble never win a Nobel Prize?

Early life


Hubble was more famous for his athletic prowess than scientific achievements in teenage life. He was gifted at baseball and football in high school. Not only that, Hubble led the University of Chicago's basketball team to their first major title in 1907.

Hubble's academic journey began with a bachelor of science degree, which he finished in 1910. As a college student, he served as a lab assistant to future Nobel laureate Robert Millikan, the discoverer of value of elementary charge.

Astronomy work


Hubble earned a law degree at Oxford University as a Rhodes scholar, demonstrating his diverse intellectual capabilities. He also studied Spanish for a while. However, his passion for science and astronomy prevailed over other interests.

In the 1920s, Hubble utilized a powerful 100-inch telescope at Mount Wilson Observatory in California to observe distant galaxies.

All the galaxies looked reddish in color. Like a siren whose sound gets lower and lower as it moves away. In terms of light, red is a color of low frequency. Hubble concluded that the galaxies were going away from us, so their wavelengths were stretched.

Ours was not a static universe like Albert Einstein had imagined, but it was an expanding universe, as Hubble had observed. This gave birth to the concept of the Big Bang theory.

Nobel prize


Edwin Hubble's notable contributions to the field of astronomy did not win him a Nobel Prize, and there are several reasons for this.

Firstly, at the time of Hubble's discovery in 1929, the Nobel Prize in Physics did not recognize work done in astronomy. Hubble spent the latter part of his career to have astronomy considered an area of physics.

Secondly, Hubble's work was truly groundbreaking, it changed our view of the cosmos, and the Nobel Committee may not have fully grasped the long-term implications immediately.

Thirdly, Hubble's work was more observational in nature and not supported by theory and experiment. It was dependent on Hubble's own interpretation of redshift data.

Legacy


Hubble's work was a key piece of evidence in supporting the idea of an expanding universe. Hubble has a crater on the moon and an asteroid named after him.

edwin hubble astronomy nobel prize

Hubble's legacy was further solidified when in 1990 Hubble Space Telescope was launched, capturing stunning images of distant nebulae, galaxies and other amazing cosmic phenomena.

5 Amazing Quotes By Max Planck On Science

max planck quotes science physics

Max Planck [1858-1947] was a German physicist who discovered energy quanta and laid the foundations of quantum mechanics in 1900. This won him the Nobel Prize in physics in 1918.

Best known for Planck's constant, denoted by h, Planck was a devout man who believed that his work with subatomic particles revealed to him the deepest secret of the universe.

According to Max Planck, the very greatest scientists of all times - such as Kepler, Newton, Leibniz - were permeated by a most profound religious attitude.

Early life


Max Planck was the sixth child in a family of intellectuals. His teacher Hermann Muller recognized the young talent and taught Planck astronomy and mathematics early on, aged 12.

Planck was gifted when it came to music. He played piano, organ and cello, and composed songs of his own. However, instead of music he chose physics for a career.

max planck science

Planck's professor at University of Munich advised him not to study physics because in that field "almost everything is already discovered." Planck replied he just wanted to know more about the universe.

However, by discovering quantum theory Max Planck opened a whole new field of quantum mechanics which in turn gave rise to modern technology.

Quotes by Planck


1. Experiments are the only means of knowledge at our disposal. The rest is poetry, imagination.

2. Science cannot solve the ultimate mystery of nature. That is because, in the last analysis, we ourselves are part of nature and therefore part of the mystery that we are trying to solve.

3. We have no right to assume that any physical laws exist, or if they have existed up to now, that they will continue to exist in a similar manner in the future.

4. What we perceive as matter is merely the manifestation of a force that causes the subatomic particles to oscillate and holds them together in the tiniest solar system of the universe.

5. Over the entrance to the gates of the temple of science are written the words: Ye must have faith. It is a quality which the scientist cannot dispense with.

Why Astronomer Carl Sagan Was An Agnostic?

carl sagan astronomy science and religion quotes

Carl Sagan was a renowned American astronomer who is best known for his show, Cosmos: a personal voyage. Sagan, an expert in the field of exobiology, persuaded NASA for Mars missions and to search for exoplanets with signs of life.

When asked about his religious belief, Carl Sagan did not assertively pick a side. He did not know for sure if there was a God. Carl was also uncomfortable about being labeled an atheist. That is why, Sagan claimed to be agnostic—to not hold any belief about God's existence.


In an interview, Carl Sagan described his unique idea of God, as a set of physical laws that govern the universe, which is the same as what Albert Einstein also believed.

However, Carl Sagan was an open critic of blind belief. At one point, Sagan also believed that religion or God was unnecessary in modern day society.

"Where did God come from?" Carl Sagan asks believers. "If we say that God always existed, why not save a step, and conclude that the Universe always existed?" Carl argues.


Carl Sagan adds that science has enlarged our picture of the universe. In some respects, science has far surpassed religion in delivering awe. "The Universe is much bigger than our prophets said, grander, more subtle, more elegant", Sagan wrote in the book Pale blue dot.

Carl Sagan also criticized the idea of perfection - that God is perfect. He wrote in the book Contact - "Why didn't God start the universe out in the first place so it would come out the way he wants? Why's he constantly repairing and complaining? God is not good at design or execution".

Despite writing extensively not in favor of religion, Carl Sagan never described himself as an atheist, as boldly as contemporaries like Richard Feynman did. Carl Sagan was an agnostic because according to him: "Extraordinary claims require extraordinary evidence."

richard feynman atheist carl sagan agnostic
Richard Feynman was an atheist

"To be certain of the existence of God and to be certain of the nonexistence of God seem to me to be the confident extremes in a subject so riddled with doubt and uncertainty as to inspire very little confidence indeed". Carl Sagan adds.

On the other hand, Feynman had said: I call myself an atheist. Agnostic for me would be trying to weasel out and sound a little nicer than I am about this.

Who Was Eugene Wigner?

eugene wigner nobel prize nuclear physics

Eugene Wigner was a Hungarian American physicist who made important contributions to the physics of elementary particles. He was a Nobel laureate who was nicknamed "a silent genius" by his colleagues.

Advice for students


Wigner said: In science, it is not speed that is the most important. It is the dedication, the commitment, the interest and the will to know something and to understand it — these are the things that come first.

Early education


Eugene Wigner (1902-1995) was born to a middle class family and home schooled till the age of 9. During this time period, he developed an interest in mathematical problems.

Wigner started off by studying chemical engineering at the Technical University of Berlin. There he got the opportunity to attend seminars by leading German scientists: Max Planck, Werner Heisenberg and Albert Einstein. As a result, Wigner decided to pursue a career in physics.

Interesting fact


Eugene Wigner and Paul Dirac had become close friends in America. In 1934, at Princeton, Wigner introduced his sister Manci Wigner to Dirac, with whom she married.

Known for


Wigner was the first to identify several characteristics of the strong nuclear force, such as the fact that the force between two nucleons is the same, regardless of whether they are protons or neutrons. The strong force is charge independent.

Notable awards


Eugene Wigner won the Nobel Prize in physics in 1963. Earlier, he had won the Enrico Fermi award in 1958 for his work with nuclear reactors to convert Uranium into Plutonium.

5 Quotes By CV Raman, India's Nobel Laureate

cv raman nobel prize indian scientist physics

CV Raman was an Indian physicist who won the Nobel Prize in 1930. His discovery of the "Raman Effect" has extensive use in chemistry to provide a structural fingerprint by which strange molecules can be identified. Raman used to say "Ask the right questions, and nature will open the doors to her secrets."

Raman was born into an orthodox South Indian Brahmin family but his interests in the sciences kept him away from religious or spiritual activities. Eventually he described himself as an agnostic. Following are some amazing quotes by the first Indian Nobel laureate in science, CV Raman:

1. There is no Heaven, no Swarga, no Hell, no rebirth, no reincarnation and no immortality. The only thing that is true is that a man is born, he lives and he dies. Therefore, he should live his life properly. (1934)

Many started referring to Raman as an atheist, which he denied.

2. If there is a God we must look for him in the Universe. If he is not there, he is not worth looking for. I am being looked upon in various quarters as an atheist, but I am not. The growing discoveries in the science of astronomy and physics seem to be further and further revelations of God. (1945)

3. In a conversation with Mahatma Gandhi, Raman said "Mahatma ji, religions cannot unite. Science offers the best opportunity for a complete fellowship. All men of Science are brothers."

Raman was also active politically. He was famous for being an advocate of women's rights.

4. I have a feeling that if the women of India take to science and interest themselves in the progress and advance of science as well, they will achieve what even men have failed to do. Women have one quality--the quality of devotion. It is one of the most important passports to success in science.

5. As a political activist, Raman said: It seems to me that the real danger before our country is the crushing down of individual freedom and initiative by the steamroller of government authority. Democracy without freedom for the individual is a sham and a delusion. (1954 interview)

You can judge that CV Raman was not only a pioneering scientist but also a great thinker whose thoughts were progressive and way ahead of the time. Raman was the first Indian to win Nobel Prize in science who contributed immensely to the idea of agnosticism.

5 Amazing Inventions By Physicists We Use Every Day

5 science inventions we use in daily life, examples of physics in every day life

Did you know that one of the first video games was invented by a physicist? Why do you have to put your bags through a machine when you enter airport? In this post, we will look at five simple or somewhat complicated inventions by physicists that are used in daily life.

Although, from Wi-Fi to smart TV - physics is everywhere around us in the form of modern technology. The following are inventions we rarely talk about, or are thankful for, despite making use of them on regular basis.

1. Lever


Archimedes said, “Give me a firm place to stand and a lever and I can move the Earth." That was never tested but a lever is put to use in many forms today: Stapler, a pair of scissors and seesaw. There are different classes of levers:

a) Class I lever is when fulcrum is between load and effort. Example: Seesaw.
b) Class II lever is when load is between fulcrum and effort. Example: Door.
c) Class III lever is when effort is between fulcrum and load. Example: Stapler.



2. Video games

Physics has had an important impact in the early development of video games. In 1958, physicist William Higinbotham created what is thought to be the first video game. It was called Tennis For Two, a very simple game that shaped the history of computer games.

3. Electric generator

Physicist Michael Faraday invented the first electric motor in 1821. Shortly after, Faraday invented the electric generator, based on electromagnetic induction discovered by him. This is used to generate electrical power - which in turn is used to run electrical appliances.

When Faraday first presented induction, he was asked by some politician or reporter: What use is it in the practical world? To this Faraday replied, What use is a newborn baby?

4. Battery


While Faraday invented a way to generate electrical power by fluctuating magnetic fields, another physicist Alessandro Volta had invented a way to store electrical power in 1800. In honor of Volta, the SI unit of electric potential is called Volt. Today, almost all the toys that children play with use batteries.

5. X-ray

Some say that Nikola Tesla discovered x-rays by accident. Others credit Wilhelm Roentgen for inventing a way to generate x-rays in 1895. Whatever the case may be, did you know that x-rays are not only used in healthcare but also in the security industry? Every time your luggage passes through a security machine, an officer can see what is inside your bags.

How Rutherford Became Father of Nuclear Physics

how rutherford became father of nuclear physics

"It is JUST AS surprising - as if a gunner fired a shell at a single sheet of paper and for some reason or other, the projectile BOUNCED BACK."

This is how New Zealand physicist Ernest Rutherford described the result of alpha particle scattering experiment - conducted by his students Geiger and Marsden.

Introduction


Geiger and Marsden aimed high speed alpha particles at a very thin gold foil - it was only 1000 atoms thick. Around the gold foil was a zinc sulphide screen which glowed every time alpha particles would hit it.

If Thomson's plum pudding model of atom were correct, the fast moving and relatively heavier alpha particles would have passed straight thought the target, since electric field generated by evenly distributed charge is very minimal.

rutherford model of atom vs thomson model



But the experiment revealed that a few alpha particles were deflected by small angles, while 1 in 20,000 particles got deviated by angle greater than 90 degrees.

rutherford model of atom, gold foil alpha experiment



Rutherford set out to explain these unusual findings by creating a new model of atom, because Thomson's model had failed.

Early life and career 


Ernest Rutherford [1871-1937] was a multi-talented student who did phenomenally well in mathematics, catching everyone's attention at his school as a consequence.

He won the scholarship to study at Canterbury College, University of New Zealand, where he participated not only in the lab but also in the debating society.

Rutherford was the head boy in college and played the rugged sport of rugby. He completed three degrees in this college - ba, ma and bsc.

Thereafter, he travelled to England in order to study under the guidance of J. J. Thomson at the Cambridge University. Rutherford worked with cathode ray tubes under Thomson's mentorship. 

In 1899, he heard about Henri Becquerel's discovery of radioactivity and became interested in exploring alpha and beta decay. Rutherford was among the first to prove that alpha particles were Helium nuclei.

"All science is either physics or stamp collecting." Rutherford used to say, but ironically he won the Nobel Prize in chemistry in 1908 for his pioneering work with on the chemistry of radioactive substances.

Discovery of Nucleus 


As discussed earlier, alpha particle scattering experiment was conducted by Rutherford, Geiger and Marsden in the year 1909, by passing alpha particles through a thin gold foil.

Rutherford argued that since most of the particles passed straight through the gold foil, the atom must be made up of mostly empty space - not a positive soup as Thomson had thought.

In fact, the atom is about 100,000 times the diameter of the nucleus. It is like putting a grain of sand in the middle of a soccer ground!

Positive charge must be localized, Rutherford argued, in a very small point at the center of atom, which explained bouncing back in a small fraction of alpha particles, since positive positive repel.

Negative charges in the atom must be located somewhere on the outskirts ... which explained smaller deflections.

rutherford father of nuclear physics


Summing up


By creating a new improved model, Rutherford became the father of nuclear physics, as he initiated a whole new branch of physics. Scientists decided to probe further into the nucleus and many subatomic particles were discovered as a result.

Upon the discovery of atomic nucleus, Rutherford said: "I have broken the machine and touched the GHOST OF MATTER." But he regretted not being able to explain something deeper - "when we found the nucleus, we found the basis of everything, the greatest secret of all - except of life."
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