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Young's double-slit experiment applied to the interference of single electrons

Neither Newton nor Young was quite right about the nature of light. Though it is not simply made of particles, neither can it be described purely as a wave. In the first five years of the 20th century, Max Planck and then Albert Einstein showed, respectively, that light is emitted and absorbed in packets -- called photons. But other experiments continued to verify that light is also wavelike.

It took quantum theory, developed over the next few decades, to reconcile how both ideas could be true: photons and other subatomic particles -- electrons, protons, and so forth -- exhibit two complementary qualities; they are, as one physicist put it, ''wavicles.''

To explain the idea, to others and themselves, physicists often used a thought experiment, in which Young's double-slit demonstration is repeated with a beam of electrons instead of light. Obeying the laws of quantum mechanics, the stream of particles would split in two, and the smaller streams would interfere with each other, leaving the same kind of light- and dark-striped pattern as was cast by light. Particles would act like waves.

According to an accompanying article in Physics Today, by the magazine's editor, Peter Rodgers, it wasn't until 1961 that someone (Claus Jönsson of Tübingen) carried out the experiment in the real world.

By that time no one was really surprised by the outcome, and the report, like most, was absorbed anonymously into science. (Ranking: 1,)

Whether they are blasting apart subatomic particles in accelerators, sequencing the genome or analyzing the wobble of a distant star, the experiments that grab the world's attention often cost millions of dollars to execute and produce torrents of data to be processed over months by supercomputers. Some research groups have grown to the size of small companies.

But ultimately science comes down to the individual mind grappling with something mysterious. When Robert P. Crease, a member of the philosophy department at the State University of New York at Stony Brook and the historian at Brookhaven National Laboratory, recently asked physicists to nominate the most beautiful experiment of all time, the 10 winners were largely solo performances, involving at most a few assistants. Most of the experiments -- which are listed in this month's Physics World -- took place on tabletops and none required more computational power than that of a slide rule or calculator.

What they have in common is that they epitomize the elusive quality scientists call beauty. This is beauty in the classical sense: the logical simplicity of the apparatus, like the logical simplicity of the analysis, seems as inevitable and pure as the lines of a Greek monument. Confusion and ambiguity are momentarily swept aside, and something new about nature becomes clear.

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Follow this link to watch the experiment performed by Robert Millikan in 1909.
http://www.youtube.com/watch?v=XMfYHag7Liw

If you want to know more about "Diffused Axonal Injury", then visit this link:
http://www.youtube.com/watch?v=2RgzIjeKbXo

The idea about the 11 most amazing experiments on 11.11.11 was a fascinating one indeed. while researching i came across so many different kinds of experiment and actually helped me gain insight on how these scientific experiments have so much of importance in our lives. I researched on the experiment by Ernest Rutherford-The gold Foil experiment. simple, yet rather intriguing indeed. it fascinated me to find out that just one beam of light passing through a gold foil can hold so much importance in the entire scientific journey. truly amazing!

I completely agree with you Arwa ben. I too had come across this experiment and all I want to say is that it's beauty lies in its simplicity and the fact that the experiment solves one of the greatest mysteries of time-The structure of an atom.

Arwa said:

The idea about the 11 most amazing experiments on 11.11.11 was a fascinating one indeed. while researching i came across so many different kinds of experiment and actually helped me gain insight on how these scientific experiments have so much of importance in our lives. I researched on the experiment by Ernest Rutherford-The gold Foil experiment. simple, yet rather intriguing indeed. it fascinated me to find out that just one beam of light passing through a gold foil can hold so much importance in the entire scientific journey. truly amazing!

well the best experiment i came across was the clone of an animal done by John Gurdon,of a frog tadpole from an egg cell using a nucleus from an intestine cell, in 1962.also that his experiment proved that a cell's genetic potential do not diminish as the cell became specialized, disproving the conclusion of Robert Briggs and Thomas King following their failures to clone from differentiated cells in their 1952 landmark tadpole experiment. Gurdon's results electrified the scientific community.

if you want to know more about about the gold foil experiment by rutherford then visit this link:
http://www.youtube.com/watch?v=5pZj0u_XMbc

What happens when the King orders you to assay if his crown is pure gold?
You can't melt the crown to find its density, as it would make him furious.
Then what do you do?
This is what happened to Archimedes. Archimedes gave a lot of thought on this, however he didn't seem to find a solution.
Finally, when he was having a bath, he noticed that the water in the tub rose as he got in. Thats when he realised that he could use this effect to procure the density of the crown.
And today because of him we know the concept of determining the volume of an irrelgular object by dropping it in the water and calculating the amount of water it displaces....

To read more about this famous mathematician, please follow this link:
http://en.m.wikipedia.org/wiki/Archimedes

To watch a video about this fascinating discovery please visit:
http://www.youtube.com/watch?v=ZUYkBeAW5hc

I researched about the fascinating experiment performed by Robert Millikan determining the size of the charge on an electron.
What Millikan did was to put a charge on a tiny drop of oil, and measure how strong an applied electric field had to be in order to stop the oil drop from falling. He first sprayed some oil in a chamber and calculated their mass. Next, Millikan applied a charge to the falling drops this helped the electrons to attach with the oil drops. By attaching a battery he was able to apply an electric voltage. The electric field produced in the bottom chamber by this voltage would act on the charged oil drops. He then used a formula including the mass, acceleration and the electric force applied to calculate the charge on an electron.

I ALSO RELLY ENJOYED THE PROJECT AND THE RESEARCH WAS THE BEST PART I CAME TO MANY NEW AND BEAUTIFUL EXPERIMENTS THE EXPERIMENT I CHOSE FOR THE 11:11:11 PROJECT WAS ON Millikan Oil Drop Experiment IT DETERMINED HOW HE COULD CALCULATE THE SPEED OF AN OIL DROP AS IT FELL

Galileo's experiments with rolling balls down inclined planes

Galileo continued to refine his ideas about objects in motion. He took a board 12 cubits long and half a cubit wide (20 feet by 10 inches) and cut a groove, as straight and smooth as possible, down the center. He inclined the plane and rolled brass balls down it, timing their descent with a water clock -- a large vessel that emptied through a thin tube into a glass. After each run he would weigh the water that had flowed out -- his measurement of elapsed time -- and compare it with the distance the ball had traveled.

Aristotle would have predicted that the velocity of a rolling ball was constant: double its time in transit and you would double the distance it traversed. Galileo was able to show that the distance is actually proportional to the square of the time: Double it and the ball would go four times as far. The reason is that it is being constantly accelerated by gravity

The Briggs–Rauscher oscillating chemical reaction is one of a small number of known oscillating chemical reactions. It is especially well suited for demonstration purposes because of its visually striking color changes: the freshly prepared colorless solution slowly turns an amber color, suddenly changing to a very dark blue. This slowly fades to colorless and the process repeats, about ten times in the most popular formulation, before ending as a dark blue liquid smelling strongly of iodine. The chemicals used in the reaction are hydrogen peroxide, potassium iodate, malonic acid, and manganese (ii) sulphate monohydrate, concentrated sulphuric acid and soluble starch. This oscillating reaction was developed by Thomas S. Briggs and Warren C. Rauscher of Galileo High School in San Francisco. In their reaction the evolution oxygen and carbon dioxide gases and the concentrations of iodine and iodide ions oscillate. Iodine is produced rapidly when the concentration of iodide ions is low. .As the concentration of iodine in the solution increases, the amber color of the solution intensifies. The production of I increases as the concentration of I2 increases. And these ions react with iodine molecules and starch to form a blue-black complex containing the pentaiodide ion (I5).

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