These are stories about Science: the myths of our time. The myth has an important role in the society : these stories have made Science a part of the collective consciousness.Let's be honest:the true appreciation of scientific ideas requires hard work; there is no royal way to Science. But these stories,that can be appeciated by anyone,may help to make Science an integral part of our culture.
Archimedes Bath:Eureka
Archimedes was a near relation of Hieron the King of Syracuse. He said the famous sentence:GIVE ME A PLACE TO STAND AND I WILL MOVE THE EARTH meaning that with a proper lever he could move any load.He demonstrated this by moving alone a big ship. But the most famous story about Archimedes is how he was able to demonstrate to Hieron that a goldsmith had replaced some of the gold in a commissioned crown with cheaper silver. He put into a bowl filled with water to the brim a weight of silver and then a weight of gold equal to the crown. He measured how much water was spilled in the two cases, then he put the crown and found that the water collected in this case was between the two previous measures.
This solution occurred when he stepped into his bath and caused it to overflow.So delighted was Archimedes with his solution that he leaped from his bath and ran through the streets of Syracuse crying "Eureka!
Big Bang and Black Hole
The Big Bang is ,of course, the starting of the Universe from a single point in space around 15 billions of years ago(but at the beginning space and time don't themselves exist). Black holes are created when a star with enough matter ends its nuclear fuel and collapses unto itself becoming a single point in space. In some way the forming of a black hole is like a Big Bang in reverse. The two terms have made two rather abstruse scientific concepts immensely popular.
Chandrasekhar,his limit and what's
happens to old stars
What happens when a star has burnt all its supply of hydrogen? As Chandrasekhar, a physicist winner of the 1983 Nobel prize discovered, it all depends on the size.With a size below the Chandrasekhar limit the star will collapse becoming a white dwarf. Just imagine the Sun becoming small like Earth and also getting colder and colder:not very interesting. With a mass bigger than 1.44 that of the Sun(this is the Chandrasekhar limit) something incredible happens. The star will literally blow up its gaseous envelope with a supernova explosion and the core of the star will collapse to the center becoming something so compressed that a few kilometers of radius contain all the star material. This is the neutron star that usually is spinning very fast and can be dectected from Earth as a pulsar:a kind of cosmic clock. But the really fantastic thing happens with sizes even bigger: in this case the supernova remains will collapse in a Black Hole:all the mass confined in a single point!
Einstein : e=mc2
E=mc2 is the unique mathematical expression of a physical law entered in the collective consciousness.In a explosive way, when the first atomic bomb exploded in 1945 transforming few grams of matter in a blast that destroyed a city.Einstein wasn't part of the project Manhattan that built the bomb although a letter written by him to the Usa president perhaps had some influence on the start of the project. Instead the famous formula was the result of the so called special relativity theory created by Einstein at the beginning of the century. Then Einstein wasn't thinking about atomic bombs but only about the curious fact that the light speed (the c in the formula is the light's speed) was the same no matter how fast you were moving.
Fermi: The Italian Navigator has Landed in the New World
Building an atomic bomb is extremely simple if you have enough Uranium of the "right type". You put it toghether until at some "critical quantity" it explodes. This is the "chain reaction". Enrico Fermi did know well the theory, but until someone tried it , this was only a theory. Altough the atomic bomb was built in Los Alamos and other centers with huge expenses of resources, its feasibility was demonstrated by a simple experiment carried out by Fermi and a group of other scientists in a squash court of the University of Chicago. They assembled toghether enough uranium that could start the chain reaction.In order not to be blown away by a sudden explosion, but to control it, he used a lot of graphite and some cadmium rods that could be used to have a fast control by inserting them among the uranium. Fermi was in fact able to start the chain reaction and to control it (not obvious).The famous sentence was a code to inform about the success of the experiment .
Galileo : Eppur si muove
"And yet it (Earth) does move" . Almost certainly Galileo never said this famous sentence. Galileo Galilei published his Dialogue on the two chief world systems in Florence in 1632 with the Church approvation. But shortly after the publication he was summoned by the Holy Office to Rome. He was condemned and forced to a abjure of his theory. During these events Galileo was over sixty years old and in bad health conditions. He made no opposition at all to the Curch tribunal.
Moderation Team
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