Albert Einstein
Albert Einstein, born in Ulm , Germany in 1879 ,He is universally regarded as one of the greatest physicists of all time . His astonishing scientific career began with the publication of three path breaking paper’s in 1905 . In the first paper . He introduced the notion of light quanta ( now called photon’s ) and use it to explain the features of photoelectric effect that the classical wave theory of radiation could not account for . In the second paper , he developed a theory of Brownian motion that was confirmed experimentally . A few years later and provided a convincing evidence of the atomic picture of matter . The third paper gave birth to the special theory of relativity that made Einstein a legend in his own life time in the next decade he explored the consequence of his new theory in which included among other things the mass energy equivalence enshrined in his famous equation is equal to MC square. He also created the general version of relativity which is the modern theory of gravitation. some of Einstein’s most significant letter contribution are the notion of stimulated emission introduced in an alternative derivation of Planck’s black body radiation law, static model of the universe which started modern cosmology quantum statistics of a gas of massive bosons and a critical analysis of the foundation of quantum mechanics. the year 2005 was declared as international year of physics in recognition of Einstein’s monumental contribution to physics. In 1905 describing revolutionary scientific ideas that have since influenced all of modern physics
Galileo Galilei
Galileo Galilei born in Pisa Italy in 1564 was a key figure in the scientific revolution in Europe about four centuries ago . Galileo proposed the concept of acceleration from experiments on motion of bodies is on incline plane or falling freely . he contradicted the aristotelian notion that a force was required to keep a body in motion and that heaviers body’s fall faster than lighter body under gravity . He thus arrived at the law of inertia that was the starting point of the subsequent epochal work of Isaac Newton . Galileo’s discoveries in astronomy were equally revolutionary. In 1609, he designed his own telescope and use it to make a number of startling observation: mountain and depression on the surface of the moon 🌒 darks spot on the sun â›… the moon’s of the Jupiter’s and the phases of Venus . He concluded that the milky way derived its luminosity because of a large number of stars not visible to the naked eye . In his masterpiece of scientific reason: dialogue on the two chief world systems. Galileo advocated the heliocentric theory of the solar system proposed by Copernicus, which eventually got universal acceptance. With Galileo name a turning point in the very method of scientific inquiry. science was no longer merely observation of nature and inference from them. Science meant devising and doing experiments to verify the refute theories.science meant measurement of quantities and a search of mathematical relation between them. Not undeservally , many regards Galileo as the father of modern science
Isaac Newton
Isaac Newton was born in woolsthorp, England in 1642 , the year Galileo died .is extra ordinary mathematical ability and mechanical aptitude remained hidden from others in his school life. In 1662 , he went to Cambridge for undergraduate studies, A plague epidemic in 1665 forced the university town to close and Newton had to return to his mother’s farm. There in two years of solitude, His dormant creativity blossomed in a deluge of fundamental discoveries in mathematics and physics : binomial theorem of negative and fractional exponents, the beginning of calculus , inverse Square law of gravitation, the spectrum of white light and so on, returning to Cambridge , he pursued his investigation in optics and devised a reflecting telescope ,In 1684 encourage by his friend Edmund Hailey , Newton embarked on writing what was to be one of the greatest scientific work ever published: The Principia Mathematica . In it , he enunciated the three laws of motion and the universal law of gravitation, which explain all the three Kepler’s law of planetary motion. The book was packed with the host of path breaking achievements: basics principles of fluids mechanics , mathematics of wave motion , calculation of Masses of the earth ,the sun and other planets , explanation of the process of equinoxes, theory’s of tides etc .in 1704 , Newton brought out another master optics that summarised his work on light and colour.the scientific Revolution triggered by Copernicus and steered vigorously ahead by Kepler and Galileo was brought to a grand kompally by Newton. Newtonian mechanics unified terrestrial and celestial phenomena . the same mathematical equation governed the fall of an apple to the ground and the motion of the moon around the earth. The age of reasons had dawned.
Satendranath Bose ( A great Indian scientists )
Satendranath Bose born in Calcutta ( Kolkata ) in 1894 , He is among the great Indian physicist who made a fundamental contribution to the advance of science in the twentieth century. An outstanding student throughout , boss started his career in 1916 as a lecturer in physics in Kolkata university 5 year later he join Daccka university. Here in 1924 , in brilliant flash of insight , boss give any derivation of Planck’s law, treating radiation as a gas of photons and employing new stastistical method of counting of photon States.He wrote a short paper on the subject and send it to Einstein who immediately recognise it great significance. Translated it in German and forwarded it for publication . Einstein done applied the same method to a gas of molecules. The key new conceptual ingredient in Bose’s work was that the particle were regarded as indistinguishable ,a radical departure from the assumption that underlies the classical Maxwell Boltzmann statistics . it was soon released that the new boss Einstein statics was applicable to particle with intergers Spins, and a new quantum statics was needed for particle with half intergas spin stattisfying Pauli’s exclusion principle, particles with intergas spin are now known as bosons in honour of Bose
an important consequence of Bose Einstein statistics is that a gas of molecules below a certain temperature will undergo a phase transition to a state where large fraction of atom populate the same lowest energy state.some 70 years were to pass before the pioneering ideas of boss, develop further by Einstein, where dramatically confirm in the observation of a new state of matter in a dilute gas of ultra cold alkali atom – the Bose Einstein condenstate
Sir C.V Raman
Chandrasekhar venkataraman was born on 7 November 1888 in thiruvanaikkaval . He finished his schooling by the age of 11. 1 graduate from presidency college, Madras . after finishing his education he joined financial service of the Indian government.while in Kolkata started working on his area of interest at Indian association for cultivation of science founded by doctor Mahendra lal Sirkar during his evening hour . Is area of interest included vibration , variety of musical instrument , ultrasonic , diffraction and so on. In 1917 he was offered professor ship at Kolkata university. In 1924 he was elected fellow of the royal society of London and received Nobel prize in physics , in 1930 for his discovery , now known as Raman Effect
the Raman effect deals with the scattering of light by molecule of a medium when they are excited to vibrational energy level this work open totalling new avenues for research for year to come . He spent his letter year at Bangalore first at Indian institute of science and then he spent his letter year at Raman research Institute . His work has inspired generation of young student .
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