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100 People Who Changed History and the World "The only true wisdom is in knowing you know nothing." ― Socrates Edited By Manjunath.R #16/1, 8th Main Road, Shivanagar, Rajajinagar, Bangalore560010, Karnataka, India *Corresponding Author Email: [email protected] *Website: http://www.myw3schools.com/ This book takes readers back and forth through achievements of 100 world's most inspirational and influential people (from brainy biologists and clever chemists to magnificent mathematicians and phenomenal physicists) who have shaped our society and how we see the world around us. Contents 100 Most Influential Scientists Who Shaped World History 1 100 most influential people in the world 176 100 Most Influential Scientists Who Shaped World History [1] Sir Isaac Newton Birth: Dec. 25, 1642 [Jan. 4, 1643, New Style], Woolsthorpe, Lincolnshire, England Death: March 20 [March 31], 1727, London Known for: the Newtonian Revolution Sir Isaac Newton was an English physicist and mathematician and was the culminating figure of the Scientific Revolution of the 17th century. In optics, his discovery of the composition of white light integrated the phenomena of colours into the science of light and laid the foundation for modern physical optics. In mechanics, his three laws of motion, the basic principles of modern physics, resulted in the formulation of the law of universal gravitation. In mathematics, he was the original discoverer of the infinitesimal calculus. Newton’s Philosophiae Naturalis Principia Mathematica (Mathematical Principles of Natural Philosophy, 1687) was one of the most important single works in the history of modern science. [2] Albert Einstein Birth: March 14, 1879, Ulm, Wurttemberg, Germany Death: April 18, 1955, Princeton, N.J., U.S. Known for: Twentieth-Century Science Albert Einstein was a German-born physicist who developed the special and general theories of relativity and won the Nobel Prize for Physics in 1921 for his explanation of the photoelectric effect. Einstein is generally considered the most influential physicist of the 20th century. [3] Niels Bohr 1 Birth: Oct. 7, 1885, Copenhagen, Denmark Death: Nov. 18, 1962, Copenhagen Known for: the Atom Niels Henrik David Bohr was a Danish physicist who is generally regarded as one of the foremost physicists of the 20th century. He was the first to apply the quantum concept, which restricts the energy of a system to certain discrete values, to the problem of atomic and molecular structure. For that work he received the Nobel Prize for Physics in 1922. His manifold roles in the origins and development of quantum physics may be his most-important contribution, but through his long career his involvements were substantially broader, both inside and outside the world of physics. [4] Charles Darwin Birth: Feb. 12, 1809, Shrewsbury, Shropshire, England Death: April 19, 1882, Downe, Kent Known for: Evolution Charles Robert Darwin was an English naturalist whose scientific theory of evolution by natural selection became the foundation of modern evolutionary studies. An affable country gentleman, Darwin at first shocked religious Victorian society by suggesting that animals and humans shared a common ancestry. However, his nonreligious biology appealed to the rising class of professional scientists, and by the time of his death evolutionary imagery had spread through all of science, literature, and politics. Darwin, himself an agnostic, was accorded the ultimate British accolade of burial in Westminster Abbey, London. [5] Louis Pasteur Birth: Dec. 27, 1822, Dole, France Death: Sept. 28, 1895, Saint-Cloud, near Paris Known for: the Germ Theory of Disease 2 Louis Pasteur was a French chemist and microbiologist who was one of the most important founders of medical microbiology. Pasteur’s contributions to science, technology, and medicine are nearly without precedent. He pioneered the study of molecular asymmetry; discovered that microorganisms cause fermentation and disease; originated the process of pasteurization; saved the beer, wine, and silk industries in France; and developed vaccines against anthrax and rabies. [6] Sigmund Freud Birth: May 6, 1856, Freiberg, Moravia, Austrian Empire [now Přibor, Czech Republic] Death: Sept. 23, 1939, London, England Known for: Psychology of the Unconscious Sigmund Freud was an Austrian neurologist and the founder of psychoanalysis, a clinical method for treating psychopathology through dialogue between a patient and a psychoanalyst. [7] Galileo Galilei Birth: Feb. 15, 1564, Pisa [Italy] Death: Jan. 8, 1642, Arcetri, near Florence Known for: the New Science Galileo was an Italian natural philosopher, astronomer, and mathematician who made fundamental contributions to the sciences of motion, astronomy, and strength of materials and to the development of the scientific method. His formulation of (circular) inertia, the law of falling bodies, and parabolic trajectories marked the beginning of a fundamental change in the study of motion. His insistence that the book of nature was written in the language of mathematics changed natural philosophy from a verbal, qualitative account to a mathematical one in which experimentation became a recognized method for discovering the facts of nature. Finally, his discoveries with the telescope revolutionized astronomy and paved the way for the acceptance of the Copernican heliocentric system, but his advocacy of that system eventually resulted in an Inquisition process against him. 3 "If I have seen further it is by standing on the shoulders of Giants." ― Isaac Newton Newton's Three Laws of Motion: Every object in a state of rest will remain in that state of rest unless an external force acts on it. Force = mass × acceleration. For every action there is an equal and opposite reaction. Newton's law of universal gravitation: GMm FG = R2 where FG denote the gravitational force acting between two objects, M and m the masses of the objects, r the distance between the centers of their masses, and G the gravitational constant. "Logic will get you from A to Z; imagination will get you everywhere." ― Albert Einstein Einstein's mass-energy relation Energy = mass × (speed of light) 2 Einstein's special relativity equations: rest mass Relativistic mass = (velocity)2 √1− (speed of light) 2 (velocity)2 Contracted Length = original length × √1 − (speed of light)2 stationary time Dilated time = (velocity)2 √1− (speed of light) 2 Einstein's Photoelectric Equation: Minimum energy needed Maximum kinetic energy Energy of photon = + to remove an electron of the emitted electron Einstein's General Theory of Relativity: Strain ∝ stress Space-time curvature ∝ mass-energy stress Curvature from stuff Curvature of space-time Mass-energy stress in space-time + itself = "Those who are not shocked when they first come across quantum theory cannot possibly have understood it." ― Niels Bohr In 1911, fresh from completion of his PhD, the young Danish physicist Niels Bohr left Denmark on a foreign scholarship headed for the Cavendish Laboratory in Cambridge to work under J. J. Thomson on the structure of atomic systems. At the time, Bohr began to put forth the idea that since light could no long be treated as continuously propagating waves, but instead as discrete energy packets (as articulated by Max Planck and Albert Einstein), why should the classical Newtonian mechanics on which Thomson's model was based hold true? It seemed to Bohr that the atomic model should be modified in a similar way. If electromagnetic energy is quantized, i.e. restricted to take on only integer values of hυ, where υ is the frequency of light, then it seemed reasonable that the mechanical energy associated with the energy of atomic electrons is also quantized. However, Bohr's still somewhat vague ideas were not well received by Thomson, and Bohr decided to move from Cambridge after his first year to a place where his concepts about quantization of electronic motion in atoms would meet less opposition. He chose the University of Manchester, where the chair of physics was held by Ernest Rutherford. While in Manchester, Bohr learned about the nuclear model of the atom proposed by Rutherford. To overcome the difficulty associated with the classical collapse of the electron into the nucleus, Bohr proposed that the orbiting electron could only exist in certain special states of motion - called stationary states, in which no electromagnetic radiation was emitted. In these states, the angular momentum of the electron L takes on integer values of Planck's constant divided by 2π, h denoted by ℏ = (pronounced h-bar). In these stationary states, the electron angular momentum 2π can take on values ħ, 2ħ, 3ħ... but never non-integer values. This is known as quantization of angular momentum, and was one of Bohr's key hypotheses. He imagined the atom as consisting h h of electron waves of wavelength λ = = endlessly circling atomic nuclei. mv p In his picture, only orbits with circumferences corresponding to an integral multiple of electron nℏ wavelengths could survive without destructive interference (i.e., r = could survive without mv destructive interference). For circular orbits, the position vector of the electron r is always perpendicular to its linear momentum p. The angular momentum L has magnitude mvr in this case. Thus Bohr's postulate of quantized angular momentum is equivalent to mvr = nℏ where n is a positive integer called principal quantum number. It tells us what energy level the electron occupies. "You cannot teach a man anything, you can only help him find it within himself." ― Galileo Kinematic Equations: Final velocity = Initial velocity + (acceleration × time) 1 Displacement = (Initial velocity × time) + [acceleration × (time)2] 2 (Final velocity)2 = (Initial velocity)2 + 2 (acceleration × Displacement) "In our acquisition of knowledge of the Universe, that which renovates the quest is nothing more nor less than complete innocence. In this state of complete innocence we receive everything from the moment of our birth. Although so often the object of our contempt and private fears, it is always in us. It alone can unite humility with boldness to allow us to penetrate to the heart of things or allow things to enter us and taken possession of us.