The Men Behind

Nicolaus Copernicus
(February 19, 1473 – May 24, 1543) was the first astronomer to formulate a scientifically based heliocentric cosmology that displaced the Earth from the center of the universe. His epochal book, De revolutionibus orbium coelestium (On the Revolutions of the Celestial Spheres), is often regarded as the starting point of modern astronomy and the defining epiphany that began the Scientific Revolution. Copernicus was a mathematician, astronomer, physician, classical scholar, translator, Catholic cleric, jurist, governor, military leader, diplomat and economist.

Galileo Galilei

(15 February 1564, Pisa, Italy– 8 January 1642, Arcetri, Tuscany Italy ). He was a physicist, mathematician, astronomer, and a philosopher who made several discoveries, which were relevant for the Scientific Revolution. His achievements include improvements to the telescope and consequent astronomical observations, and support for Copernicanism. The motion of uniformly accelerated objects, taught in nearly all high school and introductory college physics courses, was studied by Galileo as the subject of kinematics. His contributions to observational astronomy include the discovery of the four largest satellites of Jupiter, named the Galilean moons in his honour, and the observation and analysis of sunspots. Galilei observed the Milky Way and found it to be a pack of stars, so densely that they appeared to be clouds from the Earth. Galileo also worked in applied science and technology, improving compass design.

Isaac Newton

(4 January 1643 – 31 March 1727 ) was an English physicist, mathematician, astronomer, natural philosopher, alchemist and theologian. His Philosophiæ Naturalis Principia Mathematica, published in 1687, is said to be the greatest single work in the history of science. In this work, Newton described universal gravitation and the three laws of motion, laying the groundwork for classical mechanics, which dominated the scientific view of the physical universe for the next three centuries and is the basis for modern engineering. Newton showed that the motions of objects on Earth and of celestial bodies are governed by the same set of natural laws by demonstrating the consistency between Kepler's laws of planetary motion and his theory of gravitation, thus removing the last doubts about heliocentrism and advancing the scientific revolution.

Albert Einstein

(March 14, 1879 at Ulm, in Württemberg, Germany– April 18, 1955)Einstein postulated that the correct interpretation of the special theory of relativity must also furnish a theory of gravitation and in 1916 he published his paper on the general theory of relativity. During this time he also contributed to the problems of the theory of radiation and statistical mechanics. Einstein's most important works include Special Theory of Relativity (1905), Relativity (English translations, 1920 and 1950), General Theory of Relativity (1916), Investigations on Theory of Brownian Movement (1926), and The Evolution of Physics (1938).

Copernicus, Galiei, Newton, Einstein. Retrieved from: http://en.wikipedia.org/wiki/

Christian Andreas Doppler

(1803 – 1853) Christian Doppler studied mathematics and astronomy in Czechoslovakia and Austria. He explained that the perceived change of frequency in light and sound waves was due to the relative motion of the source and the observer. His ideas helped pave the way for the idea that the universe is expanding, and made it possible to follow weather patterns by tracking electromagnetic radio waves. During his days as professor in Praga he published more than 50 articles in the areas of mathematics, phisics and astronomy.

The Doppler Shift was discovered by Christian Doppler when he noticed that sound travels in waves much like waves on the surface of the ocean. Doppler also noticed that when the source of the sound is moving, the pitch of the sound is different, depending on whether the source is moving toward or away from the observer.
Doppler Shift also works with light. When a light source is moving toward you, the light becomes more blue (called a blue shift). When a light source is moving away from you, the light becomes redder (called a red shift). And the faster something is moving, the farther the light is shifted. But the Doppler shift for light is very subtle and cannot be detected with the naked eye. Scientists use a device called a spectroscope to measure Doppler Shift and determine how fast stars and galaxies are moving.

http://www.astro.ucla.edu/~wright/doppler.htm
http://es.wikipedia.org/wiki/Christian_Andreas_Doppler

Edwin Hubble

(1889 – 1953) He was an American Astronomer. Hubble did some of the most important discoveries of the astronomy. Among them, we could find:
He determined the existence of several other galaxies, such as our Milky Way, by taking many photographs of Cepheid variables through 100 inch reflecting Hooker telescope, proving they were outside our galaxy
Hubble had also devised a classification system for the various galaxies he observed, sorting them by content, distance, shape, and brightness
He also discovered that the degree of redshift observed in light coming from a galaxy increased in proportion to the distance of that galaxy from the Milky Way. This became known as Hubble’s Law, and would help establish that the universe is expanding.
If universe is expanding outwards, it must have been coming from a central point, and that something must have caused that expansion to begin with. Thus, Hubble’s discoveries lead to the formulation of the Big Bang theory.

http://antwrp.gsfc.nasa.gov/diamond_jubilee/1996/sandage_hubble.html

George Gamow

(1904 – 1968) He was a Russian-American nuclear physicist and author. Some of his various scientific contributions were:
In 1928 he formulated a theory of radioactive decay and worked on the application of nuclear physics to problems of stellar evolution.
He was one of the first proponents of the “Big Bang” theory, and also one of its more valuable defenders
He was one of the first scientists who thought that the present levels of hydrogen and helium could be explained by the reactions ocurred during the Big Bang.
Gamow predicted that the afterglow of “Big Bang” radiation would have cooled down after billions of years, filling the universe with a radiation five degrees above the absolute zero (0 ºK = -273 ºC)
He developed equations for the mass and radius of a primordial galaxy (wich contains about one hundred billion stars)

http://personal.ifae.es/redondo/physics/biog/Gamow.pdf


Stephen Hawking

(1942… Present) He is a British theoretical physicist. He is also the Lucasian Professor of Mathematics at the University of Cambridge. He is known for his contributions to the fields of theoretical cosmology and quantum gravity.
Hawking combined the fields of Quantum Theory and General Relativity through his research. This combination of the two fields happened after he was able to show that when the General Theory of Relativity is utilized, this implies that both time and space would have a defined starting and ending point. The beginning would occur during the big bang and the end would be inside of the black holes.
Hawking theorized that black holes were not entirely black but in fact emitted certain types of radiation. Over time, the black holes could evaporate and ultimately disappear from existence.
Hawking also contributed to the idea of imaginary time. This sort of time is somewhat related to the idea of imaginary numbers (multiples of the square root of -1). In this realm of thought and existence, he has theorized that the universe would have no boundaries.
Hawking has also had an interest in the classification of gravitational waves.
Hawking has theorized that the arrow of time can only point in one direction which is forward.
Two more postulates that Hawking has formulated include wormholes and baby universes. He theorizes that only subatomic particles can travel through wormholes to alternate universes, if they in fact exist. Baby universes are another modification of the Big Bang Theory in that after the explosion many different universes were created like bubbles. Also, each bubble has the ability to create another baby universe.
Both Hawking and Kip Thorne have theorized that a singularity exists in the interior of a black hole.
In 2004 Hawking discovered that he was wrong about his hypotheses in wich he thought that a black hole destroys everything that falls into it. He did solve the enigma of the information in black holes: he claimed that he could now prove that this information wasn’t lost.

http://www.bbc.co.uk/sn/tvradio/programmes/horizon/hawking_prog_summary.shtml
http://www.usd.edu/phys/courses/phys300/gallery/clark/hawking.html