The Landscape Again and again.... |
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(September 20, 2010) Leonard Susskind gives a lecture on the string theory and particle physics. He is a world renown theoretical physicist and uses graphs to help demonstrate the theories he is presenting.
String theory (with its close relative, M-theory) is the basis for the most ambitious theories of the physical world. It has profoundly influenced our understanding of gravity, cosmology, and particle physics. In this course we will develop the basic theoretical and mathematical ideas, including the string-theoretic origin of gravity, the theory of extra dimensions of space, the connection between strings and black holes, the "landscape" of string theory, and the holographic principle.
This course was originally presented in Stanford's Continuing Studies program.
Stanford University:
http://www.stanford.edu/
Stanford Continuing Studies Program:
http://csp.stanford.edu/
Stanford University Channel on YouTube:
http://www.youtube.com/stanford
Playlist
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Quarks, gluons and anti-quarks are the constituents of protons, neutrons and (by definition) other hadrons. It is a fascinating aspect of the physics of our world that when one of these particles is kicked out of the hadron that contains it, flying out with high motion-energy, it is never observed macroscopically. Instead, a high-energy quark (or gluon or anti-quark) is transformed into a spray of hadrons [particles made from quarks, antiquarks and gluons]. This spray is called a “jet.” [Note this statement applies to the five lighter flavors of quark, and not the top quark, which decays to a W particle and a bottom quark before a jet can form.] See: Jets: The Manifestation of Quarks and Gluons
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See Also:
- Quark Soup: Applied Superstring Theory
- How Particles Came to be?
- The First Few Microseconds, by Michael Riordan and Willaim A. Zajc
For the past five years, hundreds of scientists have been using a powerful new atom smasher at Brookhaven National Laboratory on Long Island to mimic conditions that existed at the birth of the universe. Called the Relativistic Heavy Ion Collider (RHIC, pronounced "rick"), it clashes two opposing beams of gold nuclei traveling at nearly the speed of light. The resulting collisions between pairs of these atomic nuclei generate exceedingly hot, dense bursts of matter and energy to simulate what happened during the first few microseconds of the big bang. These brief "mini bangs" give physicists a ringside seat on some of the earliest moments of creation.
During those early moments, matter was an ultrahot, superdense brew of particles called quarks and gluons rushing hither and thither and crashing willy-nilly into one another. A sprinkling of electrons, photons and other light elementary particles seasoned the soup. This mixture had a temperature in the trillions of degrees, more than 100,000 times hotter than the sun's core.