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String theory

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Gauge theory from McGraw-Hill Concise Encyclopedia of Science and Technology. SYMMETRY from Routledge Philosophy Companions: The Routledge Companion to Philosophy of Science. Unit 57. Written for students in the USC Self-paced Astronomy courses NOTE: This Unit assumes you have studied Unit 56. The Learning Objectives and references are in the Self-Paced Study Guide Essay on the General Theory of Relativity by John L. A. Consider yourself in an elevator. Fig. 57-1: Locally being at rest on the Earth's surface is equivalent to being in a uniformly accelerated spaceship. Consider the opposite case. Fig. 57-2: Locally freely falling towards the Earth is equivalent to being at rest with respect to the distant stars far from any gravitating body. We see that gravity is different than other forces. "For sufficiently small regions, the special theory of relativity is correct!!

" Einstein used these ideas to conclude that the laws of physics should be independent of the coordinate system used. B. Consider our elevator example again, only this time cut small windows in the elevator so light can pass through the elevator. Consider the following question. Now becomes, in general, C. The Theory of Strings: A Detailed Introduction: Sunil Mukhi. Return to Sunil Mukhi's Home Page The Theory of Strings: A Detailed Introduction Sunil Mukhi Introduction. String theory, also known by names such as "superstring theory" and sometimes "M-theory", is an idea that has been around for a rather long time, over two decades. It is, at one and the same time, a logical continuation of established theoretical notions dating back over half a century, and a radical new paradigm in fundamental physics. Perhaps it is this paradoxical nature of String Theory that explains why it attracts so much attention today.

To appreciate what string theory aims to achieve and how it attempts to fulfill these aims, it is necessary to recollect the present formulation of the physics of elementary particles and fields. Elementary Particles and Fields. Consider the familiar force of electromagnetism. The classical field theory of electromagnetism breaks down at very short distances, or in the presence of very strong fields. Table 1: The Fundamental Forces and Carriers. Www.frankwilczek.com/Wilczek_Easy_Pieces/298_QCD_Made_Simple.pdf. Document Page: What string theory tells us about the universe. Document Page: Physics 2005: the Super-Strange World of Superstrings and Extra Dimensions.

What is String Theory ? We live in a wonderfully complex universe, and we are curious about it by nature. Time and again we have wondered--- why are we here? Where did we and the world come from? What is the world made of? It is our privilege to live in a time when enormous progress has been made towards finding some of the answers. String theory is our most recent attempt to answer the last (and part of the second) question. So, what is the world made of? Our current knowledge about the subatomic composition of the universe is summarized in what is known as the Standard Model of particle physics.

There are four fundamental forces in the universe: gravity, electromagnetism, and the weak and strong nuclear forces. The behavior of all of these particles and forces is described with impeccable precision by the Standard Model, with one notable exception: gravity. In the last few decades, string theory has emerged as the most promising candidate for a microscopic theory of gravity. The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory: Brian Greene: 9780393338102: Amazon.com. The Complete Idiot’s Guide to String Theory. How is the universe put together? What came before the big bang?

What would happen to you if, god forbid, you fell into a black hole? Is time travel possible? What is space? For answers to the deepest questions in science, physicists have sought to merge their current theories into a unified theory. The Complete Idiot’s Guide to String Theory captures the present state of that search and brings you up to speed on the leading contender for a unified theory, known as string theory, as well as the major alternatives. This site offers errata, links, and other goodies. The book is designed for anyone who feels intimidated by physics. Pdf/physics/9403001v1.pdf. The Official String Theory Web Site. String theory for non-physicists - String Theory Wiki. See also Colloquia books The Elegant Universe: Superstrings, Hidden Dimensions, and the Quest for the Ultimate Theory by Brian Greene (1999) One of the most popular books on the subject.

The first part gives a basic overview of strings as well as background material on relativity and quantum mechanics. The second part describes more advanced ideas concerning details of the extra dimensions required by string theory. The Fabric of the Cosmos: Space, Time and the Texture of the Cosmos by Brian Greene (2004) The Complete Idiot's Guide to String Theory by George Musser (2008) Gives a basic explanation of string theory, loop quantum gravity, and several other theories, including their application to black holes and cosmology.

Hyperspace: A Scientific Odyssey Through Parallel Universes, Time Warps and the Tenth Dimension by Michio Kaku (Oxford University Press, 1994) This work focuses on the extra dimensions of string theory, including much background material. videos websites Superstrings! Pdf/physics/0311047v2.pdf.