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 * __Einstein's Theory of Relativity__**

Albert Einstein founded this theory of relativity in 1905. His theory deals mainly with objects and particles that are moving at the speed of light.


 * Exactly what is Einstein's Theory of Relativity?**
 * Classic relativity involves transformation between a moving object and an observer in another inertial frame of reference. It was originally defined by Galileo Galilel, was later improved by Newton (Jones).
 * Relativity describes moving particles close to the speed of light and gives correct motion laws for any particle.
 * There are two separate aspects to the theory: general relativity and special relativity. Special relativity was defined first and was later thought to be a special case of the general relativity theory.
 * The theory of special relativity is derived from Einstein's two basic postulates of special relativity: (1) the speed of light is the same for all observers, no matter what their relative speeds. (2) The laws of physics observed by a hypothetical observer traveling with a relativistic particle must be the same as those observed by an observer who is stationary in the laboratory ("Theory: Special Relativity).
 * Einstein's first postulate is the significant idea that led him to formulate his theory of special relativity. A quantity //c// (speed of light) can be defined from this idea. The speed of light, or //c//, is an elementary constant of nature (Jones).
 * While Einstein's first postulate was basically common knowledge, his second postulate was the **new** idea. It was the result of massless photons moving at velocity c in a vacuum, as stated in Einstein's paper about the photoelectric effect. The paper introduced the photon theory of light. It squashed the previous idea that light traveled through a universal substance known as ether ("Theory: Special Relativity").
 * Einstein demonstrated how the definitions of momentum and energy need to be altered. He also showed how length, time, and other quantities must change from one oberserver to another in order to obtain consistent results for physical quantities. Einstein demonstrated all of this with his theory for special relativity ("Theory: Special Relativity").
 * Physicists have conducted a number of experiments in order to prove the predictions that Einstein's theory makes are correct. Each experiment has proved that yes, the predictions are correct!
 * The simplest form of the relativity equation is: (curvature of space-time) = (mass-energy density) x 8 pi G / //c//. This equation gives a direct, constant proportion and is the relationship between the curvature of space-time and mass-energy density (Jones).
 * How is the theory applied to the world and universe?**
 * The term "theory of relativity" was applied to the ideas of the speed of light and mass-energy relationship by Max Planck in 1908 because general relativity did not exist yet.
 * The special theory of relativity predicts that time does not move at a stationary rate; it is dependent on their stationary counterparts. However, this becomes significant only at elevated speeds that close in on the speed of light ("General Relativity"). [[image:http://www.dreamstime.com/theory-of-relativity-thumb3733903.jpg width="210" height="215" align="center" caption="Time dilation (www.dreamspace.com)"]]
 * When gravitation is included, the equations of relativity predict that the gravity (the curvature of spacetime) stretches and shrink distances, as well as appear to decelerate or "dilate" the flow of time ("General Relativity").
 * Time dilation is usually very insignificant, however that can change when spacetime is bent by massive objects such as blackholes. An observer that is far from a blackhole would never see an astronaunt falling into the hole: to the observer, the time of the astronaut would seem to stop ("General Relativity").
 * The theory of general relativity suggests that matter causes space to curve ("General Relativity").
 * The curve that more massive objects, such as Earth, make is stronger than the curve that lighter objects, such as the moon, make. The curve produced by Earth (gravity) is what keeps us on it. However, the curve that the moon makes is strong enough to affect the tides on Earth (Jones).




 * Many physicists dismissed the theory at first because they thought that it was too "theoretical and counterintuitive"; overtime through thorough experiments, the theory proved to be true
 * Are there people willing to dismiss Einstein's theory?**
 * Many controversies surround the theory; some accuse Einstein of being a plagiarist while others think the theory interferes with quantum mechanics.
 * Some people accuse Einstein of being a plagiarist because a majority of the work that makes up the relativity theory had already been established, along with the concepts of time dilation and simultaniety for moving bodies. They were established by Lorentz and Poincare (Jones).
 * Einstein received the most credit for his work. Einstein mounted the previous work onto a theoretical framework that made them more than mathematical cons to save a theory that was slowly fading (Jones).
 * General relativity also fails to correspond with quantum mechanics. Theoretical physicists are dedicated to integrate the two concepts: "One predicts macroscopic phenomena across space and one which predicts microscopic phenomena, often within spaces smaller than an atom" (Jones).
 * Attention is also called to Einstein's idea of **spacetime**. The idea of spacetime was originally described by Hans von Baeyer, who described spacetime as an invisible stream that flows infinitely and curves when it faces objects in its path. It carries everything in the universe and is one of the basic postulates of the Theory of General Relativity ("General Relativity"). People are skeptical about whether it really does exist.


 * Many people have pointed out that if spacetime does truly exist as a physical entity, it would be a universal frame of reference. This fact excites anti-relativists but others view it as an attempt to disprove Einstein's theory by bringing a century-dead idea back to life.
 * It is unlikely that the theory will be damaged or discredited in any way, unless a major event occurs that completely contradicts Einstein's theory.

Works Cited "Albert Einstein - Spacetime Relativity Theory." __New Science Theory.__ 2009. 27 Jan 2009. <[|http://new-science-theory.com]>

Boen, Brooke. "Gravity Probe B: The Relativity Mission." NASA. 23 Nov 2007. NASA. 27 Jan 2009.  pages/gpb/gpb 012.html> Jones, Andrew Zimmerman. “Einstein’s Theory of Relativity.” __About.com: Physics__. 2009. 22 Jan. 2009  "General Relativity." __NCSA.__ 7 Nov 1995. The Board of Trustees of the University of Illinois. 27 Jan 2009. <[]> "Theory of Relativity." __Dreamstime.__ 27 Jan 2009. < http://www.dreamstime.com/theory-of-relativity-image3733903 >. “Theory: Special Relativity.” __Virtual Visitor Center at SLAC__. 31 Oct. 2008. SLAC National Accelerator Laboratory. 23 Jan. 2009  Throne, Robin. "Distance Learning in Einstein's Fouth Dimension." __Third Education Group Review/Essays.__ 27 Jan 2009. 