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Albert Einstein, who published his special theory of relativity in 1905, and his general theory of relativity in 1915, is often thought of as the most influential thinkers of the 20th century--and possible modern history (Arora). His theories, which were unlike anything that had been introduced to the scientific world, were designed to disprove the natural basis of science. Even today, relativity is accepted by some and rejected by others, but it continues to challenge the ideas of society. Einstein's theory of relativity has impacted society by aiding in the advancement of navigational technology, the progression of nuclear power and weapons, and challenging philosophy.



The theory of relativity results from two statements: 1. The speed of light is the same for all observers, regardless of their relative speeds. 2. The laws of physics are the same in any inertial frame of reference. Essentially, the 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.Given these two statements, Einstein showed how definitions of momentum and energy must be refined and how quantities such as length and time must change from one observer to another in order to get consistent results for physical quantities such as particle half-life. To decide whether his postulates are a correct theory of nature, physicists test whether the predictions of Einstein's theory match observations.The first statement--that the speed of light is the same for all observers--is the crucial idea that led Einstein to form his theory. It means that a quantity //c//, the speed of light, can be defined, as it is a fundamental constant of nature. The speeds of two objects are relative to each other. The second statement is a basic, though unspoken, assumption in science: the idea that rules of nature can be formulated which do not depend on the particular observing situation. However, this does not mean that objects behave in the same way on Earth as they do in space (SLAC).
 * Background Information:**



GPS was created by the United States Department of Defense in order to provide a satellite-based system for the U.S. military ("GPS and Relativity"). There are currently 24 satellites orbiting the Earth, all of which contain an atomic clock that "ticks" with an accuracy of one nanosecond. Without these satellites and their incredible precision, the GPS systems in cars and airplanes would not work. However, to be so precise, the ticks must reach an accuracy of 20-30 nanoseconds. Because of the general theory of relativity, this accuracy must be considered. Due to specal relativity, a person on the ground views the satellites relative to them as ticking more slowly. The theory predicts that the atomic clocks slow down clocks on Earth by about 7 microseconds ("GPS and Relativity"). In addition, general relativity predicts that clocks that are closer to a massive form will appear to tick more slowly than those at a greater distance. It also predicts that the atomic clocks pass clocks on Earth by 45 microseconds each day ("GPS and Relativity"). The effects of relativity must be taken into account with navigational technology; if they were ignored, the technology would not be accurate.
 * Navigational Technology:**

Under special relativity, momentum cannot be conserved from one reference frame to the next. This fact caused relativistic momentum to be defined. This type of momentum is conserved. For a long time, the formation of energy in nuclear reactions was portrayed as atomic mass converting to energy. Thus, nuclear power came about. Through the research of relativistic momentum, it was found that adding energy to an object does not make it accelerate. This is because the speed of light is the limit. But, by adding energy to the mass of the object, it increases with velocity. Relativity allows the development of nuclear technology to continue today. "Nuclear energy has helped alleviate a portion of our reliance on non-renewable resources for our energy needs. And as those needs increase and our resources are depleted, we will be continually drawn towards the promises nuclear energy has already fulfilled for other parts of the world that have more readily accepted it as a major energy supplier" (Arora).
 * Nuclear Technology:**

Einstein's theory of relativity have challenged the way traditional science views various physical aspects of the universe. Many ideas philosophers believed to be fixed or certain are, because of the theory of relativity, are actually neither fixed nor certain. Einstein expanded the scientific imagination and disproved the belief that there were absolute answers and ways of approaching aspects of life. He stated that "the laws of physics (and science) are the same for all observers, regardless of their speed, and that the speed of light was constant for all observers, regardless of their speed" (Arora). This leads to the conclusion that time is relative, a discovery that turned the moral philosophy of such scholars as Kant, Aristotle, and Mill upside-down. Even today, controversy continues over the truthfulness of the theory of relativity, but ultimately, belief depends fully on the individual.
 * Philosophy:**

Because of the development of the theory of relativity, the world has been augmented with advancement in navigational systems, progression in nuclear power and devices, and tests in moral philosophy. The accuracy of global positioning systems affects the lives of many people; thus, relativity is an essential part of the development of new technology. Nuclear energy, which depended on the creation of relativity, has contributed to the energy needs of the world. Einstein's theory has created controversy in the scientific world and has augmented moral philosophy. Whether you accept or reject relativity, there is no doubt that Einstein's idea has rocked the scientific world and challenged the minds of people everywhere.

This website, written by Hans Arora, fully explained the theory of relativity. It provided information about how his ideas changed the way people relate to science today. The article also includes information on how relativity has affect nuclear and navigational technology.
 * Works Cited:**

Arora, Hans. "Einstein’s Theory of Relativity: Implications Beyond Science? — Science in Society." __Northwestern University__. 3 Feb. 2009 http://209.85.173.132/search?q=cache:CCqSPZuVJ3kJ:scienceinsociety.northwestern.edu/content/articles/2008/research-digest/student-papers/einstein/einstein2019s-theory-of-relativity-implications-beyond-science+theory+of+relativity+%.

This website explains how relativity has fueled the creation of navigational technology, such as GPS systems. It explains how they work in specific details and how relativity relates to them.

"GPS and Relativity." __Google__. 3 Feb. 2009 http://74.125.47.132/search?q=cache:scO719ki--MJ:www.astronomy.ohio-state.edu/~pogge/Ast162/Unit5/gp. This website explains special relativity in easy-to-read, concise text. It also contains information about other topics that will help you understand relativity. This website is credible because it was created by Stanford University.

"Special Relativity." __Stanford__. 3 Feb. 2009 .