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'''General Reference''' is a category of work that provides the widest possible '''frame of reference''' for participants in [[The Nordan Symposia]].  

'''General Reference''' is a category of work that provides the widest possible '''frame of reference''' for participants in The [[Nordan Symposia]].  

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A '''frame of reference''' is a particular [[perspective (visual)|perspective]] from which the [[universe]] is observed. Specifically, in [[physics]], it refers to a provided set of [[Coordinate axis|axes]] from which an [[observation|observer]] can measure the position and motion of all points in a system, as well as the [[orientation (geometry)|orientation]] of objects in it.  

A '''frame of reference''' is a particular [[perspective (visual)|perspective]] from which the [[universe]] is observed. Specifically, in [[physics]], it refers to a provided set of [[Coordinate axis|axes]] from which an [[observation|observer]] can measure the position and motion of all points in a system, as well as the [[orientation (geometry)|orientation]] of objects in it.  

It is important to note that there were a number of assumptions made about the various inertial frames of reference. Newton for instance believed in a concept known as universal time. This is best explained by an example. Suppose that you own two clocks, which both tick at exactly the same rate. You synchronise them so that they both display the exact same time. The two clocks are now separated and one clock is on a fast moving train, travelling at constant velocity towards the other. According to Newton, these two clocks will still tick at the same rate and will both show the same time. Newton says that the rate of time as measured in one frame of reference should be the same as the rate of time in another. That is, there exists a "universal" time and all other times in all other frames of reference will run at the same rate as this universal time irrespective of their position and velocity. This concept was later disproven by Einstein in his [[special theory of relativity]] (1905) where he developed transformations between inertial frames of reference based of their relative displacement and relative velocity ([[Lorentz transformations]]).

It is important to note that there were a number of assumptions made about the various inertial frames of reference. Newton for instance believed in a concept known as universal time. This is best explained by an example. Suppose that you own two clocks, which both tick at exactly the same rate. You synchronise them so that they both display the exact same time. The two clocks are now separated and one clock is on a fast moving train, travelling at constant velocity towards the other. According to Newton, these two clocks will still tick at the same rate and will both show the same time. Newton says that the rate of time as measured in one frame of reference should be the same as the rate of time in another. That is, there exists a "universal" time and all other times in all other frames of reference will run at the same rate as this universal time irrespective of their position and velocity. This concept was later disproven by Einstein in his [[special theory of relativity]] (1905) where he developed transformations between inertial frames of reference based of their relative displacement and relative velocity ([[Lorentz transformations]]).

It is also important to note that the definition of inertial reference frame (defined as one in which a free particle travels in a straight line at constant speed) does not include a requirement that the inertial reference frame must exist in three dimensional Euclidean space. This was another of Newton's assumptions which would later be disproven. As an example of why this is important, let us consider the [[Non-Euclidean geometry]] of a sphere. In this geometry, two free particles may begin at the same point on the sphere, travelling with the same constant velocity in different directions. After a length of time, the two particles will collide at the opposite side of the sphere. Both free particles were travelling with a constant velocity and no forces were acting. No acceleration occurred and so Newton's first law held true. This means that the particles were in inertial frames of reference. Since no forces were acting, it was the geometry of the situation which caused the two particles to meet each other again. In a similar way, it is now believed that we exist in a four dimensional geometry known as [[spacetime]]. It is believed that the curvature of this 4D space is responsible for the way in which two bodies with mass will meet together even if no forces are acting. In Newtonian mechanics, this is explained by a force known as gravity.

It is also important to note that the definition of inertial reference frame (defined as one in which a free particle travels in a straight line at constant speed) does not include a requirement that the inertial reference frame must exist in three dimensional Euclidean space. This was another of Newton's assumptions which would later be disproven. As an example of why this is important, let us consider the [[Non-Euclidean geometry]] of a sphere. In this geometry, two free particles may begin at the same point on the sphere, travelling with the same constant velocity in different directions. After a length of time, the two particles will collide at the opposite side of the sphere. Both free particles were travelling with a constant velocity and no forces were acting. No acceleration occurred and so Newton's first law held true. This means that the particles were in inertial frames of reference. Since no forces were acting, it was the geometry of the situation which caused the two particles to meet each other again. In a similar way, it is now believed that we exist in a four dimensional geometry known as [[spacetime]]. It is believed that the curvature of this 4D space is responsible for the way in which two bodies with mass will meet together even if no forces are acting. In Newtonian mechanics, this is explained by a force known as gravity. [http://en.wikipedia.org/wiki/Frame_of_reference]

[[Category: General Reference]]

[[Category: General Reference]]