The Bond: Connecting Through the Space Between Us

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physics

Science that deals with the structure of matter and the interactions between the fundamental constituents of the observable universe. Long called natural philosophy (from the Greek physikos), physics is concerned with all aspects of nature, covering the behaviour of objects under the action of given forces and the nature and origin of gravitational, electromagnetic, and nuclear force fields. The goal of physics is to formulate comprehensive principles that bring together and explain all discernible phenomena. See also aerodynamics; astrophysics; atomic physics; biophysics; mechanics; nuclear physics; particle physics; quantum mechanics; solid-state physics; statistical mechanics.

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space-time

Single entity that relates space and time in a four-dimensional structure, postulated by Albert Einstein in his theories of relativity. In the Newtonian universe it was supposed that there was no connection between space and time. Space was thought to be a flat, three-dimensional arrangement of all possible point locations, which could be expressed by Cartesian coordinates; time was viewed as an independent one-dimensional concept. Einstein showed that a complete description of relative motion requires equations that include time as well as the three spatial dimensions. He also showed that space-time is curved, which allowed him to account for gravitation in his general theory of relativity.

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