The concept of moving between different points in time in a manner analogous to moving between different points in space, generally using a theoretical invention known as a "time machine". Time travel is a recognized concept in philosophy and fiction, but has a very limited support in theoretical physics, usually only in conjunction with quantum mechanics or Einstein–Rosen bridges.
A science fiction novel written in 1895 called The Time Machine, by H. G. Wells, was instrumental in moving the concept of time travel to the forefront of the public imagination, but the earlier short story "The Clock That Went Backward", by Edward Page Mitchell, involves a clock that, by means unspecified, allowed three men to travel backwards in time. Non-technological forms of time travel had appeared in a number of earlier stories such as Charles Dickens' A Christmas Carol. Historically, the concept dates back to the early mythologies of Hinduism (such as the Mahabharata). More recently, with advancing technology and a greater scientific understanding of the universe, the plausibility of time travel has been explored in greater detail by science fiction writers, philosophers, and physicists.
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