Is time real? © Getty Images

Is time an illusion?

There are some theories in physics that suggest that our perception of time isn't real and that it is the universe's greatest illusion.

Asked by: Anonymous

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The currently accepted view of physics is that time is as real as space. Time is sometimes thought of as ‘just’ the fourth dimension, but it seems as though it is somehow different from the three dimensions of space. For a start, it appears to flow in only one direction. Since Einstein, physicists have used the concept of ‘spacetime’ to combine all four into a single continuum, but time is always treated as a different sort of dimension. If you plot a graph of the number of dimensions of space against the number of dimensions of time and consider the known physical laws in each of these hypothetical universes, it turns out that the only universe that is stable and could support us, is the one that has three dimensions of space and one of time. In a universe with three time dimensions and only one space dimension for example, the speed of light would be the lower limit for all motion.


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