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  • Essay / What time is it? A clarification on special relativity

    IntroductionWhat is time? We might be tempted to assume that everyone has a notion of time that is consistent with each other. Part of this “intuitive” notion of time contains the absolute nature of time – time flows at the same rate no matter what and is independent. Even if an apocalypse were to come to Earth, time would still pass casually. Yet in the early 19th century, Albert Einstein's "On the Electrodynamics of Bodies in Motion", or more affectionately known as the Special Relativity paper, confused our common notions of time, as well as space. The theory could explain many strange phenomena like Stella Abberation, Fizeau experiment, Michelson-Morley experiments. He also hypothesized a mass-energy hypothesis (which led to nuclear power plants) and predicted the relativity of simultaneity, both of which were later proven. It survived the demands of the scientific method and was on its way to becoming one of the most famous scientific papers. But the acceptance of such a brilliant theory was a warning: our notion of time and space would have to be revised into Minkowski space. time. Space can no longer be considered independent of time, nor vice versa. A famous and unintuitive consequence is that time is no longer absolute and independent of space. As an object's speed approaches the speed of light, the object would experience a slowdown over time with magnitudes described by Lorentz transformations. The two revisions of the concept of time by Special Relativity (namely the absoluteness and independence of time) are generally considered in the light of a better knowledge of the physical world. Slowing down time and therefore aging might be the holy grail for the beauty industry, but for a physics enthusiast... middle of paper ...... magnetism and if the magnet from the first scenario moves or not depends on the inertial reference frame at which we make our observation. If one sits still above the coil, one will see the magnet move and an electric field is induced around it. However, if one sits above the moving magnet, then for him, the magnet does not move and the coil moves towards the magnet. So, what we will observe is that the voice coil induces a magnetic field around it. So, is there a magnetic or electric field between the magnet and the coil (see figure 1)? What is objective truth? In Einstein's mind, he saw that the existence of an electric or magnetic field is relative. Only taken together as electromagnetic fields can we “attribute some sort of objective reality” to them. This, according to Einstein, led to his belief in the first postulate.