What is space and time?
In physics, spacetime is any mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum. Spacetime diagrams can be used to visualize relativistic effects such as why different observers perceive where and when events occur differently. Another corollary of special relativity is that, in effect, one person’s interval of space is another person’s interval of both time and space, and one person’s interval of time is also another person’s interval of both space and time.
Thus, space and time are effectively interchangeable, and fundamentally the same thing (or at least two different sides of the same coin), an effect which becomes much more noticeable at relativistic speeds approaching the speed of light.
Einstein’s former mathematics professor, Hermann Minkowski, was perhaps the first to note this effect (and perhaps understood it even better than Einstein himself), and it was he who coined the phrase “space-time” to describe the interchangeability of the four dimensions. In 1908, Minkowski offered a useful analogy to help explain how four-dimensional space-time can appear differently to two observers in our normal three-dimensional space.
He described two observers viewing a three-dimensional object from different angles, and noting that, for example, the length and width can appear different from the different viewpoints, due to what we call perspective, even though the object is clearly one and the same in three dimensmc2 s.
Einstein remarked, “For us physicists, the distinction between past, present and future is only an illusion, however persistent”, and these concepts really do not figure at all in special relativity. Similarly, our whole conception of space becomes unreliable as the relativistic effects of length contraction become apparent at high relative speeds.
But the malleability and blurring of space and time also has implications for other aspects of physics. Just as Maxwell had shown that the electricand magnetic fields, once considered completely separate entities, were both just part of a single seamless entity known as the electromagnetic field, likewise (although perhaps more difficult to grasp and perhaps more unexpected) energy and mass turn out to be just different faces of the same coin, a connection encapsulated in Einstein’s justifiably famous formula, E = mc2
As the Sun pumps out energy and light, it actually also loses some of its mass, although very slowly (less than 0.1% since its birth). As a comet’s path passes near to the Sun, a tail of glowing gases billows out away from the Sun. Both of these examples suggest that the energy (photons) leaving the Sun actually weighs something, actually has mass, even if very little. Although photons of sunlight have no intrinsic mass (otherwise, as we will see, they would be unable to travel at the speed of light), they must have an “effective mass” by virtue of their energy in order to be able to push a comet’s tail.
If a body with mass is pushed ever closer to the speed of light, the body would have to become harder and harder to push, so that its speed never actually reached or exceeded the speed of light, which we know to be the de facto maximum speed. In fact, by extension, if a material body were ever to reach the speed of light it would effectively have to have acquired an infinite mass. As a body approaches the speed of light, then, the energy put into pushing the body clearly cannot be used to increase its velocity and must therefore go somewhere else.
If anybody want to know more about it please comment 💬💬
Because I have lot of things and knowledge about it & I'm happy to share with you..
In physics, spacetime is any mathematical model that fuses the three dimensions of space and the one dimension of time into a single four-dimensional continuum. Spacetime diagrams can be used to visualize relativistic effects such as why different observers perceive where and when events occur differently. Another corollary of special relativity is that, in effect, one person’s interval of space is another person’s interval of both time and space, and one person’s interval of time is also another person’s interval of both space and time.
Thus, space and time are effectively interchangeable, and fundamentally the same thing (or at least two different sides of the same coin), an effect which becomes much more noticeable at relativistic speeds approaching the speed of light.
Einstein’s former mathematics professor, Hermann Minkowski, was perhaps the first to note this effect (and perhaps understood it even better than Einstein himself), and it was he who coined the phrase “space-time” to describe the interchangeability of the four dimensions. In 1908, Minkowski offered a useful analogy to help explain how four-dimensional space-time can appear differently to two observers in our normal three-dimensional space.
He described two observers viewing a three-dimensional object from different angles, and noting that, for example, the length and width can appear different from the different viewpoints, due to what we call perspective, even though the object is clearly one and the same in three dimensmc2 s.
Einstein remarked, “For us physicists, the distinction between past, present and future is only an illusion, however persistent”, and these concepts really do not figure at all in special relativity. Similarly, our whole conception of space becomes unreliable as the relativistic effects of length contraction become apparent at high relative speeds.
But the malleability and blurring of space and time also has implications for other aspects of physics. Just as Maxwell had shown that the electricand magnetic fields, once considered completely separate entities, were both just part of a single seamless entity known as the electromagnetic field, likewise (although perhaps more difficult to grasp and perhaps more unexpected) energy and mass turn out to be just different faces of the same coin, a connection encapsulated in Einstein’s justifiably famous formula, E = mc2
As the Sun pumps out energy and light, it actually also loses some of its mass, although very slowly (less than 0.1% since its birth). As a comet’s path passes near to the Sun, a tail of glowing gases billows out away from the Sun. Both of these examples suggest that the energy (photons) leaving the Sun actually weighs something, actually has mass, even if very little. Although photons of sunlight have no intrinsic mass (otherwise, as we will see, they would be unable to travel at the speed of light), they must have an “effective mass” by virtue of their energy in order to be able to push a comet’s tail.
If a body with mass is pushed ever closer to the speed of light, the body would have to become harder and harder to push, so that its speed never actually reached or exceeded the speed of light, which we know to be the de facto maximum speed. In fact, by extension, if a material body were ever to reach the speed of light it would effectively have to have acquired an infinite mass. As a body approaches the speed of light, then, the energy put into pushing the body clearly cannot be used to increase its velocity and must therefore go somewhere else.
If anybody want to know more about it please comment 💬💬
Because I have lot of things and knowledge about it & I'm happy to share with you..
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