Time: It is incredible to think of the progress that human beings have made in understanding time since the last century. We went from ancient sundials to modern atomic clocks. Today we can follow the passage of a second more closely than ever before, but time remains an extremely complex topic. Thanks to visionary scientists, we are getting closer and closer to unraveling the secrets of the one who claims to be the “master of everything”.
The time for Newton
Isaac Newton, in the 17th century, created the thesis that time is like an arrow shot from a bow, traveling in a straight and direct line – and never deviating from its path. For him, a second had the same duration anywhere in the universe and nothing had a constant speed, not even the light. So he assumed that if the speed of light could vary, the time must be constant – going from one second to the next, with no difference in duration.
The weather for Einstein
Albert Einstein, in 1905, stated that the speed of light does not vary, being a constant that travels at about 299,792 kilometers per second. For him, time – the fourth greatness of the universe – was more like a river, leaking and flowing, depending on the effects of gravity and space-time. Time would increase and decelerate around bodies with different masses and velocities and, therefore, one second on Earth would not have the same duration in the entire universe.
But if the speed of light were really a constant, it would take a variable to change great distances across the universe. With its expansion and planets and galaxies moving on a gigantic scale, something would have to give in to allow these fluctuations – time. And after a brief passage from him, the theory proved to be totally accurate.