Time in physics is simply defined by its definition: time is how a clock reads. In classical, no-relativity physics, it’s a scalar value (often called the tiniest scalar), representing time as the passage of one complete measure (a sub-period). This can be thought of as the definition of time because it closely relates to the definition of time. In this case, time is simply the difference between the beginning of one synchronized measure and the ending of another.

Einstein’s general relativity (GCD) demonstrated that time and space are actually different and not equivalent. His special theory of relativity (SPR) generalized time and space to include time and matter as well as gravity. This theory explained time and accelerated motion as arising from a single source at a single position. The SPR further explained that a single source of time can be compared to a set of reference frames that contain independent reference frames. This concept was later adopted and became the classic model of the universal law of time.

Galilean relativity describes time as an optical illusion caused by motion. Galilean time does not correspond to any real external reference frame. In fact, when observing clocks, observers only see a rotating globe where the clocks appear to have been traveling in separate directions.

Einstein’s special theory of relativity made it possible for clocks to be used to measure motion. To do this, clocks could be made to run on reference frames such as disks with atomic weights placed within them or on the very small masses around them. Einstein’s special theory of relativity solved the problem of time dilation by assuming that each reference frame was stationary, while each moving reference frame was deformed due to its motion relative to the rest. This assumption solved the problem of time dilation, as well as the Einstein-Podolsky paradox.

Albert Einstein was one of the most outstanding physicists of all time. His special theory of relativity not only explained time and the cosmos as we know it, but also gravity. It predicted the existence of space-time, which he called a worm hole. Einstein’s special theory of relativity further explained the accelerating expansion of the universe and the nature of matter. The Nobel Prize winner’s special theory of relativity further provided solutions to the problems of general relativity. Albert Einstein was also an outstanding scientist, specializing in both physics and mathematics.

If time travel is possible, then someone could possibly visit the past and future using a clock. A clock could be built to transport information from the present to the past or the future. One way to do this would be to build a time machine. A time machine is a device that would allow someone to go back in time using a stolen from today. Another way would be to use a space-time continuum to warp the clock to go back in time. If a time machine does exist, there is certainly no stopping it from transporting information from our present into the past or the future.