We speak of time and space as interchangeable things. But still it seems strange to us that there is something in common between passing minutes, hours, days and distance. This is the distance the Earth turns in 24 hours.

Time and a look at the stars

Year is the distance that the earth travels around the sun. A look into space is a look into the past. Light is the fastest messenger in the world, but he also needs some time to reach us. When we look at the Sun, we see it as it was eight minutes ago. We see the star closest to us as it was four years ago, and the more distant stars billions of years ago.

Gravity and Time

Gravity, which bends space like a ductile film over clots of matter, also affects time. Gravity slows down the passage of time. The stronger the gravitational field, the slower the time flows.

At the very surface of the Earth, where gravity is higher than in outer space, the clock is very small, but lagging behind compared to the clock placed in space. All this is of course relative. For each observer who is close to any of these watches, nothing changes subjectively. The clock does not run forward and do not lag behind. The same is true if people of the same age are placed in gravitational fields of different strengths: after a while, a difference in age will be revealed.When they are brought together again, their age will be unequal, they will cease to be peers.

Black hole and time

Based on the laws of the universe, the theory of relativity considers space and time as something single - space-time. Near a black hole that bends the space so much that it begins to resemble a black hole in form, time creeps, as on objects flying at about light speed. If an object falls into a black hole, then time will stop for it, as for an object flying at the speed of light.