# can someone explain me the concept of time, like I know that black holes can distort time, but how?

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can someone explain me the concept of time, like I know that black holes can distort time, but how?

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Time is a relative unit of measure. So when things don’t work in a normal fashion I.E. gravity being so strong that light stays on, time isn’t the same there. If earths revolutions around the sun and Earth’s own rotation suddenly changed, time would have to change too.

It makes sense when you don’t separate time and space, it’s actually spacetime. Because they’re the same thing when gravity distorts space, it is also distorting time.

Time do not slow down around high mass objects example Black Hole. Its Just an phenomenon in which the shape of the Black Hole around the Event Horizon which make the observed object look to move slowly but actually it is moving at a constant speed. It’s just a Observation Illusion.

There’s still a lot we don’t understand about time. But what we do understand is that time and space are part of the same thing. They are directly tied together. Everything you do and experience isn’t just moving through space, but also through time as well. Fundamentally, everything in the universe travels through space and time at the same speed, and that speed matches the speed of light. This is why the closer you get to the speed of light, the more time slows down to someone outside watching you. You’re trading your speed in time for speed in space. This is why we say photons don’t experience time. All of their speed is in space and none of it in time.

Since time and space are tied together, what happens if you distort that space-time thing? Just like a balloon, if you inflate it you suddenly have more space-time to traverse. A black hole causes a massive distortion that basically stretches that thing. It’s like a treadmill. The closer you get to that black hole, the more space gets stretched under your feet. Everything in the universe travels at the same speed in space-time. In order to keep the same speed while space is getting stretched, you have to slow down in time because you have to go faster in space.

This is the general idea and I’m leaving out some things regarding relativity. But that should at least give you a general idea of why gravity impacts time. All gravity causes this, but it’s just really obvious when we talk about black holes.

There is no distinction between space and time. Our perception of three spatial dimensions and a temporal dimension is an artefact of observational limitations imposed by our own physiology.

Mass bends space-time which defines not only the spatial path that masses follow when near each other, but also their temporal path as well.

Another item to add is that time isn’t an absolute thing going on in the background… it’s relative. There’s not a universal clock that you can say is more right then any other.

Some areas of space-time are warped relative to others. Wherever there’s energy (including mass) you’ll find space-time warped relative to you.

Spoiler: I am not a physicist and this is just what little understanding I have of the subject.

Now, of course, time distortion doesn’t only happen around black holes. In fact the gravity of black holes isn’t any different than the gravity from any other object. The only difference is that the diameter of a black hole will be much smaller than the diameter of a star with comparable gravity, so objects can get much nearer to its center. But how does gravity work anyway?

Imagine a simple river. In the middle of the river the flow will be much faster than near the shores where the water will be slowed down by obstacles. If you placed to canoes on the river, on in the middle and the other one near the shore, the one in the middle would swin much faster and just pass by the other canoe. This is a comparison to two separate particles flying by a planet. One flies by really closely, where time goes slower, whereas the other one passes with some distance, where time will go faster. But most things are made up of more than one particle. Likes canoes.

What would happen if one of the paddlers would stick out their paddle and the other grabbed it, so that the canoes are locked together?

Well, the faster canoe in the middle of the river would be pulled towards the shore. It would move in a curved line as it is being held back by the slower canoe.

You can think of time as the water stream in the river. That flow of water in itself carries energy. Time in itself carries energy. When things get pulled to the shore, they lose some of their energy with which they move through time. This energy gets converted into the curved motion in space, which basically is gravity.

Oh, boy, you were asking about time… Hmm… I would think that as space and time are inseparable, they distort simultaneously.

Oh, man, I don’t think I added much to the discussion but it would also be too sad to just delete everything. So I’ll post it in the hope that someone finds it helpful.

You live in a 4 dimensional universe. Three dimensions are distance (spatial) and one is time (temporal). The speed of light (C) is the ratio of the distance in the temporal one, the one we call time, to the distance in the spacial ones, which we call distance. Every object exists as a unit velocity segment in this 4-space. Since a 4-space is hard to think about, let’s simplify (ELI5!) by considering the spatial dimensions in terms of our motion. Now we only have one spatial dimension, the direction we are moving. Turning (for the time being) doesn’t count. Next we graph our 2-space universe, with time on the vertical and distance on the horizontal. Every object is one unit from the origin on this graph, a quarter-circle. If a segment is aligned with the time direction (it’s vertical), the object’s spatial dimensions must be 0, this gives 0 speed in space and 1 second per second in time. If the velocity segment is oriented along the spacial dimension (horizontal) the object is moving at C, and since all segments are one unit long, it must be 0 in the temporal dimension. Thus photons move at the speed of light but do not experience changes in time. Gravity and other forces use energy to change the orientation of an object’s velocity segment, accelerating it in space and shortening the time element or decelerating it in space and lengthening the time segment.

C is a universal constant that describes everything’s velocity through spacetime. C in space = (roughly) 300 million m/s. C in time is 1 second per second. If you accelerate in space, you decelerate in time. If you are near a gravitational well, like Earth, gravity has the same effect on you as speed through space. So it slows down time. This causes your head and feet to age at different rates. As you approach a black hole, gravity gets more extreme, slowing down time.

Anything with gravity distorts time. Black holes just have a lot of gravity.

What does it mean to distort time? It means you change the effect of moving forward in time by 1 second. You can imagine time as a line on the ground, and every second you walk north along that line by 1 feet. So your total northward progress is one feet per second. Now imagine that the line goes up and then down a hill. Walking the same one foot up and down the hill actually results in less than one foot of progress northward. This ‘hill’ is the distortion caused by gravity. This is why you sometimes see the representation of spacetime distortion as a curved 2D sheet