Physics
Time — The 4th Dimension no one talks enough about.
Although we can’t see, feel, or even fully comprehend time, it’s very much real and ticking forward whether we like it or not.
The observable Universe is made up of 3 Dimensional Space. All objects, stars, planets, cars, trees, and humans including you and I have a length, breadth and height.
In our nice little cozy home of 3D space we can also observe 2D and 1D shapes as well. Let me explain this better with a graph.
3 Dimensional Space can be represented with the help of a x-axis, y-axis, and a z-axis (length, breadth, and height).
Any object which is 3 Dimensional can exist in this space, like the phone or laptop in your hands.
2 Dimensional Space can be represented with the help of the x-axis and y-axis.
Any object in this space only has a length and breadth, but no height.
A good example for 2 Dimensional space is everything you see on the screen right now. All the letters and symbols are 2 Dimensional objects.
1 Dimensional Space is represented with the help of only the x-axis. An object which is 1 dimensional can only exist across the x axis.
A line is the only possible 1 Dimensional Object. This is because this shape has only length, but no breadth or height.
Unfortunately the 4th Dimension isn’t as easy to comprehend as the other 3 Dimensions. You can guess why.
It’s because it’s impossible to observe the fourth dimension the same way we observe the third, second or first dimensions.
Even though scientists have tried to come up with ways to visualize the fourth dimension, it’s still rather complicated ( it’s called a tesseract, for those of you wondering) and it looks like this.
I’d rather not touch that topic for now because I can imagine most of you have a headache just from looking at it.
Instead, I have a rather interesting way we can look at the fourth dimension.
The world around us is constantly changing. Cars rushing down the street and people walking on the sidewalk, the sun rising in the east and setting in the west are all because of the passing of time.
Time is fluid and flows constantly, expanding in one direction on and on and on.
It’s safe to say that time is the fourth dimension that lets three dimensional objects flow through the course of time.
Without time, we would all be a bunch of objects lying still in space with no past, present and future.
Time shows us how things change and how different objects progress with time.
If this is difficult to wrap your head around, imagine taking a cube. After each second move the cube a little.
With each passing second, the cube is passing through the FOURTH DIMENSION because it’s changing its position in space as time passes.
If you really want to look at the Fourth Dimension on a graph then I think I might have a workaround for that.
Let’s squish all of 3D space into a 2D space (i.e on the x-axis and y-axis) — just for time being so I can show you something cool.
Now, our entire observable universe including everything you know and love, is stretched across this 2 dimensional space(x-axis and y-axis). Now, our z-axis is finally free to occupy the forth dimension — time.
As time progresses, the observable universe moves forward through time and we, as a result, experience all the effects of the unevitable clock that makes us age and progress with our lives.
The funny thing is as one moves through space faster and faster, time slows down for that person. If lets say, hypothetically of course, someone were to move at the speed of light (nothing moves faster that the speed of light), time will stop for that person. Wait? What?
Let’s say your friend, the one who loves adventures, gets shot into space at the speed of light and stays there for another uhh lets say 30 years.
When your friend comes back you would see that they didn’t change for one bit, but you on the other hand look like Gandalf the Grey. lol.
When your friend was shot into space at the speed of light, they experienced time differently to what you did on Earth. Since they were moving at such a high speed, time went went by suuuuper slow for that person. When they came back to Earth, they looked the same as they did 30 years ago because time never really ‘passed’ for them, it ‘stopped’.
To people on the Earth it would appear as though your friend was sent out into space for 30 years.
To your friend, they would be in utter shock to see everything changed on Earth. It’s as though they ‘time travelled’ into the future.
This is how we know it’s a possibility that one can supposedly ‘time travel’ into the future as long as that person is moving near the speed of light.
Time Travel into the past is where the trouble begins.
One can move forward into time if the move at lights’ speed but there is no way in which one can travel back into the past, or is there? Scientists have discovered something called wormholes, but that’s a story for another day.
Time always moves forward, whether we like it or not. A dimension that moves forward endlessly ever since the beginning of the universe. You can’t stop time (unless you’re moving as fast as light of course).
