Time...The only thing we can never stop, and that doesn't come back once spent. Our lives... Whether you're the richest person in the world or the cover of Forbes as "The most powerful person in the world," the only thing you can't change. We have a hard time even describing it. From philosophers to writers, from scientists to artists, we all have different explanations for time. But we don't have a consensus on what it is. We all live, experience, but yet do not grasp the meaning. How strange, isn't it? As if we weren't confused enough, Einstein had these words about time: " People like us," he said, " who believe in physics know that the distinction between past, present and future is only a stubbornly persistent illusion." Is time really just an illusion? Why can't it be identified? How would you describe it? Time is what it takes for an event to happen. It takes time for a movement to exist. We go from one point to another at a given time. But what is movement? For it, time is what needed. We use movement when defining time and time when defining movement. Well, it seems that it is not easy to define time by itself. Time is also relative. While an hour passes for me, for someone else near the black hole it may be only a minute. Or perhaps it could only be 30 seconds for someone else traveling at near-light speed towards Andromeda. But it's strange, isn't it? None of these people would feel this slowdown in time. We all perceive time in the same way. Whether we're next to a black hole, or traveling through space at a speed close to the speed of light, or simply stretching by the pool on Earth while sipping our coffee. Because everything around us, from the blood in our veins to the clock ticking on our arms, slows down,. We perceive time in the same way. However, two different times flow in two different corners. So much so that if someone were to play with the time settings of the universe and slow everything down and speed up at once, we wouldn't even be able to notice it. Physicists are still thinking about what time is. Moreover, they call it not just time, but also space-time. We have known since Einstein that time and space are intertwined. But why is there only one dimension when it comes to time whereas there are 3 dimensions when it comes to space as in width, length and height? And why does time always only flow forward? Whereas, we can go both forward and backward in 3 space dimensions. Why doesn't this happen when it comes to time? Many physicists explain this in terms of entropy. Second law of thermodynamics. entropy in a system increases over time. The systems in our universe show a transition from order to disordered. This transition happens over time and flows in only one direction. The arow of time. It has the tendency to be disordered. Therefore, the disorder increases over time. So the increasing disorder must be telling us that time is flowing forward. The past hypothesis. If entropy is constantly increasing, there should have been a lower entropy yesterday. Why did it had a lower entropy yesterday? Because the day before that it had even lower entropy. That's how it goes backwards and backwards until finally it comes to the time of the big bang, and claims that the universe started from a very low entropy state. So why was that? Or did it have to be like this? A big question mark. What if we could go beyond the speed of light? Of course, there are very crazy ideas in this part, which remains highly speculative. For example, let's go back to our previous question of, "Why are there 3 space but 1 time dimensions?"
Of course, it's not just that. There are also 11-dimensional supergravity theories. Some researchers are even bold enough to say that beyond the speed of light there is only one space, three time dimensions. So, they argue, when we go beyond the speed of light, the concept of time and space changes.
I'm not even going to argue about what even that means anymore, or we would go crazy! But physicists almost agree that we cannot go back in time. They are obviously very confused about the time itself.

Researched and Written by: Ögetay Kayalı
Organized and Presented by: Barış Özcan
Edited by: Alperen Çatak
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