On the 29th of June, the most important astronomical discovery of 2023 was announced. The whole world of astronomy and physics is talking about this.I watched it live, but didn't choose to broadcast it live not to make any mistakes. I will try to explain this, which should excite people who are not into astronomy. Ever since Einstein, we've been suspecting the universe. From gravitational waves! The universe is full of gravitational fluctuations. The space-time fabric itself fluctuates. If you want to be a scientist and wonder what subject to work on, keep it in your mind. It was detected for the first time in 2015. Those who detected it were awarded the Nobel Prize in Physics in 2017, and I immediately prepared a video on that subject and explained the details to you, and now in 2023, such a way of detecting it has been found that we almost started to hear the whisper of the universe. More precisely, the voice that says "hmmm". So far we have recorded fluctuations in the universe as a result of the collision of two stars or two black holes. We almost heard the sound of those collisions. Yes, I say we almost heard it because these fluctuations occurred at specific frequencies that the human ear can hear. But no one could physically hear the voice like this. Because these ripples vibrate the fabric of space-time, not atoms or molecules. There is only one way you can physically hear this sound. And that is to go right next to the colliding black holes. Which I don't recommend to anyone. Please Don't. So how do we understand this issue? The best analogy I could find comes from a place we can easily see in our world, friends. From the oceans. Now imagine that you are in a big sea and think of the vast waters around you as what we call the fabric of space-time. And you are in a boat there. You may come across all kinds of waves around you, right? Sometimes the sea can be flat, sometimes slight fluctuations may occur, and sometimes you may have to grapple with huge waves. It's easy to sense low wavelengths when you're in such a small boat. Even in the smallest waves, your boat moves up and down. But it is not so easy to feel those very, very slow and large waves. You can only feel such big waves on a big ship. And on large ships, those little waves would have almost no effect. But there is such a huge fluctuation that is constantly occurring in the world that, a ship of such a size that you can feel it, could not be built. The tidal flow is a planet-sized fluctuation. Thus, gravitational waves are not so uniform too. The waves, first detected in 2015, were tiny enough to be felt from inside a small boat in the ocean. But you still have to use a boat to feel them, right? A craft of some sort. The Nobel Prize winners in 2017 are those who built that special craft. Special measurement craft. And it doesn't look like a tiny boat. It is a very special craft consisting of very sensitive lasers and mirrors that move in vacuum tunnels that are 4 kilometers/2.4 miles long in both directions. With this, it was proved that those tiny waves really do exist. Those tiny waves can occur when you throw tiny stones into the sea. Of course, instead of stones, they are formed by the collision of tiny black holes in space or by the collision of neutron stars. Don't be fooled by when I said tiny, of course, we're talking about star-sized masses. Now imagine the biggest waves that could ever occur in the ocean. For example, Tsunami waves. Such fluctuations occur in the fabric of space-time. Huge waves. Now you will say that detecting them is not easy? No, it's harder. We can detect them before they hit the shore but remember the boat and ship example. If you stand on a boat while such a huge wave is forming, it seems to you like nothing is happening. Because while the height of the wave is only a few centimeters, the length of the wave can reach hundreds of kilometers in deep seas. In order to feel the effect of such a wave and to measure it, it is necessary to use buoys and measuring instruments placed at certain points on the surface and at the bottom of the seas. Only in that way, we can understand that huge waves are formed according to the changes in the distance between them. Now let's think about the same thing for space. Let's imagine the fabric of space-time as a gigantic ocean. We cannot feel the immense fluctuations in this fabric from inside the tiny boat called the Earth.
We need those buoys placed in different parts of the ocean. But some gravitational waves are so large they are thousands of light-years across. therefore, it is necessary to distribute our space buoys in space on a very large scale. The scientists who made that very important astronomy discovery announced this week have been working on this subject for exactly 15 years and they discovered something very clever. Using pulsars as space buoys.
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Researched by: Ögetay Kayali
Presented by Baris Ozcan
27 сен 2024
