Aaron Jiang ’23
The end of the world: one whose date has been prophesied who knows how many times with all of them, without exception, being false. Whether you desire the end or not(seriously, if you do, it is in your best interest to please seek the Guidance Department), if a black hole somehow makes a visit to our solar system, nothing will remain. These monsters were only theoretical in the last century and have only become confirmed to exist this century. We now know a lot more about these mysterious creatures that lurk in the depths of our enigmatic universe mainly thanks to the late Professor Stephen Hawking. However, what’s scary is that we still have a lot of unknowns regarding the nature of their existence. Our knowledge of this matter is just all superficial so far, and we don’t even know what we don’t know! Part of their mysteriousness is that they are so dense that their gravitational pull gives no chance for even light to escape their wrath, which is a huge reason for their late discovery.
Well, that’s exactly the reason for the excitement whenever such mysterious nature exhibits new revelations: supermassive black holes recently studied allude to fingerprints left from the Big Bang. We all, in modern astrophysics, understand the general process of formation of a black hole. When a giant gas star comes to the end of its life, that is when its fuel runs out, it will transform itself into a black hole that’s at least a few dozen times the mass of our sun, and, with luck, it will eventually gain supermassive status after merging with other black holes and eating all surrounding celestial bodies that the beast stumbles upon. These supermassive black holes, well, are massive to say the least: ranges from millions of times of solar mass(mass of our sun) as the smallest to those found in the center of huge galaxies, which are all exceeding hundreds of billions times of solar mass. For instance, our very own Milky Way houses such black holes: Sagittarius A* is located at the center of our galaxy at 4.3 million solar mass, which is one of the smallest supermassive black holes. To place that into perspective, TON 618 is another supermassive black hole that’s 66 billion solar mass, which is absolutely horrifying to think about. Fortunately, it is well over 10 billion light years away.
These all make sense to us as these black holes are usually found in the more modern portion of our universe. In other words, the light surrounding these black holes travels less in time to reach Earth, which entails that they have had billions years of age and history to garble all surrounding celestial bodies and other black holes to gain supermassive. However, just recently astronomers have discovered supermassive black holes at the very early portion of our universe whose distance is at least 12 billion light years away from us since the universe is believed to be 13.8 billion light years old due to the light left by the initial Big Bang that started it all. Already, we’ve known over 200 black holes that were in existence when the universe was just under one billion years of age. More incredulously, we’ve also discovered one, Quasar J0313-1806 namely, whose existence was already of a supermassive black hole status when the universe was just 670 million years old.
All of this news is not only baffling to scientists, but it implies other crucial knowledge that humanity will soon uncover! A supermassive black hole takes time: star forms, star dies, star turns into black hole, black hole eats for quite some time to become supermassive. In the case of Quasar J0313-1806, it simply just isn’t possible, which is a paradox for now. Most stars weren’t even formed when the universe was just 670 million years old, much less dying all turning into a black hole gradually. Therefore, these supermassive black holes discovered in the early universe aren’t for sure given birth by normal astrophysical processes.
There is an answer to this paradox that scientists came up with: primordial black holes, which entails black holes that form at the early instantaneous moments after the Big Bang. It makes sense because the only other explanation is that these supermassive black holes were somehow formed instantly at the moment of the Big Bang with all the chaos. They didn’t need to be a giant star at first unlike black holes in the modern universe. Unfortunately, this theory almost runs into a dead end also because the said black holes(primordial black holes) were never found. Astronomers have spent decades searching through probes such as the cosmic microwave background, which is the light left when the universe was just 380,000 years old! To no avail, such theoretical creatures perchance aren’t practically in existence at all. I said “almost” earlier because there were exceptional findings that could be classified as a primordial black hole that forms at the first second after the Big Bang. However, until further studies, we shouldn’t make the call now. Especially when NASA’s exciting James Webb Space Telescope is launching in a couple months from now! It might very well be up to the task of observing far into the universe back in time to uncover the secrets of these primordial black holes and their formation at the moment of Big Bang, which in itself is a invaluable window to peek at this earliest moment of the Big Bang, the reason for everything’s existence today.