Death By Black Hole

Written By Khushi Choudhary
10-Kim%2CGyeongmin-80014985.jpg

Sunny Kim (ISB 10)

Spending her days at home due to the Novel Coronavirus outbreak, staff writer Sunny Kim would love to be anywhere outside of her house (a black hole, even😉).

In her second article for Buddy! “Death By Black Hole,” Sunny takes you right into the gaping maw of a black hole. What will you find there? Are there life lessons to be gleaned?

Dear Brave Traveler,

You were venturing out into space when you unfortunately came across the black hole that you are now orbiting.

From Nasa Gov

When a star ends its life, the outer layers explode, causing a supernova. For this black hole, its core could not overcome the immense gravity of the whole star, so it shrunk into a singularity - one point in spacetime with infinite density and mass. The black hole that you are orbiting is called a stellar black hole, which means it was formed from the death of a star.


From Nature (Research Journal)

Now, dear traveler, the fact that you are near a black hole does not necessarily mean that you will die. As long as you remain a certain distance from it, you will merely orbit it. But as soon as you cross the event horizon, no one knows what will happen to you. Even light, when it crosses the black hole, cannot come back. What happens if you get dangerously close to a black hole? Even before you go beyond the event horizon, the strength of gravity on your legs will be immensely greater than that strength on your head. Let’s assume that you, a short person of height 1.5m and weight 60kg, were orbiting one of the bigger stellar black holes scientists can detect (20 times the mass of the sun). Let’s also assume that the maximum force difference that your body could handle is 2000N, but only 1000N (the equivalent to being stepped on by a baby elephant) is enough to make you uncomfortable.

“…as you cross the event horizon, no one knows what will happen to you. Even light, when it crosses the black hole, cannot come back.”

The mass of the black hole indicates the radius of the event horizon: 60km in this case. If you are about 160 times farther away from the black hole than the event horizon, you will only feel mildly uncomfortable. However, just 126 times the distance away from the event horizon, you will no longer be able to survive. It doesn't matter if you get any closer. You will be split in half over and over again until you are a string of atoms heading towards the singularity.

However, you shouldn’t worry (well, not too much, anyway). Theoretically, black holes can disappear. In 1974, Stephen Hawking theorized that black holes are capable of evaporating. There are particles and antiparticles constantly appearing in the universe, only to annihilate each other almost an instant later. Each particle in a particle-antiparticle pair can either have positive or negative energy. Near the event horizon, one of the particles can get sucked in, and if the other lucky particle has positive energy, it can escape. This stream of escaping particles is known as Hawking Radiation, named after the scientist himself. The particle getting sucked in always has negative energy because of the gravitational force exerted by the black hole (the amount of energy a particle has decreases when there is a stronger gravitational force on it). Assuming that the black hole is not gaining mass from stars or any other materials, when it “consumes” enough of these particles with negative mass, the black hole will disappear. It does so at an accelerating rate, because it has a “higher” temperature, emitting more radiation. In its last moments, it will let out a sudden burst of energy and leave nothing behind. For the black hole that you are orbiting around, it will take approximately 1.67*10^71 years - way longer than the age of the universe - for it to completely evaporate.

“In its last moments, it will let out a sudden burst of energy and leave nothing behind.”


Unfortunately, you have already been sucked into a black hole by this point and have no hope of coming back out again, even if the black hole does disappear. But Stephen Hawking’s theory leads us to another idea: nothing in this universe is definite. The stars born at the start of the universe meet their demise as a black hole, and even the almighty black hole eventually evaporates. Compared to the stars, our lives are inconsiderably short. What can we do to be of any significance to this vast universe?

The simple answer is we cannot. However, we can strive to become better versions of ourselves using the short amount of time allotted to us. Friedrich Nietzsche, a German philosopher of the 19th century, proposed that the purpose of humans was the “will to power.” He believed that we should strive to set high goals and try as hard as we can to achieve them. Only then will our power increase. The power that Nietzsche fervently advocates is open to interpretation; some suggest that it is the power to influence one’s surroundings to become better versions of ourselves. If that is the case, us travelers of the universe can fulfill our goal - the will to power - by doing just that.

As the black hole approaches slowly to death, it sends out a burst of light in its last moments, illuminating the dark sky. It leaves behind a beacon for future generations to marvel at. Just as the black hole leaves its legacy, we can also practice our best form of self-overcoming and possibly create an everlasting reverberation in our children and their progeny.


Screen Shot 2020-02-20 at 19.43.25.png
Screen Shot 2020-02-20 at 19.43.31.png
Khushi Choudhary
Previous

Why You Think You Sound Horrible on Recording
Next

The Coronavirus From The Outside