The door that cannot be entered

(Photo: oorka/Shutterstock)

“Black Holes are the most mysterious objects in the universe.” Their gravity is absolute. They used to be science fiction, but we have found them. In fact, they are enormous in amount. It devours everything that manages to come across its path. Black holes are the end point of everything. It is the end point of a star, a matter, space, energy, time etc. Some astronomers think that they could be a gateway to the parallel universe. They get their power from one of the fundamental forces of nature - Gravity. The force of gravity is infinite. It sucks everything including light. Its effective force can be imagined as a waterfall and gravity is the river flowing towards the waterfall. Away from the waterfall, the strength of the current is weak and the rower can row throughout it efficiently. But towards the waterfall the strength is maximum and it is not possible to escape from falling, no matter how hard we row.

Birth of a Black Hole:

Black holes are born from massive weighing stars. It is the only source that creates so much gravity. When stars weighing more than 20 to 25 times than our sun, gravity crushes its core from inside releasing a shockwave towards star’s outer layer which results in hypernovas. This is the birth of a black hole. When explorer occurs, the core of the star starts to suck up all the contents and the gravity in the center of the star becomes huge. The core shrinks to a very small region.

When the stars explode they produce 100 times more energy than our sun will produce over its lifetime, leaving out a newly formed black hole and two jets of strong rays called the gamma rays. Gamma rays last only a few seconds and fry anything that comes in their path. They are the most illuminated objects in the world. Most of the gamma-ray bursts occur outside our galaxy. They help us recognize how many black holes are being formed. NASA launched the SWIFT telescope to study gamma-ray bursts.

To understand the black hole and what lies beyond it, one needs to traverse it. Laws of physics breakdown near the edge of a black hole. Gravity becomes infinite and time stops. We cannot send humans to study the black holes neither can we send a robotic probe towards it. The edge of a black hole is known as “event horizon”. It is named so because it separates space between two regions. As we reach the event horizon, gravity becomes stronger. Our feet are closer to the effect of gravity than our head, as a result of which gravitational force experienced by our feet is comparatively more than our head. Eventually, our body starts to stretch and we would get ripped apart. The same thing would happen if we send a robotic probe. This process is called “Spaghettification”. Let us consider that the robotic probe was strong enough to withstand the gravitational pull, but as soon as it comes close to the event horizon, gravitational force becomes so extreme that it stops time. If we notice the probe from outside, it would apparently appear to stop. But near the event horizon, the probe is actually moving through space-time. We would never notice an object fall through the black hole. After entering the black hole, if the probe turns its camera backward, it would see the light getting sucked in. And as the probe enters the black hole at first it would notice everything black nut later it would encounter the most bizarre place in the universe.

The heart of a black hole is amazingly dense and scientist call it “Singularity”. It actually means - unknown, and they call it so because they cannot comment on anything that happens there, as the laws of physics break down. Singularity is the point of infinite gravity and region of no space and time.

Black holes have been the most mysterious object in the universe which has made humans question again and again. Renowned scientists like Stephen Hawking, spend their lives discovering groundbreaking properties of the black hole. These discoveries have opened a new gateway to science, full of new facts and rules. By studying black holes our world can crack many other universe codes and unravel its mystery.

Regards,

Muskaan Maurya

B.tech - Computer Science and Engineering

First Year

Heritage Institute Of Technology -Kolkata

Sources:

• How the universe works - Discovery Channel
• World Science Festival - youtube
• Black holes and baby universes- Stephen Hawking.
• Wikipedia