A Black hole is a region in space where gravity is so intense. Even light can’t escape from it. These monsters swallow anything and everything within their reach, and they have their crowns at the centre of all spiral galaxies.
These bodies continue to fascinate scientists and space enthusiasts equally, providing a glimpse into the most extreme environments in the universe, and they are considered an endless area of study.
THE BIRTH OF A BLACK HOLE:
Black holes are created when a star much larger than our sun collapses under its own gravity at the end of its life cycle.
As the initial mass of the star is enormous, the contraction of the core is driven by forces are also enormous, which results in an intensification of the repulsive forces of the neutrons. This results in the squeezing of the entire mass of the star’s core into the size of a nucleus of an atom. It’s even hard to imagine how dense such an object could be!!! The gravitational force of such a dense object; prevents light from escaping.
In this huge universe, nothing can overwhelm the speed of light, as a blackhole could trap light, nothing can escape from it either.
Types of Black Holes: There are various types of black holes, each with different characteristics. These include stellar mass, intermediate mass, supermassive and even theoretical primordial Black holes.
Stellar mass Black holes are formed when the massive stars collapse at the end of their lives.
A Supermassive black hole may form by merging with other black holes or even from the direct collapse of massive gas clouds
Structure of a black hole:
Any Celestial body in the neighbourhood of a black hole is drawn into its atmosphere, that is why we call it a cosmic sinkhole. This results in the spinning of objects around a black hole, which forms an accretion disc. The point of no return is referred to as an event horizon. At the very centre, all the mass is crushed into a single point called a singularity. The radius of this Singularity is known as the Schwarzschild radius.
(Image credit: NASA)
Finding cosmic monsters
Black holes don’t emit light, which makes them invisible to the naked eye. Our scientists have strategies to track them out by various methods, like:
Observing their gravitational influence
Snapping their event horizon
Searching for an accretion disc
Gravitational lensing, where a Black monster’s gravity bends and distorts light behind it, making distorted images.
JAMES WEBB TELESCOPE will innovate our understanding of the universe by observing early universe Black holes and their formation with extraordinary clarity.
(Image credit: NASA)
(Image credit: ESA)
Excitingly, recent discoveries are expanding our understanding of black holes. In February 2025, scientists using DESI [Dark Energy Spectroscopic Instrument] uncovered a huge number of intermediate Black holes and dwarf galaxies with Black holes.
DEATH OF A BLACK HOLE:
HAWKING RADIATION AND BLACK HOLE EVAPORISATION
The Black Hole slowly shrink as it loses tiny amounts of energy through a theoretical process called Hawking radiation.
Hawking radiation connects Thermodynamics, Quantum mechanics, and General relativity, which are fundamental to physics. To unlock deeper cosmic mysteries, scientists are still looking for experimental proof of Hawking radiation.
[Image credit: Physics Feed]
Now, let’s delve into the topic of “ How black holes evaporate?”
Black hole evaporation is a fascinating process predicted by Stephen Hawking, called Hawking radiation. Quantum mechanics proposes that Black holes slowly lose their mass over time, and can eventually disappear.
Black hole evaporation arises due to quantum effects near the event horizon, where quantum particles can form. Out of these particle pairs, one falls into the Black hole, while the other escapes as real radiation. This escape process intends a Black hole to lose energy, and slowly shrink over time. Results in emitting more radiation and heat. This takes several billion years to come to an end.
IMPACT OF BLACK HOLES ON SPACE TIME
As stated by Einstein’s General Theory of Relativity, the complex structure of a Black hole, being incredibly dense, tends to be the most extreme distortions on the fabric of space-time.
The impacts include:
Gravitational time-dilation:
It defines that time moves slower in stronger gravity compared to weaker gravity.
Tidal effects and “INTERSTELLAR”- the science behind the spectacle:
Christopher Nolan’s 2014 film “INTERSTELLAR“ excellently showcases the extreme physics of Black holes. Including the scene of tidal effects, affected by intense gravitational forces near immense celestial bodies. It is a Phenomenon that occurs due to differences in gravitational pull. It is often referred to as spaghettification.
Black hole mergers producing gravitational waves:
Ripples across space time, referred to as gravitational waves, are produced when two Black holes merge. The LIGO [Laser Interferometer Gravitational-wave Observatory]
detected these gravitational waves in 2015.
[Image credit: www.ligo.caltech.edu]
Singularity effects:
At the singularity, the spacetime breaks down, and the density becomes infinite. The laws of physics cease to function, making it mysterious in astrophysics.
By
K. Sai Kruthi