Singularity
Okay. So it's 3 AM in the night, and insomnia is peaking! But I found something interesting on the internet.
Black holes. I remember being in middle school, completely confused about what they are. And the way they were shown in Interstellar, it was the coolest thing ever for me, and guess what? It still is.
(Spoiler alert!) As said in Interstellar, Love transcends both space and time... and so does gravity. Cooper could pass the quantum data to Murph because of love, he knew she would decode it from the fifth dimension.
A black is simply a region where gravity is so strong that even light cannot escape. At it's core lies singulartiy (so infinitely dense that the known laws of physics break down), wrapped around by the event horizon.
Enter Einstein, two radical theories that changed the way we see the universe: Special and General Relativity.
Special Relativity (1905) reshaped our understanding of space and time. It showed that the laws of physics are the same for all observers moving at constant speeds, and that the speed of light is the same for everyone, regardless of their motion. This led to surprising conclusions: time can pass more slowly for someone moving near the speed of light (time dilation), and lengths can appear shorter (length contraction). These effects are quantified by the Lorentz factor: $$\gamma = \frac{1}{\sqrt{1 - \frac{v^2}{c^2}}} $$ One of the most famous outcomes of this theory is the equation $$ E = mc^2 $$ which reveals that mass is simply a form of energy. This principle plays a crucial role in astrophysics, helping to explain how stars release energy through nuclear fusion and ultimately how they can collapse under their own gravity to form black holes once their fuel runs out. Read more
General Relativity (1915), expanded these ideas by including acceleration and gravity. Rather than viewing gravity as a force pulling objects together, Einstein described it as the effect of mass curving the fabric of space and time. Large masses like stars and planets create dents or warps in spacetime, and objects move along these curves. The Einstein Field Equation $$ R_{\mu\nu} - \frac{1}{2}Rg_{\mu\nu} = \frac{8\pi G}{c^4}T_{\mu\nu} $$ mathematically expresses how matter and energy determine the curvature of spacetime. One of the most fascinating predictions of General Relativity is the black hole, a region where the curvature becomes so extreme that nothing, not even light, can escape. The boundary of this region is known as the event horizon, beyond which all paths lead inward toward a singularity, a point of infinite density. Read more
What If You Fall Into a Black Hole?
As you fall into a black hole, time slows down, space twists, and tidal forces stretch your body like spaghetti, it’s called spaghettification. Your feet experience stronger gravity than your head. If you're unlucky enough to fall in feet first, you'll be torn apart molecule by molecule.
Back holes aren't forever though. In 1974, Stephen Hawking stunned the world by suggesting that black holes emit radiation due to quantum effects near the event horizon. This glow is called Hawking Radiation, and it slowly drains the black hole's mass. Eventually, a black hole could evaporate entirely — disappearing in a final burst of energy.
This revelation gave black holes a new twist: they’re not just gravitational monsters. They're also thermodynamic systems, with entropy and temperature. Physics has never been the same.
In theory, black holes might be connected to wormholes or white holes. Are black holes doorways to other universes? Quantum physicists think it’s not impossible.
And in April 2019, we saw the Event Horizon Telescope captured the shadow of M87, a black hole 55 million light-years away.
Black holes aren’t just collapsed stars. They’re cosmic paradoxes, they erase information, yet emit radiation. Even crazier? At the singularity, both General and Special Relativity fail. We need a quantum theory of gravity.
But that's for another time.
See you soon.