What happens when you fall into a black hole?
An explainer for non-physics people.
As a high school physics teacher, I often get asked some obscure and loaded questions when connecting with old friends or new people for the first time. “What would happen to you if you fell into a Black Hole?” “What would happen if you stuck your hand in the path of the Large Hadron Collider?” “So what do you think about the Higgs Boson, what’s the big deal about it anyways?”
You know, just your basic questions with complex answers, if there are even known answers to begin with. But alas, I’ll attempt one.
So, what would happen if you fell into a Black Hole?
First off, what is a Black Hole?
Once a very large star uses up all its fuel to burn, it will explode (supernovae) and contract like a whip, with the latter phase packing a lot of stuff (matter) into a very, very small space. The final product is an object that is very, very dense (lots of matter in a small amount of space), a black hole. Because it is massive and small (has lots of “stuff”) at the same time, it has some of the strongest gravitational fields ever seen in our universe.
A black hole’s gravitational pull is so strong that even photons (particles of light), the fastest known massless particles in our universe, can’t escape them. Since photons traveling at light-speed become trapped and ‘fall in,’ these mysterious objects have the name “black” hole. Every black hole has what is called an event horizon, which is a sphere marker surrounding it that’s considered the point of no return.
Once you cross that event horizon, not even light will be able to escape the ever-increasing gravitational pull.
Black holes are not as uncommon as you’d think. Our own Milky Way galaxy has a super massive black hole at the center that our solar system orbits around. Luckily for us, it’s very far away and we’re in orbit around it. Even though we are technically falling towards it, we happen to be moving so fast horizontally that the event horizon curves before we would cross it, just like a satellite orbiting the Earth in Newton’s cannon.
Falling In
If you fell straight into a black hole, you’d die. Period. That may sound anti-climatic, but interestingly enought there’s a lot more that would happen. If by some hypothetical miracle you were able to survive the strong gravitational forces at your feet or head (whichever way you dived into the black hole), lots of cool things would happen.
First of all, you would “spagettify.”
The gravitational forces at your feet would be significantly larger than the forces at your head as you moved closer and closer, and your body would stretch out until you resembled a spaghetti version of your former self.
In addition, you would apear as a frozen image in time at the event horizon to all your friends and family lucky enough not to fall in. The light coming from your body would be stuck trying to swim up a stream of space-time that is flowing down at a matching speed. This is very much like a swimmer or fish trying to swim upstream in a river of flowing water but stuck in the same place.
Lastly, you would see time move faster. Looking back at the rest of the universe (your friends, your dog, your planet), the rate at which time passes would get faster and faster. Right at the strongest parts of the gravitational fields, seconds on your wrist watch could become billions of years for the rest of the universe if you look back. Mathematically, as that gravitational field strength approaches infinity, the rest of the universe would approach infinite time (whatever the heck that is). Very meta and very much like Interstellar.
Alternate Theories
Gravity can be thought of as a “bend” in space-time, where planets and stars warp the space-time around them and objects like photons just travel along these warped paths. This model can be thought of like trampoline mesh, and placing heavy objects on a trampoline to bend and stretch the mesh.
With this model, the stronger gravitational pull would create a larger warp in space-time, thus affecting passing photons and other objects a lot more. A black hole is theorized to warp space-time so significanly that it’s stretches this space-time trampoline mesh down to a point called the singularity.
Black Holes are constantly absorbing light and energy from our universe, which somewhat violates the idea of energy never being created or destroyed (Conservation of Energy Principle). Some physicists believe that, to preserve the Conversation of Energy concept, Black Holes could be wormholes to other universes where the opposite happens. “White” Holes, objects that spew out light and energy could be connected to the Black Holes in our universe and exist in another universe.
As cool as that sounds, it’s probably not a viable theory until we find evidence for a White Hole within our own universe.
But remember, as cool as it would be to maybe traverse from our universe to another and emerge from a White Hole, you will die if you fall into a black hole. Not recommended, and I’d definitely avoid them, if possible, next time you’re traversing the cosmos.
If you’re reading this and have your own thoughts and experiences to share about black holes and best practices to avoid them, please share in the comment section!
Caught the teaching bug? Check out this article to gain insights on the life of a teacher:
