# Take a Fun Trip into a Black Hole: What's It Like Inside?

#### rod

Good video. I am looking forward to next week discussion. How many primordial black holes were created in the universe during the Big Bang event? My understanding, when you fall through the event horizon of a black hole, time slows down for you and you may never reach the singularity at the bottom. From your black hole frame of reference - time is running differently in the universe so the universe - evolves rapidly. I hear when you fall through the event horizon - you may never fall to the bottom of the black hole because of time dilation

#### gproietti

A question : While you are approaching to the event orizon your time dilatates asintotically to infinite, so for an external observer looks you will never reach the orizon because you will need an infinite time to touch it.
Reversely, you, falling towards the orizon will see the universe time accellerating till infinite while touching the orizon.
How this can match the statement in the article where is said you will see rest of the universe accellerating once you are inside the orizon ?
Universe should appear having already reached the "end of the time" (whatever sense this definition could mean) while you where crossing the Orizon.

#### Dwight Huth

BANNED
Im going to have to say that the center of a black hole is round.

Take the horizon of Earth right when light and darkness meet. We can see the event horizon of the black hole much the same that we can see the horizon of Earth.

We know that the horizon of the Earth is not flat but if we continue to approach the horizon of a black hole we know that it wraps around to the point that we started at.

Otherwise the Event Horizon of a black hole would consume all of known space the moment it's star became a black hole.

#### AlisterG

when you fall through the event horizon of a black hole, time slows down for you
Not quite, for you, time will appear to tick away at the same rate, while you will perceive things outside the event horizon to be sped up.

#### AlisterG

Im going to have to say that the center of a black hole is round.

Take the horizon of Earth right when light and darkness meet. We can see the event horizon of the black hole much the same that we can see the horizon of Earth.
The event horizon is indeed spherical, but what lies at the centre is a mystery. Since quantum mechanics, and the introduction of the Planck length, the classical picture of an infinitely dense singularity has fallen somewhat from the realm of physics to simple mathematical terminology. A range of new ideas such as
spin foam networks and loop quantum gravity try to describe what a black hole may be.

As for seeing the event horizon, this won't occur unless there is a light source (which could be an accretion disk of glowing plasma) behind the black hole. One could encounter a big black hole and simply not see its event horizon (Hawking radiation is too faint), but that wouldn't make for a good Hollywood visual.