Black hole question?

Question

If time appears to go slower as an object gets nearer the event horizon, how can black holes increase it size.

Answer 1

You have to take into consideration the different observation frames.

For an *outside* observer looking at something falling in, the time for the falling object seems to slow down and the outside observer will never get any information past the point where the falling object crosses the event horizon.

HOWEVER, from the point of view of the falling object, it crosses the event horizon in a finite amount of time and then continues to the singularity where it gets shredded. Time does not stop from the point of view of the falling object, only from the point of view of the outside observer *looking* at the falling object.

From the view of the outside observer, the mass of the falling object is added to that of the black hole simply because they are forever close together.

Answer 2

Black holes are the evolutionary endpoints of stars at least 10 to 15 times as massive as the Sun. If a star that massive or larger undergoes a supernova explosion, it may leave behind a fairly massive burned out stellar remnant. With no outward forces to oppose gravitational forces, the remnant will collapse in on itself. The star eventually collapses to the point of zero volume and infinite density, creating what is known as a " singularity ". As the density increases, the path of light rays emitted from the star are bent and eventually wrapped irrevocably around the star. Any emitted photons are trapped into an orbit by the intense gravitational field; they will never leave it. Because no light escapes after the star reaches this infinite density, it is called a black hole.

Answer 3

Subjective time, (for the in-falling object),  stands still at the event horizon.

Objective time, (for the rest of us), goes on.

Answer 4

Black holes are greedy. They swallow everything.

Time only stands still on the edge of a black hole

Answer 5

Objects don't slow down from our outside perspective so an object will accelerate to near the speed of light and then enter the even horizon just like expected. A person falling into the black hole would perceive more time to pass than we do. Instead of an outsider measuring 10 hours going by the person might measure 5 hours before they get torn apart.  

Answer 6

all i can say i know about black holes is that stuff is not 'sucked' into it, it falls like a penny in those huge circle things at malls. eventually it gets to a point that light is not quick enough to escape. your event horizon i suppose. i don't think it has anything to do with time. because space is time. dang now you've got me all confused, my professor explained it so well i just can't remember.  

Answer 7

The more matter and energy a black hole swallows, the larger and more massive it becomes. There is no limit to how massive a black hole can be other than how much matter and energy nearby for it to feed upon.

Answer 8

A black hole is a singularity, meaning it literally has no size. However, as material falls into it, it will gain in mass. Remember that as we watch material cross the event horizon, time appears to go slower, based on our vantage point. If you were falling into a black hole, this would not be the case.

Answer 9

Excellent question.  IDK the answer, further, the people who are answering either do not understand the question or are incapable of answering it.  I often see this on Yahoo Answers to more original questions.

For an external observer the time taken by an object to fall to the event horizon is infinite.

How then can the mass of the black hole increase prior to t=∞ ?

And:  When does the mass (surface area) of the black hole change?

The falling object's reference frame is irrelevant to this question and the answer.

Answer 10

Have you never seen inside a Tardis?

Answer 11

The keyword is "appears". The apparent flow of time on a spaceship approaching the event horizon will only seem to slow down for an external observer! For the unfortunate guy inside the spaceship, time will run at the same speed untill his end in the singularity.

What we will observe from an external point of view is the spaceship dissapearing at the event horizon (due to the ever increasing red-shift making in invisible), but the black hole will grow in size!

Answer 12

that's the whole thing black holes are bogglingly confusing and they are supposed to be

the question what you are asking can be answered if we ever understand what exactly dark matter is then it can be answered but till then its a mystery