# A few interesting questions.

1. Dec 10, 2012

### Philosophy

I'm not studying physics or anything, i'm just working on a minor in theoretical astronomy for the fun of it on the side. I have a quick question i just wanted to have a few opinions on.

Suppose you take a handeful of marbles and toss them on the floor. Imagine that our universe is one of those marbles (not just observable, but theoretical entirety). Now imagine that other multiverse are the other marbles scattered around it. With the complete emptiness in space the distance between each.

Here are my questions:
1. If a new universe were to be born, let's say that each has a big bang unique to itself. Would the immense distance between each universe have any effect on the others?

2. Can gravity from an object be so great that light particles stop moving altogether (without being absorbed), remember i'm not a physics major so this may be a bad question.
but suppose that light is leaving an object with a gravitational force nearly equal to that of an event horizon but not quite.

3. going back to the multiverse scenario: How long would it take before the gravitational pull from a celestial force in Universe A affects objects in Universe B, if they have a distance at or near 1,000 gigaparsecs from each other.

4. To the above question: Is the speed of gravity proportional to the density or mass of the object? if there were a supermassive black hole infinitely larger than that of the largest we know of located in a seperate universe, then how long would it take before it affects us compared to a red supergiant an equal distance away?

5. Is a multiverse scenario even probable?

If anything is unclear, i will try to give a better explanation or ask in a more simplified manner.

these might be standard questions to you guys, or very stupid. They might be unanswerable i have no idea, that's why i came here. I am always asking questions about the universe. Most of my questions go unanswered but expect to hear more from me as i continue to learn. As stated, my focus is not in physics, i'm terrible at math, that's why i stuck to theoretical, since i'm useless as an astrophysicist.

2. Dec 10, 2012

### sophiecentaur

Hi there.
You have hit us with a load of questions all at once. You stand a better chance of getting answers and opinions if you split them into one question at a time.

Comment on Q1. : What would you mean by 'distance' in this context? All the 'distances' that we consider are within this particular Universe. Other Universes would exist outside the one we know (in some way). It's not like just finding another galaxy a long way away in this Universe.

3. Dec 10, 2012

### Staff: Mentor

As purely mathematical solution of GR: If you emit a photon "exactly" at the event horizon in the right direction, it will stay there. You could consider that as "stopping", but it depends on your arbitrary choice of coordinates (!). Any deviation from that "exactly" will lead to the photon falling into the black hole, or leaving it.

You need space to define a distance, and if two objects have space in between, I would consider them as in the same universe. Note that you cannot have a big bang "in" space.

No, deviations in mass distribution always propagate with the speed of light.

There is no "infinitely larger", but the time depends on distance alone.

There are many possible multiverse scenarios.