It's the red shift.

There are 2 models for light: particles and wave. Both are equal and correct.

Because room is expending, the wave length increase. Depending how much it increase we can calculate how long it's needed and can calculate the different distances with this information.

(It's like the Doppler effect with sound)

It's matter outside from the accretion disk, so the incoming mass.

I don't know the fully theory behind it, but it heat ups so massive, that it's going to the poles of the black hole and send out as a jet.

You mixed up things.

Quasars don't blow stuff from inside the black hole, it's still part of matter from outside of the black holes.

Yes.

And you know the 2. Law of thermodynamics. So atoms will lose their energy and disintegrate after some times.

It depends, and currently we can't measure it with enough accuracy.

Most of the scientists thinks a big chill will happen (the universe will be more could from time to time).

I read more, it could be, when the temperature is more next to 0K also atoms will disintegrate into photons and electrons.

No, the distance between objects in stellar will be smaller. The expansion or the opposite doesn't matters a lot for us.

Currently the room between all objects increase, also between sun and earth. But the gravity can easily hold it together.

>Time is still a vector which is ongoing, where the room will be smaller from time to time.

In addition to this. The universe could be still infinite, but it's smaller then before ;)

From what i know, this will not happen.

Time is still a vector which is ongoing, where the room will be smaller from time to time.

Then gravity force objects into each others and the energy density increase, so the universe will heat up.

At a certain point it's so hot, matter don't exist and it falls into its subparticels.

In addition to B)

You can still have planet, dead suns and other stellar objects in a galaxy, as long it has a stable orbit.

But like other mentioned, hawking radiation is a topic. When background radiation will be smaller then hawking radiation from a big black holes, it loses energy = mass. Because it loses mass, the orbit from all objects around will increase. So in a long long long future it could be, that galaxies disband and only some single solar systems with dead suns exists...

There are 2 possible options.

a. The expansion of the universe reverse at a certain point

B. It will expand for ever

A. In this case, the universe fall back into a new singularity.

B. The universe will be more and more cold and the distances between objects increase and the black holes and dust stay for itself. (So galaxies, maybe cold still exist as more and more single objects, because the gravity can't hold more objects together)

They don't travel faster then light. The room between expend.

It's like you stretch slowly a rubber band. The distance between ends of the band increase faster then somewhere in the middle.

The expansion of the universe don't interfere SRT or ART. Lightspeed is still lightspeed, but when expansion is bigger then 300k km/s, the light can't brigde over the whole way.

>When the light left galaxies, they were 14 billion light years away but now they are 90 billion light years away.

That's not true, also the space between light and goal expend.

The current star with the most distance exists 900000000 years after bigbang and is now 12,9 billion light years away. But when the photon was send out, it was 1,75 billion light years away. The light needs 13 billion years to travel to our position. (Z = 6,2)

>I know as a fact that the expansion of space is faster than the speed of light. But how do we know that?

That's not fully true. The expansion of the universe scales up with distance.

Current measurement of hubble constant is 68 - 74 km/s/Mpc.

That means, a object in a distance of 1Mpc "move away" by 68-74 km/s. ==> For objects next to us it's less, for objects far away it's more.

Next, there is a event horizon, when the distance is so large, that the expansion is larger in distance per seconds then 300000km/s (light speed). For Objects behind this event horizon, light can't go to earth and we don't get any new information.

For your second question and why is the (visible) universe 93 billion lightyears in diameter and just 14 billion years old.

Same reason, in the beginning the (visible) universe was much smaller. An object send out photons. This photons "travel" in our direction. Because the universe expand, the way between object and our location increase. When the light is measured on earth, the object is much more far away, when the photon was send out.

>That's what scary; that we may have made some big mistakes in our theory of the early universe.

I don't think it's scary, that's the simple development from theories in science.

More, if you find inaccuracies in your models, you can develop it.

A famous example are the relativity in classic systems by Galileo and the axioms from newton which are developed to SRT/ART. And i don't think this is the end.

Edith says: so, i'm every time happy, when big theories are false in some kinds, so you can improve it or find new theories.