If the galaxies in the Universe have been observed to be expanding ,how do we know that the Universe expands?.

Question

and why should it expand to go where?

Perhaps a different subtance different from the substance of space in the universe exists to contain the Universe at the curvature Einstein had described to be a finite one?

Answer 1

The known universe appears to be expanding. This does not mean it actually is expanding.

It might be gravity, or distortions in space affecting our perception of the universe.

It might be our misinterpretatons of the observations.

The observation is, that as we find galaxies farther away, they all are moving away, and the farther out they are, the faster they are moving away from us.

Does this mean the universe is expanding? Perhaps it means that the big bang occured at our location, thus everything is moving away from us. Yah, right....

Perhaps galaxies that were moving at high speeds towards us, have already passed us, and are now moving away from us.

Perhaps galaxies that are moving at high speeds towards us, have the electromagnetic energy from them shifted so much, that we cannot detect them by normal means. This might mean that there are the same amount of galaxies moving towards us as away from us.

Perhaps, the universe was expanding, but is now collapsing, but it takes 15-20 billion years for the light to reach us, and we can only see that they were moving away 15-20 billion years ago.

Lots of maybes.

Answer 2

By looking through that powerfull telescope you will notice that the last position of several different galaxies distance from the earth has increased with time exapmle. a galaxy viewed in the early 1900s will seem futher now thus explaining why the earth is expanding. it wount be because it is shrinking but galaxies allways expand constantly thus the smaller it is viewed today if it saw large in the early 1900s only means that it is further away from our galaxy than before. that is the only simple explanation i have for now. I dont know whats outside our universe.

Answer 3

I also have the same question in my mind and i am not getting the right answer from anyone...mine another question is: when it is true that universe is expanding whats the region that it occupies is called?
if you know the answer please mail me....