How do we know the universe will continuously expand and never contract?

Question

How do we know the universe will continuously expand and never contract?

In: 2

Answer 1

We’re only reasonably sure.
There were and still are some scientist looking into the idea that the universe’s expansion would slow, stop, then reverse, eventually collapsing back into a point in an event called “The Big Crunch”.
There are a lot less of these scientists then there were 20-30 years ago.

The reason as we got better telescopes we were able to see farther.
When you farther, because light takes time to move, you see further back in time.
The further back in time we see, the slower the expansion of the universe seems to be.
Meaning expansion seems to be speeding up.
There are enough error bars on the whole thing that some rational scientist aren’t convinced though.