Because that is the prevalent scientific opinion

We are on a course for a confluence of some major technologies this century which could result in another great leap forward.

Anyways i forgot why i dont bother to reply much on this site, got down voted for my above comment yet no indication as to why (is it my comment about working on advertising? its ok that's what I work in too myself have to pay bills somehow, but would rather do something more interesting).

The observable universe is very much finite. (And if speed of light is a barrier, than the observable universe is about the biggest thing we can ever influence.)

Sure, there will be lots of nice technology coming over the next century. No doubts about that.

Lets assume we develop technology to travel at near light speeds and go mad colonising the universe, what exactly contains us to the observable universe, move 4 light years in another direction and your observable horizon shifts

Except the expansion is happening faster than the speed of light.

http://curious.astro.cornell.edu/about-us/104-the-universe/c...