2
$\begingroup$

Just watched the 'How Big is the Universe?' TV program and it indicated that the universe is believed to be infinite in size. They used an approach involving measuring the internal angles of triangles. Or something like that anyway.

But hang on, the Universe has a known starting time and size followed by a finite time expanding at a finite speed. So surely, by definition, it cannot be infinite? I can accept it is honking big but by definition it cannot be infinite. Are they misleading me?

$\endgroup$

marked as duplicate by Rob Jeffries, user10851, John Rennie, Qmechanic Feb 22 '15 at 11:16

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

0
$\begingroup$

There is difference between what there is and what we observe. We do observe finite amount of matter and energy exactly because it all started somewhere and moves away, while speed of light is pretty constant. In that, most useful, sense universe is finite. We can speculate about size of what "there is", but it still will be baseless theories.

$\endgroup$

Not the answer you're looking for? Browse other questions tagged or ask your own question.