@Fil Albuquerque,
What does energy and matter being convertible mean for what I said?
Do you want a specific number or are you making a point?
If you're making a point, please clarify it.
I assume you're asking why would it not be possible to 'traverse infinity'
And the reason for that is a philosophical one as well as a scientific one.
First, since you have not told me that the GTR is invalid or irrelevant, I am going to assume that it's still in play. If it's still in play that means the universe has a beginning and is therefore not infinite.
In order for today to be here in an infinite system, we would have to start at infinity ago. Once we've waited an infinite amount of time, we would finally reach today. Unfortunately, infinity is not finite, as it is infinity. Because of that, there is logically no way to cross an infinite space, wait an infinite amount of time, or go from the start of infinity to the end of infinity in any way except theoretical. And that means that there could not have been an infinite amount of time before today.
Also, time cannot be infinite, as it has an end, now. The present moment is the end of all real time. When I say real time I mean time that exists. Everything in the future is only theoretical as the only way to prove it exists is to 'give it more time' until it becomes the present.
If I tell you "prove to me the future exists."
then the only thing we can do is wait for the future to become the present to find out if it does or not. But once we reach the future, it is the present and therefore the future is both tantalizingly out of reach and purely theoretical.
Because of this, time has an end and is therefore bound by a limitation. That - by definition - makes it not infinite.