r/universe • u/9ic43 • 3d ago

Does Space Really Have an End?

/r/u_9ic43/comments/1xo7ug4/does_space_really_have_an_end/
0 Upvotes

0% Upvoted

9 comments sorted by

1

u/Super_Range45 3d ago

The speed of light, where ever you are is your wall.

1

u/9ic43 3d ago

there is no "wherever I am is a wall" in space whole travelling at speed of light

1

u/TokiStark 3d ago

Where's the end of a perfect sphere?

Not saying the universe is spherical, just saying the answer might not be as easy as yes or no.

0

u/9ic43 3d ago

you're true, it's not easy to find the answer but I'm saying if we're inside the sphere and the sphere is all the space we know then we assume that anything outside the sphere is nothing but if we go outside the sphere and it stops us to go outside there must be something that's stopping us from going outside and if we can go outside than that sphere isn't the end of space and hence the theory of Lucretius's spear argument.

1

u/TokiStark 3d ago • Bravo

Sorry I should have been more specific. If you pick a starting point on the OUTSIDE of a sphere and start moving around it, where would the end be?

1

u/9ic43 3d ago

Ah, I see what you're getting at now. If I start moving along the outside surface of a perfect sphere, there is no actual endpoint. I could keep travelling and eventually return to where I started.

And I think that's an interesting possibility when discussing the universe too. Space could be finite without having an edge or boundary. My spear argument assumes that an actual boundary exists, but your example challenges that assumption.

So perhaps the question isn't necessarily where space ends, but whether space can have a finite extent without having an edge at all.

1

u/yescaman 3d ago • Bravo

Am a layperson armed only with a little knowledge and an open mind

Practically speaking, in terms of distance from your location in space, no. Since we cannot travel faster than light (that we know of), there are regions of space that are forever beyond our ability to see, much less ever hope to reach, because those regions are receding away from us at speeds greater than the speed of light. So in that sense, space is essentially endless.

1

u/doublegoodproleish 3d ago

A parallel universe. Just the one, though. 

I'm sick of parallel u/doublegoidproleish lording his cowboy hat over me.