Does space go on forever?

In a constantly expanding universe there might be the outer edge but not an end. In that theory it will apparently begin collapsing and that should be fun . . .

Yet, in a steady-state theory I suppose there is an end which might tie in to the flat earth belief and we'll just fall off the edge . . . :rolleyes:
 

Nathan, mentioned that it's so hard to comprehend that something has no end, and that's me.

I have tried and tried to envision the end, an end, and yet the more I gaze into the sky, particularly at night, where an infinite number of stars and planets abound, it's so prodigious to think that the possibility exists where space continues forever.
 
Good question, both for a scientific as well as philosophical.

Our minds can't comprehend something that has no limits. I think somewhere in the Old Testament(in Genesis) there is some wording suggesting that the universe("the world") has no beginning or ending.
Genesis 1.1
The Creation
1In the beginning God created the heavens and the earth.

Space would have to have an end if using the bible as a reference is to be believed.

To create the heavens and the earth
cre·ate
verb
bring (something) into existence.

God would have to be outside what is created. Which brings up the question where would that be?
 
Do you believe the universe has an end?

In other words... does the universe have an edge? A wall? An end?
Some of us who're schooled in math and science have no problem with the concept of infinity and the extents of the universe being such. Others are more comfortable with the idea of distinct boundaries, as that's all we've known - crib/playpen, room, house, yard, town, county state, country, continent, earth, galaxy, etc.. Both views are fine until one or the other is proven, which I don't see happening. Personally, I think the universe is infinite, as might be the nature of reality (e.g., How many distinct frequencies are there in the electromagnetic spectrum?).
 
I envision it kind of like the infinity sign. There's no beginning and no end, just goes around and around.

The idea that the universe has an edge or wall makes me think of that movie The Truman Show, where Jim Carrey was sailing and hit the end of the ocean...a brick wall. :eek:
Reminds me of a flying video game I used to play. Got interested in how far off the map it would allow me to wander. Took some time but I finally hit the edge. Turned around and headed back curiosity satisfied. Didn't win any points for that excursion . . . :rolleyes:
 
I envision it kind of like the infinity sign. There's no beginning and no end, just goes around and around.

The idea that the universe has an edge or wall makes me think of that movie The Truman Show, where Jim Carrey was sailing and hit the end of the ocean...a brick wall. :eek:
And although it’s obviously funny, there ARE people who actually think this way.😱
 



Local Curvature of Space​

According to Einstein’s theory of general relativity, massive objects warp the spacetime around them, and the effect a warp has on objects is what we call gravity. So, locally, spacetime is curved around every object with mass.

Overall Curvature of Space​

Closed universe (top), open universe (middle), and flat universe (bottom).  NASAClosed universe (top), open universe (middle), and flat universe (bottom).
NASA
Mass also has an effect on the overall geometry of the universe. The density of matter and energy in the universe determines whether the universe is open, closed, or flat. If the density is equal to the critical density, then the universe has zero curvature; it is flat. You can imagine a flat universe like a sheet of paper that extends infinitely in all directions. A universe with density greater than the critical density has positive curvature, creating a closed universe that can be imagined like the surface of a sphere. And if the universe’s density is less than the critical density, then the universe is open and has negative curvature, like the surface of a saddle.
Measurements from the Wilkinson Microwave Anisotropy Probe (WMAP) have shown the observable universe to have a density very close to the critical density (within a 0.4% margin of error). Of course, the observable universe may be many orders of magnitude smaller than the whole universe. But the part of the universe we can observe appears to be fairly flat.
 
How do we know that the universe is infinite?
Shutterstock

Is the Universe infinite or do we say that because we have not travelled to, or seen it's walls, yet? Originally appeared on Quora: the place to gain and share knowledge, empowering people to learn from others and better understand the world.

According to Viktor Toth, an IT professional and physicist:

The simplest cosmology that fits the large-scale characteristics of the universe is the so-called Friedmann, Lemaître, Robertson, Walker cosmology describing a spacetime that is homogeneous (same everywhere) and isotropic (has no preferred direction). This simple cosmology is characterised, among other things, by a variable that represents spatial curvature. It can be positive, negative, or zero.
Our best observations to date strongly suggest that the universe has no spatial curvature. It may be expanding in time, but the geometry of space, at any given time, is Euclidean. (Euclidean geometry is a mathematical system attributed to Alexandrian Greek mathematician Euclid, which he described in his textbook on geometry: the Elements. Euclid's method consists in assuming a small set of intuitively appealing axioms, and deducing many other propositions from these.)

The simplest topology that corresponds to Euclidean geometry is that of flat, infinite space. So by Occam’s razor, i.e., the parsimony of assumptions, we can conclude that in the absence of evidence to the contrary, the universe appears infinite.
That does not mean that we know this for sure. In fact, there really is no way of knowing. What is beyond the limits of the observable universe is, well, not observable, not even in principle. So for all we know, just outside the observable universe there is a big bad wall. Or a brane-type singularity. Or fire-breathing pink unicorns preventing us from going any further. Nature is under no obligation, after all, to behave in a manner that we humans call reasonable.

But in our experience, nature by and large does behave reasonably, and we might expect it to continue behaving reasonably even beyond the boundaries of the observable universe. That expectation, combined with the observation that the universe appears to lack spatial curvature, leads to the concept of a spatially infinite universe.

I like the idea of fire-breathing pink unicorns.
 
Do you believe the universe has an end?

In other words... does the universe have an edge? A wall? An end?

Wall, as in a name, the Great Sloan Wall, over a billion light years in diameter. Others exists. But such do not indicate the end of Space, in theory, there is none, in reality, there is none also, my opinion.
 
This question cannot be answered with the application of math or measuring tapes for many reasons. Most obvious is our physics as we know them don't apply. The universe is constantly expanding and the more it expands the faster it expands. This created the term "dark energy". The theory called the M Theory is used to try to grasp a definition of what the universe is and does suggest there is more than one and they were created out of nothing. So, how big is the universe? It is.
 
We don't know, but many theories abound.
Coming late to this discussion I apologise if this idea has already been raised.

Some think that space may curved and fold back on itself.
It could be represented by dots on an inflated balloon ???

Me? I don't worry about the cosmos because my brain is too limited to take it all in.
 

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