RichA wrote:
On Tuesday, 1 January 2019 09:54:16 UTC-5, Chris L Peterson wrote:
On Tue, 1 Jan 2019 00:19:24 -0800 (PST), RichA
wrote:
No, we are on the surface. The surface is "now". The center is t=0
(actually, it is (0,0,0,0), the location of the Big Bang). The past
is inside the sphere, where it is not accessible to us.

IBTD.

If we are to take this literally, then the universe isn't flat, it
has no end-point (for us) and building bigger telescopes means
little.
I don't follow. Why is there no value in building instruments that
extend how far we can see, in both space and time?

Stupidly, I was actually hoping that they could build scopes large enough
to see the brightest objects at the edge of the known universe.

This has never been possible because we can only see (into) the past.
Therefore, the farthest thing that we can actually *see*
(electromagnetically) is the last scattering surface (LSS), before our
universe became transparent:

https://en.wikipedia.org/wiki/Cosmic_microwave_background

Gravitational waves provide a new way of seeing, but they can only
take us further back in time, to the Big Bang event (and maybe beyond).

Unfortunately, if we are on a sphere, there is no edge, we'll see to a
certain distance and that'll be it.

Even worse, we simply cannot see our universe at this distance as it is now.

https://arxiv.org/abs/astro-ph/0310808

Building larger scopes now will enhance what we can see however.

Yes.

However, I'm not even sure I buy the sphere idea anyway.

This is not a new idea. The idea that is rather new is that dark energy
makes it possible for the surface of our universe to be a sphere without
its eventually collapsing.

However, the current standard model suggests that our universe should be
flat, and observations confirm that; so I wonder how the Upsala researchers
reconcile their model with the observations of e.g., the Planck Collaboration’s.

This has nothing to do with *amateur* astronomy. F’up2 sci.astro.

--
PointedEars

Twitter: @PointedEars2
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