In article , Gary
Harnagel writes:

The "arguments" from the "other side" are taken as FACT:

https://www.space.com/52-the-expandi...-big-bang-to-=
today.html

space.com is hardly the best place to see what scientists really
believe.

"The universe was born with the Big Bang as an unimaginably hot, dens=
e
point. When the universe was just 10-34 of a second or so old -- tha=
t
is, a hundredth of a billionth of a trillionth of a trillionth of a
second in age -- it experienced an incredible burst of expansion know=
n
as inflation, in which space itself expanded faster than the speed of
light."

Yes, this is the standard idea.

Which came from space.com, so I don't understand your snide comment.

space.com is basically an internet newspaper. Some things they write
are formally correct, some are not. At best, you could argue that
space.com takes the standard scenario as "fact" instead of "hypothesis".

It's hard to propose experiments for something SO big. What Steinhardt
needs are some little predictions, though.

Indeed.

As for Lemaitre, he had a hypothesis
which went beyond what was known at the time; it was not a rival to=

another hypothesis attempting to explain the same thing.

So he was a smart guy and found a way to propose a theory consistent =
with
both GR and his religion.

Yes, Lema=EEtre was a priest, but the idea that he favoured the big ban=
g
since it is consistent with his theology goes against all we know about=

him.

You think his belief system had NOTHING to do with it? Each of us has ou=
r
own model of the universe that we have developed over our lives. I have
mine and you have yours ... and Lemaitre had his.

Yes, he was a priest, but, unlike some other scientists who are
Christian (i.e., Christian scientists, not necessarily Christian
Scientists), such as Don Page, he managed to keep the two areas
separate. The Big Bang really has little to do with the biblical
creation story, apart from the fact that in both the universe is not
infinitely old. This is a superficial similarity.

Sure, but not so dense that collapse is inevitable. And it doesn't
matter that quantum effects "may" prevent a singularity. It's unlike=
ly
that they can be responsible for an expansion.

Who said that they are?

I think we'll have to look outside our universe for the that, but it COUL=
D
be quantum effects (brane theory is a quantum theory).

I meant "Who said that they are responsible for expansion?"

It seems to me that expansion is possible only if the initial size/ma=
ss
is great enough (i.e., greater than the Schwarzschild radius.

The Schwarzschild radius is not applicable here; it is applicable in
static asymptotically flat space-times.

It seems to be quite close to that now. Why propose that it was differen=
t
in a past that we can't detect?

Because the Schwarzschild radius, as I already mentioned, applies in an
asymptotically flat spacetime. That does not describe the universe.

Note that a mass with density only that of water and with a radius ou=
t
to the asteroid belt would form a black hole from which nothing could
escape.

There are various estimates for the mass of the universe:

http://hypertextbook.com/facts/2006/...cPherson.shtml

varying from 1e50 to 1e60 kg (I'm ignoring the entry that proposes
infinity).
For the mass range indicated, the Schw. radius varies from 16000 to 1=
60
trillion light-years, it being 1.6 billion light-years for M = 1e55=
kg.

Don't be confused by dimensional analysis;

That's NOT "dimensional analysis." You might repeat your claim that the
Schwarzschild model doesn't apply.

The mass and radius of a spatially closed universe correspond to those
of a black hole, basically because of "dimensional analysis", not
because the universe is a black hole.

the universe is not a black hole, even if it is dense enough.

How do you know this?

Maybe the moderator can insert some standard text here. Basically, a
black hole is a region WITHIN space(time).

[[Mod. note -- Ok. This is basically a question of what we mean by
the phrase "black hole". The standard definition is that it's a region
from which light rays can't escape to "far away" (from the black hole
region). Among other things, this definition relies on their being a
set of events (points in spacetime) that we're willing to call "far away"
(from the black hole(s)).

But there's no meaningful way to say that some points in spacetime are
"far away" from the entire universe. So, there's no meaningful way to
even ask the question "is the universe a black hole".
-- jt]]

Indeed. There are quantum gravity theories that equate to GR in the weak
field. String theory is one of them.

Also a problem of a lack of testable predictions.