GR and cosmology (split from …A Shrinking matter theory that might actually work.)

[bangstrom]

2 hours ago, beecee said:

The redshift of light (lengthening) is said to be caused by the expansion of spacetime.

 

The expansion of spacetime is an assumption… not an observation. Perhaps, the universe has always been the enormous size that we see today while all the material within has been uniformly shrinking in size. With either scenario the observations are identical. They are just the same scenario viewed from different perspectives.

Russel Ryerson described the two views as one being the simple mathematical inverse of the other. He called one view “expansion” and the other “inverse-expansion.”

Arthur Eddington said of his “shrinking atom” theory that a universe of contracting matter is the conceptual and mathematical equivalent of an expanding universe. We don’t have an external god’s eye view of the universe to say from the great beyond whether the universe is expanding or whether all material within is growing smaller. The observations from our inside view should be identical in either case.

2 hours ago, beecee said:

If we use the shrinking rule perspective, how does that fit in then with the gradual diminishing of the CMBR?

Again, the diminishing of the CMBR is an assumption… not an observation. The world we see now is the CMBR in its present non-diminished form. We are what became of it. If some bug eyed monster form the the other end of our geodesics could view our corner of the universe, we would be their CMBR.

 

2 hours ago, beecee said:

how does that fit in then with the gradual diminishing of the CMBR?

 

 

 

2 hours ago, beecee said:

The temperature was around 3000K when the first element formed.

Again the 3000K is an assumption… not an observation. The observation is that the temperature of the CMBR is 3.73K and there is nowhere to go from there but up.

In a shrinking ruler theory, the universe remains the same enormous size but the rate of time in the early universe was extremely slow and it was crammed with H atoms, perhaps as large as baseballs, that emitted light in wavelengths proportional to their size which is why we see primal light sources as redshifted. And the atoms had a temperature of 3.7K.

Extreme temperatures and confinement are necessary for fusion to take place, but if temperature is lacking, confinement will suffice so the shrinking ruler model does not exclude the possibility of fusion in the early universe.

As the universe aged, atoms grew smaller, and like the ice skater who spins faster when she withdraws her arms, we see atoms spinning and moving faster which we observe as a quickening of time and a rise in temperature.

 

2 hours ago, beecee said:

Plus there is obviously a limit to how much anything can shrink.

The Plank scale puts a limit to contraction, in which case, the universe may fade into a quantum uncertainity possibly to survive to repeat the cycle.

Edited February 28, 2022 by bangstrom
duplicate

[beecee]

6 hours ago, bangstrom said:

The expansion of spacetime is an assumption…

 

Again the 3000K is an assumption… not an observation. The observation is that the temperature of the CMBR is 3.73K and there is nowhere to go from there but up.

 

The Plank scale puts a limit to contraction, in which case, the universe may fade into a quantum uncertainity possibly to survive to repeat the cycle.

The expansion of spacetime is based on the cosmological redshift of light. This expansion is observed over large scales, while over smaller local scales, gravity decouples us from that expansion. Seems OK to me and not sure how one can fit shrinking rullers into the fact that gravity decouples the expansion over local scales.

How can you say the 3000K is an assumption? We know enough physics to be able to ascertain when electrons can couple with atomic nuclei.

The Planck scale puts a limit on contraction, sure, and then you go and promote your own speculation? The expansion has no such worry.

You then go on and make many other assumptions. 

6 hours ago, bangstrom said:

Again the 3000K is an assumption… not an observation. The observation is that the temperature of the CMBR is 3.73K and there is nowhere to go from there but up.

It's 2.73K actually and the only way to go as expansion continues and accelerates, is down in actual fact. We have a cosmological model with each part fitting snugly into the other parts, and even if Russel Ryerson is correct in  describing the two views as one being the simple mathematical inverse of the other, one certainly (expansion) appears far more likely and makes infinitely more sense.

[bangstrom]

8 hours ago, beecee said:

The expansion of spacetime is based on the cosmological redshift of light

True, but expansion is not the only explanation for redshifting. Besides redshifting, what observations support expansion?

8 hours ago, beecee said:

How can you say the 3000K is an assumption? We know enough physics to be able to ascertain when electrons can couple with atomic nuclei.

 

 

8 hours ago, beecee said:

How can you say the 3000K is an assumption? We know enough physics to be able to ascertain when electrons can couple with atomic nuclei.

 

3000K is an assumption because it is a theoretical calculation and not a direct observation. It may be explainable but it is still an assumption based on another assumption that galactic redshifts necessarily indicate expansion.

8 hours ago, beecee said:

This expansion is observed over large scales, while over smaller local scales, gravity decouples us from that expansion.

 Firstly, redshifting- not expansion- is what we actually observe over large scales.

The galaxies are gravitationally bound but they exist within a far greater gravitationally bound object which is the universe itself so how does gravity prevent galaxies from expanding while allowing the universe to expand?

Mach’s principle applies when thinking of gravitational effects globally. Mach explained that the vastly overwhelming gravitational effect on local environments comes from the combined gravity of all the massive bodies in the universe.

Mach illustrated the universal effect of gravity with his example of a spinning gyroscope. A gyroscope orients with the gravity of sidereal space and is not noticeably affected by local gravitational effects such as the Earth or the sun. We normally ignore gravitational effect from the total mass of the universe because it is equal from all directions so we only consider the small local variations as “gravity” but gravity is a scalar value that exists everywhere and effects everything much like air pressure.

If the gravitational binding of galaxies explains the decoupling from expansion, then I would expect an observable variation in the properties of matter between large galaxies and small galaxies and even more variation for the matter found in extragalactic space. The uniformity of matter calls for a more global explanation than the gravitational binding of galaxies.

I consider this more global explanation is, as Mach explained, the combined gravitational effect of from all massive bodies in the universe. This comprises the spacetime environment that dictates our observations of distance and time and the physical properties of matter itself.

I suspect this more global explanation is what caracol calls his “equality principle.” Wetterich calls it the “cosmon” and I call it by the old name of Mach’s principle but I find this to be different words for the same thing.

8 hours ago, beecee said:

The Planck scale puts a limit on contraction, sure, and then you go and promote your own speculation? The expansion has no such worry.

 

Eternal expansion has other worries such as a Cold Death to the universe and the universe being a one time event. The two views have different eschatologies.

8 hours ago, beecee said:

even if Russel Ryerson is correct in  describing the two views as one being the simple mathematical inverse of the other, one certainly (expansion) appears far more likely and makes infinitely more sense.

If the universe is expanding radially relative to the atomic scale, then the atomic scale is necessarily growing smaller relative to the radius of the universe. The two possibilities are mutually inclusive and one can’t be any more likely than the other.

Astronomers were once fond of popularizing expansion theory by saying it implies that the entire universe was once no larger than a golf ball. This assumes that we can step outside our universe and watch it expand from golf ball size to the present. Also, everything in the universe crammed into the volume of a golf ball is not easy to visualize.

The only way we can observe the universe is from the inside and this is what caracal’s model attempts to do so it is one step closer to reality than the alternative. Expansion theory is only more difficult to visualize because it is more familiar to think of the scale of the universe from the outside than from the inside. But an inside view is our only real alternative.

The advantage of having two models instead of just one is that we can look at the same phenomena from more than one point of view and this gives us perspective. If our interpretation of of both models does not coincide, we know there is a discrepancy somewhere to be resolved.

If expansion theory conformed to observations there would be no need for considering other models but the problem is it doesn’t which is why we have ad hoc patches as Guth’s inflation and dark energy and why we determine the size of the universe using redshift values as indicators of recessional velocities even though we know they are not recessional.

 

Edited March 1, 2022 by bangstrom

[Genady]

55 minutes ago, bangstrom said:

The galaxies are gravitationally bound but they exist within a far greater gravitationally bound object which is the universe itself so how does gravity prevent galaxies from expanding while allowing the universe to expand?

GR equations - not words - show how it happens.

[bangstrom]

3 hours ago, Markus Hanke said:

20 hours ago, bangstrom said:

If time quickens, lengths grow shorter so locally length and time remain proportional to the value of c.

Since all changes in distance and time remain proportional to c there is no change in proportions that requires rescaling.

That makes no sense - if there’s no rescaling of size, there is no shrinking matter. You can’t have it both ways.

No one is saying atoms can’t change in size. I am saying atoms can change in size without changing their proportions so there is no change in proportions that require a rescaling. In other words, atoms today are small scale models of atoms in the distant past just as the in the BBT where space itself is a large scale model of what it was in the past.

3 hours ago, Markus Hanke said:

20 hours ago, bangstrom said:

How do you know if light has lengthened or if your standard for length has grown shorter?

One is physically possible, the other one isn’t.

In the expansion model, what was the distance of a light year when the universe had a radius of one half a light year. Which one is impossible to change?

 

3 hours ago, Markus Hanke said:

It’s much more than an assumption - it’s a necessary consequence of the laws of gravity, which are exceedingly well tested.

One could also say the laws of gravity make it impossible for space to expand because it would take objects longer than predicted to fall as distances increase.

As long as our units of distance and time remain proportional to c, there is no change in the laws.

 

3 hours ago, Markus Hanke said:

18 hours ago, bangstrom said:

With either scenario the observations are identical

They are not. To give one example - metric expansion is a function of distance, so the further out you look, the higher recession velocities are. This is true for all directions. How do you replicate this with ‘shrinking matter’, which depends only on the local rate of shrinkage?

The observations of both scenarios are identical. There is no observational difference whether the universe is expanding while the atomic scale remains static or if the radius of the universe remains large and static while the all material within grows smaller. It works both ways.

If the atomic scale in the distant universe was progressively larger with atoms emitting light in wavelengths proportional to their size, we should see the same degree of redshifting with distance that we observe with the Hubble rate.

One advantage of caracal’s model is that it is obvious from the start that galactic redshifts are not recessional velocities. They are indicators of a universal rate of change. They are not recessional velocities that can be used as reliable indicators of distance and time. This is not as obvious from the Standard Model BB theory.

 

[beecee]

6 hours ago, bangstrom said:

3000K is an assumption because it is a theoretical calculation and not a direct observation. It may be explainable but it is still an assumption based on another assumption that galactic redshifts necessarily indicate expansion. 

I may not be a GR giant, nor a physics giant, but I really find that hard to accept and believe in these days of giant particle accelerators etc. 

On your overall claims re universe or rulers shrinking, GR did originally tell us that the universe was dynamic, that is expanding or contraction. Nothing about atoms, planets, solar systems, galactic groups shrinking, just that the universe was expanding or contracting. Hubble not long after solved that for Albert with cosmological redshift and expansion. 

While expansion is only over large scales, and gravity decouples that expansion over galactic group scales, the other three forces also do a job in maintaining a planet stay solid, a body stays in one piece as is, and atoms molecules etc also hold their positions, that is the EMF, strong and weak nuclei forces.

 

[Markus Hanke]

20 hours ago, bangstrom said:

In other words, atoms today are small scale models of atoms in the distant past

That is a rescaling.

20 hours ago, bangstrom said:

In the expansion model, what was the distance of a light year when the universe had a radius of one half a light year.

I don’t understand this question...can you explain?

20 hours ago, bangstrom said:

One could also say the laws of gravity make it impossible for space to expand because it would take objects longer than predicted to fall as distances increase.

 

Well, that’s exactly what actually happens to light from distant sources...it’s in free fall, after all.

20 hours ago, bangstrom said:

As long as our units of distance and time remain proportional to c, there is no change in the laws.

Suppose you have a system described by a hypothetical Lagrangian of the form

\[L=\frac{a}{r^2} - \frac{b}{r}\]

wherein a and b are dimensionless constants. What happens to the Lagrangian when distances shrink by half, ie you perform a rescaling r’=1/2r?

This is simply to demonstrate the principle, obviously real-world Lagrangians don’t look like this.

20 hours ago, bangstrom said:

If the atomic scale in the distant universe was progressively larger with atoms emitting light in wavelengths proportional to their size

The wavelengths aren’t proportional to the size of the atom, they are determined by the structure of the quantum mechanical orbitals - which are, again, not scale invariant, since the potential term in the Schrödinger equation isn’t scale invariant (never even mind the QFTs underlying this).

20 hours ago, bangstrom said:

One advantage of caracal’s model is that it is obvious from the start that galactic redshifts are not recessional velocities.

You didn’t address my previous objection - redshift increases as the observed object gets farther away. They depend on distance, not any local quantity.

20 hours ago, bangstrom said:

No one is saying atoms can’t change in size.

Actually, that’s pretty much what quantum field theory is in fact saying, since none of the beta function of real-world quantum fields vanish. Scale invariance is quite a complicated topic, but a very basic overview can be found here:

https://en.m.wikipedia.org/wiki/Scale_invariance
 

https://en.m.wikipedia.org/wiki/Beta_function_(physics)

Edited March 2, 2022 by Markus Hanke

[bangstrom]

On 2/28/2022 at 9:42 PM, Genady said:

On 2/28/2022 at 8:42 PM, bangstrom said:

The galaxies are gravitationally bound but they exist within a far greater gravitationally bound object which is the universe itself so how does gravity prevent galaxies from expanding while allowing the universe to expand?

GR equations - not words - show how it happens.

In the Big Bang expansion theory.

If the universe is expanding against gravity, then the galaxies should also be expanding but to a lesser extent since the gravitational bounding within the galaxies is locally greater than that of the universe in general. We as observers should observe no expansion within our galaxy since we are expanding by the same amount as the rest of the galaxy but we should see the universe expand because the universe is expanding at a greater rate than are the galaxies.

However, in the shrinking matter theory.

The universe has always had the same radius and is not expanding at all but it appears to be expanding because the material within is uniformly growing smaller with time. For example, if we and our material world grow smaller by one tenth, then the universe should appear to grow larger by one tenth. So the appearance of expansion is directly proportional to the contraction of matter.

 

 

 

[Genady]

17 minutes ago, bangstrom said:

In the Big Bang expansion theory.

If the universe is expanding against gravity, then the galaxies should also be expanding but to a lesser extent since the gravitational bounding within the galaxies is locally greater than that of the universe in general.

 

 

 

This is NOT what the GR equations show. This is just wrong.

[Markus Hanke]

12 hours ago, bangstrom said:

If the universe is expanding against gravity, then the galaxies should also be expanding but to a lesser extent since the gravitational bounding within the galaxies is locally greater than that of the universe in general.

This will eventually be true in the distant future, assuming an accelerated rate. Right now, even for free space the expansion only becomes apparent on scales of ~MPc, so it isn’t detectable within galaxies (I assume you mean empty space between stars).

12 hours ago, bangstrom said:

The universe has always had the same radius and is not expanding at all

What mechanism keeps metric expansion at exactly zero?

12 hours ago, bangstrom said:

For example, if we and our material world grow smaller by one tenth, then the universe should appear to grow larger by one tenth. So the appearance of expansion is directly proportional to the contraction of matter.

This would imply that redshift is the same for all distant objects, since it depends only on our local rate of shrinkage. But this is not what we see at all.

Edited March 5, 2022 by Markus Hanke

[bangstrom]

21 hours ago, Genady said:

 

 

8 hours ago, Markus Hanke said:

 

 

21 hours ago, Genady said:

21 hours ago, bangstrom said:

In the Big Bang expansion theory.

If the universe is expanding against gravity, then the galaxies should also be expanding but to a lesser extent since the gravitational bounding within the galaxies is locally greater than that of the universe in general.

 

 

 

This is NOT what the GR equations show. This is just wrong.

 You are possibly right and I do find it to be a strange way of looking at things.

8 hours ago, Markus Hanke said:

21 hours ago, bangstrom said:

For example, if we and our material world grow smaller by one tenth, then the universe should appear to grow larger by one tenth. So the appearance of expansion is directly proportional to the contraction of matter.

This would imply that redshift is the same for all distant objects, since it depends only on our local rate of shrinkage. But this is not what we see at all.

As we look into greater distances of space, we see galaxies progressively less expanded than our own with atoms larger than our own emitting light in wavelengths proportional to their larger sizes so we see light redshifting with distance.

Edited March 5, 2022 by bangstrom
Quotes by mistake

[bangstrom]

On 3/1/2022 at 7:57 PM, Markus Hanke said:

The wavelengths aren’t proportional to the size of the atom, they are determined by the structure of the quantum mechanical orbitals - which are, again, not scale invariant, since the potential term in the Schrödinger equation isn’t scale invariant (never even mind the QFTs underlying this).

As I understand, distance and time are measured the same in all reference frames but they vary from one inertial frame to the next which is why we can observe redshifts increasing with distance. The environment from which light is emitted doesn’t vary with just differences in space and time alone but with the combined effects of both space and time simultaneously “spacetime”.

In cosmology, we can’t deal with changes in spacetime because there are too many variables, so time is artificially set as a co-moving coordinate while expanding space is considered as the driver of change. This is the expansion model.

In the shrinking matter model, space is set as a co-moving coordinate while time is considered as the agent of change. In this model, atoms emit light in longer wavelengths not just because of their larger size but they are of a lower (not as contracted) energy level.

Everything within each reference frame remains proportional so I see no problem with scaling.

[Markus Hanke]

21 hours ago, bangstrom said:

As I understand, distance and time are measured the same in all reference frames but they vary from one inertial frame to the next which is why we can observe redshifts increasing with distance.

It’s just that metric expansion is accumulative - the more space you need to traverse, the more expansion you get.

21 hours ago, bangstrom said:

In cosmology, we can’t deal with changes in spacetime because there are too many variables

What do you mean by this?

21 hours ago, bangstrom said:

This is the expansion model.

‘Expansion’ is actually a bit of a misnomer (originating in differential geometry) - really all it is is that measurements of distance depend on when they are taken; there’s not really any substance somehow expanding like dough in an oven.

21 hours ago, bangstrom said:

Everything within each reference frame remains proportional so I see no problem with scaling.

See my comment over on the other thread. We could go back-and-forth on this until the cows come home, but ultimately the only way to be sure whether this idea actually works or not is to demonstrate it mathematically. Can you scale down the wave function of a real world atom such as hydrogen without violating or changing any physics, such that the exact observations of cosmology are reproduced? Can you then extend the same procedure to all other elements (unfortunately this could only be demonstrated numerically)? Can you scale down the Standard Model so that all particles and interactions remain what they are?

I maintain this isn’t possible, not even remotely, for all and any of the reasons already mentioned (and I say this because I’ve been learning the maths of all this stuff for some time). But if someone can put forward a formalism, I’ll be more than happy to look at it - if only just for intellectual curiosity. But you know me by now, I’m by and large a mainstream guy, so it would require some pretty extraordinary and persuasive mathematical arguments for me to even begin taking this seriously. And that’s not an unreasonable stance either.

Edited March 6, 2022 by Markus Hanke

[bangstrom]

3 hours ago, Markus Hanke said:

It’s just that metric expansion is accumulative - the more space you need to traverse, the more expansion you get.

That assumes that space is expanding but that is not the model in question where space is not expanding.

3 hours ago, Markus Hanke said:

 

 

3 hours ago, Markus Hanke said:

On 3/5/2022 at 6:00 AM, bangstrom said:

In cosmology, we can’t deal with changes in spacetime because there are too many variables

What do you mean by this?

If our observations are due to changes in both space and time simultaneously (and I find this to be a likely possibility) we would have no idea if the dominate change is space or time or anywhere in between or I they are both scaling up or both scaling down. Those are too many variables to make a model.

36 minutes ago, bangstrom said:

Expansion’ is actually a bit of a misnomer (originating in differential geometry) - really all it is is that measurements of distance depend on when they are taken; there’s not really any substance somehow expanding like dough in an oven.

 

Relative to the radius of the universe, the scale of of matter is growing smaller with time but relative to the scale of matter, the radius of the universe is growing larger.

The only evidence that we have for either possibility is the redshifting of light from distant galaxies. I don’t see how we can say one is true and the other false since they are just a matter of perspective.

All the properties of matter and as well as motion and inertia can only be recognized or measured in reference to other bits of matter. The condition of the vacuum in no way affects the senses. This is what Einstein called “Mach’s principle”.

I find it more realistic to consider cosmological changes in reference to changes in matter rather than to changes in the vacuum of space but can see how it can be modeled either way. A more realistic model should be less prone to errors in interpretation.

3 hours ago, Markus Hanke said:

We could go back-and-forth on this until the cows come home, but ultimately the only way to be sure whether this idea actually works or not is to demonstrate it mathematically.

I don’t see how we can say whether the universe is expanding or if the material world is growing smaller since our only view from inside should be identical either way.

I have seen the problem expressed to the contrary of the we can view as, “If the universe were to suddenly double in size we would not be able to tell the difference and the math is only as good as our assumptions that go into it.

 

Edited March 6, 2022 by bangstrom
removed a duplicate

[Markus Hanke]

12 hours ago, bangstrom said:

That assumes that space is expanding but that is not the model in question where space is not expanding.

So what mechanism stops space from expanding, and keeps it exactly static (which is not an equilibrium state)?

12 hours ago, bangstrom said:

the scale of of matter is growing smaller with time

Like I said in my last post, you need to first of all show that this in fact possible within the framework of known physics - until then, all further speculations based on this are moot.

12 hours ago, bangstrom said:

A more realistic model should be less prone to errors in interpretation.

A more realistic model must:

1. Accord with already known physics

2. Reproduce the same observational predictions as the old one

3. Make new predictions that the old one couldn’t 

12 hours ago, bangstrom said:

they are just a matter of perspective.

It’s for you to show that this is in fact true.

12 hours ago, bangstrom said:

since our only view from inside should be identical either way.

Again, it’s down to you to show that this is in fact true

[MigL]

I think a reality check is in order before this goes farther ...

Bangstrom ( and Caracal, in the other thred ) does not seem to realize how expansion actually works.

The Cosmological Constant, responsible for expansion, is just that, a constant term appended to the Einstein equations which describe gravity, which acts 'opposite' the gravitational term, and was originally intended to balance the equations so as to keep the universe static.
Since the gravitational terms are variable, but the onstant is not, its effects only become apparent when the gravitational terms are weak enough that the Cosmological Constant exceeds them in magnitude, and the Enstein equations then no longer result in attractive gravity, but rather, cosmological expansion.
IOW, we would see expansion only when gravity is weak enough that the Cosmological Constant is able to exceed the threshold of gravitational attraction.

And the really great part is, that is exactly what we observe.
We don't see spaces between our constituent atoms increase, or the Earth getting larger, or planets and stars moving apart, or even galaxies getting bigger, simply because they are gravitationally bound, and the Cosmological Constant is very small, and below the threshold of the gravitational attraction.
We start to note expansion at large intergalactic and intergalactic cluster distances, where gravitational attraction is very small, and the Cosmological Constant tops the threshold of gravitational attraction, and exceeds it.
That observational evidence fits in neatly with our theoretical assumptions.

A 'shrinking everything' theory, assumes that everything shrinks in scale so that all effects are preserved .
( and as Markus argues that isn't possible )
But we know , from observation, that there has to be a 'cut-off', where, below  intergalactic scales this effect is no longer apparent.
So either your theory is a non-starter, as it doesn't apply to the reality, or, you need to get back to the drawing board, and come up with a suitable mechanism for your theory to maintain the observed cut-off, and comply with reality.

[bangstrom]

3 hours ago, MigL said:

I think a reality check is in order before this goes farther ...

Bangstrom ( and Caracal, in the other thred ) does not seem to realize how expansion actually works.

This is the way expansion “actually” works, when observations fail to match the theory a fudge factor is added to bring theory in line with observation. Examples include, Guth’s inflation, dark energy, and the Cosmological Constant-” lambda”.  The CC is a mathematical correction- not a known law of physics.

3 hours ago, MigL said:

But we know , from observation, that there has to be a 'cut-off', where, below  intergalactic scales this effect is no longer apparent.

If space is expanding, atoms should also expand since they are almost entirely empty space. Contraction theory explains the sharp 'cut-off' where material contracts while space remains unchanged. The BBT adds the Cosmological Constant when needed and drops it when not.

 

3 hours ago, MigL said:

And the really great part is, that is exactly what we observe.
We don't see spaces between our constituent atoms increase,

Atoms in the primal universe must have been much closer together for the fusion of hydrogen into helium and lithium to take place.

[MigL]

8 minutes ago, bangstrom said:

when observations fail to match the theory a fudge factor is added to bring theory in line with observation. Examples include, Guth’s inflation, dark energy, and the Cosmological Constant-” lambda”. 

Not quite.
A Guth's intent with inflation was to explain the homogeneity and isotropy of the universe.
For distant parts of the universe, where light ( and information ) can never be in contact to establish isotropy/homogeneity, there had to have been a time in the past, where/when these distant parts were in causal contact ( light/information could traverse the distance between them ). Inflation provided the mechanism, and slots in well with the electroweak symmetry break, and Higgs mechanism.

Dark Energy, Cosmological Constant; different names, same function.

16 minutes ago, bangstrom said:

If space is expanding, atoms should also expand since they are almost entirely empty space.

If there are a lot of atoms, there is a lot of mass/energy/momentum and therefore a lot of gravity.
Did you read, and were you able to comprehend, the rest of my post, and that the Cosmological Constant has to exceed the threshold of the gravitational bound for expansion to occurr ?
This only happens in intergalactic spaces where the concentration of mass/energy is low enough such that gravity is negligible, and exceeded by the Cosmological constant ( do you prefer dark energy ? ).

22 minutes ago, bangstrom said:

Atoms in the primal universe must have been much closer together for the fusion of hydrogen into helium and lithium to take place.

Or they didn't need to be, saving us the problems associated with scaling of other forces ( as Markus has repeatedly mentioned ), because observations agree just fine with expansion.