Neither do you, apparently. — Haglund

Well, you don’t have an organised approach to explaining. There’s that.

"The Cosmos is deemed to be flat because it has the critical mass..." — Metaphysician Undercover

What, you have never heard this before? Standard cosmology.

https://astronomy.swin.edu.au/cosmos/c/Critical+Density

It depends what you call an organized approach. All is there. The particles (C and U), the charges (three of them), the Lagrangians (excuses for the term used on this forum), a particle shape, which might cause problems for short-range behavior, but at the distances involved should pose no problem. The difficulty lies in assigning coupling strengths for the strong color interaction.

Lagrangians (excuses for the term used on this forum) — Haglund

Kinetic energy minus potential energy? Or that functional used in path integrals? The term comes up over and over it seems.

What, you have never heard this before? Standard cosmology. — apokrisis

There's a lot of standard cosmology which to anyone who takes any amount of time to think about, will be apprehended as fictional. Look at Haglund's explanation of mass for example:

In the standard model this is done by making massless matter interact with a fictitious matter field, with unbelievable properties (a non-zero value of the vacuum expectation value, for which no reason is given; it's just posited). But the mass can also emerge if massless particles interact amongst themselves. Pure kinetic energy turned massive. — Haglund

Your referenced page on critical density offers another very good example:

The ‘critical density’ is the average density of matter required for the Universe to just halt its expansion, but only after an infinite time. A Universe with the critical density is said to be flat. — https://astronomy.swin.edu.au/cosmos/c/Critical+Density

Notice, critical density is the density required to make the universe halt its expansion, after an infinite time. Does that not seem strange to you? Think about it. They've managed to figure out how much density is required such that the universe will actually halt its expansion, but the actual halting of expansion will only occur after an infinite amount of time has passed.

There's a lot of standard cosmology which to anyone who takes any amount of time to think about, will be apprehended as fictional. — Metaphysician Undercover

....said every crackpot ever

Tell me then, how do you make sense of the quote I took from your referenced page? How is "critical density" supposed to make a universe halt its expansion after an infinite amount of time?

General relativity's equation of state says the universe is a balance of the positive potential of its kinetically spreading mass-energy content and the negative potential of the gravitational attraction of that same mass-energy content.

So one blows. The other sucks.

The blowing gets ever weaker. The mass-energy content gets colder and colder, and thus less kinetic as time marches on.

But the sucking also gets ever weaker. The mass-energy content gets more and more spread out and so exerts an ever smaller gravitational force.

If the two sides of the equation remain in balance, then the whole shebang can coast along forever - continuously spreading and cooling - to reach its heat death at the end of time.

Note that in the updated picture - the current Lamda-CDM concordance model - the end of time (as the effective end of all discernible change) now arrives at a finite future date.

Dark energy is acting to accelerate the underlying metric expansion - the spreading. And so the cooling will reach a finite cut-off where kinetic energy can't be drained out of the largest cosmic light cone as light can no longer shift fast enough to cross the cosmic event horizon.

In effect, our visible corner of the cosmos will have fallen down a black hole about 36 billion light years across (about double its current size). But it won't be a big deal as all its particle content, and any blackholes, will also be long gone.

The only thing left will be the fizzle of virtual photons with a blackbody radiation to match a temperature of absolute zero.

But hey, why walk before we can run? Let's deal with the Friedmann–Lemaître–Robertson–Walker metric before we add the wrinkle of the Lamda-CDM concordance model. Let's hear you rant and rave a little more about the vanilla description for a bit.

Tell us again how Einstein got it so wrong and MU gets it so right. :rofl:

Forget it.

In effect, our visible corner of the cosmos will have fallen down a black hole about 36 billion light years across (about double its current size). But it won't be a big deal as all its particle content, and any blackholes, will also be long gone. — apokrisis

The size of the current universe is about 90 billion jy. Not 36 billion. Small detail...

The only thing left will be the fizzle of virtual photons with a blackbody radiation to match a temperature of absolute zero. — apokrisis

Virtual photons with a black body radiation? What does that mean? The more I read of you the less I think you understand anything...

But hey, why walk before we can run? Let's deal with the Friedmann–Lemaître–Robertson–Walker metric before we add the wrinkle of the Lamda-CDM concordance model. Let's hear you rant and rave a little more about the vanilla description for a bit. — apokrisis

Or you talk chocolate about it. MU is at least truly interested...

the end of time (as the effective end of all discernible change) now arrives at a finite future date. — apokrisis

Chocolate talk. "The end of time happens 5-01-3067000000000." :lol:

Forget it. — Haglund

:grin:

You're right. The figures given by Lineweaver are that the current distance to our cosmic event horizon is 16 billion light-years, and the eventual maximum distance will be 18 billion light years. So there won't be a doubling. We are just about there.

See figs 2 and 3 of https://www.mso.anu.edu.au/~charley/papers/mepp.pdf for both that and the argument that all that's left is blackbody radiation with a wavelength the size of the entire cosmic event horizon.

You're right. The figures given by Lineweaver are that the current distance to our cosmic event horizon is 16 billion light-years, and the eventual maximum distance will be 18 billion light years. So there won't be a doubling. We are just about there. — apokrisis

The current distance is about 45 billion ly.

See figs 2 and 3 of https://www.mso.anu.edu.au/~charley/papers/mepp.pdf for both that and the argument that all that's left is blackbody radiation with a wavelength the size of the entire cosmic event horizon. — apokrisis

Yes. But the photons ain't virtual.

The current distance is about 45 billion ly. — Haglund

You’re confusing the particle horizon with the event horizon. But nice try. :wink:

They are one and the sane. No they're not! The event horizon lies even outside of the observable universe! Sorry! :wink:

As usual, you seem deeply confused about even simple stuff.

The particle horizon differs from the cosmic event horizon, in that the particle horizon represents the largest comoving distance from which light could have reached the observer by a specific time, while the event horizon is the largest comoving distance from which light emitted now can ever reach the observer in the future.[3] The current distance to our cosmic event horizon is about five gigaparsecs (16 billion light-years), well within our observable range given by the particle horizon.

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

The ones deeply confused are you and Wiki. Think for yourself instead of quoting Wiki! :wink:

But the photons ain't virtual. — Haglund

Oh, and this. It’s Hawking radiation. So pulled out of the vacuum by the event horizon.

Think for yourself instead of quoting Wiki! — Haglund

You apparently couldn’t follow Lineweaver’s paper so I tried something that was hopefully more your level.

(I see Wiki was in fact quoting Lineweaver’s SciAm article. This Lineweaver must be a real bum, eh? :razz: )

Just calculate the Schwarzschild radius of the mass in the observable universe...

Oh, and this. It’s Hawking radiation. So pulled out of the vacuum by the event horizon — apokrisis

Hawking radiation is real photons and neutrinos. A black hole takes much longer to evaporate than the expansion takes to go beserk. So it will be the black holes torn apart. Everything in it will stay in it. But since most matter in it consists of preons and their antis, only real anti neutrinos and photons are left which can't react with the neutrinos that are left. They will get lost in space and no energy will be left.

You apparently couldn’t follow Lineweaver’s paper so I tried something that was hopefully more your level. — apokrisis

It's not that I cant follow. I dont want. to follow. You maybe need a teacher but I dont need no more... You just say that to show your so-called high intelligence... :wink:

Oh, and this. It’s Hawking radiation. So pulled out of the vacuum by the event horizon. — apokrisis

All matter is pulled out of the virtual once. So all matter is a kind if long lived virtual particle. All quarks and leptons will return into the vacuum again, except neutrinos, anti neutrinos and photons. If the anti neutrinos can escape the holes before the rip gets grip (hey! The rip gets grip!) then they will annihilate with the neutrino background. And only real photons will be left. Time will continue infinitely. At the center singularity a new bang can bang happily. :yawn:

It's good that even despite the inconclusive discussion about the actual topic that we've at least been able to sort out the fate of the Universe. Makes you think your day hasn't been entirely wasted.

Makes you think your day hasn't been entirely wasted. — Wayfarer

:grin:

It's not that I cant follow. I dont want. to follow. — Haglund

:up:

If the two sides of the equation remain in balance, then the whole shebang can coast along forever - continuously spreading and cooling - to reach its heat death at the end of time. — apokrisis

As I said, fiction. But regardless of whether it's fiction or not, your explanation is very clearly inconsistent with your referenced article. The article explicitly says "but only after an infinite time". Therefore the article's explanation of "critical density" implies no end of time, yet your explanation states "at the end of time". A very clear contradiction in the two fictions, yet you give yours the same name, "critical density", as the other.

Note that in the updated picture - the current Lamda-CDM concordance model - the end of time (as the effective end of all discernible change) now arrives at a finite future date. — apokrisis

So, can I conclude 'end of time at a finite future', means no "critical density", which also means no flat universe? The "flat" is just an unrealistic ideal, like I've been trying to tell you. Therefore "flat universe", and "critical density", are simply fictions. How long do you think before the "updated picture" is also recognized as unreliable, is changed, and is also seen as a fiction?

Tell us again how Einstein got it so wrong and MU gets it so right. :rofl: — apokrisis

Since all cosmology produced by Einsteinian theory ends up needing to be "updated" because it's wrong, and the updates involve making further exceptions for the failings of general relativity, I think it's very clear that Einstein got it wrong.

Look at the problem with the concept of "mass" which I mentioned. By Newton's principles, an object's 'resistance to change' is attributed to its momentum, which is a product of mass and velocity. Change to velocity requires acceleration, and this is offset by the mass of the object, so "mass" here represents the resistance to change. But kinetic energy, as the capacity to change an object's momentum, represented as one half the product of the mass with the square of the velocity, already has acceleration factored within it.

The problem with the concept of kinetic energy is that acceleration is not well understood, so any representation of it is just an approximation. Now in relativistic physics we have kinetic energy with no mass, in the form of electromagnetism, light, or photons. If you look, you can see a very clear problem with the concept of 'resistance to change'. In Newtonian physics 'resistance to change' was a property of mass. In the concept of "kinetic energy" an approximation is used to account for this property of mass, such that "resistance to change" is offset by the approximation of "acceleration". An approximation is used because acceleration is not well understood.

That approximation allows that inertia (resistance to change) can be attributed to kinetic energy. But there is an inversion which is not accounted for. Kinetic energy is the capacity to effect change, to cause change, and inertia is the capacity to resist change. The two could be thought to balance each other in a static situation. However, in any act of change, some energy is lost to the system (friction for example), or whatever it is which is supposed to contain the system (it can be expressed as entropy). So there must necessarily be a discrepancy between the "inertia" attributed to kinetic energy, as a potential cause, and the "inertia" attributed to mass, as resistance, because of the reality of entropy. More "inertia" as kinetic energy is required than the amount of "inertia" of mass, to have a balance. And, attempting to produce an equivalence between these two is a mistake, because the equations used to represent acceleration are only approximations, and they cannot account for the reality of the lost energy in real acceleration. The relativity theory does not give the tools to determine how the energy is lost, because equivalence is assumed, under the one name "inertia". Hence the glaring problem in modern physics, that many processes are understood as reversible.

It's good that even despite the inconclusive discussion about the actual topic that we've at least been able to sort out the fate of the Universe. Makes you think your day hasn't been entirely wasted. — Wayfarer

What happened to the topic? I'd conclude that there is substantial disagreement with respect to the meaning of the principal terms "necessity" and "causation".

My conclusion is that scientific law is where logical necessity meets physical causation. I haven't seen an argument to dissuade me of that original idea, although I keep an open mind.

As I said, fiction. But regardless of whether it's fiction or not, your explanation is very clearly inconsistent with your referenced article. The article explicitly says "but only after an infinite time". Therefore the article's explanation of "critical density" implies no end of time, yet your explanation states "at the end of time". A very clear contradiction in the two fictions, yet you give yours the same name, "critical density", as the other — Metaphysician Undercover

Good one! :up: