Lambda-CDM theory - Woo or not?

[ben m]

And to think you accuse *me* of goal post shifting? Holy cow! Your goalposts have twin turbo's! We're not calculating the pressures of various objects on one another, we're calculating the PRESSURE OF A VACUUM on ONE object that might exist inside that vacuum. Guthianity doesn't have second plates or second objects to work with ben. Try again, only start with only one mass blob and a VACUUM. That's all Guthainity has to work with.

Why are we calculating the pressure of a vacuum on an object? Why would you ignore gravity when figuring out the effects of something? Did you turn it off? Did someone do an equivalence-principle experiment that proved GR wrong?

 

[Tubbythin]

Irony overload. I think only sol really appreciates the fact that EM field energy is kinetic energy. The rest of you, well, your statements speak for themselves. We even know that the EM field is the carrier particle of the kinetic energy transfer because the materials make a difference.

Of course the materials make a difference. They provide the boundary conditions. The rest of the paragraph is just word salad.

When were you going to accept the fact that you've never shown any appreciation for the difference between "relative pressure" and "absolute pressure"? When did you intend to show any evidence that Guth's mythical vacuum contains negative pressure?

Answer the questions I just put to you in my other post.

 

[Reality Check]

A constant in a math formula is NOT a PHYSICAL CAUSE RC. It's just a constant in a math formula.

You misunderstand: Nothing in any math formula is a PHYSICAL CAUSE MM. The F in F=ma is just a F. It is the symbol F. In this math formula it REPRERSENTS a physical cause called force.
A constant in a math formula can REPRESENT a physical cause.

The simple science that you still cannot understand is that a positive cosmological constant REPRESENTS a physical cause of dark energy. Just like the stress-energy energy tensor REPRESENTS the cause of the curvature of spacetime.

 

[Michael Mozina]

Of course the materials make a difference. They provide the boundary conditions.

No. The physical boundary conditions provide the boundary conditions. The material effects demonstrate that the EM field does the work.

The rest of the paragraph is just word salad.

That fact you didn't acknowledge my point about kinetic energy is the key issue here IMO. If you can't understand that the photon *IS* a form of kinetic energy, there's really not much more we can discuss. Of course kinetic energy is involved in the transfer process TBT! It's impossible for it NOT to involve a kinetic energy transfer. That transfer process takes place on ALL SIX SIDES of all the plates, not just one. There is more kinetic energy on the outside of the plates, and less kinetic energy between the plates. Likewise there is more quantum pressure on the outside of the plates and less quantum pressure between them. You still can't distinguish between RELATIVE pressure and ABSOLUTE pressure, and none of this has anything to do with the "pressure of the vacuum". The pressure of the vacuum itself can be ANY pressure we select, and the QM pressures will still work, and still involve force on ALL SIDES of the plates, not just one.

Since you refuse to acknowledge that it's a kinetic energy exchange, no subatomic merit badge for you.

 

[Michael Mozina]

Why are we calculating the pressure of a vacuum on an object?

Because that's all Guth had to work with ben.

Why would you ignore gravity when figuring out the effects of something?

I'm not. It's going to cause your mass thingy to want to implode. What did you say was going to stop that from happening? Oh ya, mythical new forms of (now dead) energy.

Did you turn it off? Did someone do an equivalence-principle experiment that proved GR wrong?

Not at all. Gravity works against you, not for you.

 

[Michael Mozina]

The simple science that you still cannot understand is that a positive cosmological constant REPRESENTS a physical cause of dark energy.

The simple fact that you still cannot understand is that you've shown no physical, empirical cause/effect link between the movement of mass and "dark energy". You might as well be claiming that "Godenergydidit" or "Magicenergydidit".

 

[Tubbythin]

No. The physical boundary conditions provide the boundary conditions. The material effects demonstrate that the EM field does the work.

They provide the boundary conditions by only allowing normal modes which have nodes at the two boundaries.

That fact you didn't acknowledge my point about kinetic energy is the key issue here IMO.

I didn't acknowledge your point because you didn't have a point.

If you can't understand that the photon *IS* a form of kinetic energy, there's really not much more we can discuss.

A photon is a quantum of the electromagnetic field. It carries energy. You can think of it as kinetic energy if you like. It isn't a form of kinetic energy any more than a proton or a neutron or a neutrino or an electron or an ice cube or a person is kinetic energy. That doesn't make any sense in terms of English.

Of course kinetic energy is involved in the transfer process TBT! It's impossible for it NOT to involve a kinetic energy transfer. That transfer process takes place on ALL SIX SIDES of all the plates, not just one. There is more kinetic energy on the outside of the plates, and less kinetic energy between the plates. Likewise there is more quantum pressure on the outside of the plates and less quantum pressure between them. You still can't distinguish between RELATIVE pressure and ABSOLUTE pressure, and none of this has anything to do with the "pressure of the vacuum". The pressure of the vacuum itself can be ANY pressure we select, and the QM pressures will still work, and still involve force on ALL SIDES of the plates, not just one.

You can make these claims as many times as you like Michael. But check any standard physics text book and it disagrees with you.

Since you refuse to acknowledge that it's a kinetic energy exchange, no subatomic merit badge for you.

It isn't a kinetic energy exchange. If it was you'd be able to find me hundreds of references to say it were.

 

[Reality Check]

The simple fact that you still cannot understand is that you've shown no physical, empirical cause/effect link between the movement of mass and "dark energy".

The simple fact is that you continue to document your ignorance, Michael Mozina.

A positive cosmological constant is not a "movement of mass".

Dark energy and the cosmological constant as a candidate for its cause.
There is a physical, empirical cause/effect between a positive cosmological constant and dark energy.
N.B. This is empirical as used by science, not the imaginary 'empirical' that only exists in your head.
A positive cosmological constant has the properties for a cause of dark energy !

"The cosmological constant has negative pressure equal to its energy density and so causes the expansion of the universe to accelerate."
​

 

[ben m]

Not at all. Gravity works against you, not for you.

I'm sure you are just about to post a lucid derivation of that fact from the known laws of gravity, i.e. general relativity? Will you point out in which step of (say) Kip Thorne's derivation contains the mistake that you have corrected?

 

[Reality Check]

Because that's all Guth had to work with ben.

That is ignorant, MM. Guth never looked at the pressure of a vacuum on an object. The universe is not an object embedded in a vacuum. The universe is everything - including that vacuum.
The only "pressure of a vacuum on an object" that we are looking at is the example of the negative pressure exerted by the Casimir effect on the sphere & plate in the experiments. This is obviously a negative pressure because

1. The theory says so.
2. The experiments measure a negative pressure.
3. The definition of pressure states that an attractive force results in a negative pressure.

However it looks like you have gone back to your usual ranting about the Casimir effect.


There is overwheming evidence that the universe was once in a hot dense state. This leads to various problems

• A prediction that there should be magnetic-monopoles produced that we can detect today.
• Horizon problem
• Flatness problem

How do we solve these problems?
Inflation is the best current solution.
Guth's concept was that the universe underwent a phase transition very early on that established a scalar field (called the inflation field). This exerts a negative pressure. In this case the pressure is so enormous that the universe expands by a factor of 10^78. That solves the problems above.

 

[sol invictus]

I'm sure you are just about to post a lucid derivation of that fact from the known laws of gravity, i.e. general relativity? Will you point out in which step of (say) Kip Thorne's derivation contains the mistake that you have corrected?

The conclusion.

 

[Wangler]

Maybe the cold of CDM is woo?

A recent simulation seems to shed some doubt that the cold dark matter is indeed cold.

These results provide direct evidence against the notion that the current CDM paradigm successfully accounts for the phenomenology of dark matter at small scales.

I think that this possibility has been suspected for some time.

 

[edd]

Well there's a definite difference between woo and wrong. Lots of LCDM could be wrong - being woo would be a lot worse.