Lambda-CDM theory - Woo or not?

[Michael Mozina]

Well, heat isn't "net energy". Net energy is the sum of all forms of energy, and heat energy isn't the only form.

What "offsets" the heat?

There's gravity too.

Then why doesn't it implode?

So even if you want to (wrongly) insist that gravitational energy is positive, heat energy is still not "positive net energy" because it's not net energy at all.

Epic fail.

The "epic fail" here is your unwillingness to embrace reality. If gravity exists, your party isn't going anywhere, the whole thing is going to implode before the party starts. The heat is the only thing that might save your "thingy" from a complete implosion, but only if there is more energy from "heat" than there is "negative energy" in your gravity! Hoy.

 

[Michael Mozina]

You can't change the pressure on the outside of the plates. The volume between the plates is the only factor that matters when calculating the pressure between the plates.

This is where you are absolutely and positively *WRONG*. The only thing that matters is the physical process that drives the parade. The "pressure" in this case is "positive" on all sides of all plates. It is simply 'greater' on one side than the other. Period. There is no such thing as "negative pressure in a vacuum". It is a physical impossibility. You can dream up all the mythical math models you wish, but there is no type of "negative pressure" in that chamber. You math model has led you down the primrose path because you *did not consider the actual physics* involved in this process.

The "pressure" of *all* sides of the plates "matter". It is all positive relative to absolute zero. There is "positive pressure' on all sides of the plates from the atoms in the chamber and there is "positive pressure" from the "force" of the carrier particles of EM fields. There is no area inside the chamber or between the plates that experience "negative pressure".

 

[temporalillusion]

I said it's the only factor that matters when calculating the pressure between the plates.

I see a lot of hand waving, and not much explaining.

You talk about the "actual physics" but you haven't provided any, beyond hand waving and statements from personal incredulity.

And a LOT of dodging and ignoring questions. You do realize that the questions I'm asking is trying to find a common ground to work forward from, right?

 

[Ziggurat]

What "offsets" the heat?

I just told you: gravity. But hell, even if it doesn't offset the heat, it still needs to be included or it's not "net energy". A rather simple point which apparently still eludes you.

Then why doesn't it implode?

Why would it?

If gravity exists

What do you mean, "if"? Are you in doubt about that bit?

your party isn't going anywhere, the whole thing is going to implode before the party starts.

That's not what GR says.

The heat is the only thing that might save your "thingy" from a complete implosion, but only if there is more energy from "heat" than there is "negative energy" in your gravity!

Got any calculations to back up that assertion? No, of course you don't. You've never done a single calculation. Because you can't. I've never met someone so intent on telling professional physicists (and there are a number in this thread) that they're all totally wrong while being so completely unable to do what physicists actually do.

Your obsession with the idea that math is leading us down the wrong path apparently stems from the fact that it produces results which contradict your intuition and which you can't understand because you can't do any of the math yourself. Since you don't understand it, it looks like magic to you, so you can't accept that its implications are, in fact, quite real.

Of course, you could prove me wrong easily enough, if what you've claimed about yourself is true. But it isn't, because you're a liar.

 

[Michael Mozina]

I said it's the only factor that matters when calculating the pressure between the plates.

But the math formula that you chose to use, does not in fact calculate the *actual* pressure between the plates. You are only calculating the *relative pressure* (compared to the outside plate pressure) between the plates because you have ignored the *outside positive pressure on the plates* by design! You're hopelessly confused by your own math. You did *not* calculate the *actual* (total) pressure between the plates in that math formula. You calculated the *relative* pressure compared to the outside plate pressure.

I see a lot of hand waving, and not much explaining.

I have explained the whole thing now in some detail, as does the WIKI site. The only issue here is that your math formula is a "gross oversimplification" of the actual physical processes at work in the chamber, and your calculation does *not* calculate the *actual pressure* in the chamber. It's a "relative to" sort of calculation at best case that has nothing to do with the *actual pressure* in the chamber. This is another example of you folks failing to understand the physics behind your mathematical models. You don't *get it* when it comes to the actual *physics*, so you can't tell "relative pressure" from "actual pressure".

And a LOT of dodging and ignoring questions. You do realize that the questions I'm asking is trying to find a common ground to work forward from, right?

Sure. That's also why I've spent all this time showing you the limits of your math formula in this specific scenario. In that particular math formula, you specifically chose a *limited* and *relative* reference point for "pressure", nothing more. In no way does this math formula demonstrate a 'negative pressure in a vacuum' which is what Guth requires to make his inflation near singularity thingy do its magic zero-net energy inflation trick.

 

[Ziggurat]

But the math formula that you chose to use, does not in fact calculate the *actual* pressure between the plates. You are only calculating the *relative pressure* (compared to the outside plate pressure) between the plates because you have ignored the *outside positive pressure on the plates* by design!

The outside pressure is close to zero, which is why it doesn't get calculated. In simple terms, the change in energy is related to the fractional volume change. Between the plates, the fractional volume change is large for changes in plate separation. Outside the plates, the fractional volume change is many orders of magnitude smaller. Recall that pressure is
[latex]$P=-\frac{\partial E}{\partial V}$[/latex]
So since the changes in energy outside the plate are so much smaller than changes between the plates, the absolute value of the pressure outside the plates is many orders of magnitude smaller, and can be safely ignored. Which is why the effect is not observable for a single plate in the middle of a large cavity. It doesn't matter if the energy density outside the plates is larger, smaller, or whatever: it hardly changes with changes in plate separation, so its derivative is small and the pressure is close to zero. The pressure between the plates is large and negative.

You're hopelessly confused by your own math. You did *not* calculate the *actual* (total) pressure between the plates in that math formula. You calculated the *relative* pressure compared to the outside plate pressure.

Nope. It's the actual pressure, calculated using the expression I gave above. Energy in the vacuum between the plates increases with increasing separation, therefore pressure is negative. Quite simple, really. But yes, it takes a bit of math. Just like all real physics takes a bit of math: that's what makes it physics and not philosophy.

The only issue here is that your math formula is a "gross oversimplification" of the actual physical processes at work in the chamber, and your calculation does *not* calculate the *actual pressure* in the chamber. It's a "relative to" sort of calculation at best case that has nothing to do with the *actual pressure* in the chamber.

Well, no. You are correct that the calculation is being performed "relative to" something else, but you're completely wrong about what it's relative to. It is not calculated relative to the outside pressure (which is essentially zero). Rather, the energy between the plates is calculated for a displaced plate relative to an undisplaced plate. But both are energies inside the plate. From that calculation we can get the derivative of energy with respect to volume, a.k.a. pressure. But this is in fact an absolute pressure between the plates, not a relative pressure.

In that particular math formula, you specifically chose a *limited* and *relative* reference point for "pressure", nothing more.

Nope. A relative reference point for energy is used, because when you calculate the derivative, only the change matters, you don't need an absolute energy, and you only need the derivative to calculate a pressure. But the pressure is still an absolute pressure, not a relative pressure. Your confusion betrays your ignorance of math.

 

[Tim Thompson]

Subjective Interpretation

Observations are not "empirical experiments".

I disagree. Yes they are empirical experiments. Astronomical observations constitute valid tests of astronomical hypotheses, in exactly the same sense as an experiment in an organic chemistry lab. In both cases there is an hypothesis to test, and the observations serve that purpose. In both cases criteria are established prior to the experiment, whereby either the verification or falsification of the hypothesis can be established. There is no difference between the data gained by astronomical observation to test astronomical hypotheses and the data gained in a controlled laboratory experiment to test a laboratory hypothesis.

The rest of your theory is a completely "subjective interpretation" of that data.

This is also exactly true of everything you have had to say about Birkeland's experiments. You subjectively interpret that Birkeland's data are applicable to the sun and the solar wind. There is no logical difference at all, none, between your theories based on Birkeland's observations and cosmological inflation. They are equally "subjective", as you have chosen to define the concept.

 

[temporalillusion]

But the math formula that you chose to use, does not in fact calculate the *actual* pressure between the plates. You are only calculating the *relative pressure* (compared to the outside plate pressure) between the plates because you have ignored the *outside positive pressure on the plates* by design! You're hopelessly confused by your own math. You did *not* calculate the *actual* (total) pressure between the plates in that math formula. You calculated the *relative* pressure compared to the outside plate pressure.

So please provide the correct formula. Provide the one that illustrates your view.

Or show where the derivation for the formula goes wrong. Or show where the original premise of the derivation is flawed.

Or show something, rather than just making stuff up.

I have explained the whole thing now in some detail, as does the WIKI site.

You have explained nothing, you've made broad declarations, but no explanations. Whenever I try to get a clarification you ignore it all and wander blindly forward.

The wiki site gives the pressure as negative. You fail.

The only issue here is that your math formula is a "gross oversimplification" of the actual physical processes at work in the chamber, and your calculation does *not* calculate the *actual pressure* in the chamber. It's a "relative to" sort of calculation at best case that has nothing to do with the *actual pressure* in the chamber. This is another example of you folks failing to understand the physics behind your mathematical models. You don't *get it* when it comes to the actual *physics*, so you can't tell "relative pressure" from "actual pressure".

So provide the real formula. Provide real data. You whine and whine about real physics but never provide anything real yourself, you simply point at something and say "that's not right" without ever providing the correct way.

I want to calculate the vacuum pressure between the plates, how do I go about it?

Sure. That's also why I've spent all this time showing you the limits of your math formula in this specific scenario.

You've shown nothing, you've SAID many things, but shown nothing.

In that particular math formula, you specifically chose a *limited* and *relative* reference point for "pressure", nothing more.

Where does this reference point get chosen in the formula or derivation? Please point that out.

I suspect you'll reply with more "it can't be this" and "it can't do that", without any indication why. When you say "can't", you can usually show WHY, but you never.. ever.. show anything.

The emperor has no clothes.

 

[Reality Check]

Yes, you are still ignoring them in your math formula. Your math formula of personal choice explicitly does *not* (not, not, not!) pay attention to the "pressure" on the outside of the plates! It explicitly *oversimplifies* the physical process!

That is right - the calculation simplifies the stutation. The formula is for the situation where the plates are in a perfect vacuum (no air pressure).

So lets make this simple for your simple mind:
The plates are not in a perfect vacuum in the experiments.
The experiments are done in low pressure vacuum chambers.
The scientists doing these experiments do them in a very low pressure vacuum for a reason.
The reason is so that the air pressure exerted by the remaining gas in the chambers is negligible compared to the vacuum pressure exerted by the Casimir effect.
Thus the measured forces are due to the Casimir effect.
The measured forces just happen to match the theory.

So now all you have to do is show that the remaining air pressure in the vacuum chambers is such that any Casimir effect could not be measured.

Of course that leaves the fact that the definition of pressure as given in every textbook ever written allows for negative pressures.
Thus your next task is to completely rewrite physics so that only positive pressure is allowed.

 

[Zeuzzz]

 

[Dancing David]

Ah ok, I had thought that it was purely radiation, that makes more sense to talk about heat then.



I was trying to get MM to acknowledge that for his bomb thought experiment, which he's abandoned now I guess




And we don't know if the universe is open or closed.

As usual the real answer is "it depends" and "it's more complicated than that" lol.. thanks!

-----

So MM, you didn't respond to anything but the first part of my post, so I'll post it again so you don't have to scroll back.

If I have an electron and a proton (or whatever you want), and the closer I bring them together, the attractive force between them increases right?

Do you agree with Coulomb's law?

[latex]$$ F=k_e\frac{q_1q_2}{r^2} $$[/latex]

As r approaches zero, what's going to happen to the force? What's the upper limit of that attraction? You can't produce one for the Casimir effect, but you should be able to do so for this since this is your home turf so to speak.

Hypothetically it approaches infinity, do you agree?

How is this any different than the formula for pressure? What do you think happens to the pressure as the distance between the plates goes to zero, if the distance is in the denominator? In an ideal situation with impossibly flat and impossibly parallel and impossibly close plates?



Here again you agree with the wiki article for the Casimir effect.

Let me ask again, for the dozenth time or something, what is the sign for pressure in this forumula?

[latex]$$ \frac{F_c}{A}=-\frac{\hbar c \pi^2}{240a^4} $$[/latex]

If you disagree with the derived formula, at which point does the derivation go wrong in your opinion?



Well the wiki article you say is written by people that got it right claims it. What's the sign on the formula above?



And according to the crew that wrote the wiki article, what's the sign on the formula above?

Oh, you Mathemagician you.

Thanks, you and others have pointed this out over and over.

 

[Michael Mozina]

The outside pressure is close to zero, which is why it doesn't get calculated.

Gah! No. The *outside* QM "force" is not zero, nor is the "pressure". The outside force is "greater than" the QM force between the plates! You specifically selected a formula that *ignores* the outside force on the plates, but it is the QM force on the outside of the plates that "pushes" them together!

Notice the big blue arrows?

I gave up talking to creationists after awhile because when I busted their show, inevitably they simply ignored the evidence. In this case you seem to believe this is some sort of evidence of "negative pressure" in a "vacuum", whereas in the real world it is a measure of QM *force* that has nothing to do with "pressure", and the "force' is applied to *both* sides of *both* plates. You don't understand any of this because all you understand is the math, and you have no clue about the actual physics that this math relates to. It's an *oversimplified math formula* that does nothing to bolster your belief in "negative pressure in a vacuum". There is no "negative pressure" in these experiments, there is always 'positive pressure' in the chamber. There is not a "negative force" either since the force is applied to *all sides of the plates at the same time*.

 

[Michael Mozina]

That is right - the calculation simplifies the stutation. The formula is for the situation where the plates are in a perfect vacuum (no air pressure).

So lets make this simple for your simple mind:

My simple mind? You are the one with the "oversimplified" model here, not me. Your *mind* can't seem to wrap itself around the idea of "quantum force" that *pushes on all sides of the plates*. Your *oversimplified math model does *not* demonstrate "negative pressure", or even "negative force". It is simply represents "more QM force" on one side of the plates than the other! Hoy.

This whole conversation on the Casimir effect is an excellent example of why astronomers are so clueless. You folks do in fact understand math, but when it comes to the actual "physics" of what occurs inside the chamber you are completely and utterly clueless. If the forces worked as you claimed, then there would be no blue arrows on the outside of the plates pushing them together, and the little blue arrows inside the plates would point inward toward one another.

There is no "negative pressure" in a Casimir experiment. There isn't even a "negative force" between them. It's "handy" perhaps to mathematically model it that way, but that oversimplified mathematical representation does not justify your faith in "negative pressure in a vacuum". There is no such thing. That would be physically impossible to actually achieve.

There is no "negative pressure" in that chamber. There is no "negative force" between the plates either. There is simply "more" force on the outside of the plates and "less" force on the inside pushing them apart. You're still hopelessly confused between an oversimplified mathematical model and the "actual physics" of what happens inside the chamber. Like I said before, you folks are *completely* fixated on the math but you really don't understand what that math represents in terms of actual physics. As long as there is a math formula where you can stick in a minus sign, you're convinced you've seen "negative pressure", or "negative force", or "negative temperature". In terms of "absolute* pressure, "absolute" force, or "absolute" temperature however, your math formulas show nothing of the sort.

 

[Tubbythin]

You don't understand any of this because all you understand it math, and you have no clue about the physics that this math relates to. It's an *oversimplified math formula* that does nothing to bolster your belief in "negative pressure in a vacuum".

This ranting and raving from somebody who thought the ideal gas law was relevant to the situation! Unbelievable.

 

[Michael Mozina]

This ranting and raving from somebody who thought the ideal gas law was relevant to the situation! Unbelievable.

If we're describing the actual "pressure" in a vacuum, it is "relevant". No gas, no "pressure".

 

[Ziggurat]

Notice the big blue arrows?

Argument by pictures. Real convincing there. Ever consider actually calculating that force or the corresponding pressure? No, of course not: you can't do any calculations. You can only look at pictures. See spot. See spot run. Run, spot, run!

Nobody is impressed.

in the real world it is a measure of QM *force* that has nothing to do with "pressure"

See, this is why nobody takes you seriously: of course force has something to do with pressure. If you understood the definition of pressure, you'd understand exactly what the relationship between force and pressure is, and why they are rather directly related. But you don't understand what pressure means. Yet again, you demonstrate that your comprehension fails at the most basic level.

You don't understand any of this because all you understand it math, and you have no clue about the physics that this math relates to. It's an *oversimplified math formula*

If this was actually the case, then you should be able to present the correct, unsimplified formula, and demonstrate why it gives a different answer than the "oversimplified" formula gives. But you can't do that, because that would require math, and you can't do math. Yet you're convinced of the answer that the "correct" math would give, even though you can't actually confirm it. Nobody is going to believe anything you say if you can't do the math. You're just like all the other cranks: when the rubber hits the road and it's time for an actual calculation, you can't do anything.

 

[Tubbythin]

If we're describing the actual "pressure" in a vacuum, it is "relevant". No gas, no "pressure".

Nope. No gas, no gas pressure. But other things exert pressure.

 

[Reality Check]

My simple mind? You are the one with the "oversimplified" model here, not me. Your *mind* can't seem to wrap itself around the idea of "quantum force" that *pushes on all sides of the plates*. Your *oversimplified math model does *not* demonstrate "negative pressure", or even "negative force". It is simply represents "more QM force" on one side of the plates than the other! Hoy.
...snipped yet another MM rant about negative pressure...

My mind can itself around the idea of "quantum force" that pushes on all sides of the plates. That is the Casimir effect. That is the negative pressure as shown by the theory and and measured by experiments.

Since you arre incapable of answering questions about the Casimir effect (such as where the math went wrong in deriving a negative pressure), let us look at a basic situation:

Here is a simpler situation (first asked 26 March 2009):

Consider these 2 scenarios

1. A force F pushes on a surface that has an area of A.
2. A force F pulls on a surface that has an area of A.

What is the pressure in these 2 scenarios?
​

If you do not know what pressure is or cannot answer that then:

Is the pressure positive or negative in each of the 2 scenerios?
​

All you have to do is use your definition of pressure (the ideal gas law?) and plug in F and A to get the answers.

 

[Reality Check]

If we're describing the actual "pressure" in a vacuum, it is "relevant". No gas, no "pressure".

We are not discussing the pressure in a gas (however dilute the gas, e.g. in a vacuum chamber).
By definition a vacuum has no gas in it.

Experimentally there is gas involved in the measurement of the Casimir effect. Scientists know this and ignore it because the vacuum chamber is at a low enough pressure to ignore air pressure. That is the reason to use a vacuum chamber (otherwise they would save money and time and do the experiments at room pressure).

You are asserting that the air pressure in the vacuum chamber just happens to act exactly like the Casimir effect (to 1% accuracy) which is a vacuum pressure.
Now prove your assertion by showing the the air pressure between 2 parallel plates exerts a pressure that varies as the fourth power of the distance betwen the plates (as shown experimentally).
For a genius like you this should be simple. But given your track record with questions I will timestamp this question (first asked 1 April 2009).

 

[Michael Mozina]

Nope. No gas, no gas pressure. But other things exert pressure.

What might exert "negative" pressure in a vacuum? What did you intend to add or subtract from a "pure" vacuum to achieve "negative" pressure? Keep in mind that at the level of QM, an all pervasive EM field around Guth's "heat thingy" would push (big blue arrows point inward) *into* Guth's near singularity thingy.