Lambda-CDM theory - Woo or not?

[Tubbythin]

It's a *force* (not pressure) that comes from the EM field. The "pressure" of a "vacuum" has nothing to do with the EM field.

The pressure in a vacuum is due to virtual photons in the vacuum.

I said:

Oh and links to an article on Casimir pressure. Oh, and makes no reference to ideal gases or neutrinos.

To which you said:

Gah. That is because it's a *FORCE*, unrelated to the "pressure" in a vacuum/chamber.

Are you tring to tell me the thing called the "Casimir pressure" is not a pressure? Seriously?

The neutrino example was simply to demonstrate that there is a lot of kinetic energy flowing through everything all the time.

It was an utterly stupid example since its trivial to show it has no effect on the experiment whatsoever.

Er, no. Your side has been claiming this is a form of "negative pressure". It's a "force" unrelated to "pressure" that comes from the EM field.

What? How can it be totally unrelated to pressure? Pressure is force divided by area. We're trying to calculate the force on a plate of a given area. How can you possibly think these things are unrelated? It even gives the final quantity as the force per unit area!

It can attract or repel depending on the geometry involved. It is not a demonstration of "negative pressure" as you folks claimed.

Yes it is.

False. It means that *if no other factors are involved*, it must expand or contract. In the presence of pervasive and persistent EM fields however that may not be true anymore. In such a case EM fields are not necessarily directly related to GR theory so there is no point in stuffing their influence into (inside of) GR theory in a sort of "ad hoc" manner. MHD theory however might come in very handy when looking at external (to the mass objects) energy.

Can you support the above.. Because all the world's leading experts on GR disagree with you completely. Who should we believe? Those who understand GR and the cosmological observations and can use one to the interpret the other. Or some guy who doesn't even understand the cosmic microwave background and tries to disprove the possibility of negative pressure caused by virtual photons by using the ideal classical gas law?

I'm open to a static or non static universe. I'm not actually *claiming* anything about the expansion process other than you cannot empirically demonstrate is has anything at all to do with "space expansion" or "superliminal expansion".

Yes "you" can.

 

[Tubbythin]

It didn't used to be that way. "I don't know" is a valid scientific answer.

My point was that you're not saying "I don't know". I'm fine with "I don't know". What I see as the antithesis of science is the "I don't know, I don't wanna know and I'm gonna hurl abuse at anybody who tries to find out". Which is pretty much how you come across (at least to me).

 

[Michael Mozina]

I try never to refer to expansion as superluminal anyway. I don't think 'superluminal' is a word that can meaningfully be applied to the expansion of the universe (by which I mean the growth in distance between distant objects, not necessarily the growth of space, thanks to the aforementioned caveats).

So far, so good.

So while it might be a big deal to you to take this approach, the model in that paper in order to fit observations requires exactly the same amount of dark matter and dark energy.

MACHO forms of "dark matter" and neutrino forms of dark matter are fine by me, but "dark energy" does not accelerate anything here on Earth, but EM fields certainly can and do accelerate plasma all the time. Every time we get a good thunderstorm around here I watch it happen in nature for free.

It does not let you off the hook from having a dark sector or having to use something other than a Friedmann model.

It seems to me that the only known macro force in nature that is many many OOMS more powerful than gravity, the EM field offers us the most hope of explaining an accelerating plasma universe.

Note also that recession velocities greater than c do not require either the L or the CD of LCDM. And I don't think you would want to argue to take the M out of what's left...

We're left with an EM acceleration of a physical universe that is mostly made of plasma, aka "EU theory".

 

[Michael Mozina]

My point was that you're not saying "I don't know". I'm fine with "I don't know". What I see as the antithesis of science is the "I don't know, I don't wanna know and I'm gonna hurl abuse at anybody who tries to find out". Which is pretty much how you come across (at least to me).

Knowing from an empirical standpoint is something I also appreciate and "crave" just as much as you do. I simply see the difference between empirical truth, and "wishful thinking'. If you could empirically demonstrate your claims had merit, my "skepticism" would be removed, and I would be happy to embrace empirical illumination and empirical wisdom.

What we have here however is a theory based on three different hypothetical entities based on a kludged together ad hoc bunch of "buddies", most recently "dark energy" which now presumably makes up 75% of the whole universe!

I'm afraid I do not see that as "finding out" anything. I see that as way to "create a mythos" that sounds pretty cool and comes with nifty math, but that is not a form of empirical truth. It requires *multiple* acts of faith on the part of the "believer".

Birkeland did things by the book. He could explain "Birkeland currents" in space and we see "cosmological examples" of such structures all the time.
http://www.universetoday.com/2006/01/12/magnetic-slinky-in-space/


It's not a "magnetic slinky, it's a "Birkeland current".

http://en.wikipedia.org/wiki/Birkeland_current

 

[edd]

You might try coming up with a *real* (physical) explanation for expansion if that is what you believe is occurring. For instance, if you are not adverse to a "subluminal" expansion driven by *external EM fields*, then I'm sure you and I could come to some agreement over time. If however you are unwilling to entertain subluminal expansion, or EM fields as the "cause" of acceleration, what can we agree on?

I don't talk about subluminal expansion for exactly the same reason I don't talk about superluminal expansion. The reason for this is hinted at by the fact that light is part of the universe that is expanding, and that the expansion rate is measured in dimensions of 1/time, not distance/time.

The problems with EU theories have been done to death. I'm not going into them again.

It didn't used to be that way. "I don't know" is a valid scientific answer.

It's certainly a better answer than giving one that is immediately demonstrably wrong. Tubbythin has put it better than me though. The right thing to do is to constantly try to explain and constantly try to disprove your explanation. Saying "I don't know" is fine (saying exactly that has been one of the most exciting points in my career) but stopping at that point is bad. We're well past the momentary "I don't know" stage with cosmic acceleration and we're working on breaking our current hypotheses.

Inflation is a different matter to LCDM (which is more about describing the universe post-inflation) and probably more difficult to test, but people are always trying to test that too, and will be testing it more as new CMB experiments and so on come online.

 

[Reality Check]

MM: Any answer to this?

What happens when the plates are such that the Casimir effect pushes the plates apart? Is this replusive force also created by a positive pressure?

Actually I asked this before and you ignored it. Here it is again.

So is this what you are saying:

• If the plates are such that the net force is replusive then the net pressure (force divided by area) is positive.
• If the plates are such that the net force is attractive then the net pressure is still positive despite the fact that the net force has changed sign.

If so your conclusion must be that the area of the plates must have also changed sign to keep the pressure positive. Can you tell us how to measure a negative area? Do we construct square plates with imaginary sides and square their imaginary lengths?

I do have another thought: Maybe you have a definition of force where it is not a vector quantity but a positive scalar quantity?

 

[Michael Mozina]

Are you tring to tell me the thing called the "Casimir pressure" is not a pressure? Seriously?

The EM field applies 'force' or pressure to the plates, sure, but it is simply kinetic energy in motion that does this "pushing", not "negative pressure in a vacuum". The difference is there are photons doing the "pushing" rather than atoms doing the "pushing", but it's all "positive kinetic energy in motion" that "pushes the plates together". There is no "negative pressure" involved, it's pure kinetic energy in motion. Seriously.

What? How can it be totally unrelated to pressure? Pressure is force divided by area. We're trying to calculate the force on a plate of a given area. How can you possibly think these things are unrelated? It even gives the final quantity as the force per unit area!

You're simply describing the "force per unit area of the carrier particle of the EM field! It is a simple "force" of nature that "pushes" (from the outside) the plates together because the "pressure" of the particles on the outside is "greater than" the "pressure" from the particles on the inside of the plates. At no time is there any "negative pressure" doing any work inside the chamber, and there cannot ever be "negative pressure" in a "vacuum" as Guth needs to make his theory fly. Even if you claim there is an EM field "pushing" on his near singularity thingy, all the arrows will be pointed directly *into* the near singularity, not "away from" the near singularity, unless of course you claiming that it is "discharging towards" some external "nearsingularitymagnetosphere" of some sort?

 

[temporalillusion]

It's a *force* (not pressure) that comes from the EM field. The "pressure" of a "vacuum" has nothing to do with the EM field.

Pressure is force per unit area. You can have pressure from atmosphere, from water, or from the vacuum. You said it yourself, the force comes from virtual particles.. those virtual particles come from the vacuum. If the pressure (yes it's pressure, because the area as important as the force in the calculation) comes from the vacuum, then the pressure of a vacuum does have something to do with the EM field.. it creates it.

I've asked before, define pressure in the sentence above. Do you mean gaseous pressure only? Or any kind of pressure at all?

Actually define vacuum as well. Do you mean a lack of matter in a region of space?

I've asked lots of questions that never get answered...

Actually that's rather more a philosophical question, akin to which interpretation of quantum mechanics you choose. The mathematics is quite clear, but whether you choose to consider it an expansion of space or a continuous process of doppler shifting is a matter more of how to interpret the equations.

What do you mean by "continuous process of doppler shifting"?

When MM talks about redshift due to doppler shift, I get the impression it's because things are actually moving away from us fast enough through non-expanding space to have the redshift that they do, which makes no sense to me because that implies we are at the center of the universe.

When you say "continuous process of doppler shifting", isn't that just another way of saying the distance between us and the source is expanding?

 

[edd]

Even if you claim there is an EM field "pushing" on his near singularity thingy, all the arrows will be pointed directly *into* the near singularity, not "away from" the near singularity, unless of course you claiming that it is "discharging towards" some external "nearsingularitymagnetosphere" of some sort?

Michael. There is no into and there is no away from.

For the rest of your post, I can see the position you are coming from but it's not correct. I can only recommend this earlier post.

You are deeply misunderstanding the theory I think, and are therefore in a poor position to criticise it.

 

[edd]

What do you mean by "continuous process of doppler shifting"?

When MM talks about redshift due to doppler shift, I get the impression it's because things are actually moving away from us fast enough through non-expanding space to have the redshift that they do, which makes no sense to me because that implies we are at the center of the universe.

When you say "continuous process of doppler shifting", isn't that just another way of saying the distance between us and the source is expanding?

Take the classic Doppler shift example of an ambulance heading away from you. The sound leaves the ambulance and arrives at you. The Doppler shift is a result of the speed of the ambulance at the time of emission (assuming you are at rest) and does not change in its journey towards you.

In the cosmological Doppler shift, the light is continually changing in wavelength from the time it is emitted until it reaches our telescopes.

That's what I mean by it being a continuous process.

 

[D'rok]

You are deeply misunderstanding the theory I think, and are therefore in a poor position to criticise it.

As a lurker obsessed with this thread, I think this is the key to the whole puzzle.

There is a credibility gap here. Whatever the discipline, in order to credibly deconstruct an established paradigm, you have to be intimately familiar with what that paradigm actually is/says/does/predicts, etc.

In other words, to be taken seriously, you have to become an expert in that which you are challenging.

 

[Michael Mozina]

My point was that you're not saying "I don't know". I'm fine with "I don't know". What I see as the antithesis of science is the "I don't know, I don't wanna know

I want to "empirically know" what, if anything created this universe just like you do. I don't want to "make up" stuff on a whim like pixies, slap on some math and "make a wild guess". Inflationdidit is no better than Goddidit at the level of empiricism as it relates to demonstrating "cause/effect" relationships.

and I'm gonna hurl abuse at anybody who tries to find out".

No but I'm going to point out to you that there is no empirical basis for your creation mythos, inflation, dark energy or SUSY particles. You didn't "find out" anything, you "made it all up" based on multiple things you cannot empirically support. Inflationdidit is not "empirical truth".

Which is pretty much how you come across (at least to me).

Well, I admit I probably do have a bit of a chip on my shoulder at this point due to the way I've seen empirical physics treated by this industry. I've seen Birkeland's empirical lab work be scoffed at for long enough now. I guess after seeing enough threads entitled "Is PC theory woo", one starts to wonder if you guys even understand the difference between empirical physics that works in a lab and "woo" that only works in myths and legends and is shy around a lab. How exactly does one decide what is "woo" other than what can be shown to work empirically and what cannot, and what can usefully predict the outcome of a physical experiment and what cannot? Inflation is pure woo because it has no useful predictive value when it comes to determining the outcome of any physical experiment. Dark energy is "woo" as well. SUSY theory is "speculative" at best, but at least we might have some hope of physically "testing" that one. None of these do anything to anything in an experiment. MDH theory works in a lab. After awhile of watching EU theory being disregarded in a callous and hostile fashion, I guess I am getting a bit "disgruntled" as it relates to your popular mythos and your industry's lack of respect for empirical physics.

 

[temporalillusion]

Take the classic Doppler shift example of an ambulance heading away from you. The sound leaves the ambulance and arrives at you. The Doppler shift is a result of the speed of the ambulance at the time of emission (assuming you are at rest) and does not change in its journey towards you.

In the cosmological Doppler shift, the light is continually changing in wavelength from the time it is emitted until it reaches our telescopes.

That's what I mean by it being a continuous process.

Right. So when you said it's a matter of interpretation of the questions, you mean that the actual process doesn't really matter right? It could be space expanding, everything shrinking, or some other mechanism that alters the light enroute, but those are just models we use to help us think about it, the math doesn't care.

Or is there some other process the math implies?

 

[Michael Mozina]

As a lurker obsessed with this thread, I think this is the key to the whole puzzle.

There is a credibility gap here. Whatever the discipline, in order to credibly deconstruct an established paradigm, you have to be intimately familiar with what that paradigm actually is/says/does/predicts, etc.

In other words, to be taken seriously, you have to become an expert in that which you are challenging.

As it relates to the Casimir force, sure.

Yet from the perspective of a skeptic it is like being told you have to become an expert on a specific religion or an expert on numerology to properly "understand the faith" well enough to critique it. Like numerology inflation theory and dark energy theory have no actually "predictive" value when it comes to predicting the outcome of a controlled experiment. How does one "test" their belief in inflation or someone's belief in God based on math? I've seen creationist whip up some math before, and this creation mythos has no more empirical support in terms of a creation date than any other creation theory. How do you take a "superluminal expansion" theory seriously? Really? Both creationism and Lambda-CMD theory *require* this to occur. Pure coincidence? Pure coincidence it was a Priest that came up with this idea? I should not be required to have "faith" in something to see it empirically demonstrated. I can experience gravity here and now. I know it exists even if I don't know the math. I can experience many real thing here and now without understanding any math. Only when it comes to numerology and inflation does one need "special math skills" to "understand" it properly. Pure coincidence?

 

[Michael Mozina]

Michael. There is no into and there is no away from.

There are VP's moving between the plates and VP's moving outside the plates and there are more of them outside the plates, creating more VP "pressure" outside the plates than inside the plates. No areas experience "negative pressure".

You are deeply misunderstanding the theory I think, and are therefore in a poor position to criticise it.

I understand *how* it actually works and I know that it in no way involved "negative pressure in a vacuum". That's how this whole debate started.

 

[Michael Mozina]

Right. So when you said it's a matter of interpretation of the questions, you mean that the actual process doesn't really matter right?

It does matter if you're actually seeking "knowledge" rather than just looking for a new way to insert some math.

 

[D'rok]

Yet from the perspective of a skeptic it is like being told you have to become an expert on a specific religion or an expert on numerology to properly "understand the faith" well enough to critique it....

And that's your consistent rhetorical trick, isn't it? Conflate science with religion and then insist that you don't have to address the claims because they are self evidently ridiculous.

I'm sorry, but it's a transparent and pathetic tactic. Turn that "scepticism" on yourself first, then take on the establishment. You are taking refuge in your ignorance. Banish your ignorance first. Otherwise, you will likely continue to be an irrelevant Internet pest whose only contribution is to entertain lurkers like me.

 

[Michael Mozina]

And that's your consistent rhetorical trick, isn't it? Conflate science with religion and then insist that you don't have to address the claims because they are self evidently ridiculous.

As it relates to something like the Casimir effect in your original statement, you are absolutely correct. I can and should understand the Casimir effect because it occurs in nature and I can study it empirically. I can and should have to address the specific claims being made.

As it relates to something like inflation however, or dark energy or dark matter in SUSY particles the math was never what I complained about so how do I "test" their idea physically?

 

[D'rok]

As it relates to something like inflation however, or dark energy or dark matter in SUSY particles the math was never what I complained about so how do I "test" their idea physically?

And that's rhetorical trick #2: "If I can't get my hands dirty in a lab, the phenomenon is self-evidently made up".

That's only slightly less transparent and pathetic than the conflation tactic. It really only demonstrates the limitations of your own technique, not the limitations of the discipline you are attacking.

Expertise first; criticism second. Or be prepared to forgo all credibility.

 

[edd]

Right. So when you said it's a matter of interpretation of the questions, you mean that the actual process doesn't really matter right? It could be space expanding, everything shrinking, or some other mechanism that alters the light enroute, but those are just models we use to help us think about it, the math doesn't care.

Or is there some other process the math implies?

I think that's a fair way to put it, yes.