Split Thread Michael Mozina's thread on Dark Matter, Inflation and Cosmology

[Michael Mozina]

http://arxiv.org/abs/1002.0504

FYI, they found some more of that "missing mass" in our own galaxy, and oh ya, it's "baryonic material" we just never identified until now, not some new and exotic type of mass. Get used to that scenario. It's happens a lot and it's going to keep happening.

 

[schrodingasdawg]

This seems like an appropriate time to mention the genetic fallacy. The genetic fallacy is a faulty leap of reasoning where a conclusion is based on the origin of something, even if this origin is not necessarily relevant to the discussion at hand.

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

An example of the genetic fallacy would be: "Einstein introduced the cosmological constant to make a static universe model. Therefore, a cosmological constant can only result in a static, not an expanding, universe." Indeed, Einstein's reason for introducing the term is irrelevant; GR works with the constant anyway, and its empirically measured value does not depend on why Einstein introduced it.

 

[Tubbythin]

And therein lies the problem......

You can put as many "."'s in your statement as you want. It doesn't stop the issues I brought up in my previous post being issues. 29 orders of magnitude is rather a lot you know. Its roughly the same scale factor as a distance that is ten times the distance to the Andromeda galaxy to the separation of the plates. Do you understand the problem yet?

 

[Tubbythin]

http://arxiv.org/abs/1002.0504

FYI, they found some more of that "missing mass" in our own galaxy, and oh ya, it's "baryonic material" we just never identified until now, not some new and exotic type of mass. Get used to that scenario. It's happens a lot and it's going to keep happening.

Well, let's see:

All three objects have a similar size (~ 3 pc), luminosity MV ~ −1 and con-
tain only a few tens of stars.

Let's assume, for the sake of argument, that the few tens of stars from each of the objects total 100 solar masses (seems reasonable to me as an order of magnitude calculation). The missing mass in our galaxy is ~ 10¹¹ solar masses. So that means we only need to make another billion such discoveries to account for dark matter . Interesting though the discovery is, its utterly irrelevant for dark matter considerations.
Note also that the authors don't mention the words "dark" or "matter" once in the article.

ETA: OOPS, that serves me right for just reading the abstract and conclusion. One of the discoveries is only a few tens of stars. The other is much bigger.
So...errr... what ben_m said further down.
ETA2: Or maybe not. Aaargh!

 

[Perpetual Student]

I think it's more than a little unfair to refer to an artists drawing or rendition as a "cartoon". Both diagrams correctly demonstrate the EM forces from the perspective of QM. Sometimes a drawing can give a lot more accurate information than an oversimplified math formula PS!

But it is merely a cartoon like image!
Is a diagram of the solar system proof of the heliocentric theory? If so, geocentric diagrams would be proof of a geocentric universe. You image means nothing; it's only an image attempting to demonstrate his/her perspective of some aspect of the Casimir effect. As many have already stated, there is no definition of the blue bubbles! What do they mean? Are they virtual particles? Regions of space-time? Wave packets? How could such an ambiguous cartoon be evidence of anything in your mind?

 

[ben m]

Get used to that scenario. It's happens a lot and it's going to keep happening.

Another loop around the Great Circle of Repetition. Yes, we're going to keep finding baryonic matter until it adds up to 4% of the total mass of the Universe. The BBN and CMB data tell us that the total is 4%, but telescopes have only directly located 2-3%, mostly in the ICM. We're NOT going to find matter that adds up to 25%---it is utterly impossible to hide any known form of matter (not gas, plasma, dust, rocks, planetoids, planets, compact stars, dwarf stars, normal stars, big stars, black holes, IMBHs, or SMBHs) in galaxies or clusters in those amounts.

Again, this is the Nth time I've posted exactly this. But here you're back with another mindless post of the same hidden-baryonic-dark-matter idea. Did you forget how we ruled that idea out? What's next? Tomorrow you'll be claiming it's all rocks (again)? The next day you'll be claiming it's Perratt's magnetic forces (again)?

As for the paper you cited: sure, there are hard-to-find subdwarf galaxies. We've known for decades that they ought to exist and we've been looking for them very hard; there are a dozen or so of them. (I could tell you why they are so interesting, but I doubt you will understand.) We expect that there are 100+ smaller ones as well. These newly-found satellites probably weigh something in the ballpark of 10^7 solar masses, or 0.003% of the mass of the Milky Way. I suspect that you, MM, will fail to appreciate that number, but others will.

 

[ben m]

Another loop around the Great Circle of Repetition. Yes, we're going to keep finding baryonic matter until it adds up to 4% of the total mass of the Universe. The BBN and CMB data tell us that the total is 4%, but telescopes have only directly located 2-3%, mostly in the ICM. We're NOT going to find matter that adds up to 25%---it is utterly impossible to hide any known form of matter (not gas, plasma, dust, rocks, planetoids, planets, compact stars, dwarf stars, normal stars, big stars, black holes, IMBHs, or SMBHs) in galaxies or clusters in those amounts.

Again, this is the Nth time I've posted exactly this. But here you're back with another mindless post of the same hidden-baryonic-dark-matter idea. Did you forget how we ruled that idea out? What's next? Tomorrow you'll be claiming it's all rocks (again)? The next day you'll be claiming it's Perratt's magnetic forces (again)?

As for the paper you cited: sure, there are hard-to-find subdwarf galaxies. We've known for decades that they ought to exist and we've been looking for them very hard; there are a dozen or so of them. (I could tell you why they are so interesting, but I doubt you will understand.) We expect that there are 100+ smaller ones as well. These newly-found satellites probably weigh something in the ballpark of 10^7 solar masses, or 0.003% of the mass of the Milky Way. I suspect that you, MM, will fail to appreciate that number, but others will.

ETA: wait a sec, Tubbythin is closer to correct. 10^7 Msun is the typical mass of things like Fornax, SagDEG, etc.. The new ones are a factor of 1000 smaller in volume and so, yeah, probably only ~1000 solar masses. Galaxy-wise, these little guys count for 0.0000003% each.

 

[Michael Mozina]

This seems like an appropriate time to mention the genetic fallacy. The genetic fallacy is a faulty leap of reasoning where a conclusion is based on the origin of something, even if this origin is not necessarily relevant to the discussion at hand.

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

An example of the genetic fallacy would be: "Einstein introduced the cosmological constant to make a static universe model. Therefore, a cosmological constant can only result in a static, not an expanding, universe." Indeed, Einstein's reason for introducing the term is irrelevant; GR works with the constant anyway, and its empirically measured value does not depend on why Einstein introduced it.

Awhile back in the thread I noted that I had some sympathy for sol's position in the sense that Einstein himself introduced that constant into GR, and thereby opened up Pandora's box for all the metaphysical junk that his now being stuffed into an otherwise elegant empirical theory.

Einstein never really tried to explain the nature of that constant, and in fact his sole purpose for using it went out the window with Hubble's findings and he set it back to zero (or the Hubble constant) again and left it that way for the remainder of his life.

Now if you folks would like to reintroduce such a constant, you still have the burden of proof to describe and explain what that term physically relates to in terms of actual empirical physics. The "Hubble constant" isn't an "empirical explanation" of that constant, it's simply an "observation".

Another big time fallacy in play here is that expansion and/or acceleration have anything to do with "dark energy". Dark energy never caused a single atom to accelerate, so it can't possibly have anything to do with GR.

Now if you want to stuff MHD formulas into what was once "NOTHING" in Einstein's description of GR, I'm open to that idea. Why? Because in that case you're using another known force of nature that does have a known effect on at least "some" forms of matter. On the other hand, stuffing formulas about "invisible magic energy" in there isn't going to fly.

 

[ben m]

http://arxiv.org/abs/1002.0504

FYI, they found some more of that "missing mass" in our own galaxy, and oh ya, it's "baryonic material" we just never identified until now, not some new and exotic type of mass. Get used to that scenario. It's happens a lot and it's going to keep happening.

I just want to ask---despairing of the answer: we spent several pages talking about the "missing mass", how we know about it, why mainstream astronomers have ruled out baryonic dark matter.

Do you remember this discussion at all? You appeared to be reading it and posting in it. It included a simple calculation on my part of what the Milky Way would look like if the "dark matter" were made of X, Y, Z.

Would you care to summarize what you learned from that discussion? Would you care to summarize what you think we were trying to tell you, whether or not you agree with it?

With that in mind: is your posting of this dwarf-galaxy paper meant to ignore my calculations, to tell me my calculations were wrong, or to raise a case where my calculations do not apply? Or was this posting meant to be a Harry Frankfurt contribution?

 

[Michael Mozina]

But it is merely a cartoon like image!

Lot's of scientific drawings look "cartoon-like". That does not detract from their scientific accuracy! Come on. There isn't just one of them, there are actually two of them. The "arrow" drawing is more of a pure QM EM oriented depiction of force. The "blue foam" depiction is also a QM depiction of "pressure" (on both sides) from the "quantum foam" oriented viewpoint of QM. Both are entirely valid, and entirely accurate depictions of what is going on at the level of actual physics.

The "math formula" is a grossly oversimplified formula that relates to *one* side of the plate, and is *RELATIVE* to the "pressure' on the other side of the plate. Sometimes the math formula can be more "cartoonishly oversimplified", and therefore be entirely misleading. That's exactly what's going on here.

As many have already stated, there is no definition of the blue bubbles! What do they mean?

I already provided a WIKI link to the notion of quantum foam. That is what those blue bubbles represent at the level of QM.

Are they virtual particles?

Some brands of QM describe them that way, yes. Notice they exist on both sides of both plates and are "larger" on the outside than the inside.

Regions of space-time? Wave packets? How could such an ambiguous cartoon be evidence of anything in your mind?

The math formula is the real "cartoon". It's a "relative" depiction of pressure on one side of the plate. The drawings are actually much more "accurate" in terms of describing the physical processes responsible for the Casimir effect.

They show the *PRESSURE* on *ALL SIDES* of all plate, and make it clear that the minus sign is a "relative" number.

 

[Michael Mozina]

You can put as many "."'s in your statement as you want. It doesn't stop the issues I brought up in my previous post being issues. 29 orders of magnitude is rather a lot you know. Its roughly the same scale factor as a distance that is ten times the distance to the Andromeda galaxy to the separation of the plates. Do you understand the problem yet?

What does that have to do with either diagram?

 

[schrodingasdawg]

Could you explain what you mean by "empirical explanation"?

The purpose of physics is to provide a mathematical phenomenology of nature. It builds models and tests those models' predictions against measurement. That is what is meant by physics being an empirical science.

Naturally, physicists being humans who are interested in what's "really going on", delve sometimes into a bit of metaphysics. Lorentz believed that there was a luminiferous ether, and frames at rest with respect to it were at "absolute rest"; however, the ether transformed in such a way that it was impossible to detect this absolute rest frame by any experiment. So Lorentz' belief was metaphysical, not physical. The way that reference frames transform in special relativity is a physical model, and can be empirically tested.

A model of an expanding universe with a cosmological constant is a physical model. The expansion rate and expansion acceleration rate (and thus cosmological constant) are empirically measured. The relevant model, with its values for the Hubble and cosmological constant is, in fact, an empirical explanation for the observed cosmology. It don't require a metaphysical explanation (i.e. "Why are these constants equal to what they are? Why is this model true?")--at least not in the eyes of physics.

It would seem to me that by "empirical explanation", you mean "metaphysical explanation", which is not necessary.

(Oh, and before you say it--"dark energy" is not meant to be a metaphysical explanation of anything. It is a blanket term used for a component of a class of cosmological models.)

 

[Perpetual Student]

MM does make a good point that Einstein introduced his CC to avoid instabilities in GR that would lead to a collapsing universe. After Hubble's discoveries he abandoned it and called it his "biggest blunder."

As far as I know, the CC has since been a matter of debate related to questions about the ultimate fate of the universe (e.g.: continuing to expand eternally, ceasing to expand, ultimately collapsing) . So re-introducing it as a way to explain cosmological acceleration would be a new application. I believe this is a fairly accurate summary of the history of the CC. Can anyone demonstrate otherwise?

 

[Tubbythin]

Awhile back in the thread I noted that I had some sympathy for sol's position in the sense that Einstein himself introduced that constant into GR, and thereby opened up Pandora's box for all the metaphysical junk that his now being stuffed into an otherwise elegant empirical theory.

You seem to have utterly ignored the point beingmade in the post you were responding to.

Einstein never really tried to explain the nature of that constant, and in fact his sole purpose for using it went out the window with Hubble's findings and he set it back to zero again and left it that way for the remainder of his life.

Now if you folks would like to reintroduce such a constant, you still have the burden of proof to describe and explain what that term physically relates to in terms of actual empirical physics.

What does that even mean? Can you explain what "G" is? Or can you just measure it?

The "Hubble constant" isn't an "empirical explanation" of that constant, it's simply an "observation".

You do like your double quotes don't you. Unfortunately it makes your sentences completely meaningless.

Another big time fallacy in play here is that expansion and/or acceleration have anything to do with "dark energy".

Dark energy is the name given to a class of theories that could explain the cause of the acceleration. Dark energy thus has everything to do with the acceleration of the expansion.

Dark energy never caused a single atom to accelerate, so it can't possibly have anything to do with GR.

And I supposed you've measured the acceleration due to gravity of one atom due to another. If not, then by the exact same reasoning that you have just used, we must reject G as having anything to do with GR. So, let's see it.

Now if you want to stuff MHD formulas into what was once "NOTHING" in Einstein's description of GR, I'm open to that idea. Why? Because in that case you're using another known force of nature that does have a known effect on at least "some" forms of matter.

Yes, it has a known effect which bears no resemblance to the observed effect. Hell, I have a new theory, the expansion of the Universe is caused by a BaByliss hairdryer. That uses a known force of nature to accelerate stuff. Who cares what the stuff is or whether the numbers work?

On the other hand, stuffing formulas about "invisible magic energy" in there isn't going to fly.

Michael, why do you keep putting your own words in quotes? Its very weird.

 

[ben m]

Now if you folks would like to reintroduce such a constant, you still have the burden of proof to describe and explain what that term physically relates to in terms of actual empirical physics. The "Hubble constant" isn't an "empirical explanation" of that constant, it's simply an "observation".

First: the burden of proof is on us to write down the correct equations-of-motion for the Universe. The equations-of-motion for the Universe are, according to direct observations of those motions, the Einstein Field Equation for an infinite, homogeneous Universe with rho = 0.25 and lambda=0.75. Period. All of your claims that this equation doesn't work are utter baloney. It's an equation of motion, and we can see the motion.

Second: there's a second burden, an unrelated one, to figure out what makes rho=0.25 and what makes lambda=0.75. For the former, we count up all the stars, gas, and dark matter and add up their masses and this tells us that rho=0.25. For the latter: lambda=0.75 is probably the sum of energies of lots of quantum vacuum fluctuations, but the exact theory is still unknown. We're working on it.

Now if you want to stuff MHD formulas into what was once "NOTHING" in Einstein's description of GR, I'm open to that idea.

I did this already, repeatedly, in the previous cycle of samsara. It tells you that electromagnetism and plasma physics makes a negligible contribution to anything on large scales. Did you forget? Ignore? Think you found a loophole? Solved it yourself?

 

[Tubbythin]

What does that have to do with either diagram?

Are you asking what relevance it is that what you are claiming and reality differ by a factor of a hundred thousand million million million million?

 

[Tubbythin]

Lot's of scientific drawings look "cartoon-like". That does not detract from their scientific accuracy! Come on. There isn't just one of them, there are actually two of them. The "arrow" drawing is more of a pure QM EM oriented depiction of force. The "blue foam" depiction is also a QM depiction of "pressure" (on both sides) from the "quantum foam" oriented viewpoint of QM. Both are entirely valid, and entirely accurate depictions of what is going on at the level of actual physics.

The "math formula" is a grossly oversimplified formula that relates to *one* side of the plate, and is *RELATIVE* to the "pressure' on the other side of the plate. Sometimes the math formula can be more "cartoonishly oversimplified", and therefore be entirely misleading. That's exactly what's going on here.



I already provided a WIKI link to the notion of quantum foam. That is what those blue bubbles represent at the level of QM.



Some brands of QM describe them that way, yes. Notice they exist on both sides of both plates and are "larger" on the outside than the inside.


The math formula is the real "cartoon". It's a "relative" depiction of pressure on one side of the plate. The drawings are actually much more "accurate" in terms of describing the physical processes responsible for the Casimir effect.

They show the *PRESSURE* on *ALL SIDES* of all plate, and make it clear that the minus sign is a "relative" number.

Wow. Wow. Wow.
This HAS to be a parody.

 

[Michael Mozina]

How could such an ambiguous cartoon be evidence of anything in your mind?

Try looking at it the other way around. How could an ambiguous minus sign in a "cartoon-like" depiction of "pressure" be evidence of anything in your mind?

 

[Michael Mozina]

Wow. Wow. Wow.
This HAS to be a parody.

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

No, it's QM.

 

[Michael Mozina]

Are you asking what relevance it is that what you are claiming and reality differ by a factor of a hundred thousand million million million million?

What are you talking about? The only thing that "differs" between us as far as I know is the notion of "relative" vs. "absolute" pressure.