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

ben m said:

MM has absolutely no idea what "negative pressure" even refers to. He seems to think it's invalid because by definition it requires negative energy. I now have no idea what he has learned, failed to learn, or is deliberately ignoring from the past 1000 posts.

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My current speculative hypothesis: Michael has no understanding of calculus and, as such, doesn't realise that dU/dV can be negative without either U or V being negative.

Cosmological Constant II

One more reference for the cosmological constant: The Cosmological Constant by Sean Carroll, from Living Reviews in Relativity, a free access online journal.

Michael Mozina said:

It's only your insertion of a metaphysical entity into that term that I ultimately object to, not the presence of the term itself.

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OK. You tell us: What is the physical reality of the cosmological constant? What is it really?

Zeuzzz said:

I
Nothing went bang.

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Still the same straw, how wonderful of you. Explained many times and you still revert to lies, deception and straw.

Nothing went bang is correct becuase that is NOT the thery.

"The universe appears to be expanding."
"We can not say what existed prior to the BBE or is outside the universe."

Those are the theroy.

Not your usual lies and mis-characterizations.

Zeuzzz said:

You having trouble with the words? spelling? grammer? I can help.

If you having trouble with the meaning then you need to explain why.

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I will make it easy for you:

You are full of ****. You are deluded, pretend a lot and haven't a clue. For years you have misrepresented every time you tried to present manistream science.

You can't handle the real math or science, three years ago you were still quoting pop science arcticles that had been debunked by COBE.

When asked to do the work and provide the evidence you resorted to pouting and gradstand arm waving.

You still haven't retracted your agnosticism of the nuclear fusion in stars.

Now you present some sort of philosophy and pretend that it is meaningful.

Zueuus you are sooo full of ****:

Your article presents the same BOGUS strawmen as suaul, but since you just spam and run, you are not aware that every point in it has already been addressed in the threda.

Well done sir! You are full of **** as usual.

Geoffrey Burbidge, eminent physicist and professor emeritus of the University of California San Diego, is one of many highly respected cosmologists who have questioned the validity of the big bang model and has pointed out many of its shortcomings: "there have been very few real predictions;" for example, "while the black body nature of the radiation was predicted by the big bang theory, the numerical value of the temperature was not, and cannot be" (Burbidge, 2006, p. 5).

Further, some scientists have taken umbrage at the willingness of BB modelers to embrace ad hoc assumptions as a means of patching over gaps in the "standard model" such as the inability to explain why most of the universe appears to be missing. For example, as critiqued by Burbidge (2006) BB theorists have resorted to hypothesizing the existence of invisible "dark matter" and "dark energy" to account for the 95% of mass-energy that is "missing," given BB assumptions. These assumptions, however, are then used to support yet other BB related theories such as current "scenarios" proposed for galaxy formation, which in turn "rests on this belief that this missing mass is real, because only if [cold, dark matter] exists in large measure is it possible to simulate galaxy formation at all" (Burbidge, 2006, p. 6).

The prevailing focus on assimilation and confirmation can also become problematic when transitions are made to even stronger claims. Clowe et al. (2006) for example, claim to have found "proof" of "dark matter," based on their interpretation of data from a galaxy collision. The Clowe et al. paper features some impressive technical arguments and then fails to consider a number of important and very critical caveats. In particular, the argument assumes that normal matter is fully accounted for by an inventory of visible stars and hot plasmas. However, it has been reported that non-visible interstellar gas, lower-energy plasmas and brown dwarfs, in combination, likely exceed luminous stars in the estimated mass of the nearby portion of our galaxy (e.g., Fuchs, Jahreiss, and Flynn, 2006). As summed up by philosopher of science James Hall, "Our hypotheses may get support or they may go down in flames, but they never, ever get proved" (Hall, 2005).

The same can be said of interpretations of the so-called Cosmic Microwave Background radiation (CMB). Because of its cool temperature, the BB modelers claim the CMB is conclusive evidence of cooling after a very hot beginning. However, the CMB could be due to a number of causes, including the burning of hydrogen.

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:ld:

Dark Matter: Direct Detection?

Michael Mozina said:

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.

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Mozina posted this thinking that the discovery of these ultra faint dwarf galaxies and star clusters provides good evidence that dark matter is entirely baryonic. But, as I showed in Dark Matter and Ultra Faint Dwarf Galaxies, back on page 30 (a post to which Mozina never responded), in fact the discovery of new ultra faint dwarfs solves a major problem with dark matter cosmology, and so tends to confirm rather than falsify the theory of non-baryonic dark matter.

I have already shown elsewhere that the astronomical evidence in favor of the non-baryonic dark matter hypothesis is significant (e.g., Galaxy Rotation & Dark Matter, Dark Matter II, Dark Matter and Science). Is there now also evidence from ground based experiments?

The DAMA project (including DAMA/NaI and DAMA/LIBRA) has produced results that are consistent with the laboratory detection of elusive non-baryonic dark matter particles. These results are reported in two recent papers:

1. First results from DAMA/LIBRA and the combined results with DAMA/NaI;
   Barnabei, et al., The European Physical Journal C 56: 333, August 2008
2. New results from DAMA/LIBRA
   Bernabei, et al., Feb 2010; presented at the Int. Conf. Beyond the Standard Models of Particle Physics, Cosmology and Astrophysics (BEYOND 2010), 1-6 February 2010, Cape Town, South Africa.

Drukier, et al., 1986 and Freese, et al, 1988 predict an annual periodicity in dark matter particle detection for Earth based experiments, independent from particular models of particle properties, simply due to the motion of Earth. Of course, since the year is a rather natural periodicity to see on Earth based experiments, one must be careful to avoid confusing our own seasons with dark matter. Nevertheless, this can be done, by identifying a set of simultaneous criteria which must be met, in order to be certain that the signal detected is the signal desired.

This has been done and the predicted annual signal has been reported. Bernabei, et al., 2000 report the detection of this annual signal at a 4-sigma confidence level, using data from the DAMA/NaI experiment, cycles 1-4 combined. Bernabei, et al., 2008, Bernabei, et al., 2009 & Bernabei, et al., 2010 report continued detection of the same cycle with the DAMA/LIBRA experiment which is an extension of the DAMA/NaI experiment. The new data are sufficient to support the detection at the 8.2-sigma confidence level, a much more robust result than had been reported earlier. Finkbeiner, Lin & Weiner, 2009 discuss the significance of the DAMA/LIBRA results. In particular, we note that other experiments, using different methods, do not detect this signal, and an explanation is required. Is the DAMA/LIBRA signal wrong? Or maybe the DAMA/LIBRA signal can be used to constrain dark matter particle properties. There are papers which address this issue (e.g., Feldstein, et al., 2009; Angle, et al., 2009; Ahmed, et al., 2009; Foot, 2008). Bernabei, et al., 2009 and Bernarbei, et al., 2008 describe the apparatus & technical details of carrying on the DAMA/LIBRA search for dark matter.

These papers and the many citations thereto should provide quite a sufficient field of exploration. For now, suffice to say that there are Earth based experiments at work looking towards direct detection of non-baryonic dark matter particles, to go along with extensive astronomical & astrophysical evidence. Against this robust package of observational & experimental data, along with a robust package of theoretical & practical physics (e.g, general relativity, classical mechanics, thermodynamics & electromagnetism), the best Mozina can do is rattle on about "metaphysical entities", without the offer of even a tiny sliver of anything recognizable as real science or real physics. It's time to face the music: The Mozina argument against the existence of non-baryonic dark matter is dead.

Note that I make no claim the non-baryonic dark matter must exist. But I do make the explicit claim that the data are consistent with the existence of non-baryonic dark matter, in the context of a completely valid exercise of science. There are of course numerous groups studying the obvious alternative of modified gravity. But it is the consensus of the community that the dark matter hypothesis is the simpler solution to the original "missing mass" problem. If the implications of the DAMA/LIBRA experiment stand up, it will add strong support to the non-baryonic dark matter hypothesis over the modified gravity hypothesis.

Tim Thompson said:

OK. You tell us: What is the physical reality of the cosmological constant? What is it really?

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It could be many things. I don't profess to have an "explanation". How about you tell me why you think it has anything to do with "dark energy"?

I'm still waiting for the "Genesis" chapter here before I can actually comment. I want to hear what your mass thingy was made of, was it "charged" in any way? What was it's physical size? Was anything "outside" the mass object? Where does the "vacuum" concept play into anything? Where does dark energy and inflation fit into this mythical legend?

So far you've all been extremely coy when it comes to laying out a real "theory", complete with details about size, charge, vacuum pressures, the relevance of inflation theory, etc. I don't even know if you all share the same "beliefs' about these things in until I hear some details.

ben m said:

So let's go through again:

MM has absolutely no idea what "negative pressure" even refers to.

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Not when you're applying it to a "vacuum" I do not. Come now Ben, stop being so coy. How large was your mass object before "inflation"? Where as inflation, inside or outside of the mass thingy? Was it charged in some way that might produce a "negative pressure" on the outside surface of the object? What exactly do you mean by "negative pressure" and how and where does it factor into anything? Be specific and lay out your genesis chapter.

ben m said:

Yet you also said that the "CC in the EFE gives acceleration, matter in GR gives deceleration" is correct, and you apparently agreed with all of the signs in a gas-vs-Casimir comparison. In both cases, whatever else is going on, the vacuum has the opposite dU/dV of an ordinary gas. Ordinary gases have positive pressure. Vacuum energy has the opposite.

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The only "vacuum energy" that might put "negative pressure" on a full spherical surface would be the EM field if your surface was charged in some way. More mass (like a spherical mass covering) on the "outside" of your mass thing might also produce "negative pressure" on the surface of the entire sphere. A "vacuum" can only ever contain "positive pressure" however, so by itself, it can never "suck" Guth's mass thingy apart. In a non charged scenario, all the 'pressure' form the QM fields would push *INTO* not away from the surface of his mass body.

I'm going to kick back now and go grab a beer and watch the game. Since I'm not betting on today's game, I going to hope the Saints win. Go Saints.

Michael Mozina said:

Not when you're applying it to a "vacuum" I do not. Come now Ben, stop being so coy. How large was your mass object before "inflation"? Where as inflation, inside or outside of the mass thingy? Was it charged in some way that might produce a "negative pressure" on the outside surface of the object? What exactly do you mean by "negative pressure" and how and where does it factor into anything? Be specific and lay out your genesis chapter.

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When we apply it to a vacuum then it produces negative pressure.

The rest of your post is dumb so I will respond in a similiar vein
From your gibberish I can extract one coherent question, "What exactly do you mean by negative pressure".
The answer is exactly what is in all of the physics textbooks that you have never read.
The answer is exactly what all the posters have been telling you for many years, over many forums, in many threads and many posts.

The answer is exactly what you have not been able to comprehend for many years, over many forums, in many threads and many posts.

• When pressure is defined as dF/dA then negative pressure is the result when there is an attractive force on a surface.
  This happens in the Casimir effect.
• When the more general defintion of pressure = -dE/dV is used then negative pressure is any time that dE/dV is positive.
  This happens for a positive value of the cosmological constant (and in the Casimir effect!).

Michael Mozina said:

Not when you're applying it to a "vacuum" I do not.

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Which sign, then, did I get wrong in the calculation of dU/dV in a positive-energy-density vacuum?

(ETA: I and Sol and RC and TT and Einstein and Lemaitre and Zeldovich and Witten and Perlmutter and Guth and ... )
(ETA2: Do you, in fact, understand that for any function f(x), the derivative df/dx can be either positive or negative, independent of whether f(x) is positive or negative?)

Michael Mozina said:

In a non charged scenario, all the 'pressure' form the QM fields would push *INTO* not away from the surface of his mass body.

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Except that we're not looking at kinetic pressure pushing on things. For the 11th time: we're looking at an energy density, and energy densities cause gravitational curvature. The vacuum energy density is positive, remember? The resulting curvature (according to 1915 GR, remember?) causes outward acceleration, remember? Positive vacuum energy (a hypothesis) causes (according to GR) outward acceleration, remember? That's what matters.

The reason you're unable to picture this based on "sucking" and "pushing" is that this has nothing to do with it.

The only reason we use the word pressure is that this behaves the same way as negative pressure in any actual equation dealing with the energetics of pressure. We do not call it "pressure" for the sake of your mental picture of a gas-like substance filling the vacuum, because this picture is nonsense.

As for Michael's "coy" comment: the mainstream theory is laid out explicitly in any mainstream astro textbook whatsoever---Peebles, Weinberg, Peacock, Dodelson, Wald, Misner-Thorne-Wheeler, etc. It's laid out in half of the links we've posted, like Sean Carroll's "living reviews" article. NASA spends literally millions of dollars developing educational materials about exactly this theory. There are probably ten thousand papers on the topic, both in broad overviews and in any detail you could possibly want to look into, in the refereed literature.

"Coy" my foot. The words you're looking for are "La la la la I can't hear anything."

Dark Energy is a Cosmological Constant III

Michael Mozina said:

It could be many things. I don't profess to have an "explanation". How about you tell me why you think it has anything to do with "dark energy"?

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Analytical Considerations About the Cosmological Constant and Dark Energy
Abreu, de Assis & Dos Reis; International Journal of Modern Physics A 24(28-29): 5427-5444 (2009)
Abstract (emphasis mine):
"The accelerated expansion of the universe has now been confirmed by several independent observations including those of high redshift type Ia supernovae, and the cosmic microwave background combined with the large scale structure of the universe. Another way of presenting this kinematic property of the universe is to postulate the existence of a new and exotic entity, with negative pressure, the dark energy (DE). In spite of observationally well established, no single theoretical model provides an entirely compelling framework within which cosmic acceleration or DE can be understood. At present all existing observational data are in agreement with the simplest possibility that the cosmological constant be a candidate for DE. This case is internally self-consistent and noncontradictory. The extreme smallness of the cosmological constant expressed in either Planck, or even atomic units means only that its origin is not related to strong, electromagnetic, and weak interactions. Although in this case DE reduces to only a single fundamental constant we still have no derivation from any underlying quantum field theory for its small value. From the principles of quantum cosmologies, for example, it is possible to obtain the reason for an inverse-square law for the cosmological constant with no conflict with observations. Despite the fact that this general expression is well known, in this work we introduce families of analytical solutions for the scale factor different from the current literature. The knowledge of the scale factor behavior might shed some light on these questions mentioned above since the entire evolution of a homogeneous isotropic universe is contained in the scale factor. We use different parameters for these solutions and with these parameters we establish a connection with the equation of state for different DE scenarios."

There are of course many papers one can reference which present the detailed analysis which support the claim made in the above abstract , that "At present all existing observational data are in agreement with the simplest possibility that the cosmological constant be a candidate for DE. This case is internally self-consistent and noncontradictory" (e.g., Serra, et al., 2009; Kowalski, et al., 2008; Frieman, Turner & Huterer, 2008; Guzzo, et al., 2008; Wood-Vasey, et al., 2007; Davis, et al., 2007; Astier, 2006 & etc., including the original papers Riess, et al., 1998 & Perlmutter, et al., 1999).

Carroll, Press & Turner, 1992 offer a complete review of the cosmological constant in a paper published well before the discovery of the accelerated expansion of the universe in 1998. It was only after this discovery that cosmologists perceived the need for dark energy and realized that it came most simply in the form of a cosmological constant. Peebles & Ratra, 2003 and Carroll, 2001 offer complete reviews of the cosmological constant in papers published after it had become associated with the new concept of dark energy.

Keep an eye on my real point here. There are other possible explanations for dark energy including modified gravity, a scalar field in the stress-energy tensor, or even a time variable cosmological scalar field instead of a cosmological constant. The current state of observational data cannot rule out any of these possibilities. I am only insisting that the identification of the cosmological constant is both consistent with the observational data and the simplest (i.e., least complicated) source of dark energy, given the current state of observation.

Michael Mozina said:

I'm still waiting for the "Genesis" chapter here before I can actually comment. I want to hear what your mass thingy was made of, was it "charged" in any way? What was it's physical size? Was anything "outside" the mass object? Where does the "vacuum" concept play into anything? Where does dark energy and inflation fit into this mythical legend?

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I have no idea what you are talking about. What is "mass thingy" supposed to mean? And why are any of these questions supposed to be relevant at all? We need only interpret observed cosmological redshifts as an indication that the universe is expanding, and the acceleration of that expansion becomes an observed phenomenon. dark energy is simply a kinematic explanation for the observed phenomenon. I fail to see why anything you have said here nas anything to do with that.

Michael Mozina said:

So far you've all been extremely coy when it comes to laying out a real "theory", complete with details about size, charge, vacuum pressures, the relevance of inflation theory, etc. I don't even know if you all share the same "beliefs' about these things in until I hear some details.

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What "theory" are you talking about? So far we have all been far less "coy" that you have. You would not even admit to having any idea what the cosmological constant is supposed to be, despite insisting that you think it is absolutely necessary for general relativity to be a complete theory. If anybody is being "coy" around here it is definitely you, the man who never has produced a quantitative explanation of anything, and can't even produce qualitative explanations without running afoul of the laws of physics big time.

What known type of "energy" possesses "negative pressure"?

Why is "negative pressure" necessary for expansion of matter if the sun manages to do it everyday with known forces of nature?

Michael Mozina said:

What known type of "energy" possesses "negative pressure"?

Why is "negative pressure" necessary for expansion of matter if the sun manages to do it everyday with known forces of nature?

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So what you're saying is that after over a thousand posts in this thread you still don't understand the concept of negative pressure. Got it.

schrodingasdawg said:

I'm going to admit confusion on this point. (It's actually something that's confused me for a while; hopefully someone here can help me.) Isn't the cosmological constant term a different term than the stress-energy tensor?

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It's part of it. Or to be a little more precise, one can consistently regard it as part of it.

If it was part of the ordinary energy/pressure density, then why would it need a separate term?

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It doesn't.

I can elaborate on that if you tell me what types of terms you're wondering about (in the action? in the stress tensor itself? in Einstein's equations?).

And isn't it (in the context of GR, anyway) supposed to be constant over all space and time--i.e. intrinsic to the geometry of spacetime?

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It's supposed to be constant over all space and time, yes. In the stress tensor, that means that its pressure is minus its energy.

Whether you think that means it's "intrinsic to the geometry of spacetime" is more or less up to you. Quantum vacuum energies have those features, but the magnitude and sign of the resulting cosmological constant depends on the spectrum of fields as well as the background geometry. To me, that doesn't sound very intrinsic.

Michael Mozina said:

What known type of "energy" possesses "negative pressure"?

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You have a 1000-post thread explaining why "negative pressure" is the normal and expected behavior of vacuum energy. Before we repeat it again, why don't you summarize what you think the mainstream view is?

Why is "negative pressure" necessary for expansion of matter if the sun manages to do it everyday with known forces of nature?

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Because those forces do not act strongly over long distances or on charge-neutral objects. (ETA: as you know from the previous 10 times you've made exactly the same claim.) (ETA2: and gravity IS a known force of nature. Dark energy is not a new force, it's an energy density, and all energy densities pull on spacetime in a straightforward way. As you know from the previous 10 etc etc.)

GeeMack said:

Michael Mozina said:

What known type of "energy" possesses "negative pressure"?

Why is "negative pressure" necessary for expansion of matter if the sun manages to do it everyday with known forces of nature?

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So what you're saying is that after over a thousand posts in this thread you still don't understand the concept of negative pressure. Got it.

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MMs' cognitive disconnect is much, much deeper than that.

You see, tens of thousands of posts, by MM, make it abundantly clear that he has no grasp of what "quantitative" means, with respect to physics.

For example, gravity is "a known force of nature" because, in MM's view, a plasma ball purchased from Tesco falls when you let it go. Now MM seems to accept that gravity, as a known force of nature, can also produce apparently non-falling behaviour, like the plasma ball rising to the surface if submerged in a bath of water (or mercury), or can slingshot a spacecraft around Jupiter and out of the solar system ... but he does not understand why these things happen (beyond some intellect-lite word salad).

As a result, when it comes to seemingly counter-intuitive things like negative pressure or the cosmological constant as dark energy, he rejects them blindly.

But! There needs to be an intellectual figleaf for this irrational, emotional response, some sort of narrative that papers over the disturbing contradictions bubbling just beneath the surface.

And what is that security blanket? "Empirical tests", as in "done in a lab, here on Earth". That this prop is riddled with internal inconsistencies is not a problem for MM, because they can be transformed away by waving the 'qualitative' wand over them (no lab experiment has shown that two atoms attract each other gravitationally? no worries! two atoms, 10^23 atoms, they're all just atoms!).

Unless and until MM owns up to his outright rejection of two the key elements of modern physics - its quantitative nature, and its requirement for internal consistency - 1000-page threads will continue to grow like weeds in your garden.