Wikipedia:Mediation Cabal/Cases/2010-07-09/Friedmann equations

To try to subvert the [Stupid] Warning:

Editing Wikipedia:Mediation Cabal/Cases/2010-07-09

[Stupid] Warning: An automated filter has identified that the article you are trying to create/edit has a slash (/) at the end of the title. Please consider changing its name to the same title, without the slash, or moving it if it has already been created.

All I did was add this spurious text and place a few line spaces at the very top of the text. For what it was worth, I also removed the slash from the copy/pasted title.

Request details
Kentgen1 requests that JRSpriggs be replaced as the editorial reviewer of Kentgen1’s proposed editorial changes to the article “Friedmann equations”.

Where is the dispute?
Link to the article where the dispute is taking place: http://en.wikipedia.org/wiki/Friedmann_equations

Who is involved?
list of the users involved:


 * User:Kentgen1 herein called K1
 * User:JRSpriggs herein called JR

What is the dispute?
The problem:

K1 wished to insert caveats or cautionary notes to inform readers of the “Friedmann equations” (FE) that this set of formulas is only an approximate model of the universe. This fact is stated only once in the body of the text and is buried there in such a way that it is almost invisible. Also, phrasing that would seem to indicate that this particular model is the only model extant and that it is wholly and utterly valid with undisputed experimental or observational confirmation needs to be softened to allow for its hypothetical nature and for the fact that there are equally good competing views.

JR disputes K1’s contention that FE assumes the ideal gas approximation, but this is a fact that is acknowledged in the FE text itself. K1 thinks this acknowledgment is inadequate and that the overall impression that the reader will get is that the model is Gospel Truth. Or at least, it is that scientists think it is Gospel, calling it the “Standard Model”.

The Friedmann equations can be easily solved in presence of a perfect fluid with equation of state (ideal gas law) http://en.wikipedia.org/wiki/Friedmann_equations

The article then goes on to give an “equation of state” that I derived also from the ideal gas law. Except my derivation was simpler, needing only to incorporate the equation for the volume of a 3-sphere and E = mc^2 to match the article. Both derivations explicitly rely on the ideal gas assumption.

Nonetheless, the FLRW model is used as a first approximation for the evolution of the real, lumpy universe because it is simple to calculate, and models which calculate the lumpiness in the universe are added onto the FLRW models as extensions. http://en.wikipedia.org/wiki/FLRW

In his edits of the FE, K1 wishes to insert caveats concerning the metric. The use of the metric to build an approximate model like the FE requires “extensions”, a euphemism for ad hoc band-aids. Most physicists, other than cosmologists, think that the need for ad hoc postulates to fix a hypothesis is the symptom of a flawed hypothesis. That the lumpiness and some other attributes of a real universe can be thus fixed is irrelevant. The use of the flawed FE to compute parameters that lead to the conclusion of dark energy and dark matter do not make use of these fixes, and they cannot do so because we have not got the math. K1 says “Well then, get the math! Spend a few more billions of dollars on a project to develop proper mathematics!” JR, as a mathematician, should appreciate this, but he does not. He gives K1 no credit at all.

K1 wishes to insert as many cautionary notes and caveats as may be necessary to dispel the overall impression of infallibility and restore Wikipedia’s neutral tone. K1 wishes to note that the FE and the FLRW are still the subject of vigorous debate. There is no consensus and even if there were, consensus has been known to be wrong. K1 wishes to emphasize that other plausible metrics have been proposed allowing the construction of models that are just as compelling as the FE but which do not have the same implications of acceleration, dark energy and dark matter. JR ignores these points and JR’s misstatements and declaration of irrelevant demonstrably false notions proves, in K1’s opinion, that JR is hopelessly biased and incompetent to referee edits to this article.

A list of issues that need to be addressed:
JR refuses to acknowledge that K1’s claim that the Friedmann equations article contains unstated assumptions, silent postulates and hidden premises that need to be brought to light.

K1 needs to more fully document justifications for his proposed changes.

JR needs to stop focusing on minor objections to trivial details that are mentioned by K1 in TALK only to illustrate K1’s points.

And, JR must concede that K1’s main point, which is that the Friedmann equations rely on the ideal gas assumption to characterize both the substance and the metric of the universe (all matter & energy plus space-time itself), is undoubtedly true and is explicitly stated more than once elsewhere in Wikipedia.

JR should acknowledge his bias in favor of FLRW/Friedmann and the accelerating scenario of the universe’s expansion rate and the concomitant conclusion of dark energy. He must concede that all of these are still open to debate and still require skeptical analysis. Therefore, JR must recuse himself from refereeing all edits to FE.

What would you like to change about this?
[Here, tell us what you would like to be changed. Does the conversation need better structure? Are folks having difficulty communicating? Are they talking past each other? Stuff like that.]

By means of our extensive conversation it is K1’s opinion that JR is incompetent as a mathematician and as a physicist, at least in this case. He is totally biased in favor of certain conclusions that may or may not be indicated by the applied Friedmann Equations, such as dark energy and dark matter, so he defends the FE and the manner in which the article is now presented.

For instance, he states that there are no more assumptions than are given in the “Assumptions” section of the article and that there is no use of the ideal gas approximation in this mathematical model. Yet, he alludes to pressure and density of the medium comprising the universe as if these quantities can exist all by themselves with no reference to an overall “system” describable by any such “model” that contains them. He implies that pressure and density are an intrinsic part of general relativity and thus that the FE, as they are actually treated here in this particular article, are fully “derived” from Einstein’s field equations. In other words, JR contends that these Wikipedia FE are exact. JR does not seem to realize that GR itself actually presumes that space-time may be treated as an ideal fluid (which is more like a gas than anything else).

FE is exact? K1 says “No way!” and wants the article to reflect a generous degree of circumspection. JR will not accept K1’s modest changes that would accomplish a sense of tentativeness without destroying the overall structure and flavor of the article.

How do you think we can help?
[We are here to help you, but we need to know how. Sometimes mediators will look at a dispute and have no idea where to start, so please help us out. Do note that we will not "take sides" in any dispute.]

K1 and JR have different worldviews and approach problems from opposite points of view. K1 and JR are thus completely incompatible. K1 thinks JR has been deliberately obtuse in failing to recognize K1’s main issue with the FE article as it is currently written. K1’s main issue is the article’s tone of certainty and that additional references should be made to assumptions in the section on “Assumptions” and elsewhere. The Assumptions section should also include hidden premises and assumptions that are made in applying the FE and indicate in some manner the degree of risk involved in entertaining all these assumptions.

For instance, one of the stated assumptions of the FE is the Cosmological Principle. But, the CP cannot possibly be anything but a gross oversimplification that is justified only by the necessity of its use to make calculations tractable. This is stated elsewhere in Wikipedia under the FLRW metric, for example [ http://en.wikipedia.org/wiki/FLRW_metric ], which also needs revision to reflect a greater degree of tentativeness and circumspection].

JR says that CP means that the only substances in the universe are dust, gas and radiation. He avers that this can be treated without reference to any system model by using a disembodied concept of pressure and density that he says is “derived” from general relativity. But, it is not. It is derived by Friedmann from his assumptions of an ideal gas approximation by throwing in a few concepts from GR. References to pressure or density, without qualification, automatically implies the ideal gas equation anyway. And, the CP ignores the gross lumpiness in the universe, with galaxies, galactic clusters, super-clusters, structures like “the great wall” and voids that can exist on scales larger than 100 million mega-parsecs, so that the usual criteria for homogeneity and isotropism in the universe (the CP) are not really very well met. The CP is thus a huge approximation.

Furthermore, due to their dependence on the metric, the FE assume not only that the substance of the universe may be treated as an ideal gas, but that the space-time continuum itself can be included in this ideal system as if it was a local subsystem having a laboratory frame of reference. This is an enormous reach. It refers to the universe as if it was just a part of a larger system upon which it can do work and which can do work on it. Otherwise the First Law of Physics is violated: the Conservation of Matter and Energy. Now, it may well be that the universe is part of a meta-universe or a multiverse, but this has not even been begun to be proven. The hidden or implied premises underlying the FE are part of the set of assumptions that they use and they should be qualified under the Assumptions section.

Einstein wrote that general relativity almost certainly cannot be applied to the universe as a whole. But, this is what the FLRW/FE try to do. The least that we can do, as journalists, is acknowledge in the most emphatic way that we can, the risks entailed in building models that use GR like this. We must ferret out the unstated premises, the hidden postulates and ALL the assumptions, not just some select few. A lack of appreciation for these caveats is what leads Saul Perlmutter et al. and Adam Reiss et al. to promote the notion of acceleration and dark energy in the first place, which are the main reasons why the reader may be interested in the FLRW/FE anyway.

K1 wishes only to have all additional assumptions arising from the APPLICATION of the FE clearly noted and the limitations of these assumptions clearly given in the Assumptions section and elsewhere when appropriate.

K1 sought a third opinion, but it turned out that the third opinion was from within JR’s editorial circle who had actually conducted the mechanics of reverting K1’s proposed changes (JR said so). K1 thinks his or her opinion was no third opinion at all since he (or she) had an obvious conflict of interest. However, JR continued to ignore the conclusion of the 3O that K1 needs only to include more (and more precise) references and not just cite Wikipedia itself. He or she did not object to K1’s content or to his purpose of adding a modicum of circumspection to the article. [Do you know that editors are exchanging login information and are logging in disguised as one-another? Talk about disruptive behavior!]

Since JR ignores the 3O, K1 wants a new editorial reviewer. K1 thinks that JR is in love with the FE model and with dark energy & dark matter. He is incapable of objective analysis here.

Mediators need not take sides. They may simply recognize that there are irreconcilable differences between editors that require this change.

Provide diffs, if possible.
=

Revision as of 12:19, 17 June 2010 (edit) Kentgen1 (talk | contribs) (→Assumptions: a caveat that allows other interpretations of general relativity and the uses of the Cosmological Principle) ← Previous edit Revision as of 12:22, 17 June 2010 (edit) (undo) Kentgen1 (talk | contribs) (→Assumptions: additional caveat by rephrasing the last sentence) Next edit →

Line 12:	Line 12: It is not necessary to assume the Cosmological Principle or the Friedmann equations to interpret the overall behavior of the universe. Other assumptions can serve as a basis for interpreting observations. These perspectives are just as faithfull to general relativity. Many of these alternative treatments do not invoke dark energy or an accelerating universe expansion rate (see below). It is not necessary to assume the Cosmological Principle or the Friedmann equations to interpret the overall behavior of the universe. Other assumptions can serve as a basis for interpreting observations. These perspectives are just as faithfull to general relativity. Many of these alternative treatments do not invoke dark energy or an accelerating universe expansion rate (see below). -	Einstein's equations now relate the evolution of this scale factor to the pressure and energy of the matter in the universe. The resulting equations are described below. +	In Friedmann's interpretation, Einstein's equations relate the evolution of this scale factor to the pressure and energy of the matter in the universe. The resulting equations are described below. ==The equations==		==The equations==

There are a whole series of edits like this by K1 near the time of this edit that were eventually reverted. Sometimes, edits by K1 were referred to by "JR" as disruptive. What if this putative JR’s comments or reversions are even more disruptive?

This diff illustrates another matter pertaining to hidden postulates and silent premises. Friedmann takes his model in and out of the relativistic frame of reference without acknowledgement of the risk involved in mixing his metaphors. Friedmann uses the metric, which is claimed to be an exact solution to the relativity differential field equations, to compute his pretty parameters. Then he uses the ideal gas approximation to presume a pressure and density apart from the metric and apart from relativity as if it was a classical system. These flaws must be pointed out because this is not just another Wikipedia article. It is the backup for the Premier Wikipedia article on The Big Bang. It also goes straight to the heart of our concepts of cosmogony. Our concepts of who we are and where we come from are critical ideas for the survival and prosperity of our culture [Joseph Campbell].

As recommended on the dispute resolution page, one must maintain a sense of humor. I can only take JR’s messages as a sort of joke.

Mediator notes
I'm going to close this case out because I believe the requestor has a fundamental misunderstanding about how WP works. Will contact him directly on his talk page to see if I can mentor him a bit and help out. --Wgfinley (talk) 00:00, 25 July 2010 (UTC)

Discussion
I noticed some of the comments that were left with my edits before they were reverted seek to treat the FE article just like any other descriptive Wikipedia subject, implying that my edits may be somewhat out of place. The issues that I raise are far too important for this. If Wikipedia is to mention the FE and the FLRW (or even the Big Bang, for that matter) it must face these issues because this is why the reader looks to Wikipedia in the first place. Wikipedia is not and should not seek to be just another prudish, stiff and boring encyclopedia.

Kentgen1 (talk) 15:24, 10 July 2010 (UTC)

"Cosmologists are always wrong but never in doubt," said Lev Landau, the distinguished physicist and Nobel laureate.

Wikipedia must fight the tendency of cosmologists to express certainty.

Kentgen1 (talk) 14:34, 11 July 2010 (UTC)

Hello?

Kentgen1 (talk) 18:27, 16 July 2010 (UTC)