Damage Control! Damage Control!
in [Relativity]
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From: Rock Brentwood on 14 Jun 2010 18:08 On Jun 14, 3:40 pm, Uncle Al <Uncle...(a)hate.spam.net> wrote: > > All cosmologists on deck! > > Limber up your arms. > > Heat up lots of fudge. > > Paradigm on fire! > "The reasons for the difference between the radio source and the > Jupiter beam profiles are therefore still unclear." > 1) Jupiter is neihter a point source nor a broad sky source. > 2) Bob, enjoy a well-earned retirement while demonstrably better > minds think original thoughts. The press reporting in the site needs improvement. In an adjoining article, the columnist reports that so-and-so posits (expotential) inflation all the way back to time 0 -- a mathematical impossibility. What this actually describes would be a hyperbolic cosine (which is, BTW, one of the large number of possible solutions in the presence of a real or effective cosmological "constant"). In contrast, an expotential entails an infinite time tail and there would be no time 0 (also a possible solution, BTW). In another of the adjoining articles "Cosmologists Predict a Static Universe in 3 Trillion Years" -- the oft-repeated statement is made that late in a De Sitter expansion all the other galaxies will have "moved too far away to see". This is Newtonian thinking -- note the tacit reference to simultaeneity. The correct statement is this: at later points in time, the size of the cosmological horizon INCREASES, which means more and more galaxies' worldlines come into the past light cone -- not less. What ACTUALLY changes is that they appear to be further away and more red- shifted. But there's more of them that come within view, not less; since the past light cone at event X contains the past light coens of al events Y that lie to the past of X Therefore, timelike worldlines that intersect Y's past light cone must intersect X's past light cone; so all worldlines visible at Y are visible at X (albeit with greater red shift). This, of course, is excluding worldlines that end abruptly in singularities.
From: Androcles on 14 Jun 2010 18:23 "Rock Brentwood" <markwh04(a)yahoo.com> wrote in message news:4fd1cbe7-fd69-454c-9298-b4a3352c67b6(a)c33g2000yqm.googlegroups.com... On Jun 14, 3:40 pm, Uncle Al <Uncle...(a)hate.spam.net> wrote: > > All cosmologists on deck! > > Limber up your arms. > > Heat up lots of fudge. > > Paradigm on fire! > "The reasons for the difference between the radio source and the > Jupiter beam profiles are therefore still unclear." > 1) Jupiter is neihter a point source nor a broad sky source. > 2) Bob, enjoy a well-earned retirement while demonstrably better > minds think original thoughts. The press reporting in the site needs improvement. In an adjoining article, the columnist reports that so-and-so posits (expotential) inflation all the way back to time 0 -- a mathematical impossibility. What this actually describes would be a hyperbolic cosine (which is, BTW, one of the large number of possible solutions in the presence of a real or effective cosmological "constant"). In contrast, an expotential ================================================ The word you've entered isn't in the dictionary. Click on a spelling suggestion below or try again using the search bar above. 1.. exploitation 2.. exceptionally 3.. exceptional 4.. exploitative 5.. exceptionable ================================================ entails an infinite time tail and there would be no time 0 (also a possible solution, BTW). In another of the adjoining articles "Cosmologists Predict a Static Universe in 3 Trillion Years" -- the oft-repeated statement is made that late in a De Sitter expansion all the other galaxies will have "moved too far away to see". This is Newtonian thinking -- note the tacit reference to simultaeneity. The correct statement is this: at later points in time, the size of the cosmological horizon INCREASES, which means more and more galaxies' worldlines come into the past light cone -- not less. What ACTUALLY changes is that they appear to be further away and more red- shifted. But there's more of them that come within view, not less; since the past light cone at event X contains the past light coens of al events Y that lie to the past of X Therefore, timelike worldlines that intersect Y's past light cone must intersect X's past light cone; so all worldlines visible at Y are visible at X (albeit with greater red shift). This, of course, is excluding worldlines that end abruptly in singularities. ======================================= Gotta love those expotentials that end abruptly in asymptotes.
From: eric gisse on 14 Jun 2010 19:19 Robert L. Oldershaw wrote: > > Just when you thought your cosmological assumptions were rock solid... > > http://www.sciencedaily.com/releases/2010/06/100613212708.htm > > http://arxiv.org/PS_cache/arxiv/pdf/0912/0912.0524v2.pdf The conclusions of the sciencedaily article are hyperbole compared to what the technical paper _actually says_. I know - I know - reading literature is for elitists, but I find that knowing what you are talking about helps. Assuming that the results are true, then all that is done is that error bars on WMAP data get a bit wider. BFD. > > All cosmologists on deck! > Limber up your arms. > Heat up lots of fudge. > Paradigm on fire! You didn't even read the paper. Find a new hobby.
From: eric gisse on 14 Jun 2010 19:28 Rock Brentwood wrote: > On Jun 14, 3:40 pm, Uncle Al <Uncle...(a)hate.spam.net> wrote: >> > All cosmologists on deck! >> > Limber up your arms. >> > Heat up lots of fudge. >> > Paradigm on fire! >> "The reasons for the difference between the radio source and the >> Jupiter beam profiles are therefore still unclear." >> 1) Jupiter is neihter a point source nor a broad sky source. >> 2) Bob, enjoy a well-earned retirement while demonstrably better >> minds think original thoughts. > > The press reporting in the site needs improvement. No, it needs to be deleted entirely. The article discussed two entirely different things (WMAP systematics, integrated Sachs-Wolfe effect) as if they were the same. Sawangit wrote a paper that was published in April's MNRAS about the ISW effect. The ISW effect was not found, but only at something like a 1 sigma confidence level. [...]
From: Sue... on 14 Jun 2010 19:51
On Jun 14, 12:58 pm, "Robert L. Oldershaw" <rlolders...(a)amherst.edu> wrote: > Just when you thought your cosmological assumptions were rock solid... > http://www.sciencedaily.com/releases/2010/06/100613212708.htm > > http://arxiv.org/PS_cache/arxiv/pdf/0912/0912.0524v2.pdf > > All cosmologists on deck! > Limber up your arms. > Heat up lots of fudge. > Paradigm on fire! I Need More Dilithium Crystals, Captain! --Scotty http://en.wikipedia.org/wiki/Induced_gravity Sue... |