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Talk:Essay:Quantifying Order (view source)
Revision as of 02:38, November 15, 2009
, 02:38, November 15, 2009And about that Will paper
So the Einstein prediction is within the margin of error of those four radar-ranging measurements of the Mercury anomaly. I'm sure there've been more recent studies, but I don't have them literally sitting in front of my face at the moment, so those are the ones I'm citing. Can I see your numbers that say the Einstein prediction is outside the margin? More recent data than what I have in my hand here maybe? (This Pijpers paper is [http://arxiv.org/pdf/astro-ph/9804258v1 on ARXIV], by the way, if you want to check it out.)--[[User:KSorenson|KSorenson]] 21:17, 14 November 2009 (EST)
So the Einstein prediction is within the margin of error of those four radar-ranging measurements of the Mercury anomaly. I'm sure there've been more recent studies, but I don't have them literally sitting in front of my face at the moment, so those are the ones I'm citing. Can I see your numbers that say the Einstein prediction is outside the margin? More recent data than what I have in my hand here maybe? (This Pijpers paper is [http://arxiv.org/pdf/astro-ph/9804258v1 on ARXIV], by the way, if you want to check it out.)--[[User:KSorenson|KSorenson]] 21:17, 14 November 2009 (EST)
Oh, and just incidentally? Will didn't leave Mercury out of his paper; he just talked about it in really jargony physics-paper language.
:Three decades of experiments, ranging from the standard light-deflection and perihelion-shift tests to lunar laser ranging, planetary and satellite tracking, and geophysical and astronomical observations, have placed bounds on the PPN parameters consistent with general relativity.
"PPN" is the ''parameterized post-Newton" formalism, a rewriting of the law of universal gravitation to include coefficients derived from general relativity. The Einstein field equations are nightmarish to solve, so PPN was created as a middle-ground approximation between the (good but not good enough in some contexts) Newton approximation and the agonizing pain of having to actually ''solve'' the Einstein field equations every time you want to calculate the delta-vee required during a solar slingshot maneuver for a planetary probe. What Will said in that paper is the PPN approximation has been tested ''against general relativity'' and supported by 30 years of experiments.
This is really getting into the tall grass, and I know how you hate wasting time. Maybe we can bring this conversation to a conclusion? --[[User:KSorenson|KSorenson]] 21:38, 14 November 2009 (EST)