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Essay:Rebuttal to Counterexamples to Relativity (view source)
Revision as of 03:18, April 30, 2019
, 03:18, April 30, 2019Dark energy again
#:Correct me if I'm wrong, but wasn't it due to the acceleration of various parts of galaxies that accelerated funny that led to dark matter (based on simple Newtonian dynamics)?
#:Correct me if I'm wrong, but wasn't it due to the acceleration of various parts of galaxies that accelerated funny that led to dark matter (based on simple Newtonian dynamics)?
#''The acceleration in the expansion of the universe confounds Relativity, and unseen "dark energy" has been invented to try to retrofit observations to the theory.''
#''The acceleration in the expansion of the universe confounds Relativity, and unseen "dark energy" has been invented to try to retrofit observations to the theory.''
#:Relativity does not "forbid" or "permit" any particular expansion rate. The standard equations of relativity are silent on the issue of expansion, or dark matter, or dark energy. The equations were later "tweaked" with a "cosmological constant", to allow for a static universe, which was part of conventional wisdom at the time. The tweaking was abandoned when the universe was found to be expanding, much as the Newcomb-Hall tweaking of the gravity equations was found to be wrong. The cited Livescience article is not about relativity; no sensible scientist denies relativity. In fact, neither the word "relativity" nor "Einstein" appears anywhere in the article.
#:This is the dark energy/cosmological constant argument. The cosmological constant was added by Einstein after he discovered that his field equations (<math>\mathbf{G}=8\pi \mathbf{T}</math>) predicted that the universe was expanding, contradicting his firm philosophical belief in a static universe. So he inserted <math>\Lambda \mathbf{g}</math> to the LHS so that it would predict a static universe. A few years later, Hubble showed the universe to be expanding, and Einstein called the cosmological constant the worst mistake of his career. So, it sort of had a bad reputation, and people didn't want to seriously consider it, until recent observations have shown the universe's expansion to be accelerating forced them to do so. It could have had a very different history. Einstein could have had that term in the EFE's from the start, and pointed out that it would determine if the universe's expansion was accelerating (or not expanding at all!) and it would take further observation to determine its value.
#:This is the dark energy/cosmological constant argument. The cosmological constant was added by Einstein after he discovered that his field equations (<math>\mathbf{G}=8\pi \mathbf{T}</math>) predicted that the universe was expanding, contradicting his firm philosophical belief in a static universe. So he inserted <math>\Lambda \mathbf{g}</math> to the LHS so that it would predict a static universe. A few years later, Hubble showed the universe to be expanding, and Einstein called the cosmological constant the worst mistake of his career. So, it sort of had a bad reputation, and people didn't want to seriously consider it, until recent observations have shown the universe's expansion to be accelerating forced them to do so. It could have had a very different history. Einstein could have had that term in the EFE's from the start, and pointed out that it would determine if the universe's expansion was accelerating (or not expanding at all!) and it would take further observation to determine its value.
#''Increasingly precise measurements of the advance of the perihelion of Mercury show a shift greater than predicted by Relativity, well beyond the margin of error.''
#''Increasingly precise measurements of the advance of the perihelion of Mercury show a shift greater than predicted by Relativity, well beyond the margin of error.''