To: PatrickHenry; RadioAstronomer; Physicist; ThinkPlease; Piltdown_Woman; aBootes
Alright, let's get things rolling here. You've read Guth's book, PH; what's the deal -- is dark energy, which enables an ever expanding Universe, compatible with the Inflationary model, which requires the matter density of the Universe to be the critical value; i.e., the value that would lead to a flat Geometry and a "parabolic" rate of expansion (if there were no dark energy)?
To: longshadow
You've read Guth's book, PH; what's the deal -- is dark energy, which enables an ever expanding Universe, compatible with the Inflationary model, which requires the matter density of the Universe to be the critical value; i.e., the value that would lead to a flat Geometry and a "parabolic" rate of expansion (if there were no dark energy)? Yes, I've read his book. But it predates this dark energy discovery (or surmise). Inflation is compatible with flatness, with homogeniety, smoothness, etc. All issues related to the early universe, I believe. Off hand, assuming this extra kicker to the Hubble constant is a development which occurs late in the history of the universe, I see no conflict. But I need to ponder this. If we can observe this accelerating expansion now, it's early days when it happens, isn't it? But it's after the inflationary stage, so I think Guth's work is safe. That's my preliminary take on it. (Clearly, I'm babbling, and I'm not the one to ask for an authoritative opinion.)
To: longshadow
The fascinating thing about this work is that the mysteries appear over the horizon after each major discovery.
See my post #12 about Halley, Hooke and Wrenn trying to figure out the 'unknown' inverse square force. (before Newton).
And what's happening is that our ability to gather data on a large scale is getting better.
Interesting how these things unfold. Theory plays such a dominant role versus observation in cosmology.
Hawking said in an article about 10 years ago that he was not aware of a single major theory in cosmology that was proposed as a result of observation. Observation only confirms or rejects the theory.
Yet, what has made these discoveries possible is the greatly increased ability to capture spectra at great look-back times.
To: longshadow; All
62 posted on
02/09/2003 1:46:42 AM PST by
Aracelis
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