Talk:Quintessence (physics)

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[edit] What Cosmological Constant?

I assume what is meant is that with a fixed value w would be a cosmological constant. Doesn't that contradict the role in the observed accelerating expansion though? Article could use some attention. Lycurgus 00:47, 30 May 2007 (UTC)

Einstein's general relativity (GR) assumes his Cosmological Constant(CC) - a specific nomber in GR - has w = -1 everywhere and everywhen. Quintessence (Q) sets w = -1/3 to match observational data supporting accelerating expansion. The distinction between the two is that,in Q, vacuum pressure and density(proportionately) decrease with time as the universe expands. Both theories maintain a constant lightspeed. Other theories, under development, assume lightspeed increases when pressure (i.e. vacuum energy density, a.k.a. Zero Point Field density) decreases. C. Lee Robins, physicist. 66.59.230.158 15:51, 16 September 2007 (UTC)

[edit] Quintessence vs. Inflation

Hi, is there anyone who could explain what the difference is between quintessence and inflation? This might be of interest for this article.
René 20.32 (CET), 15 June 2007

Quintessence is a modification to Einstein's General Relativity which seeks to explain an observed increase in the rate at which the universe is expanding/inflating. (This increasing rate is not predicted by GR) C. Lee Robins, physicist 66.59.230.158 15:46, 16 September 2007 (UTC)

Well, yes, this is the meaning of quintessence, but what about inflation? Inflation is a scalar field which has caused an accelerated expansion in the early ages of the universe, as quintessence currently does. However, quintessence and inflation are different, but what exactly is the difference?
René 20.46 (CET), 01 October 2007 —Preceding unsigned comment added by 62.227.255.237 (talk) 18:48, 1 October 2007 (UTC)