The following are the competing mission concepts for the JDEM (Joint Dark Energy Mission) launch slot:
DESTINY also press info here
All of these make an interesting case, although how much could be done from the ground with modest HST and JWST followup is a key issue.
It'd be interesting to learn whether DoE would accept a NASA-style forced marriage on mission concepts, which has happened in the past when two groups have different strengths for mission concepts, and only one slot is open.
PS: NASA press conference on thursday - reputedly they will have tighter data points on the SNIa luminosity distance curve, showing significant acceleration at z>1
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Acceleration at z>1? The turnaround is somewhere around z=1; we're already seeing back to the era of deceleration. When I saw your link, I wondered if there was something new I hadn't heard -- but it was the same plot that has been in Adam's papers in the past (only with pretty color background).
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This announcement sounds a lot like Riess et al. paper from 2004, astro-ph/0402512. That abstract concludes: "Our constraints are consistent with the static nature of and value of w expected for a cosmological constant (i.e., wo = -1.0, dw/dz = 0), and are inconsistent with very rapid evolution of dark energy." What may be constant is change in c.
Yeah, it's not "acceleration at z > 1" -- it's "the dark energy had negative pressure at z > 1."
I presume the precise statement is some bound on W', showing that there was not any significant evolution of W, after compensating for FRW cosmological evolution.
If dW/dz > 0 by some significant amount (er, W less negative, and thus larger at higher z) then the crossover between acceleration and deceleration would have occured earlier (at higher z) since presumably the dark matter density is well constrained and evolving passively.
So the statement must be equivalent to the crossover happened at higher z than it might have given previous constraints.
From the press release: "Pinpointing supernovae in the faraway universe is similiar to watching fireflies in your back yard. All fireflies glow with about the same brightness. So, you can judge how the fireflies are distributed in your back yard by noting their comparative faintness or brightness, depending on their distance from you."
I have observed many fireflies and they do not, repeat do not glow with the same brightness. Male fireflies actually vary their luminosity to attract females. Perhaps Riess and Co. refer to fake fireflies in the Pirates of the Caribbean ride. These people are scientists?
These people are scientists?
Yes, and extremely good ones, who don't go around badmouthing those with whom they disagree.
I am happy to hear they never ignore those with whom they disagree. Since they are extremely good scientists, they will now consider that fireflies or c aren't constant.