New survey casts doubt on supernova evidence for Dark Energy

In article ,
Yousuf Khan writes:
Well, before there was Dark Energy, there was a model that fit the data
too. That was the hot Dark Matter model, where the place of Dark Energy
was filled by neutrinos.

By "before," you mean pre-COBE? There are a lot of new data since
then.

If future data disagree with current models, the models will have to
change. That's how science works.

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On Wednesday, November 2, 2016 at 5:31:44 AM UTC-7, Jeff-Relf.Me wrote:
You still have to explain why the expansion doesn't=20
slow down due to the gravity of everything it contains. =20

Expansion does slow down because of gravity. That's put into the
equations via Omega_M. See Ned Wright's cosmology calculator
http://www.astro.ucla.edu/~wright/CosmoCalc.html
and its tutorial and glossary.

In article ,
dlzc writes:
Saying Dark Energy, something that is uniformly distributed across
the Universe at each epoch, and yet varies with time (at least
between the Big Bang Event and now), isn't a model I can wrap my
head around, yet.

Nobody knows what Dark Energy is or whether it varies in time. There
are now upper limits on time variation, but that should be measured
much better in the next several years, so stay tuned. If Dark Energy
is a cosmological constant, it won't vary with time (in proper
coordinates). If it is something else, then it might vary.

It's also conceivable that Dark Energy could vary with position, but
I doubt details will be worked out until there's a serious chance of
observing that possibility. Or maybe the working out has been done
but not publicized because of the difficulty of observational tests.

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Help keep our newsgroup healthy; please don't feed the trolls.
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On 11/7/2016 5:43 PM, Steve Willner wrote:
In article ,
Yousuf Khan writes:
Well, before there was Dark Energy, there was a model that fit the data
too. That was the hot Dark Matter model, where the place of Dark Energy
was filled by neutrinos.

By "before," you mean pre-COBE? There are a lot of new data since
then.

If future data disagree with current models, the models will have to
change. That's how science works.

No, not pre-COBE, COBE data was already around, supernova data came
around later, and then they changed the interpretation of COBE & WMAP
data to fit the Dark Energy hypothesis.

Yousuf Khan