Goodbye accelerated expansion:

http://phys.org/news/2016-10-universe-rateor.html

Looks like all those prizes were for spurious data from a data set one tenth the size of what we have now. With the larger data set, the reading goes down to 3 sigma. Oops.

I am just slightly relieved; don't mind dark matter but never liked dark energy.
I hope dark energy is eventually proven definitely false.

Originally posted by sonhouse
http://phys.org/news/2016-10-universe-rateor.html

Looks like all those prizes were for spurious data from a data set one tenth the size of what we have now. With the larger data set, the reading goes down to 3 sigma. Oops.

If I read that right, it still points at expansion, just not as strongly.
https://en.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_rule

Originally posted by twhitehead
If I read that right, it still points at expansion, just not as strongly.
https://en.wikipedia.org/wiki/68%E2%80%9395%E2%80%9399.7_rule

But they are expanding the data points so in a few years the expansion may go away completely. I wonder if there is going to be analysis that shows it all bogus when they factor in the new galaxies found, they think up to a trillion galaxies now not the couple hundred billion they thought were there before. That has to upset the ordinary matter V dark matter ratio. Maybe.

Originally posted by sonhouse
But they are expanding the data points so in a few years the expansion may go away completely.

True, but it hasn't yet gone away. Its not as if they have suddenly found evidence that there isn't any acceleration. Instead, they have found less evidence that there is. They have gone from being say 99.99999% certain to only 99.9% certain.

Of course given that it is all based on only one particular observation (by which I mean a particular type of observation), one should not put overmuch faith in it.

I wonder if there is going to be analysis that shows it all bogus when they factor in the new galaxies found, they think up to a trillion galaxies now not the couple hundred billion they thought were there before. That has to upset the ordinary matter V dark matter ratio. Maybe.
As always, you should always qualify such figures with 'observable universe' an not treat that figure as a total in the whole universe. It amazes me how often people get that wrong.
I also note that that figure is not based on actual observation, but a mathematical model that probably still needs to be verified, double-checked and in a few years may turn out to be only 2 sigma. 🙂

Originally posted by twhitehead
True, but it hasn't yet gone away. Its not as if they have suddenly found evidence that there isn't any acceleration. Instead, they have found less evidence that there is. They have gone from being say 99.99999% certain to only 99.9% certain.

Of course given that it is all based on only one particular observation (by which I mean a particular type of o ...[text shortened]... till needs to be verified, double-checked and in a few years may turn out to be only 2 sigma. 🙂

I thought it would be obvious it was the observable universe since it was Hubble and other telescopes that spotted them.

Maybe larger data sets will show several expansion events, an expansion followed by a not-so expansion era and another expansion or some variation on that theme.

If shown to be true, it may not even come from dark energy but some more subtle property of our universe we know nothing about yet. Dark energy is just something they poured into the bucket of unknowns to try to account for the effect, which at this point is only hypothesis.

Originally posted by sonhouse
If shown to be true, it may not even come from dark energy but some more subtle property of our universe we know nothing about yet. Dark energy is just something they poured into the bucket of unknowns to try to account for the effect, which at this point is only hypothesis.

Which is why its called 'dark'. Essentially we don't know what it is but energy of some kind is the best fit for the equations at present.

Originally posted by twhitehead
Which is why its called 'dark'. Essentially we don't know what it is but energy of some kind is the best fit for the equations at present.

Well, for a long long time gravity was also thought to be a force till Einstein changed that view.

It could be some kind of gravity field but not energy per se.

Originally posted by twhitehead...They have gone from being say 99.99999% certain to only 99.9% certain. ...

Or they've gone from being say 0.1% certain to only 0.00001% certain. I mean, as long as we're just making up statistics on the internet. Bet I'm closer.

Originally posted by apathist
Or they've gone from being say 0.1% certain to only 0.00001% certain. I mean, as long as we're just making up statistics on the internet. Bet I'm closer.

You would loose that bet. I am 99.999999% certain that you would loose it. 🙂

Hint: you are the only one making up statistics on the internet.

Originally posted by twhitehead
You would loose that bet. I am 99.999999% certain that you would loose it. 🙂

Hint: you are the only one making up statistics on the internet.

Is that 6 or 7 Sigma you are certain?