@drrogera You're going to ASCB, I take it?

mrgunn: @drrogera You're going to ASCB, I take it?

See original: Twitter @drrogera You're going to ASCB, I take it?

@drrogera That's @LabSpaces, not me. Mine was a while back.

mrgunn: @drrogera That's @LabSpaces, not me. Mine was a while back.

See original: Twitter @drrogera That's @LabSpaces, not me. Mine was a while back.

WOOHOO!!! Time to sedate that eye by systemic admin of EtOH ;-) RT @LabSpaces: I PASSED MY DEFENSE :) Thanks for all of the support guys!

mrgunn: WOOHOO!!! Time to sedate that eye by systemic admin of EtOH ;-) RT @LabSpaces: I PASSED MY DEFENSE :) Thanks for all of the support guys!

See original: Twitter WOOHOO!!! Time to sedate that eye by systemic admin of EtOH ;-) RT @LabSpaces: I PASSED MY DEFENSE :) Thanks for all of the support guys!

@communicating Thought you might have. I guess there are tons of small obvious things, depending on your perspective.

mrgunn: @communicating Thought you might have. I guess there are tons of small obvious things, depending on your perspective.

See original: Twitter @communicating Thought you might have. I guess there are tons of small obvious things, depending on your perspective.

Dark Energy: Beyond Supernovae (Part 4) [Starts With A Bang]

Follow humbly wherever and to whatever abyss Nature leads, or you shall learn nothing. -T.H. Huxley

We've spent a little bit of time talking about dark energy, including what we think of it, how we first discovered it, and how we knew that there wasn't just something out there blocking the light. It seems to be the latest abyss that Nature is leading us, so we needed to look beyond the type Ia supernova data and see what else the Universe was telling us.

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(Image credit: Don Dixon.) So what do we do? First off, we can try to measure how much matter is in the Universe independent of anything else. How do we do this? We use the most accurate method available, of course. This means taking giant surveys of galaxies and clusters of galaxies, combined with a knowledge of gravity.

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(Image credit: the 2dF galaxy redshift survey team.) Then you take this actual clustering data and you compare it with simulations of Universes with different matter compositions. You take a Universe with 10% matter, then you take another one with 20%, 30%, 40%, etc., and see which one matches the Universe you actually have in front of you.

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(Image credit: Millenium Simulation.) From clustering data, we can tell that the Universe has somewhere between 25 and 30% of its energy in the form of normal matter. Independent of any supernova data, we learn that most of the energy in the Universe is not normal matter.

So what's the rest of it? We need the cosmic microwave background to tell us that.

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(Image credit: WMAP team.) These tiny little fluctuations tell us a tremendous amount about what's in our Universe. Moreover, they tell us whether space in the Universe is curved positively like a sphere, flat like a sheet of paper, or curved negatively like a saddle.

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These three different curvature cases would lead to the hot and cold spots looking different from one another, and the differences are striking. BOOMERANG was able to tell these cases apart.

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Only the middle case -- a flat Universe -- holds up to the data. In fact, the limits are that if the Universe is curved, the amount of curvature is less than 2% of the total energy density. So we have not only supernovae, but clusters of galaxies and the cosmic microwave background too, all pointing towards the same Universe. One where it's spatially flat, full of about 25-30% matter, and where the remaining 70-75% is some mysterious form of energy. Seriously, all these different data sets point towards the same conclusion:

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The Universe is mostly full of dark energy, which would need to exist even without the supernova data! It's a very unusual thing for all of these different sources of data to come in all at once, like they have over the past decade, and all support the same conclusion.

But this is what we've got, and it's supported from every angle. So take Huxley's advice, and follow Nature into the abyss of dark energy, or -- the horror -- you shall learn nothing.

Read the comments on this post...

Also check out the featured ScienceBlog of the week: Applied Statistics

See original: ScienceBlogs Select Dark Energy: Beyond Supernovae (Part 4) [Starts With A Bang]

Pierre Lindenbaum: Where Does My Money Go?

Pierre Lindenbaum
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Our aim is to promote transparency and citizen engagement through the analysis and visualisation of information about UK public spending. - Pierre Lindenbaum

See original: FriendFeed - search Pierre Lindenbaum: Where Does My Money Go?

Nanotechnology in 24 seconds/7 words, courtesy of Wade Adams and the Ig Nobels

How do you describe nanotechnology in 24 seconds, or even in 7 words?  Tough challenge, but Professor Wade Adams, Director of the Richard E. Smalley Institute for Nanoscale Science & Technology at Rice University rose to it with aplomb at this year's Ig Nobel awards.
Here's the transcript of the achievement, ...

See original: 2020 Science Nanotechnology in 24 seconds/7 words, courtesy of Wade Adams and the Ig Nobels

¡Hazte oír! - Roland Emmerich

(ES) ¡Haz una pregunta en el debate en directo organizado por CNN/YouTube! Envía aquí tus preguntas y vota a tus favoritas hasta el 14 de diciembre.
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See original: Uploads by Cop15 ¡Hazte oír! - Roland Emmerich

Who dat!! RT @whatwereeating: off to run errands before the saints game starts! who dat!

mrgunn: Who dat!! RT @whatwereeating: off to run errands before the saints game starts! who dat!

See original: Twitter Who dat!! RT @whatwereeating: off to run errands before the saints game starts! who dat!