Date: 6/04/2013 06:30:03
From: mollwollfumble
ID: 291381
Subject: Planck CMBR - at last

Yippee!

I’ve been waiting for this for what seems like for ever, but is really only three years. This is the most important breakthrough in cosmology in the past ten years.

The Planck telescope has finally revealed the definitive map of the cosmic microwave background radiation. Immediate results include that Dark Matter makes up 26.8% of the universe, it was previously thought to be 22.7%, that’s a big difference. Now we should see final confirmation of whether Inflation is correct, and if so which version.

The press release from the Planck consortium is here:
http://www.esa.int/Our_Activities/Space_Science/Planck/Planck_reveals_an_almost_perfect_Universe

21 March 2013
Acquired by ESA’s Planck space telescope, the most detailed map ever created of the cosmic microwave background was released today revealing the existence of features that challenge the foundations of our current understanding of the Universe. Because precision of Planck’s map is so high, it also made it possible to reveal some peculiar unexplained features that may well require new physics to be understood.

The image is based on the initial 15.5 months of data from Planck and is the mission’s first all-sky picture of the oldest light in our Universe, imprinted on the sky when it was just 380 000 years old.

At that time, the young Universe was filled with a hot dense soup of interacting protons, electrons and photons at about 2700ºC. When the protons and electrons joined to form hydrogen atoms, the light was set free. As the Universe has expanded, this light today has been stretched out to microwave wavelengths, equivalent to a temperature of just 2.7 degrees above absolute zero.

This ‘cosmic microwave background’ – CMB – shows tiny temperature fluctuations that correspond to regions of slightly different densities at very early times, representing the seeds of all future structure: the stars and galaxies of today.
etc.

A major series of technical papers from the Planck consortium appeared on ArXiV on March 20 (each paper has more than 230 authors), I’ve listed them in rough order from most important to least important.

Overview http://arxiv.org/abs/1303.5062
Cosmological parameters http://arxiv.org/abs/1303.5076
CMB Power spectra http://arxiv.org/abs/1303.5075
Constraints on Inflation http://arxiv.org/abs/1303.5082
Isotropy and Statistics of the CMB http://arxiv.org/abs/1303.5083
Searches for cosmic strings and other topological defects http://arxiv.org/abs/1303.5085
Background geometry and topology of the Universe http://arxiv.org/abs/1303.5086
Constraints on primordial non-Gaussianity http://arxiv.org/abs/1303.5084
Cosmology from Sunyaev-Zeldovich http://arxiv.org/abs/1303.5080 http://arxiv.org/abs/1303.5081 http://arxiv.org/abs/1303.5089
Integrated Sachs-Wolfe effect http://arxiv.org/abs/1303.5079
Gravitational lensing http://arxiv.org/abs/1303.5077 http://arxiv.org/abs/1303.5078
Catalogue of Compact Sources http://arxiv.org/abs/1303.5088
Galactic Carbon Monoxide Emission http://arxiv.org/abs/1303.5073
Component Separation http://arxiv.org/abs/1303.5072
Constraints on peculiar velocities http://arxiv.org/abs/1303.5090
Zodiacal Emission http://arxiv.org/abs/1303.5074
Energetic particle effects http://arxiv.org/abs/1303.5071
Doppler boosting of the CMB http://arxiv.org/abs/1303.5087
High Frequency Instrument Processing, Calibration and Accuracy http://arxiv.org/abs/1303.5067, http://arxiv.org/abs/1303.5068, http://arxiv.org/abs/1303.5069
Low Frequency Instrument Calibration and Accuracy http://arxiv.org/abs/1303.5064, http://arxiv.org/abs/1303.5065, http://arxiv.org/abs/1303.5066

In addition, since 20 March there have already been a slew of new papers on the cosmic microwave background and cosmology. Including:
Confronting brane inflation with Planck and pre-Planck data
$g_{\rm NL}$ in the curvaton model constrained by PLANCK
The strongest bounds on active-sterile neutrino mixing after Planck data
Naturalness of Light Neutralino Dark Matter in pMSSM after LHC, XENON100 and Planck Data
etc.

Reading those should keep you busy for the next couple of months.

Reply Quote

Date: 6/04/2013 12:31:00
From: The Rev Dodgson
ID: 291470
Subject: re: Planck CMBR - at last

mollwollfumble said:

Now we should see final confirmation of whether Inflation is correct, and if so which version.

How does more accurate data on the CMBR allow that to be done?

Reply Quote

Date: 6/04/2013 12:40:40
From: PM 2Ring
ID: 291473
Subject: re: Planck CMBR - at last

The Rev Dodgson said:


mollwollfumble said:
Now we should see final confirmation of whether Inflation is correct, and if so which version.

How does more accurate data on the CMBR allow that to be done?

I’m not sure of the details, but it allows more accurate estimates to be made of how early after the BB inflation started and how long it lasted / how rapidly the universe inflated. The earlier inflation started, the smaller the amount of deviation. And the inflation duration / speed affects the scale: a longer inflation time / greater speed would give bigger regions of similar temperature.

Reply Quote

Date: 6/04/2013 22:05:49
From: Bubblecar
ID: 291748
Subject: re: Planck CMBR - at last

This is the only chance the universe gets to be my playground. So it had better make the most of it.

Reply Quote

Date: 7/04/2013 21:51:05
From: OCDC
ID: 292148
Subject: re: Planck CMBR - at last

>>>Immediate results include that Dark Matter makes up 26.8% of the universe, it was previously thought to be 22.7%, that’s a big difference.<<<

Not really. It isn’t going to change the patient’s management – we still don’t know what disease they have, we just know more accurately how much of it they have…

Reply Quote

Date: 9/04/2013 17:37:13
From: mollwollfumble
ID: 292873
Subject: re: Planck CMBR - at last

> How does more accurate data on the CMBR allow that to be done?

The power curve. http://commons.wikimedia.org/wiki/File:WMAP_5_year_CMB_Power_Spectra.png

In inflation models when the universe stops expanding it doesn’t stop dead. It overshoots and then overshoots backwards with ever-decreasing ripples. A ball rolling down a hill is the usual analogy, when it reaches the bottom of the hill it doesn’t stop immediately but rolls up the other side. This ends up shedding a series of ripples of different sizes into the visible universe and these can be seen as correlations of different sizes in the microwave background. Each model of inflation has its own characteristic pattern of ripples

A problem from the WMAP data was that the ripples seen were smaller than inflation models predicted, but the data had such a large error magnitude that nothing could be said for sure. One of the main purposes of Planck was to pin these ripples down with high accuracy.

Reply Quote

Date: 9/04/2013 17:49:24
From: PM 2Ring
ID: 292875
Subject: re: Planck CMBR - at last

mollwollfumble said:


In inflation models when the universe stops expanding it doesn’t stop dead. It overshoots and then overshoots backwards with ever-decreasing ripples.

Ah. Interesting.

Reply Quote

Date: 9/04/2013 17:51:26
From: Riff-in-Thyme
ID: 292876
Subject: re: Planck CMBR - at last

PM 2Ring said:


mollwollfumble said:

In inflation models when the universe stops expanding it doesn’t stop dead. It overshoots and then overshoots backwards with ever-decreasing ripples.

Ah. Interesting.

I’m still trying to find a way to imagine that.

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