Horizon tonight - is everything we know about the universe..

[Rum]

Horizon on BBC2 tonight alert. Entitled 'Is everything we know about the Universe wrong'. Blurb talks about 'dark flow' (new to me!).

Should be worth a watch!

[Gawdzilla Sama]

"dark flow" was mentioned in the latest SciAm. It' kicked in my fright-or-flight reflex and I moved on to the Shermer column.

[AshtonBlack]

If they harp on about string and superstring theories as if they are proven/tested then I will throw a track.


(Just noticed, harp... fuck, I'm unconsciously punning. I will give myself a warning.... or I would do if that were technically possible.)

[Gawdzilla Sama]

If they harp on about string and superstring theories as if they are proven/tested then I will throw a track.


(Just noticed, harp... fuck, I'm unconsciously punning. I have given myself a warning.)

You mean like when you wake up next to a strange woman with a lump in your throat and a string hanging out of your mouth?

[AshtonBlack]

If they harp on about string and superstring theories as if they are proven/tested then I will throw a track.


(Just noticed, harp... fuck, I'm unconsciously punning. I have given myself a warning.)

You mean like when you wake up next to a strange woman with a lump in your throat and a string hanging out of your mouth?

During her "dark flow" time?

[RuleBritannia]

Dark flow is a name given to a net motion of galaxy clusters with respect to the cosmic microwave background radiation which was found in a 2008 study. According to standard cosmological models, the motion of galaxy clusters with respect to the cosmic microwave background should be randomly distributed in all directions. However, analyzing the three-year WMAP data using the kinematic Sunyaev-Zel'dovich effect, the authors of the study found evidence of a common motion of at least 600 km/s toward a 20-degree patch of sky between the constellations of Centaurus and Vela.

The authors suggest that the motion may be a remnant of the influence of no-longer-visible regions of the universe prior to inflation. Telescopes cannot see events earlier than about 380,000 years after the creation of the universe, when the universe became transparent (the Cosmic Microwave Background); this corresponds to the particle horizon at a distance of about 46 billion (4.6×1010) light years. Since the matter causing the net motion in this proposal is outside this range, it would in a certain sense be outside our visible universe; however, it would still be in our past light cone.

The results appear in the October 20, 2008, issue of Astrophysical Journal Letters, which is available online. The authors state that they plan to extend their analysis to additional clusters and the recently released WMAP five-year data.

Astrophysicist Ned Wright posted an online response to the study arguing that its methods are flawed. The authors of the "dark flow" study released a statement in return, refuting three of Wright's five arguments and identifying the remaining two as a typo and a technicality that do not affect the measurements and their interpretation.

A more recent statistical work done by Ryan Keisler claims to rule out the possibility that the dark flow is a physical phenomenon because Kashlinsky et al. do not consider primary CMB anisotropies as important as they are.

[AshtonBlack]

So the intergalactic equivalent of dark matter for the early post inflationary universe?