BBC Focus Magazine

[M Paul Lloyd]

Horizon - 9PM BBC 2 10th March 2010. http://www.bbc.co.uk/programmes/b00rgg31
We, that is BBC Focus magazine, got a plug for this in Radio Times and yet someone with the singularly irreverent username of Toilet Sniffer V has stolen a march on us!!

There's something very odd going on in space - something that shouldn't be possible. It is as though vast swathes of the universe are being hoovered up by a vast and unseen celestial vacuum cleaner.
Sasha Kaslinsky, the scientist who discovered the phenomenon, is understandably nervous: 'It left us quite unsettled and jittery' he says, 'because this is not something we planned to find'. The accidental discovery of what is ominously being called 'dark flow' not only has implications for the destinies of large numbers of galaxies - it also means that large numbers of scientists might have to find a new way of understanding the universe.
Dark flow is the latest in a long line of phenomena that have threatened to rewrite the textbooks. Does it herald a new era of understanding, or does it simply mean that everything we know about the universe is wrong?
http://www.utdforum.com/forum/showthread.php?t=139882

Mind you, I've been saying as much for years.

[nemisis39]

Thanks for this MPL i missed it on the tv plugs for some reason and as for toiletsniffer v well there a manchester site so that would explain it all

[M Paul Lloyd]

Quite possibly Nemesis, but I could not possibly comment.

[worldmaker]

"Is Everything We Know About The Universe Wrong?"

Well, that was the theory.
But it appeared in the film that the standard model stood up, and fell down, depending on your interpretation.
So, no change. Except... for that really big vacuum cleaner?

None the wiser, really, in this reality.

[EzBloke]

I'm waiting for the scientists to catch up and start listening to dark communication...

Then they'll post their findings on a website like... the dark side?

[M Paul Lloyd]

I think they already do Ez but sadly dark communications are invisible and do not interact with the internet in the way that normal communications do. ;);)

[Merlo]

I could swear there was an article in focus a few issues back on this... still, I'd say I hope we are wrong! Our current theories still have many problems and we know we aren't right yet. However how much more can the theories be altered and still fit everything in? this would normally be the point where i stop and start again to try and get a different angle on the whole thing in light of new discoveries.

[M Paul Lloyd]

I'm with you there Merlo, time to wipe the slate clean and take a long hard look at it all.

Such as why does the universe appear to be expanding, is it a real phenomena or an optical illusion, could the microwave background just be a ghost image created by the solar systems own boundary 'shock wave' (it is suspiciously orientated to the solar axis) is the presumed age of the universe correct and is it really as young as we think it is??

[worldmaker]

Here's the interesting thought I had while watching the programme, about the effect of "dark" matter, i.e., we-can't-see-it-with-current-instruments:-

If dark matter effects the gravitational mass and rotation of a gravity, keeping all stars, even on the edge, relatively in track with a galaxy's spin, and not spinning out of control, then how come it doesn't have a comparable effect on the solar system?

If this dark mass is supposed to permeate the galaxy, it ought to permeate the solar system and have the same effect locally as it does globally?

If it doesn't then dark matter must be so thin on the ground locally that it does not effect to orbits of planets, so those farther out do have orbits slower than those close-in to the sun, but must have enough effect on the larger scale that it can effect the galaxy, the relationships between the stars and bind the galaxy together as a fairly single mass (the galaxy does have a little drag in the out arms sweeping behind the core spin).

So "dark matter" permeates the entire galaxy, does it float freely beyond solar systems, within the galaxy? Does it take the form of a force without material, is the moon really made of cheese?

At this point something went pop in my head.

They're trying to look for dark matter inside the solar system, but it might not exist inside the system?
I think I need to build my starship to go looking.

[M Paul Lloyd]

You make a valid point there Worldmaker, personally I think they are chasing shadows.

[nemisis39]

You make a valid point there Worldmaker, personally I think they are chasing shadows.

ahhhh right so its as i susected dark matter is shadders fault quick get running the men in dark suits are coming or is that MIB

If dark matter is invisable then how do they know its there other than the gravity theory could be something totally diffrent that is having this cause and effect haven't got a clue what though

[M Paul Lloyd]

Well if an orbital system is perceived to be further from view than it actually is it will appear to be moving more quickly than one that is close at hand.

For example.
Consider a binary system consisting of particles w and p at distance q from an observer k. The path of particle w covers an orbital path x around p at distance y from particle p and time for w to complete an orbit x of p is b seconds but b seconds is too short a time to complete distance y at distance x, it is in effect moving too fast, making the total mass of w and p too little to maintain the orbit therefore mass/gravity of w and p system must be greater, but observed size of p and w is anomalous to observed velocity/gravity calculations, ergo more mass is required to hold said system together and so dark matter gets invented to plug the gap.

But, if said system is closer at hand, as in distance to q from observer k is less, so distance y and thus distance x are smaller thus w and p can complete orbital distance y in time b seconds for observed mass of w and p.
This means that if the universe is smaller than observed then you don't need dark matter.

Plus if the universe isn't expanding (and redshift is just an optical illusion) you don't need dark energy either. Simple, but it works

[M Paul Lloyd]

Is no-one going to rise to the challenge?

[Shadowwolf]

Simple, but it works

Simple perhaps, but you would actually have to prove this to be the case over the current model where redshift does not appear to be an illusion.

[Merlo]

Doesn't redshift show that everything in the universe is moving away from everything else? Depending on the nature of the shape of the universe, it does not mean it's expanding (I could be catastrophically wrong here, but bear with me ). For example suppose the universe has always been the same size but 'dimensions' have been increasing... it's a hard concept to explain. :S

[M Paul Lloyd]

Red shift purports to show that everything in the universe is moving apart at an accelerated rate because ever more distant objects display an increased shift in their respective light towards the red end of the spectrum.

However if this is merely an optical illusion caused by some as yet undetermined effect (these objects are a hell of a long way off) then we can stop worrying about what is seemingly both pushing the universe apart on the grand scale and yet pulling it all together on a medium scale but is apparently totally absent in local space................... and well it just doesn't make sense to me.

It's all a bit reminiscent of poor old Aristarchus of Samos who in around the third century BC pointed out that the motion of the Sun and Planets in the nights sky could be so easily explained if only the sun were at the centre and not the Earth. Everyone else said he was a fool because it was so obvious that if the earth was going around the Sun then we would all fall off and sadly he was unable convince them because as Mr.S points out it needs to be proved which took around 1,400 years.

I'll keep working at it.

[Shadowwolf]

Well unless I am very much mistaken, redshift has been demonstrated experimentally as a result of a receding light source. So we know that it does happen due to a light source moving away from us, hence why redshifted cosmic sources are taken to be moving away from us.

Now there may yet be another explanation for why we have redshift in the case of cosmic sources but crucially, until we have evidence of another explanation then there is none. Ifs and possible optical illusions may make a given system more simple, but they amount to nothing more than arbitrary speculation, and so lacking evidence they can be dismissed when there is a supported explanation available. We must be mindful not to let preference cloud the evidence that exists in favour of that which has — perhaps only currently — none. Now one might contend that to just accept what is may lead to a wrong assumption never being overturned, which is possible I suppose. But if one is going to overturn a given explanation then one must endeavour to provide support for the alternative, speculation is just an assertion, possibilities but no reason to drop the current reasoning on a subject.

[M Paul Lloyd]

Good point Mr.S red shift is real and a good example of the Doppler effect, but I am far from convinced that it is necessarily what we are observing in distant objects, that is just conjecture based upon observation, we do not actually have proof as such.

[M Paul Lloyd]

You see I do wonder what stuff like this would have on a hundred millions years worth of light beaming its way to Earth.
http://news.bbc.co.uk/1/hi/sci/tech/8571418.stm

[Shadowwolf]

Good point Mr.S red shift is real and a good example of the Doppler effect, but I am far from convinced that it is necessarily what we are observing in distant objects, that is just conjecture based upon observation, we do not actually have proof as such.

But it is a valid conjecture, the effect is real so it is very reasonable to suggest that the reason we get redshift in cosmic light sources is because they are moving away. Redshift is not just used for galactic observation but along with blueshift, has been used to ascertain the velocity and mass of local galactic stars. The proof you speak of if I understand correctly is currently impossible in galactic terms and may be so for quite some time if not for ever, that being a probe in another galaxy getting further away as measured by some other factor than light. To realistically reject motion as the cause of the observed redshift there must be some other explanation that fits the observations as well or better and has evidence, otherwise the rejection is a matter of personal taste and not science.

You see I do wonder what stuff like this would have on a hundred millions years worth of light beaming its way to Earth.

Whilst this may seem like an initial problem, perhaps the source of the 'illusion' of redshift it really does not present much of an obstacle as far as I can see. For dust to be an issue it would have to be homogeneous in all directions beyond the galaxy, and remain so regardless of the motion of galaxies or gravity's tendency to pull matter together. Furthermore moving dust clouds within our galaxy would create wildly changing redshifts of local stars and sources beyond, wildly variable readings would have been noted and the tool dropped In respect of local observation it would require an amazing coincidence of sufficient quantities of dust getting in and out of the way in order to provide the illusion locally. In respect of far off galactic observations, as far as I am aware there is no correlation of high redshift, hence distant with concentration of known dust lanes. The apparently furthest away should be in certain regions which is not the case, and if I understand it correctly some stars should appear as if they are a long, long ways off. So with — or perhaps because of — my limited understanding it would appear that dust cannot be the cause of redshift and is insufficient cause to dismiss what redshift appears to be showing.