View Full Version here: : What is in a void?
14-12-2010, 10:26 AM
Observations indicate there by present vast regions of space where there seems to be nothing. Called "voids" I think one has a size of some 500 million light years approx diameter.
My question is ...do "they" consider these regions as entirely devoid of all matter... not even a single H atom in these regions and only the energy that passes by as it traverses these void regions? Have these regions formed immediately after the big bang or were they formed over years as galaxies formed?
14-12-2010, 10:33 AM
Space isn't ever truly empty.
Even a small area of space still has photons passing through it.
Space itself has energy … a very small amount ..but there's a lot of space .. so there's a lot of energy out there.
A true vacuum is impossible to achieve (or measure).
My 2 cents worth. (All reasonably justifiable opinions, mind you ;) )
14-12-2010, 10:48 AM
Your two cents worth I value much higher Craig:thumbsup:.
I spend a lot of time thinking about nothing:eyepop:... what one may find in nothing. I always conclude there can be no such item as nothing so I find these voids very interesting but as they are our best nothing to date little more is said..as what can be said about nothing?
I think it would be reasonable to expect that even in nothing there must be a great deal of something..even in a void the energy passing thru must be considerable even if we limit each galaxy to contributing only one photon per minute to the flow of energy one starts to wonder how even such a small number could "fit" into nothing.
I guess when I think of nothing I find it hard to throw out the term "aether" as it is difficult to visualize an absence of energy or even in other regions of space a presence of particles passing by...
I wonder how the higgs field may operate in, or if indeed it would exist in a void.
Thank you Craig for your meaningful input:thanx:.
14-12-2010, 10:57 PM
Well, you won't find the letter "e"...
(This is a very literary "in" joke. I'll wait to see who picks it up...)
Nice to see you back, Alex.
15-12-2010, 12:08 AM
I don't think this term means a void in the same sense as a physicist may use it but it indicates a zone with very low counts of galaxies. One of the most notable is the Bootes void that spans about 200 million light-years that (appears) to contain just 100-odd galaxies.
If you look at plots of the 2df and 6df data gathered at Siding Spring (some here)
you can see the large-scale structure of the Universe -- it looks like a sponge or soap-suds. The galaxies are, by and large gathered around the edges of bubbles of low galaxy density -- the voids. Some are bigger than others, the Bootes one is very large and quite empty -- of galaxies at least. There is also very little raw galaxy/star building material (H, He) as well.
15-12-2010, 08:53 AM
Thanks Brian:thumbsup: I admit I miss the joke but I have laughed nevertheless:).
Thanks Les:thumbsup:. Who would have ever thought we could have such a comprehensive street directory.
15-12-2010, 09:13 AM
It would be good to see an overlay of voids on the various surveys (including the CMBR). I've seen snippets here and there, but no in depth analyses attempting to correlate the two.
The idea that matter condensed first in the cooler regions of the CMBR maps should turn up in the locations of the voids (on the large scale structure view).
15-12-2010, 09:31 AM
Yes indeed Craig.
I suppose what I was hinting at was although these regions perhaps present as uninteresting because of their lack of stuff it is that lack of stuff that is very interesting... why should we find it to be like this?
I asked a chap (scientist) and he dismissed it along the lines of "what we find appears consistent with the big bang" but clearly that was an off the cuff unconsidered view in my view and I think he missed the opportunity of gaining knowledge from thinking about nothing:rolleyes:
I wonder why there were some spots cooler than others? Easy to say well it was just that way but in the environment of the early big bang inconsistency seems to be out of place. I mean why did we not end up with just a thinner soup of stuff all over rather than the clumping observations show to us.
15-12-2010, 09:49 AM
Take a look at Bojan's new thread (http://www.iceinspace.com.au/forum/showthread.php?t=69438) (& my recent post there).
Looks like they are on the trail of what you suggest ! (Always beaten to the punch on new ideas, eh Alex ? :lol:;):) )
The splitting of the fundamental forces, early in the sequence, would seem to suggest these forces were a primary determining factor of what happened as things cooled down. The re-ionisation epoch would seem to hold the key to this one.
Interesting that scientists can't resist looking for patterns once they've generated a data set.
Penrose is looking for circles .. no doubt your associates, (where you live), look for patterns in tea-leaves ! I wonder what the difference is between the two approaches ?? … (just kidding .. don't take me seriously) …
15-12-2010, 10:32 AM
Before the NET one could believe original ideas were plentiful but it seems not so.
Funny one day I was thinking one could have a "solar" hot air balloon and of course when I looked just on utube there were so many it made me laugh.
I have mentioned before I invented the electric motor when I was 11 years old but ignorant that i was way behind the pack. OR my trumpet mirror ..mmm yes thats what they use in the xray scopes in Chile ...even the flying ring had been done before.
I dont feel upset by getting beaten but my faith in myself is uplifted by finding real evidence that what seemed like a crazy idea is a reality somewhere.
So many of the things I "saw" years ago are now common place.
The tea leaf set eh... you have no idea what its like listening to folk who believe in spirits, 2012, tarot cards etc and still hold oneself back from judgments.
My tarot card mate has just purchased one of those Tesla coil kits with little attachments for various health issues . Quiet a collectors item really however scary to look at it arc with a large spark from the glass attachment to his body.. he has no idea how it works but is convinced of its benefits..has a magnetic mattress as well...what can you say?
Still my view of their ignorance is probably similar to the ignorance some here would give to me when I dont readily accept big bang or dark matter as a given... So it is helpful for me to understand how others may regard my views.
I read Bojan's link earlier and found it very interesting and is probably what got me thinking about things today.
It would seem that such an experiment would be better set up in space well away from other "radio" sources ...but how clever of those guys doing so much with relatively cheap gear.
I like pattern approach. Playing guitar is about patterns (scale patterns) once you have the pentatonic scale pattern (any scale really) in one key you simply move it up or down the fret board and using the same pattern have the scale in another key. Learn one patten and you have arrived as a lead player so simple.
Human behavior often follows patterns and often repeating mistakes can be better understood when you see the pattern of behavior. I identified a pattern I had with chasing members of the opposite sex:eyepop: I changed my "pattern" and now am able to live happily and never again will get sucked in the way I once did:rolleyes:...
Anyways plan spending a bit of time on this today already got a list of links to look at... and how good is that..once one would have to go on a waiting list for a book to learn stuff but now you can learn off utube or check out the very university where particular research is being conducted... Its fantastic.
15-12-2010, 02:08 PM
15-12-2010, 03:09 PM
Thanks but now its complexity rules out it being funny:rolleyes:
It is the worlds within worlds or the proposition of multiple dimension thingy that seems apparent... the complexity humans can generate by the simple application of imagination is wonderful is it not.
Why when others play with their imagination they get a pat on the head but when I do it I am told I am subversive:shrug:...
I like to learn at least one new thing each day ..today I have learnt at least one thing more...so how good is that.
I am now going to the pub to try out some "e" jokes on the unsuspecting and confirm in their minds I am totally crazy.
Been here all day so far trying to understand why the prospect of a HB is less fanciful than the concept of an aether..they present a particle they cant find that gives mass I present just as illusive a particle to convey gravity and yet one is reasonable and the other, mine, beyond conception...what do I miss here? It is another joke right?
..man there are such wonderful clips on utube about HBs quarks dark matter dark energy black holes and all that stuff but so little on the fundamental importance of "e"....it is really just all too much for this ignorant hill billy in one day:P
But on a serious note is it not wonderful one can go to utube and attend lectures by Leonard Suskin, or hear Prof Higgs discuss his view or get a crash course in particle physics and look at visualizations about anything we can conceive, predict or speculate upon.
15-12-2010, 03:21 PM
I ran away in fright when you started talking about some guy using a Tesla coil on himself !!!
He must be an EU plasma guy, eh ? Better watch out for yourself out there !
Someday I'd like to understand the difference between a Higgs Field, and an Inflaton Field. I think the aether is merely out of fashion.
I agree with you about the web though. Totally terrific, if you ask me.
No more waiting forever to learn up on something. Instant information !
Fantastic stuff !
Merry Christmas to you. Have fun at the pub !
15-12-2010, 03:31 PM
No... he is a tarot card reader who believes in personality reincarnation and the danger of aura invasion from dead evil spirits but to his credit he sees the concept of an electric universe as simply too fanciful for his reality...nothing unusual there.
Just been checking out, on utube, a famous physicists playing the bongos and scatting at the same time... from that one could think he is strange but given his contributions to science I say he is OK...do you know to whom I refer?
AND a Merry Xmas to you and yours Craig...
15-12-2010, 03:34 PM
Hang on …
Who is it ??? Ya gotta tell us !!
I'll probably have to go and rip one of my books up !!
I'd prefer it to be Kaku … I think he's gone a bit awol lately !!
PS: (Just don't let it be Susskind) !
15-12-2010, 03:52 PM
Upon the aether ... I agree it is a fashion thing.
Clearly the MM experiment is regarded as the nail in the coffin for the aether and as far as the word itself is concerned I suspect it is dead.
After all how can something envisaged by those ignorant Greeks have any relevance in todays world. Those "Atomists" were on the money but clearly those who presented the aether were doomed to drift into rejection.
However we still have all these fields out there (and down here) that when described even in the most delicate and scientific fashion spell out a very similar concept. So I suggest we simply need a new word to describe "nothing" with more excitement than the concept of nothing projects.
I can not imagine a place where there is nothing and so I reach for the term aether. I do like "cosmic foam" or "quantum foam" but they were raised a long time ago now and has not really caught on ..and that is a pity because at least one very famous man liked the term enough to use it.
No doubt what we need is a new term that does not confront the findings of M and M ( so famous they named chocolates after them) but describes the reality we must deal with.
I do like the Higgs field... is it new as far as the populace is concerned and has enough cred as far as the scientific community is concerned to fit the bill... all I wonder is how everything can pass thru nothing and still remain unrecognized as perhaps a major player in the workings of the Universe.
Maybe someone at the Drake Pub can help me out on that one as it may be that knowledge can be gleaned from the analysis of the foam left in an empty beer glass such that it can rank with the wonderful art of tea leaf reading:D.
15-12-2010, 03:56 PM
Also been listening to your hero E W. He has a bit on utube. Is that not wonderful to hear a chap like that talk to mere mortals. Very nice. A master of understatement and reserve.
Love his measured chat style and in what I saw his ability to make so much manageable.
15-12-2010, 04:02 PM
Don't you dare tell me it was Ed playing the bongos, etc !!
I'd have to hide in shame !! .. A name change for me also !!
Nah .. Ed is way too refined for that .. go on .. who was it playing the Bongos??
15-12-2010, 04:47 PM
Richard Feynman plays the bongos (http://www.youtube.com/watch?v=HKTSaezB4p8).
15-12-2010, 09:04 PM
Starts with the letter "F"
A well respected member of the group.
15-12-2010, 09:05 PM
Yes it is the man.
We forget his input but he was one of the greats.
15-12-2010, 09:10 PM
Dam it lost the first round of pool. What was to be a $150 night turned out rather flat. I can not believe I lost I would not have played if I was to lose and wasted so much time there but I lost... still the guy who beat me is so very happy cause I never lose at pool...getting old etc.
I wonder how time would move inside one of these great voids, away from gravity.
If time does move faster would it distort the distances that are measured to objects whose light passes through it?
If we accept that that the universe is expanding at an accelerated rate how would time affect the expansion inside one of these voids?
Or is it doctrine that the universe is expanding uniformly at every point?
I need to get some sleep at night so any credible reply would help
17-12-2010, 07:06 PM
I would imagine space time would be as flat as you would find if there is no matter...although maybe they packed with dark matter.
Short answer is I cant offer a supportable view but I do think these are the sort of questions the voids must present to us.
18-12-2010, 08:04 AM
Time is relative. Thus, you'd need to rephrase your question from a non-moving observer and a moving traveller's perspective(s).
If I understand your starting assumptions correctly, then the answer would be 'no.'
As a matter of fact, if you're asking what would happen if we looked at a distant star through an 'intervening' void then, because there is no dense matter along the line of sight, the light from the star would take a clear, straight path directly through the void and we'd receive a perfectly undistorted image of it. The redshifted light, would be very representative of its distance and also take into account the expansion of the intervening space in the void. (This redshift is not what I'd call 'distortion' of the image).
Time would have no effect on the expansion. The cause of the expansion of space is not yet known. Dark Energy is theorised as its cause.
Beliefs are not mandatory. There is no 'doctrine'.
The currently supported mainstream Cosmological Model of the Universe includes the expansion of space. Redshifted light observations originally done, (at the largest scales), by Hubble show that the more distant the object, the faster the recession of it, and this applies from any observation point chosen. This leads to Hubble's Law. From this we can derive the age of the most distant visible objects, leading to the age of the observable universe.
All this is based on empirical observation based data. The concept of Redshift results in the expansion model.
Hope this helps.
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