A thought about dark energy - Page 2

xelasnave · #21 21-12-2006, 08:38 AM

Thanks for that I was aware of the move to giving neutrinos mass. A happy day for me because of the problem my gravity rain idea ran into re mass and travelling at C... There seems some suggestion that at atomic levels and lower? mass can travell at C. I am on a mission to work out (for myself) how gravity works on a particle to particle basis.. as stated in many places I believe gravity works in a pushing fashion somehow but exactly how at an atomic level or particle level fasinates me... and You hit on something I guess we can never hope to see anything really at atomic levels. I dont understand string theory but dont know that it really offers much to answer anything like I have in mind.To me it seems to have evolved to solve a reconcilliation problem before anything else. Thanks again..I have yet to read the link you provided which I will do with glee.
alex

xelasnave · #22 21-12-2006, 08:54 AM

I wonder how long a neutrino can live? I have thought that where the Sun stops its influence and "outter" space takes over at the very edge of or solar system, that maybe something like or indeed the nuetrino continues on to contribute to the pressure of dark energy,gravity rain whatever... I recall them having a very limited age but that may have something to do with coming thru our atmosphere. Anyways that was a great link, I cant manage the math but the argument is one of logic finally.. and I have seen the mass finding reported someplace.. it certainly suits my ideas of things.
Thanks again
alex

xelasnave · #23 21-12-2006, 08:57 AM

Also Glen if you are there I am still reading links and follow up from your posting thanks again.
alex

xelasnave · #24 21-12-2006, 02:30 PM

re Casimir force I liked this..
"People are not even sure if the force is attractive or repulsive."
alex

dcnicholls · #25 21-12-2006, 07:58 PM

Re neutrinos, they live for at least 200,000 years because there was a burst of them detected from supernova 1987a. AFAIK they don't decay at all as they're elementary particles. So they don't decay like neutrons do, for example. But they do oscillate between the different types of neutrino.

DN

xelasnave · #26 22-12-2006, 06:59 AM

Thanks for that. I like them (or similar particles) I can see how one star could fill a fair bit of space with them ..space that may already be filled with others from everywhere else... the result a pressure system in effect currently refferred to as dark energy..this system does away with the need for dark matter as the gravity (as I see it) is in effect a pressure imbalance in the nuetrinos (and other particle yet to be considered losely thought of as agraviton maybe) coming and going. Imagine at any point in space maybe a little bit of everything meets as of course is the situation at any point in space.. if you think losely that what we see as visable light represents each place a nuetrino or similar particle comes from and then think where in space you could stand and not be bathed in particles from everywhere even without sums I expect that there must be a considerable resultant pressure in effect my way of explaning how I recon it may work... Needless to say I enjoy speculating with the little bits of understanding that reaches me. Thanks again for that.
alex

xelasnave · #27 22-12-2006, 07:06 AM

mmm got me thinking about "nothing" again... what are elementary particles "suspended" in.... er nothing.. space.. an absence of everything but time I guess.
alex

glenc (Glen) · #28 25-12-2006, 08:58 AM

Explanation: Eight years ago results were first presented indicating that most of the energy in our universe is not in stars or galaxies but is tied to space itself. In the language of cosmologists, a large cosmological constant is directly implied by new distant supernovae observations. Suggestions of a cosmological constant (lambda) are not new -- they have existed since the advent of modern relativistic cosmology. Such claims were not usually popular with astronomers, though, because lambda is so unlike known universe components, because lambda's value appeared limited by other observations, and because less-strange cosmologies without lambda had previously done well in explaining the data. What is noteworthy here is the seemingly direct and reliable method of the observations and the good reputations of the scientists conducting the investigations. Over the past eight years, independent teams of astronomers have continued to accumulate data that appears to confirm the unsettling result. The above picture of a supernova that occurred in 1994 on the outskirts of a spiral galaxy was taken by one of these collaborations.

xelasnave · #29 26-12-2006, 03:33 PM

Thanks Glen ..there is some reading there.. I liked this little bit at the end of the Cosmological Constant notes..
quote..
So the cosmological constant behaves gravitationally like matter and energy except that it has negative pressure. The net effect of a positive cosmological constant is then to create a repulsive gravitational force. This repulsion acts to expand the universe.

The vacuum energy density behaves differently from matter and energy density in another regard. As the universe expands, matter and energy are spread out over more physical space and thus their gravitational attraction is diminished. For the vacuum energy, however, the PdV work done by the vacuum during adiabatic expansion provides exactly the amount of energy to fill the new volume to the same density. Therefore the cosmological constant remains truly constant, and its gravitational repulsion (or attraction) never changes during the universe's evolution".
Gives at least a 50/50 on the gravity push thing

alex

xelasnave · #30 26-12-2006, 04:05 PM

Whilst reading found this....
quote"
When Einstein introduced the cosmological constant in his theory of general relativity he did so because he was guided by the paradigm of the day that the universe was static (i.e. neither contracting nor expanding.) The cosmological constant provided a way of balancing the gravitational contraction caused by matter. It was latter discovered by Edwin Hubble that other galaxies appear to be receding away from us, that the universe was actually expanding. When Einstein heard and fully appreciated these observations, he declared that the inclusion of the cosmological constant was his "biggest blunder."

Einstein's mistake was not a mathematical one but rather a philosophical one made many times over the history of thought. Einstein held too strongly to the belief that the universe was static and thus was unable to appreciate the power of his theory's predictions of a dynamic universe. His error serves as an lesson to all thinkers, that we should never close our minds to new possibilities, even if the thought of the day is that they are impossible. Imagine how history would have been changed had Copernicus refused to accept his belief that the sun was actually the center of the solar system, or had Columbus thought he would have fallen off the edge of the Earth. It is hard to know where the next paradigm shift will come from, but we should always be waiting for it.
end quotes
I recon the next paradigm shift is to see dark energy as the pushing force responsible for gravity

... and I wouuld like to think the concept will apply whether or not a "start" is needed for the Universe

..
There is no hope for me but heck I am learning heaps on the way to realising that

.
alex

avandonk · #31 27-12-2006, 12:58 AM

I still think the answer lies in an holistic view of all we can perceive. Quantum entanglement gives us a glimpse of the interconnectedness of everything. Was not all space and time at one place at a time when time had not begun?
The 'virtual' particles that appear and disappear are also another clue. String theory may only give us a more complete but more baffling interpretation.
Multi dimensions and multi universes are even more disturbing than the problem of dark matter and energy. Are they manefestations of 'leaking' between universes or between times via some form of quantum entanglement.

We can barely work out some let alone all the connections of the web of life that sustain us all on one planet. Otherwise we (all of us) would not be disturbing them irreparably.

I have not proposed any answers merely a possible mechanism.
We live in interesting times.

Bert

xelasnave · #32 29-12-2006, 07:16 PM

Bert thank you for your insight.
Indeed when speculating on these matters many can think they have the answers when in fact if you had all the answers there would be no hard drive large enough to hold those answers..or on the other hand does it all come down to one simple sum..mmm I doubt that but on the bright side they only need zero and one as we conceive them to work on the sums...
I still think the implications of dark energy as a pushing force is underestimated more than not understood, as to have such a force becoming null and void somewhere above us to let attraction take over defies the logic I can muster..but then again I know very little of what there is to know..but thats my idea to date.
I know there is speculation of multi universe or parrallel Universes which are interesting ideas, frankly I dont accept those possibilities but again that could be a reflection of my ignorance of the possibilies and why they present to someone who has studied more than me.. and there would be a few.
There is so much to learn about and I find it so interesting but also frustrating being uneducated in the areas of interest to me.
Thanks again for your input
alex

glenc (Glen) · #33 08-01-2007, 06:33 AM

Astronomers have mapped the cosmic "scaffold" of dark matter upon which stars and galaxies are assembled. Dark matter does not reflect or emit detectable light, yet it accounts for most of the mass in the Universe.
The study, published in Nature journal, provides the best evidence yet that the distribution of galaxies follows the distribution of dark matter.
This is because dark matter attracts "ordinary" matter through its gravitational pull.
Scientists presented details of their research during a news conference here at the 209th meeting of the American Astronomical Society (AAS) in Seattle, Washington.
It involved nearly 1,000 hours of observations with the Hubble Space Telescope. ...............

http://news.bbc.co.uk/2/hi/science/nature/6235751.stm

xelasnave · #34 08-01-2007, 08:20 AM

Thanks Glen.
Needless to say from my point of view whilst they seek to use attraction to work it out the problem will confuse them. I was reading a astronomy mag from 1991 yesterday (and unfortunately left it in Sydney) but back then Vera Rubin was displaying photographic plates "showing" dark energy.
Your post is indeed timely for my project over the coming days (months) was to surf the net until I found some photos of this dark matter (those presented by Vera Rubin all those years ago or anything more current).. as I still say one can not photograph something that is not there. Still in fairness and to get a better understanding of the confusion, mine or theirs, I suppose I should look at everything I can find. So I am going thru NED and MAST again and whatever other data bases I can find to get leads on them all. I know its one nutter (me) against the worlds best scientists but I have won more difficult battles and am totally confident of the validity of my contention that dark energy derives from all bodies in the Universe creating a universal pressure (pushing force) which if one labours under the impression gravity attracts will have one seeking matter as a source of the attraction..and therefor seeking a non exsistent "dark matter"
Surprisingly I am not ignorant of the current thinking that galaxies need a clump of dark matter in which to form and think I have a fair overview of the current thinking on it..I see flaws in the approach taken simply because humans seek to include the force of attraction.. a force I deny exsists as an interaction between mass... but time will tell.
But I have placed my bets but am more confident with them than say a 50 to one long shot at the track.
Thanks again.. dont let your head fall off from shaking in disbelief of my stand against the apparent evidence.. and please keep the case against my ideas coming so I can dispatch them or get with the popular thought on these issues.
best wishes
alex