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turbo May22-04 10:43 PM

virtual particles and cosmological expansion
 
I re-read parts of "Genius" by James Gleick earlier today after visiting a web-site that discussed steady-state cosmology. Apparently, Feinman felt that the creation and obliteration of virtual particles (diagramed by equivalent waves moving BOTH forward and backward in time) supported the idea of a steady-state universe, since the energy of both waves had to be exactly equal to make some serious problems in quantum mechanics go away.

However, if the universe is tending toward a homogeous state (entropy), it seems to me that the time-forward wave in each virtual-particle creation would not need to be "quite" as energetic as the time-reversed wave, which would be traveling to a more highly ordered previous state. The differential in energy between the two waves communicating the existence of any particular virtual particle would be miniscule, but if our universe is suffused with a dense sea of them, that difference in energy could have significant effects on our universe. Could the huge deficit of dark energy that cosmologists are looking for be accounted for by the entropy-gradient experienced by a sufficient number of virtual particles? If the energy deficit due to entropy is large enough and the particles are numerous enough, they could do the job without being observable. In addition, the entropy deficit "might" be sufficient to cover the observed Cosmic Background Radiation.

I apologize if these "inspirations" have been covered innumerable times in the past. I'm just an engineering-oriented amateur astronomer bumbling about in cosmology because I like the mental exercise.

Olias May23-04 12:09 AM

Quote:

Quote by turbo-1
I re-read parts of "Genius" by James Gleick earlier today after visiting a web-site that discussed steady-state cosmology. Apparently, Feinman felt that the creation and obliteration of virtual particles (diagramed by equivalent waves moving BOTH forward and backward in time) supported the idea of a steady-state universe, since the energy of both waves had to be exactly equal to make some serious problems in quantum mechanics go away.

However, if the universe is tending toward a homogeous state (entropy), it seems to me that the time-forward wave in each virtual-particle creation would not need to be "quite" as energetic as the time-reversed wave, which would be traveling to a more highly ordered previous state. The differential in energy between the two waves communicating the existence of any particular virtual particle would be miniscule, but if our universe is suffused with a dense sea of them, that difference in energy could have significant effects on our universe. Could the huge deficit of dark energy that cosmologists are looking for be accounted for by the entropy-gradient experienced by a sufficient number of virtual particles? If the energy deficit due to entropy is large enough and the particles are numerous enough, they could do the job without being observable. In addition, the entropy deficit "might" be sufficient to cover the observed Cosmic Background Radiation.

I apologize if these "inspirations" have been covered innumerable times in the past. I'm just an engineering-oriented amateur astronomer bumbling about in cosmology because I like the mental exercise.

The 'sea-of-Vacuum' particulates is where Feynman introduced the 'Single-Electron' statement, this is the crux of E-M field theory.

If one follows an Electron in Feynmans path integral systems, then where ever you trace the path, it will be revealed as everywhere the same instant, this means that Entropy Paths are always close to Equilibrium.

The fact of the matter is that Vacuum Lengths are certainly NOT the same size, because of dimensional constriants.

Let me handwave you if I may, a Backward wave would always be moving towards the big-bang, and therefore it has originated from a 'smaller' area/volume, it moves from a smaller environment (past-tense) to a larger enviroment (present-tense), the Arrow of Time(not to be confused with a Feynman Path History) pruduces two distinct lenths!

Think about it :rolleyes:

turbo May23-04 09:41 AM

Thanks for the explanation, and a follow-up, if you will...
 
I can see how the paths of the backward and forward waves can have different lengths, although I didn't realize that they must be different. What got me thinking, though, is that the virtual particle's Past emission/absorption node exists at a less entropic state than its Present emmission/absorption node. I sketched out a simple Feynman diagram with an arrow of time below it, and realized that in an expanding universe, the arrow of time also represented an entropy gradient. It seems to me that the entropic difference between the Past and Present nodes needs to be expressed somehow. After all, we expect to see some kind of emission whenever a particle drops to a less-energetic state. Why should we not expect something similar with respect to virtual particles when the nodes at which they create/annihilate are at different states?

Am I missing something really elementary?

Olias May23-04 04:16 PM

Quote:

Quote by turbo-1
I can see how the paths of the backward and forward waves can have different lengths, although I didn't realize that they must be different. What got me thinking, though, is that the virtual particle's Past emission/absorption node exists at a less entropic state than its Present emmission/absorption node. I sketched out a simple Feynman diagram with an arrow of time below it, and realized that in an expanding universe, the arrow of time also represented an entropy gradient. It seems to me that the entropic difference between the Past and Present nodes needs to be expressed somehow. After all, we expect to see some kind of emission whenever a particle drops to a less-energetic state. Why should we not expect something similar with respect to virtual particles when the nodes at which they create/annihilate are at different states?

Am I missing something really elementary?

Not really, its a common mistake:I can see how the paths of the backward and forward waves can have different lengths, although I didn't realize that they must be different. What got me thinking, though, is that the virtual particle's Past emission/absorption node exists at a less entropic state than its Present emmission/absorption node.

So common in fact it is taken as fundemental fact?..but let me enlighten you more, any wave which has a directional factor deemed to be from past, would have to be a Contracting wave (actually the technical wavefunction moves inversely, because it has a number of configurations, first it Expands close to source,Present-Time then it is observed as a static wave at a certain distance from source,Equilibruim of Present and Past-tense, then it has to become Virtual due to Universal expansion/contraction constraints, the Universe would have to become smaller, so the Wavefunction must contract in order to remain inside the ever decreasing Universe!) these quantities are defined as 'Transformations of Relative to Virtual'?..but I have the full working model, and have developed the correct paramiters for evolving 'Virtual' wavefunctions, if I drop out of University then I will post them here on the Web.

Out of curiosity in How many Dimensions did you calculate?

turbo May23-04 07:06 PM

Calculate?
 
:confused: Unfortunately, my curiousity and imagination routinely outstrip my math skills. I probably don't posses the skills to calculate the effects of expansion/entropy on a virtual particle pair in any dimensions. I'm just an amateur astronomer (chemist/papermaker/musician/fly fisherman :smile:) who is getting fascinated by cosmology rather late in life.

I love to read about astronomy and cosmology, and it seems to me that some problems that cosmologists are facing (missing mass, missing energy to drive the expansion) might be addressed by a better understanding of the virtual particles that populate the "empty spaces" that apparently comprise 99.9999999% ( I probably should have held the "9" key for at least another second) of our universe. These virtual particles are not a simple "thought experiment" - their existence is mandatory in quantum physics, and they have been proven experimentally by the Casimir Effect. Virtual particles not only cause measurable energy changes at the atomic level, they also exert measurable pressures on real-world objects.

Chronos May26-04 04:24 AM

interesting. i would argue the net energy state of the universe must be zero. if we agree the universe exists [hard to argue that point], and it only permits predictable states of existence, it must also, therefore, include a time dimension and 3 spatial dimensions to make it definable. we otherwise do not have the math to even make the attempt. current state: quantum physics insists the universe cannot stand still. GR insists it must either be expanding, contracting, or perfectly balanced [as einstein preferred]. friedmann's sum over history model seems to be a satisfactory explanation. the casmir effect, imo, affirms the space time continuum tends to expand.

turbo May26-04 06:56 PM

effects of the vacuum
 
It is easy for folks to "null" the vacuum as a mathematical convention when considering large-scale cosmological effects. After all, the sea of virtual particles are particle-antiparticle pairs, or perhaps other menageries, that annihilate each other so quickly (in accordance with the uncertaincy principle) that they can be conveniently ignored in lots of calculations, or so we think.

The Casmir effect, however proves that even on a macroscopic scale there is a difference between the pressures generated by the virtual particles arising in an unbounded vacuum as opposed to the pressures that can be generated by the smaller numbers of virtual particles that can be generated in an equivalent, but bounded, space. In our universe, empty space (vacuum) is not empty. Nor is it without measurable physical effects. Empty space forms the vast majority of the universe we live in (does anybody here have a quick measure of the ratio of space occupied by visible matter:vacuum?), and it seems that we must take into account the macro-world effects of the the quantum activities in the all-pervasive vacuum before we can hope to understand the universe, or even approximate its curvature.

Olias May26-04 11:29 PM

Quote:

Quote by Chronos
interesting. i would argue the net energy state of the universe must be zero. if we agree the universe exists [hard to argue that point], and it only permits predictable states of existence, it must also, therefore, include a time dimension and 3 spatial dimensions to make it definable. we otherwise do not have the math to even make the attempt. current state: quantum physics insists the universe cannot stand still. GR insists it must either be expanding, contracting, or perfectly balanced [as einstein preferred]. friedmann's sum over history model seems to be a satisfactory explanation. the casmir effect, imo, affirms the space time continuum tends to expand.

One can really make a good case of there being that all of Einsteins GR-SR and for that matter Friedman-Walker based sums-over-History, all relate to a single Galaxy. We can derive all of G-R and F-W equations backwards in time until our Galaxy dissapears, all Time paramiters can cease at this moment, we are no longer here, our Galaxy 'Time' dissapears and we are left with Einsteins Field Equations, the next 'nearest' Galaxy takes on the role of reference with Time Paramiters.

The Casimir effect is nothing more than a process of Phase Exchange(Fusion-Force) really? Let me give you an example where you can produce a similar force between SOLIDS and LIQUIDS.

1) Take any 2 old (compacted disks) C-D'S or CD-ROMS and as these are highly compacted their surface's are machined to a high polished finish, or simply very Smooth.

2)Now place a one on top of a table with the 'mirrored' surface facing upwards. Place the other C-D on top with mirrored surface facing the first C-D, now try and carefully lift the top C-D from the bottom C-D, it comes away as you would expect!

3)Now repeat (2) this time adding a little Liquid to the surface of C-D that is on the table, then press the second C-D home onto the first. Now try and lift away?..what happens is the two Solids (C-Ds) are Fused together, this Fusion is because of Vaccum caused along the Surface (phase) of C-Ds.

There has been an increase of Surface Tension by the introduction of Liquid, by pressing home the top C-D you create a 'false'
Vacuum along the Liquid Molocules, this creates a FUSION of the two Solids,(leaving aside technical details of molecular make-up).

Now lets look at the Macro comparable process, how Nature creates Stars? Yo are familiar with the energy process known as Fusion, it forms at the heart of Stars, but what and where do Stars come from?

Stars appear out of Vacuum in Space. When two Vacuum Flucuations, or Branes collide, they Collapse the Vacuum as they cross each other, out of this emerges Galaxies, in an instant the Casimir-Force welds matter through Fusion. Stars start to shine as the passing Branes move outwards, and Stars produce a Positive Pressure via thier PHOTON EMMISIONS, in this sense the Stars within a new Galaxy are Expanding the SPace around them, which reduces the Vacuum Density of the surrounding Space.

The experimental Casimir-Effect is a 'poor-mans' version of Macro Cosmic Creation, each Galaxy has its own Spacetime fused in and around the Galactic Volume, the beginning of our SPACETIME does not correspond to every other Galaxy in the Universe, it is a perceptional thing we look out from within a Galaxy and see expansion of other Galaxies away from us, these Galaxies have been born from the same process, colliding Brane, and as they appear to us at far away locations (except for Andromeda, which I speculate was born from the smae collision/collapse, the further the Branes move away the more Relaxation of Vacuum Density which produces 'Backdraft' motion towards each other).

This is highly Speculative of course, but the framework of Time is located in and around Galaxies, time cannot be Universal for every Galaxy would shine with the same luminosity, and every Galaxy would be identical in every facet of size for instance.

Space without matter cannot have the same paramiter for Time as The curvature produced in space with matter. Time only exists in area's where three-dimensional matter exists, as soon as you collapse a 3-D into a 2-D field then Time falls away into the Virtual Vacuum of Inter Galactic E-M Flat brane dimensions.

Olias May29-04 06:51 PM

Defining Boundery Conditions of Alpha and Omega is comparable to asking is there an Equality of Space in multiple dimensions?

Dynamic Boundary Conditions occur where expansion meets contraction.

Question..Do all Unique dimensions Expand or Contract similtaneously?


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