Where does new space come from as the universe gets bigger?

In summary: Scientists are describing space as space. It's a mathematical concept with certain well-defined properties. It's not a "thing" any more than distance is.In summary, space is something that is created by mass and gravity. It is not something that can be warped or distorted. Space is constantly referred to as a fabric.
  • #141
Mordred said:
ah but that results in quantum vacuum zero-point energy which is the lowest possible energy state, there is still a higher than the minimal state due to the uncertainty principle. As a consequence at absolute zero, that volume of space would have a lowest energy potential of

[tex]\frac{1}{2}hv[/tex]

which by the way is one point I mentioned during this thread is that there is always some energy-density, occupying space. You will always have either a positive or negative vacuum energy potential.

If I recall though this led to the biggest blunder, this process was once considered as a possible cause of the cosmological constant, however it was 120 orders of magnitude too large.

edit: this is in reply to Timmdeeg's post
I am not sure, aren't you confusing the quantum mechanical zero point energy and the zero-energy universe hypothesis (s. Wikipedia)? That's something else.
 
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  • #142
not really the zero-energy universe ( universe from nothing model is a zero-energy universe at the beginning and uses the zero-energy universe as a premise) uses quantum mechanics and the Heisenburg Uncertainty principle, to form the initial virtual particle production. The two are related.

Not to say that is the only treatment that uses the zero-energy universe. Allen Guth's original false vacuum also used the zero-energy universe.

http://arxiv.org/pdf/gr-qc/0605063.pdf

edit: forgot to mention a perfect zero-energy universe would be flat and static. Which would be unstable, I'm sure from that statement you can see the connection between the cosmological constant and the quantum zero point energy
 
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  • #143
Mordred said:
forgot to mention a perfect zero-energy universe would be flat and static.
Ah, that seems to be the misunderstanding. The negative gravitational energy
does not contribute to the stress energy tensor.

http://en.wikipedia.org/wiki/Zero-energy_universe
 
  • #144
you might be interested in this historical development of zero point energy.

"Preludes to dark energy:Zero-point energy and vacuum speculations." http://arxiv.org/ftp/arxiv/papers/1111/1111.4623.pdf. covers a lot of the historical aspects. Just figured you would find it interesting
 
  • #145
Thanks, interesting article.

However this statement
Mordred said:
forgot to mention a perfect zero-energy universe would be flat and static.
isn't clear to me. Are you saying that the zero-energy universe hypothesis (matter energy canceled by gravitational potential energy) implies necessarily that the RW-universe is flat and static? If yes, how would you explain that? And saying flat you mean spatially flat (not flat space-time), right?
 
  • #146
timmdeeg said:
... whereby the positive energy of matter/radiation is canceled by its negative gravitational potential energy according to the zero-energy universe hypothesis.

step back and think about this statement. Let's use GPE for total gravitational potential, let's use VPE for negative gravitational potential, (Vacuum gravitational potential)

if GPE+VPE=0 this equals a perfectly flat universe. One whose total energy densities is equal to the critical density.

Now we already know from the Einstein field equations that a static universe is unstable. The EFE predicts either a contracting or expanding universe.

1) So how is a zero-energy universe defined in a universe with curvature?
2) How does a zero-energy universe evolve or contract?

The solutions to question 1 is rather tricky, the paper I posted shows the use of pseudo tensors and states that you cannot use polar coordinates, or spherical coordinates. You must use Cartesian coordinates.
http://en.wikipedia.org/wiki/Pseudotensor
this tensor is also used
http://en.wikipedia.org/wiki/Stress–energy–momentum_pseudotensor

the answer to number 2 is also tricky, remember according to the zero energy universe, the only two parameters you need to describe the dynamics of the universe is GPE and VPE.

so in order to expand it follows that globally VPE>GPE, to contract GPE>VPE. The paper slices the global into local with pseudo tensors and cartesian coordinates,
http://en.wikipedia.org/wiki/Cartesian_coordinate_system

needless to say the model gets complex, compared to LCDM. You can see this from the above, and I haven't even included quantum effects such as particle pair creation and quantum tunneling. Inflation (False vacuum) like I said makes use of the zero energy universe, then adds those quantum effects. Which creates an imbalance between GPE and VPE. When inflation stops GPE=VPE once again.

There is numerous controversies on this model, and I haven't studied it in a while. However that's my understanding of it. The use of pseudo tensors itself is one source of controversy
 
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  • #147
Universe bigger?

The universe is only stretching, everything in it is co-moving with space. No new space is generated. Our visible universe is only a part of a much bigger universe, laid there by inflation. So the question is: do we see new structures while stretching? A couple of decennia ago that was possible when the horizon moving with the speed of light could catch a light ray from a galaxy behind the horizon who was decelerating with the universe. Than it was possible to see new structures.
But since the discovery of an accelerating universe we never again will see new structures.
 
  • #148
Discman said:
The universe is only stretching, everything in it is co-moving with space. No new space is generated. Our visible universe is only a part of a much bigger universe, laid there by inflation. So the question is: do we see new structures while stretching? A couple of decennia ago that was possible when the horizon moving with the speed of light could catch a light ray from a galaxy behind the horizon who was decelerating with the universe. Than it was possible to see new structures.
But since the discovery of an accelerating universe we never again will see new structures.

Welcome to the forum, However please read the entire thread before posting in that thread. In particular what we have repeatably said about the terminology stretching and how incorrect that term is. Also read the Redshift and expansion article posted earlier in the thread concerning how light can reach us in regards to expansion, and the Hubble sphere.
 
  • #149
He's talking about inflation, in which case objects beyond the event horizon are indeed never to be seen again...
 
  • #150
event horizon

According to me is inflation a temporary event, it halted, so here is in principle not an event horizon. The accelerated universe will go on forever. The Hubble radius will be at one time forever lagging behind and there is the event horizon.

But I am quite new here so I will at the moment not interfere to much. I will accommodate at first. The aim of my first answer was to get on the main road again from the original question after being lost in all the side ways of the threads.
 
  • #151
You need observational evidence to support any model, Discman. That is the problem I see with your model.
 
  • #152
Mordred said:
Quote by timmdeeg
... whereby the positive energy of matter/radiation is canceled by its negative gravitational potential energy according to the zero-energy universe hypothesis.
step back and think about this statement. Let's use GPE for total gravitational potential, let's use VPE for negative gravitational potential, (Vacuum gravitational potential)

if GPE+VPE=0 this equals a perfectly flat universe. One whose total energy densities is equal to the critical density.
There is still a misunderstanding. I have mentioned the article http://en.wikipedia.org/wiki/Zero-energy_universe in post # 143.
The zero-energy universe hypothesis states that the total amount of energy in the universe is exactly zero: its amount of positive energy in the form of matter is exactly canceled out by its negative energy in the form of gravity.
It originated in 1973, when Edward Tryon proposed in the Nature journal that the Universe may have emerged from a large-scale quantum fluctuation of vacuum energy, resulting in its positive mass-energy being exactly balanced by its negative gravitational potential energy
The spatial curvature depends on the comparison of observed and critical density according to
[tex]\Omega \equiv \frac{\rho}{\rho_c} = \frac{8 \pi G\rho}{3 H^2}[/tex]
The density ρ is well defined and there is no contribution of any negative gravitational potential energy. In case you disagree kindly show relevant literature. Therefore I don't see that the "The zero-energy universe hypothesis" determines the spatial curvature of the universe. In other words this hypothesis is not restricted to a certain case. It applies to a RW-universe containing matter/energy but is not a physical theory witch predicts certain observations.

Mea culpa, this is a side discussion, perhaps we should come to an end.
 
  • #153
The spatial curvature depends on the comparison of observed and critical density according to
[tex]\Omega \equiv \frac{\rho}{\rho_c} = \frac{8 \pi G\rho}{3 H^2}[/tex]

Yes this is correct, I merely showed the difficulty the model has when describing a universe whose observed density does not equal the critical density.(like our own universe, our universe is close to flat) A critically dense universe is flat and static, which is inherently unstable.

Your right though, we should keep the thread back on topic

edit:ps I don't see a disagreement with your last statement
 
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  • #154
Mordred said:
A critically dense universe is flat and static, which is inherently unstable.
Why do you say static? Flat FRW is not static.
 
  • #155
Hows is new space created

CosmicVoyager said:
Greetings,

How is new space created?

There was no space before the big bang, correct? And the universe is still getting bigger? So the amount of space is increasing.

Where did and does it come from? Space is something not nothing correct? It can be stretched, compressed, and curved.

Is something being converted into space? I heard mention somewhere that gravity was being converted into space.

Thanks

I don't think anyone knows the answers to these questions. We don't know if there was no space before the BB because there is no information from before the BB.
 
  • #156
bapowell said:
Why do you say static? Flat FRW is not static.

yeah I keep getting that mixed up with a static universe, which is flat.
 
  • #157
More space?

By definition the universe comprises everything that is, that was in the past en that will come in the future. So space is always included in the universe independent if it grows or shrinks. Are we not busy with a contradictio in terminis?
 
  • #158
One way to look for a vacuum energy density is to study the orbits of particles moving in the gravitational field of known masses. Since we are looking for a constant density, its effect will be greater in a large volume system. The Solar System is the largest system where we really know what the masses are, and we can check for the presence of a vacuum energy density by a careful test of Kepler's Third Law: that the period squared is proportional to the distance from the Sun cubed. The centripetal acceleration of a particle moving around a circle of radius R with period P is
a = R*(2*pi/P)2
which has to be equal to the gravitational acceleration worked out above:
a = R*(2*pi/P)2 = g = GM(Sun)/R2 - (8*pi/3)*G*rho(vacuum))*R
If rho(vacuum) = 0 then we get
(4*pi2/GM)*R3 = P2
which is Kepler's Third Law. But if the vacuum density is not zero, then one gets a fractional change in period of
dP/P = (4*pi/3)*R3*rho(vacuum)/M(sun) = rho(vacuum)/rho(bar)
where the average density inside radius R is rho(bar) = M/((4*pi/3)*R3). This can only be checked for planets where we have an independent measurement of the distance from the Sun. The Voyager spacecraft allowed very precise distances to Uranus and Neptune to be determined, and Anderson et al. (1995, ApJ, 448, 885) found that dP/P = (1+/-1) parts per million at Neptune's distance from the Sun. This gives us a Solar System limit of
rho(vacuum) = (5+/-5)*10-18 < 2*10-17 gm/cc
The cosmological constant will also cause a precession of the perihelion of a planet. Cardona and Tejeiro (1998, ApJ, 493, 52) claimed that this effect could set limits on the vacuum density only ten or so times higher than the critical density, but their calculation appears to be off by a factor of 3 trillion. The correct advance of the perihelion is 3*rho(vacuum)/rho(bar) cycles per orbit. Because the ranging data to the Viking landers on Mars is so precise, a very good limit on the vacuum density is obtained:
rho(vacuum) < 2*10-19 gm/cc
Milky Way Galaxy
In larger systems we cannot make part per million verifications of the standard model. In the case of the Sun's orbit around the Milky Way, we only say that the vacuum energy density is less than half of the average matter density in a sphere centered at the Galactic Center that extends out to the Sun's distance from the center. If the vacuum energy density were more than this, there would be no centripetal acceleration of the Sun toward the Galactic Center. But we compute the average matter density assuming that the vacuum energy density is zero, so to be conservative I will drop the "half" and just say
rho(vacuum) < (3/(4*pi*G))(v/R)2 = 3*10-24 gm/cc
for a circular velocity v = 220 km/sec and a distance R = 8.5 kpc.
Large Scale Geometry of the Universe
The best limit on the vacuum energy density comes from the largest possible system: the Universe as a whole. The vacuum energy density leads to an accelerating expansion of the Universe. If the vacuum energy density is greater than the critical density, then the Universe will not have gone through a very hot dense phase when the scale factor was zero (the Big Bang). We know the Universe went through a hot dense phase because of the light element abundances and the properties of the cosmic microwave background. These require that the Universe was at least a billion times smaller in the past than it is now, and this limits the vacuum energy density to
rho(vacuum) < rho(critical) = 8*10-30 gm/cc
The recent supernova results suggest that the vacuum energy density is close to this limit: rho(vacuum) = 0.75*rho(critical) = 6*10-30 gm/cc. The ratio of rho(vacuum) to rho(critical) is called ΩΛ. This expresses the vacuum energy density on the same scale used by the density parameter Ω. Thus the supernova data suggest that ΩΛ = 0.75. If we use ΩM to denote the ratio of ordinary matter density to critical density, then the Universe is open if ΩM + ΩΛ is less than one, closed if it is greater than one, and flat if it is exactly one. If ΩΛ is greater than zero, then the Universe will expand forever unless the matter density ΩM is much larger than current observations suggest. For ΩΛ greater than zero, even a closed Universe can expand forever.
 
  • #159
Addenda:
In the past, we have had only upper limits on the vacuum density and philosophical arguments based on the Hansen-Dicke coincidence problem and Bayesian statistics that suggested that the most likely value of the vacuum density was zero. Now we have the supernova data that suggests that the vacuum energy density is greater than zero. This result is very important if true. We need to confirm it using other techniques, such as the WMAP satellite which has observed the anisotropy of the cosmic microwave background with angular resolution and sensitivity that are sufficient to measure the vacuum energy density. CMB data combined with the measured Hubble constant do confirm the supernova data: there is a positive but small vacuum energy density.
Our new 'toys', when used in conjunction with the Jodrell Bank radio telescope, allows us to 'see' again the Cygnus X-1 system in greater detail. We are calculating my previous numbers.
Look at Casimir(ZPE): en.wikipedia.org/wiki/Casimir_effect.
In short, and my take on it:
The force between any two macroscopic conducting surfaces, in a volume which only contains an electromagnetic field.
The zero-point energy of the electromagnetic field depends on the mode frequency of the field which in turn depends on the boundary conditions on the field, thus changing the positions of the surfaces, changes the mode frequencies and zero-point energy of the field. This energy change can be expressed as a potential energy unit area of the plates; as a function of the distance from the plates; which leads to a force between the plates. Both the sign and magnitude of the Casimer effect depends critically on the geometry of the surface of the plates.
Zero-point energy.
The energy remaining in a substance at the absolute zero of temperature.
This is in accordance with quantum theory in which a particle oscillating with simple harmonic motion does not have a stationary state of kinetic energy. Moreover, the Uncertainty principle does not allow such a particle to be at rest at exactly the centre point of its oscillation; ΔxΔp ≥ h/2π. Heisenberg’s Uncertainty principle dictates that the lighter a particle is, the less well defined is its position. Vacuum virtual particles are completely democratic and they will be created into any particle one knows of. The vacuum is a seething mass of energy, with particles flashing in and out of existence about their ‘zero-point’ baselines. Tests indicated that even in the depths of a vacuum chilled to absolute zero (-273.150c) the energy will not go away with millions, and perhaps billions, of fluctuations occurring in any given second producing a constant and churning foam of energy. If two aluminium plates were placed very close together, so close that their separation was less than the wavelength of the fleeting (tp) virtual particles in the quantum ‘effervescence’ it follows that there would be nothing between the plates. Everything outside the cavity made by the plates would still be seething with ZPE fluctuations, the external force pushing in on the plates ought to be enough to close them together, thereby proving the existence of the ZPE field. To exclude the wavelengths of the fluctuating particles the Casimer plates have to be exactly parallel and separated by less than a micron (μm = 10-6m). Created every second are billions of virtual particles, EMR and particulate, in every conceivable frequency and in every possible direction, there is (isotropically) theoretically speaking, no limit to the amount of energy resulting from the quantum foam of virtual fluctuations.
The upper limit of frequency is defined by the Hansen constant: sqrt[c^5/(h-bar)G]
The so-called singularity, which 'caused'(as causality) our universe, appears in string theory to have been a Planck-like quantum object of Lp diameter and of Mp mass vibrating at 10^43 hz.
As h-bar v =E =mc^2, it can be seen that the Planck quantum object, at the above frequency, existed between all quantum states, specifically mass and energy.
For each Planck-second the combinations and permutation of 'real' constants were 'tried' until,and at some point, a stable state was reached and the Planck-object expanded.
I cannot wait for your discussions!
 
  • #160
I know there is a simpler explanation of the so called Casimir Effect. The "pressure" supposedly caused by fluctuations is just as well explained by the interaction between the atoms of the two plates. The literature is out there. I can't claim any personal competence in this area, but it seems to me that the Casimir effect is an elegant explanation but doesn't satisfy Occam's Razor (ie Parsimony).
Oh, btw: could you point me to that region of our Universe "which only contains an electromagnetic field." Last I heard, there is no such never-never-land.
 
  • #161
that's not really what he's describing. perhaps this article will help which if I read his post correctly is referring to.

"Preludes to dark energy:Zero-point energy and vacuum speculations." http://arxiv.org/ftp/arxiv/papers/1111/1111.4623.pdf

its a historical coverage of vacuum energy research and how it was later applied to cosmology in the zero-energy universe. However it was later found to be 120 orders of magnitude too large. So either its not a mechanism to explain the cosmological constant, or there is some dampening mechanism in play we haven't determined yet. However there have been numerous experiments other than the casimiir experiment that show virtual particle production in a vacuum.
 
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  • #162
Frank Weil said:
To exclude the wavelengths of the fluctuating particles the Casimer plates have to be exactly parallel and separated by less than a micron (μm = 10-6m). Created every second are billions of virtual particles, EMR and particulate, in every conceivable frequency and in every possible direction, there is (isotropically) theoretically speaking, no limit to the amount of energy resulting from the quantum foam of virtual fluctuations.
Interestingly, according to R.L.Jaffe the Casimir force can be understood as a van der Waals force, without taking reference to the vacuum. He concludes: "Still, no known phenomenon, including the Casimir effect, demonstrates that zero point energies are "real"."

http://arxiv.org/PS_cache/hep-th/pdf/0503/0503158v1.pdf
 
  • #163
timmdeeg said:
Interestingly, according to R.L.Jaffe the Casimir force can be understood as a van der Waals force, without taking reference to the vacuum. He concludes: "Still, no known phenomenon, including the Casimir effect, demonstrates that zero point energies are "real"."

http://arxiv.org/PS_cache/hep-th/pdf/0503/0503158v1.pdf

This question posits that vacuum/zero point energy concerning Heisenberg’s virtual particle jitter around the zero point cannot/doesn't exist?
One aspect of this is the quantum vacuum and the quantum foam, of say virtual electrons popping into existence and then vanishing again. This is no mere theory. It actually has observable consequences.
The rolling sea, or more precisely, the foaming bulk of the quantum vacuum buffets the outer (valence) electrons in atoms very slightly, and changing the energy of the light they give out. (hv) The effect is called the Lamb Shift.
This virtual particle interaction with mass(ive) (real) particles along with the ubiquitous background microwave radiation is the reason, why it will be impossible to [reach] zero Kelvin, because the Heisenberg Uncertainty Principle produces a residual jitter even at absolute zero.Simply a space-time volume is a null-Planck object. It is a pixel which is part of the quantum foam where virtual particles have their genesis. They have an intrinsic transitory structure where the three dimensions of space and the dimensions of time are in constant flux and chaotic disorder.
Each space-time pixel is a fundamental entity woven into the fabric of the cosmos.
Imagine that space-time was a gossamer sheet of the finest silk fabric. Under magnification each area bounded by the cross-hatching of the weave is to be seen as a ‘silk-time’ pixel (!). No matter how you may want to distort the fabric, each pixel will stay in order and in its place.
The translucence of the fabric is analogous to the individual dimensional flux of each pixel. To try to give space-time a volume (mathematically) is like trying to herd cats!
Entropy/thermodynamics is distorted and becomes meaningless... it’s like trying to fit a slightly too large carpet into a room. You get two corners fixed but no matter what you do or how you manipulate the carpet, it always leaves large bumps across it.
Ad hoc solutions by ’cutting’ corners is not physics!
At this point in scientific research, the Holographic Principle (from string theory, Susskind. et al), is taken to be, in some sense, analogous to the hologram, where a 3-dimensional image is perceived when a (basically) 2-dimensional surface is viewed. The most familiar form of this ‘holographic principle’ stemmed from work of Juan Maldacena and is sometimes referred to as the Maldacena conjecture.
My advice is to conjoin the other answers that have been supplied by the mathematicians,physicists,astrophysicists and cosmologists (students or academics) and for you to arrive at your own conclusion(s).
Casimir update:
A sheet of graphene is one atom thick which makes it the first two-dimensional object humans have ever created, seen and manipulated. The uses for such a material are still being investigated. Ultra-high frequency/ switching, transistors/diodes are one application.
The more exiting application is in zero-point energy research which we were working on in Wisconsin, (Quantum fields). Basically, the Casimir Effect is the negative pressure/ energy upon two metal plate separated by a very small distance. Placing and keeping these plates at such a small distance is very difficult due to alignment problems of the gold plates. This is where graphene is useful.
Using four grapheme packing shims on each corner of one of the plates and then bringing the two gold plates together; not only would/is the separation of the plates be precise and stable, but the distance between the plates would/is be only one atomic diameter. Fabrication of a complete monolithic ‘carbon chip’ with billions of these will follow. The chip will ‘sum’ the energy collected by the number of zero-point elements fabricated on the chip and would not require an external power supply.
It would be using energy extracted directly from the zero-point Heisenberg field.
Regards to everyone. and for your riveting (and) modern outlook/views and directions.
Thank-you.
 
  • #164
abitslow said:
I know there is a simpler explanation of the so called Casimir Effect. The "pressure" supposedly caused by fluctuations is just as well explained by the interaction between the atoms of the two plates. The literature is out there. I can't claim any personal competence in this area, but it seems to me that the Casimir effect is an elegant explanation but doesn't satisfy Occam's Razor (ie Parsimony)..

Thank you Abitslow,
'lex parsimoniae' does not ,and was never intended, to include Gödel's incompleteness theorem or/and the 'hidden variable'.

Wiki: Gödel's incompleteness theorem.
'The theorem that in any sufficiently powerful, logically consistent formulation of logic or mathematics there must be true formulas which are neither provable nor disprovable. The theorem entails the corollary that the consistency of a logical system cannot be proved within that system.' Un-Wiki(!)

Wiki: Hidden variables.
'Historically, in physics, hidden variable theories were espoused by some physicists who argued that the state of a physical system, as formulated by quantum mechanics, does not give a complete description for the system; i.e., that quantum mechanics is ultimately incomplete, and that a complete theory would provide descriptive categories to account for all observable behaviour and thus avoid any indeterminism. The existence of indeterminacy for some measurements is a characteristic of prevalent interpretations of quantum mechanics; moreover, bounds for indeterminacy can be expressed in a quantitative form by the Heisenberg uncertainty principle'. (un-Wiki.
 
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  • #165
abitslow said:
Oh, btw: could you point me to that region of our Universe "which only contains an electromagnetic field." Last I heard, there is no such never-never-land.

Sciama's equation:

T = h (c^3)/16(∏^2)GMK

This is your never-never-land.
It's a black-hole's temperature!
I think that you would agree that there are many regions of our universe which are enclosed by event horizon's AND have electromagnetic fields.
We can characterise uniquely these objects by three properties:
It’s mass, angular momentum and electric charge. Mathematical expressions have been derived for describing black holes. These are the SCHWARZSCHILD SOLUTION for uncharged non-rotating black holes. The REISSNER-NORDSTROM SOLUTION for charged non-rotating holes. The KERR SOLUTION for uncharged rotating holes, and the KERR-NEWMAN SOLUTION for charged rotating holes.
 
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  • #166
Frank Weil said:
This question posits that vacuum/zero point energy concerning Heisenberg’s virtual particle jitter around the zero point cannot/doesn't exist?
It is still possible to derive the Casimir effect based on the concept of zero point fluctuations, but as Jaffe showed, this is not a necessity. Therefore one can no more argue that this effect proofs the "reality of zero point energies" experimentally. It is worth to read at least "Conclusion".
 
  • #167
I've also never seen anyone demonstrate that Heisenberg's principle suggests in any rigorous way that virtual particles fluctuate out of the vacuum. I mean, I'm well aware that this idea pervades popularizations of QFT and is standard lore in professional physics...but my question is: does the HUP imply the existence of virtual particles outside of perturbative treatments of QFT?
 
  • #168
I cannot, and will not, take up any more space on this forum, as there are a lot of people itching to give you guys there definitions/answers etc.
I think that it can be seen/demonstrated that I have given enough of MY views...can we read/see/listen to other peoples points of view?
It just feels like that I would end up writing a dissertation on Casimir theory!...much to the displeasure of eager members of this forum.
I am fully aware of Andrew's (Jaffe) Chair and work in cosmology. He is well know and respected in astro/cosmo/math/physics.
However, he has the luxury of laying out his theories etc. by the page-load. We have only a couple of paragraphs in which to produce answers in,mostly, simplistic and analogous forms.
Not only is it an encumbrance, in as much that it may not exactly fulfil the answer to a more expert understanding , but it is done this way so that the people on the forum, who do not yet have all the mathematical and physics tools, can follow the line(s) of reasoning and concepts.
Thanks for listening!
 
  • #170
nice article, I'm also saving a link to the site its on. Could come in handy for research papers
 
  • #171
here is an interesting paper, discussing vacuum energy, please keep in mind I'm not trying to form anyone's opinions. Merely pointing out that the research is continually ongoing in understanding and utilizing quantum vacuum, as well as a possible explanation of dark energy

"A probable solution of the cosmological constant problem was recently found. We propose that dark energy of the Universe is vacuum energy. Our Universe during its expansion is spending its vacuum energy for creation of new microstates, but in the quantum regime phase transitions were more effective in reducing the vacuum energy than creation of new microstates. Here we show how the 123 crisis orders of the vacuum energy are reduced by
conventional physical processes in both the quantum and classical regimes of the Universe evolution. Numeral estimates of dark energy evolution are also presented. "

http://arxiv.org/ftp/arxiv/papers/1401/1401.4686.pdf

here is an article that discusses some of the test methods to extract power from vacuum energy.
http://www.calphysics.org/articles/Davis_STAIF06.pdf " Review of Experimental Concepts for Studying the Quantum Vacuum Field"

Assessment of proposed electromagnetic quantum vacuum energy extraction methods
http://arxiv.org/ftp/arxiv/papers/0910/0910.5893.pdf

Test of Zero-point Energy Emission from Gases Flowing Through Casimir Cavities
http://www.sciencedirect.com/science/article/pii/S1875389212024959

this paper gives mixed results inconclusive

here is one related to Quantum vacuum energy and the cosmological constant.
"The Quantum Vacuum and the Cosmological Constant Problem"
http://philsci-archive.pitt.edu/398/1/cosconstant.pdf

An exact scalar field inflationary cosmological model which solves Cosmological constant problem
and dark matter problem in addition to Horizon and Flatness problems and other problems of inflationary cosmology
http://arxiv.org/ftp/arxiv/papers/1112/1112.3005.pdf
"Quantum Vacuum Structure and Cosmology"
http://arxiv.org/abs/0909.2989
Stimulated creation of quanta during inflation and the observable universe
http://arxiv.org/abs/1106.4240
Hawking radiation from the cosmological horizon in a FRW universe
http://arxiv.org/abs/1007.4044
Electron-Positron Plasma Generation in a Magnetar Magnetosphere
http://arxiv.org/abs/0710.1000
 
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  • #172
forgot to add some articles on Bose-Einstein condensate, from the articles you can see the ground state relations. Frank mentioned absolute zero so I thought I'd include them.

http://www.theory.caltech.edu/~preskill/ph12c/ketterle-physicsworld.pdf simplified version

Basics of Bose-Einstein Condensation 102 page technical article (keep in mind Cambridge has done these tests and produced Bose-Einstein condensates for study.

http://arxiv.org/pdf/1105.4992.pdf
nobel prize for this process discussed in this paper
http://www.nobelprize.org/nobel_org...tion/symposia/physics/ncs-2001-1/ketterle.pdf
Making, probing and understanding Bose-Einstein condensates
http://arxiv.org/pdf/cond-mat/9904034.pdf

note the opening line...

" First, neutral atoms were cooled into the lowest energy state, thus exerting ultimate control over the motion and position of atoms, limited only by Heisenberg’s uncertainty" relation.

also keep in mind that as I'm not trying to form opinions, I didn't try to post papers of a particular view, so some of the articles may contradict one another. (for example the Basics of Bose_Einstein condensation, shows the numerous misinterpretations) also correlates to the article Timmdeeg posted
 
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  • #173
Frank Weil said:
I am fully aware of Andrew's (Jaffe) Chair and work in cosmology.

Then you are fully aware of the wrong Jaffre!

timmdeeg links to work by Robert Jaffe of MIT (and of Glimm and Jaffe and constructive qft fame), not to work by Andrew Jaffe of Imperial.
 
  • #174
George Jones said:
Then you are fully aware of the wrong Jaffre!

timmdeeg links to work by Robert Jaffe of MIT (and of Glimm and Jaffe and constructive qft fame), not to work by Andrew Jaffe of Imperial.

Thank you George!
Being English, I suppose I know better the work/papers of Andrew Jaffe/Penrose/Sir Michael Berry etc. This also includes those excellent theories by those,as yet, unknown or those people in the ascendency (as influence).
I am sure that you know, from my contributions to the forum, that I would never set out to offend or mislead...however that doesn't mean that I am not mislead by myself, and perhaps, my seemingly insular way of explaining things!
I think it was Mordred who understood this, in reply to Timmdeeg, when he said that I give/gave historical answers in reply to certain questions. I fully agree with Mordred, of course! I am no longer a youngster but am an 'ancient' academic who will never stop learning or discovering new 'truths' of the universe, either from the excellent contributions from the students and scholars of these pages, or from those in research and academia.
I will only put my oar in and comment, when it is appropriate to do so, and /or when the threads dry up a pace; probably due to night-time hours in America etc.
Anyway George, thanks for the heads-up and I shall now read MIT Jaffe's work!
Thank you.
 
  • #175
To add to Mordred's list above:
http://arxiv.org/abs/1311.5253v1
Enter in the box entitled: Search or Article-id. 'Cosmology'
Enter......: (Help | Advanced search. 'Abstracts'

As has been said before (Re: Mordred et al), this is a direction not a commendation.
 

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