The Cosmological Constant: a New Law

[Tormod]

Reply # 46, do virtual particles appear every where in the universe and if so do they also appear inside the earth or even my body?

 

AFAIK, they can appear anywhere. You wouldn't notice them, though. The effect of these virtual particles is extremely small. IT is however measured - it is known as the Casimir effect which occurs as an attractive force between two sheets of metal placed in a vacuum.

 

http://physicsweb.org/articles/world/15/9/6

[spennithorne]

By strict definition, the cosmological constant, conventionally denoted Omega, is a parameter describing the energy density of the vacuum, and a potentially important contributor to the dynamical history of the universe. When we speak today of dark energy this vacuum component is what is being spoken about. The energy density in a cosmological constant is a property of spacetime itself, and under ordinary circumstances is the same everywhere. However, based upon observational evidence this does not seem to be the full case since observationally dark energy seems to dominate over large distances and has little effect in short distances. So some mechanism, yet properly understood, makes it so that it is not the same everywhere.

 

Cosmologists describe this expansion by defining a scale factor R(t), which specifies the relative distance of galaxies as a function of time. The behavior of the scale factor is governed by the curvature of space, which can be positive, negative, or zero, and the average energy density of the universe. There are actually three different omega values. One is the value for all matter of the normal type, another is for dark matter, and the third is the one we term the cosmological constant. Dark matter works just like regular matter and produces a gravitational field. It just cannot be viewed directly by any current means. Dark energy(the cosmological constant) works opposite of gravity because it is based upon pressure and causes things to expand. In General Relativity, any form of energy affects the gravitational field, so the vacuum energy becomes a crucial ingredient countering gravity itself and helps determine the actual shape of spacetime.

A question---Since it is now recently concluded that the cosmos is not only expanding, but is expanding at an accelerating rate, does that mean that the Cosmological Constant is not constant, but is instead increasing?

 

And what is it about Dark Energy that would cause acceleration (rather than entropic dissipation) in the rate of cosmic dispersal?

[infamous]

Sorry, to what?

Tormod, I believe Little Bangs question was in post #46.

 

Do virtual particles appear everywhere in the known universe, in the earth, in our bodies, ect.

 

Drat! by the time I got this posted the answer had already been given. My computer is so slow, it is really maddening.

[Tormod]

Tormod, I believe Little Bangs question was in post #46.

 

Do virtual particles appear everywhere in the known universe, in the earth, in our bodies, ect.

 

Yes, and I replied to that already...

[Little Bang]

Tormod, if this is true it looks to me like large numbers of virtual particles inside stars would be converted to real particles that would annihilate each other releasing high energy photons. I wonder if there is any significance in this?

[infamous]

Yes, and I replied to that already...

Yes Tormod, I was just editing my last post. My computer responds so slow that somebody always beats me to it.

[infamous]

Tormod, if this is true it looks to me like large numbers of virtual particles inside stars would be converted to real particles that would annihilate each other releasing high energy photons. I wonder if there is any significance in this?

 

Little Bang, what your failing to consider is there was in fact no increase in total energy. The energy it took to create the virtual particles was already there, resulting in the electron positron pair formation. As they reunit, the energy is just returned to the vacuum.

[Little Bang]

True, the conservation of energy is maintained, but the fact remains that two high energy photons are created.

[infamous]

True, the conservation of energy is maintained, but the fact remains that two high energy photons are created.

 

Very true Little Bang, however, if you follow the sequence backwards you will understand that the photons were generated by the electron positron pair. Going backwards still farther, the electron positron pair were generated by an equivalent energy present in the vacuum. So really the star has not gained any energy as a result. There is within the vacuum itself, irrespective of the energy present within the star, an energy density which gives rise to these virtual particles. So weather in the presence of a star or not the energy density will give rise to the electron positron pair which in turn will return it's self to the vacuum. The final energy output of the star has not changed as a result to this virtual process. There are exceptions whereby a small amount of energy may be added, however, this added energy must eventually be returned to the vacuum no matter how long lived the exchange was permitted to last.

[justforfun]

Remember, coldcreation, that "A beginning is the time for taking the most delicate care that the balamces are correct." - Frank Herbert "Dune"

[coldcreation]

Remember, coldcreation, that "A beginning is the time for taking the most delicate care that the balamces are correct." - Frank Herbert "Dune"

 

All is just for fun in science fiction (Dune, I fell asleep about 1/4 of the way through the movie, and never bothered to open the book. It has sat on my shelf from the beginning).

Joviality is a game of children.

[coldcreation]

Question coldc, do virtual particles appear every where in the universe and if so do they also appear inside the earth or even my body?

 

Why yes little bang, thrice yes, they do... The questions I ask you now are (1) what good is a particle-virtual-particle pair production if they are so short lived? (2) Are they either particles or waves, both or non of the above? (3) Is there any residual effect on the vacuum, and if not, why would nature even bother with them. (4) And finally, what drives them, i.e., where does their energy come from to appear then disappear?

 

Please don’t write a textbook history of the particles (I can look them up again myself), I’d like to know what you objectively think based on your innate experience...

 

 

I like the idea of virtual particles appearing and disappearing in the vacuum everywhere and all the time. But I see things from a more simple, more pragmatic perspective. The activity occurring in space is actually well know. General relativity GR, quantum mechanics QM and the third law of thermodynamics explain the vacuum as containing a residual energy, a minimum energy, an irreducible kinetic energy. The result according to Herr Einstein “There is no such thing as empty space, i.e. a space without field. Space-time does not claim existence on its own, but as a structural quality of the field.”

 

In agreement with QM, there are irreducible zero point energy fluctuations ZPE, ZPF in the vacuum. Without this ground energy flux there would exist only an expanse of empty space and time where nothing would ever change, where nothing would ever convene, assemble or organize itself to form anything larger than a fundamental particle, let alone the nebulous islands of spiral elliptical and spherical configurations that populate the entire cosmos at the present time. I highly doubt, however, that a quantum fluctuation could have spawned the entire universe.

 

According to the physicist that currently resides in the Cambridge chair formerly held by Isaac Newton (but with wheels); “the uncertainty principle means that even “empty” space is filled with pairs of virtual particles and antiparticles.” He persists…”These pairs would have an infinite amount of energy and, therefore…they would have an infinite amount of mass. There gravitational attraction would thus curve up the universe to infinitely small size.” (Hawking 1988 p. 157). This is more wishful thinking than anything else.

 

And the third law, stating the impossibility of attaining absolute zero temperature. This result is easily explained through the idea that as temperature tends to absolute zero all waves (or particles) will remain in their lowest energy state. And so there is always kinetic energy, motion.

 

So to answer your queries little bang. Maybe you see virtual particles, I see vacuum energy fluctuations. Yes then, vacuum fluctuations do occur everywhere in the universe. They do occur inside massive bodies in the space between particle, atoms, molecules and so on. Yes vacuum energy flux is occurring inside your physical body. I will add with certainty too that vacuum fluctuations are at work deep in your decision making faculties. This is why the chapter entitle Quantum Relativity of Consciousness was written last year, and partly posted on these pages. I see now we find common ground on certain issues (that is of course if your question reflects the tendency of your thought, which I am certain they do).

 

Indeed the particle-virtual particle production-destruction process does not appear identical to vacuum energy. Both particles and virtual particles contribute identically to the energy of the vacuum, however, they contribute with opposite signs! So the net contribution of fluctuations in the vacuum is zero (I think. I would have to research that further). We do not observe zero vacuum fluctuations in the real world. One can only assume then that symmetry is spontaneously broken, meaning vacuum energy contributions will no longer cancel.

 

It might be safe to write that firm conclusions can be deduced now that general relativity and quantum mechanics (with the cosmological constant) is better understood than at the time Dirac had created his seething image. See if this works: instead of ...–1, 0, +1.... Try ...1, 0, 1...

 

Given that the cosmological constant overlaps both quantum mechanics and general relativity, it is natural to think that a solution to unification is near if not here, and that a clear description of lambda will resolve discrepancies that have plagued physics for decades (or centuries, depending how far back one considers). Although an ultimate theory has not been available to date, forward strides have been made in understanding the cosmological constant in the framework of contemporary cosmology (and in physics generally).

 

In the final analysis, it may sound paradoxical that in an age of high energy physics, M-theory, string theory, supergravity, supersymmetry, loop-quantum gravity and an entire zoo of ultra-heavy particles, supermassive black holes and 21 dimensions that something as simple as the cosmological constant solves all the problems, and does so in the range of very low temperature, low energy physics.

 

The list of implications is extensive. Here is just one: the thermal history of the universe is from extremely close to absolute zero, to the observed 2.726 Kelvin. This means that all experiments realized here on earth that take place below 2.726 K are common place in the universe: states of matter called Bose-Einstein condensates BEC, superfluidity, etc.

 

Here is one more bonus implication to chew on: material creation of protons, neutrons, electrons (ultimately hydrogen) takes place in the vacuum close (extremely so) to the absolute zero of temperatures: not in a big bang, not in a series of little bangs or little whimpers, but in a process of vacuum fluctuations (this subject too will open the thread called Cold Creation: the theory, soon visible online). Eventually experiments will be able to determine the veracity of this prospect. But for now, and foremost, it is the veracity of lambda the subject of scrutiny.

 

Einstein’s “greatest blunder” was to have discarded the cosmological constant...

 

coldcreation

[Little Bang]

infamous, I'm not saying there is any gain or loss, I'm only guessing (because I have no way to prove it) that a large proportion of the photons produced by a staris by this process. Virtual particles are not directly observable except were the energy density is high enough to make them part of our reality. This to me would mean that 99.9----------% of all virtual particles that become real in our universe occurs in stars. This doesn't mean anything it's just a thought.

[coldcreation]

infamous, I'm not saying there is any gain or loss, I'm only guessing (because I have no way to prove it) that a large proportion of the photons produced by a staris by this process. Virtual particles are not directly observable except were the energy density is high enough to make them part of our reality. This to me would mean that 99.9----------% of all virtual particles that become real in our universe occurs in stars. This doesn't mean anything it's just a thought.

 

Little Bang, if virtual particles is the vaccum have anything to do with the cosmological constant (apparently they do) then I fail to see how they manifest themselve only in dense regions. Why not everywhere. And if the answer is that virtual particles are not real, i.e., they "become real in our universe" only in stellar activity, then why are they important in space, in the vacuum.

 

I have a feeling that had Dirac not introduced the concept someone else would have done so. The mirror symmetry, even if brocken spontaneously (in stars as you imply), seems logical. But still something is amiss.

 

It is now supposed that had Einstein not introduced the term into general relativity that it would have surfaced eventually regardless. A case and point, that when science is ready to make a discovery, nothing can stop it. Paradoxically, it is within the frothy realm of quantum mechanics that empty space is a seething ‘sea’ of energetic virtual particles.

 

Moreover, the energy associated with the quantum vacuum of space has the same form as the cosmological constant invented ad hoc by Einstein. It is hoped that some symmetry principle could make lamda disappear once and for all, but then, one would still be placed in the awkward position of having to explain the 1998 SNe Ia measurements that make the universe look like it's expansion is accelerating. Before 1998, it looked like a bad idea; it now looks like a mad idea.

 

cryogenicreation

[Little Bang]

I can't compete coldc. Your logic overwhelms me.

[coldcreation]

I can't compete coldc. Your logic overwhelms me.

 

Forget about white voids. I only told you that story because black holes are equally whimsical. You should forget about them too. There are so many more interesting things that are real in nature that still need to be looked at with the inquisitive eye...

cc

[coldcreation]

Remember, coldcreation, that "A beginning is the time for taking the most delicate care that the balamces are correct." - Frank Herbert "Dune"

 

 

If the clocks were ticking backwards, going back in time, the entropy of the universe decreases until it reaches or nearly reaches zero. But that does not imply that zero would be reached at some equilibrium state a beginning in time.

 

The entropy of the universe could continue decreasing as time tends towards minus infinity without therefore attaining the zero value.

 

Ilya Prigogine, a prominent expert in the field, expresses the view-point that ”the laws of physics describe an idealized world that is quite different from the unstable, evolving world in which we live…we can no longer associate the arrow of time only with an increase of disorder. Recent developments in nonequilibrium physics and chemistry point in the opposite direction. They show unambiguously that the arrow of time is a source of order…Irreversibility leads to both order and disorder…they do not correspond to approximations added to the basic laws. Irreversible processes play a fundamental constructive role in nature.” (1996, p. 26)

 

Prigogine wrote on page 184: “From the start, the universe would have appeared as a thermodynamic system far from equilibrium, with instabilities and bifurcations.” With due respect, we will show that Prigogine’s view is untenable. Entropy generally increases with time. If we were to turn the clocks backwards, entropy decreases to a minimum value close to, if not equal to zero. A universe far-from-equilibrium (at the outset) would already have positive entropy production. The solution has to be, as one tends to minus infinity, the universe approaches equilibrium without ever reaching it.

 

The cosmological constant, lambda, always stays the same. It is a universal constant.

 

coldcreation