Mark-- For some reason I have not received Axil's comments, however, the definition of coherence needs to be clarified.
I have always thought that coherence means that a quantum system exists of various matter with one quantum state and a single wave function. In a BEC there is only only wave function that exists at a time. That batch of matter--the BEC--acts like a single particle of matter. Its coupling is with other wave functions (associated with other matter or EM fields) that overlap and may or may not change its wave function. EM fields can be dynamic and moving field like in a photon or static fields like that associated with a group of static charges or coordinated moving charges. The idea of a "strong pumping mechanism" IMO means that the effective coupling happens when quantum state transitions (new wave functions) of the BEC change rapidly. Do these ideas differ from your concept. Bob ----- Original Message ----- From: MarkI-ZeroPoint To: vortex-l@eskimo.com Sent: Monday, December 29, 2014 8:55 PM Subject: [Vo]:Re: [Vo]:FYI: Strong light–matter coupling in two-dimensional atomic crystals Axil, A few of your statements may not be entirely true, depending on the prevailing conditions… “Coherence in these half matter half light systems is a function on the strength of the pumping mechanism. Coherence can occur at any temperature as long as the incoming pumping energy is strong enough. When we have a BEC fed with incoming pumped nuclear energy, very high temperatures can be reached.” The coherence that I’m referring to, of any significant scale, is highly unlikely in condensed matter above a few K. Inside a void in a crystal lattice, is entirely a different thing. If you’re referring to a BEC inside a void or microcavity, then I’m ok with the above statements… Assume you already have a BEC consisting of 100 Cs atoms… all of their wave functions are coherent. Now introduce a single photon of heat. That photon will be absorbed by *only a single atom*, thus, changing its wave function and vibrational amplitude. It’s wave function is now somewhat discordant with the remaining 99 atoms. From here, there are a couple of possibilities: 1) the single atom sheds a photon which is then absorbed by one of the other 99 atoms. This process can go on for however long until the photon gets shed and exits the BEC entirely. 2) if the heat energy is enough, the wave function is so discordant that the atom gets ejected from the BEC before it can shed the photon. 3) ? The more coherence between a set of waves, the stronger the coupling between them; the more discordant, the weaker the coupling. -mark iverson From: Axil Axil [mailto:janap...@gmail.com] Sent: Monday, December 29, 2014 8:30 PM To: vortex-l Subject: [Vo]:Re: [Vo]:FYI: Strong light–matter coupling in two-dimensional atomic crystals Casimir forces in a Plasma: Possible Connections to Yukawa Potentials http://arxiv.org/pdf/1409.1032v1.pdf Because of the vacuum energy, a plasma of virtual electron positron pairs exists in the space between two subatomic particles. Mesons form as excitons in this plasma. This is where pions come from in the nucleus that bind protons and neutrons together in a mutual pion mediated transmutation dance. I suspect the same plasma formation happens in larger cavities and is a direct result of the uncertainty principle in quantum mechanics, Coherence in these half matter half light systems is a function on the strength of the pumping mechanism. Coherence can occur at any temperature as long as the incoming pumping energy is strong enough. When we have a BEC feed with incoming pumped nuclear energy, very high temperatures can be reached. On Mon, Dec 29, 2014 at 10:53 PM, MarkI-ZeroPoint <zeropo...@charter.net> wrote: FYI: Article being referenced is at the bottom, however, I wanted to toss something out to The Collective first… One of the things that caught my eye in the article is the ‘room temperature’ condition… As we all know, atoms at room temp are vibrating like crazy since they contain the equivalent of 273degC of energy above their lowest state. Thus, ‘coherent’ states in condensed matter above absolute zero is almost never seen. The article’s experiment was done in material at room temp, so the observed behavior is a bit of a surprise. Perhaps what they have not yet thought about is that the ‘microcavities’ have no temperature, as I will explain below. This ties in with a point I tried to explain to Dr. Storms, and although I think he realizes my point had merit, he glossed right over it and went off on a different tangent. This was in a vortex discussion about 9 to 12 months ago. The point is this: The ‘temperature’ inside a ‘void’ in a crystal lattice is most likely that of the vacuum of space; i.e, absolute zero, or very close to it. Because, temperature is nothing more than excess energy imparted to atoms from neighboring atoms; atoms have temperature; space/vacuum does not. Without atoms (physical matter), you have no temperature. In a lattice void, if it is large enough (whatever that dimension is), there is NO ‘temperature’ inside since the void contains no atoms. If an atom diffuses into that void, it enters with whatever energy it had when it entered, so it has a temperature. At this time, I have not heard any discussion as to whether the atoms which make up the walls of the void shed IR photons which could get absorbed by an atom in the void and increase its temperature, however, would that atom want to immediately shed that photon to get back to its lowest energy level??? So voids in crystals likely provide an ideal environment for the formation of BECs. -mark iverson ARTICLE BEING REFERENCED Strong light–matter coupling in two-dimensional atomic crystals http://www.nature.com/nphoton/journal/v9/n1/full/nphoton.2014.304.html Abstract “Two-dimensional atomic crystals of graphene, as well as transition-metal dichalcogenides, have emerged as a class of materials that demonstrate strong interaction with light. This interaction can be further controlled by embedding such materials into optical microcavities. When the interaction rate is engineered to be faster than dissipation from the light and matter entities, one reaches the ‘strong coupling’ regime. This results in the formation of half-light, half-matter bosonic quasiparticles called microcavity polaritons. Here, we report evidence of strong light–matter coupling and the formation of microcavity polaritons in a two-dimensional atomic crystal of molybdenum disulphide (MoS2) embedded inside a dielectric microcavity at room temperature. A Rabi splitting of 46 ± 3 meV is observed in angle-resolved reflectivity and photoluminescence spectra due to coupling between the two-dimensional excitons and the cavity photons. Realizing strong coupling at room temperature in two-dimensional materials that offer a disorder-free potential landscape provides an attractive route for the development of practical polaritonic devices.”