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John Cox: on 1/25/21 at 21:25pm UTC, wrote "where work is the coherent component of energy radiated by the qubit." ...

Steve Dufourny: on 12/28/20 at 11:22am UTC, wrote Hi John, sorry for myn late answer, hope you are well, merry christmass...

John Cox: on 12/22/20 at 2:34am UTC, wrote Hi Steve, I'm always a bit puzzled by quantum-speak, but what I get is...

Steve Dufourny: on 12/20/20 at 18:16pm UTC, wrote Hi, this one is very interesting also. It is about the informations erasure...

Zeeya Merali: on 12/19/20 at 18:14pm UTC, wrote We analyze work extraction from a qubit into a wave guide (WG) acting as a...


John Cox: "Thanks Folks, it's nice to feel understood occasionally! But then I think..." in Towards the unification...

Steve Dufourny: "Thanks Stefan, it is nice, I am touched by your words, friendly" in Towards the unification...

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January 28, 2021

CATEGORY: Blog [back]
TOPIC: The energetic cost of work extraction by Alexia Auffeves [refresh]
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FQXi Administrator Zeeya Merali wrote on Dec. 19, 2020 @ 18:14 GMT
We analyze work extraction from a qubit into a wave guide (WG) acting as a battery, where work is the coherent component of the energy radiated by the qubit. The process is stimulated by a wave packet whose mean photon number (the battery's charge) can be adjusted. We show that the extracted work is bounded by the qubit's ergotropy, and that the bound is saturated for a large enough battery's charge. If this charge is small, work can still be extracted. Its amount is controlled by the quantum coherence initially injected in the qubit's state, that appears as a key parameter when energetic resources are limited. This new and autonomous scenario for the study of quantum batteries can be implemented with state-of-the-art artificial qubits coupled to WGs.

Ref: Monsel, Fellous Asiani, Huard, Auffèves, PHYSICAL REVIEW LETTERS 124, 130601 (2020)

Keywords: #quarantinethermo

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Steve Dufourny wrote on Dec. 20, 2020 @ 18:16 GMT
Hi, this one is very interesting also. It is about the informations erasure processes in fact in function of external fields. The spins seem essential . We have a maximum extractable work in fact and the hamiltonian seems essential too. All seems a question of motions of particles and in my model, the volumes, densities, rotations, motions become essential to correlate with this thermodynamics. I d like to speak about my idea, and the qutrits and the 3 aethers and these 3D spheres and their finite series , that becomes important for the energy if my equation is correct and also to reach the quantum computing mimating the foundamental objects of this universe. The couplings being the keys but for this we must have the correct system simulated. The thermalized system of these series in function of their properties with the cold and heat due to this matter not baryonic encoded imply spins different for the gravitational quantum fields , and a fith force also appearing due to this space vacuum of this DE. The protocols can be simulated and mathematically renormalised also , that will give the answers for the quantum computing in converging with the 3D spheres, the waves and fields and the works of these informations.

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John R. Cox replied on Dec. 22, 2020 @ 02:34 GMT
Hi Steve,

I'm always a bit puzzled by quantum-speak, but what I get is that a Qubit is a bit about to happen. Until it does, however, the coherent state is not necessarily a 'wave' in any organized form, perhaps the 'wave guide' is the observing system responsible for that outcome. So we are back to the primordial 'fuzziness' of the quantum realm. Turbulent or tepid, the physicality of raw energy may range in continuous variation of density in the near environs of the Qubit capable volume, and when it does decohere a spontaneous bit, then that 'photon number' is determinable in Planck units by the response of an external observing system.

Lacking a rationale that can be experimentally validated that would sufficiently penetrate the veil of the Transition Zone, and adequately describe what physically happens when an electron is photo-electrically ejected, or a discrete single photon is (instantaneously?) emitted at light velocity; we really can't say that the Qubit itself is discrete or that raw energy comes only in Planck unit packets. It is all fuzzy there-in. Happy Holidays, stay safe - jrc

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Steve Dufourny replied on Dec. 28, 2020 @ 11:22 GMT
Hi John, sorry for myn late answer, hope you are well, merry christmass also, I agree that the coherent state is more than this, in my theory the 3D spheres oscillate and are in vibrations and in motions, so we can insert deeper logic than just the fieds and waves. We retrun always indeed at what are really the foundamental objects and this origin philosophical of our universe. We just see the surfaces of problems. I consider personally qutrits to reach the quantum computing and so the logic in this line of reasoning is a deeper ones than our photons and electrons only , if the space vacuum of this DE is the main codes and is an energy and if the two others fuels , the photons and cold dark matter merge with this space to create this reality , so we need to consider 3 systems mainly for the informations. That implies a kind of convergences with these qubits and a bridge, but the big question is how to arrive to create this mechanism. Thanks , friendly

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John R. Cox replied on Jan. 25, 2021 @ 21:25 GMT
"where work is the coherent component of energy radiated by the qubit."

Okay... stated like that, the Work Function can be rapidity of change of slope of a curve not to be conflated with 'rate of change'. Rate of change can be plotted as a cosine transformation independent of a time parameter whereas rapidity of change as typically applied in analysis such as at CERN in the detection of particles decohering from an energy 'jet' is both a rate of change and a time dependent relativistic bound. This would all, then, be consistent with QFT wherein the relativistic component is limited to a degree of freedom in the parameter of Momentum being relativistic mass without incorporating time or space dilation.

If one were to accept inclusion of dilation into the model, one might argue that the shape of rapidity of the work extracted in the wave guide as measured by the ballistic response of the detection observing system to any one of the photon number of particulate photons, would naturally evolve in the time parameter of the coherent energy radiated by the qubit(s) slowing from light velocity at an exponential rate consistent to the observed generalized rate of change of intensity in the Reactive Region of the Transition Zone of a reception antennae. Neither wave or particle can be assumed to be stopped instantaneously, only its leading edge. The rest of its discrete volumetric mass/energy quantity would 'pile up' on itself.

The energetic cost of work extraction is akin to the play in croquet where you can "send" your opponent's ball if your shot hits it and both come to rest within a mallet handle distance of separation; by placing your ball against the opponent's and with your toe holding your ball in place, giving it a whack with the mallet!

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