Re: [Vo]:Stimulated emission and Pre-Quantum Physics
Time is absolute In quantum mechanics like it is in Newtonian mechanics. However, since Newtonian mechanics does not allow for non-locality, it could be that the Newtonian sense of absolute time (N-Time) differs subtley from the Quantum Mechanical sense of absolute time (Q-Time). Perhaps the hidden variable is some form of information that resides in Q-Time that is not present in N-Time. Harry On Fri, Apr 29, 2022 at 3:14 PM Vibrator ! wrote: > > here is an example > > Absorption and Stimulated Emission by a Thin Slab Obeying the Lorentz > > Oscillator Model > > It's a quantitative formulation from classical first principles, sans > Schrodinger.. whereas the wave equation approximates the time evolution of > the wavefunction; you could describe a stimulated emission / absorption mode > as playing the predictability of wavefunction's evolution by constantly > resetting it at a fixed freq.. or you could probably describe the behaviour > in terms of QED and Feynman diagrams too i expect, all complimentarily w/o > conflict. You can describe orbital transition energies classically / > relativistically, or Lenz's law in terms of relativistic self-interaction of > a current loop invoking length contraction / time dilation, or in terms of > time-conservation of ambient quantum momentum, charge and energy.. the whole > point about zombie-cat-boxes being that they're an over-extrapolated > conclusion from what is only a formal approximation; atoms and photons are > obviously real, but is the wavefunction? So there's no real dichotomy.. all > roads lead to Rome, we know the SM's incomplete and we're not seeing all the > pieces yet, but the realism / objectivism debate is divided along more > fundamental lines on the nature of causal determinism and the outstanding > possibility (if not logical prerequisite) of non-local hidden variables.. > which in turn segues into philosophical debate re. distinctions between > 'indeterminability' as an inevitable consequence of conservation and finite > nature of quantum information (ie. per Zeilinger et al), versus the > nihilistic anarchy of objective indeterminism; you can guess which side of > the fence i'm on (tho not a Bohm fanatic; pilot waves or some variation, > perhaps.. but his later metaphysics stuff i don't subscribe to). > > The classic DSE using an electron gun and phosphor-plated screen has to > remain the benchmark gold-standard for demonstrating the limits of classical > physics though - ie. it cannot explain how particles / waves self-interact > even when their transits are separated out in time. If not for this singular > crazy (dumbfounding!) result, we wouldn't be in a situation where most > physicists are ready to accept such an oxymoronic imposition as 'acausal > determinants'.. but in for a penny, in for a pound eh.. > >
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
"There's still a good bit of unfinished business with certain 18th-century breakthroughs that've languished.." That is correct. Physics students are misinformed by the physics establishment about physics history, especially missing out most of stuff in 18th century. -- Original Message -- From: "Vibrator !" To: vortex-L@eskimo.com Sent: Friday, 29 Apr, 22 At 23:43 Subject: Re: [Vo]:Stimulated emission and Pre-Quantum Physics > So progression from 18th century theory of Boscovich to modern physics Fascinating, i was unaware of Boscovich's contributions, great first-principle reasoning though.. There's still a good bit of unfinished business with certain 18th-century breakthroughs that've languished, but don't get me started..
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
> So progression from 18th century theory of Boscovich to modern physics Fascinating, i was unaware of Boscovich's contributions, great first-principle reasoning though.. There's still a good bit of unfinished business with certain 18th-century breakthroughs that've languished, but don't get me started..
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
Harry I think of it as precursor to Bohm's pilot wave theory - particles influenced by waves. Boscovich's theory is particles influenced by fields; and a disturbance in a field would be a wave. -- Original Message -- From: "H LV" To: vortex-l@eskimo.com Sent: Friday, 29 Apr, 22 At 19:38 Subject: Re: [Vo]:Stimulated emission and Pre-Quantum Physics Did Boscovich subscribe to a wave or a particle view of light? I wonder if electrons are "elementary points" and protons are "first order particles" in Boscosvich's scheme. https://youtu.be/w1vi0yk7BvU?t=248 <https://youtu.be/w1vi0yk7BvU?t=248> harry On Fri, Apr 29, 2022 at 8:28 AM ROGER ANDERTON mailto:r.j.ander...@btinternet.com> > wrote: Also (i) Boscovich theory led to Quantum theory -> https://www.youtube.com/watch?v=w1vi0yk7BvU <https://www.youtube.com/watch?v=w1vi0yk7BvU> (ii) Einstein working from Boscovich theory -> https://iopscience.iop.org/article/10.1088/1742-6596/2197/1/012002/meta <https://iopscience.iop.org/article/10.1088/1742-6596/2197/1/012002/meta> So progression from 18th century theory of Boscovich to modern physics -- Original Message -- From: "H LV" mailto:hveeder...@gmail.com> > To: vortex-l@eskimo.com <mailto:vortex-l@eskimo.com> Sent: Friday, 29 Apr, 22 At 13:19 Subject: Re: [Vo]:Stimulated emission and Pre-Quantum Physics On Thu, Apr 28, 2022 at 5:44 PM Vibrator ! <mailto:mrvibrat...@gmail.com> > wrote: I have been doing more reading about the history of stimulated emission. Einstein formally introduced a quantum version of the concept in 1917. Therefore you might think that it is only possible in a quantum theoretical context. However, subsequent mathematical work has shown that a form of stimulated emission can also arise in a classical (pre-quantum) setting when a suitable model of the atom is used. The key point about stimulated emission is that it exploits the suspension of superposition exclusion to enable an aggregate system to cohere under a unitary wavefuntion; the corollary effect being coherent absorption, such that the initial plasma system can be classically described right up to the population inversion: from which point all electrons are bouncing between peak energy and stable bottom, emitting and absorbing essentially the same photons in sync.. ..so the quantum / classical threshold there is Pauli exclusion; the spontaneous photomultiplication resulting from collective coherence of the electron population is a pretty fundamental kind of 'resonance', not your average harmonic oscillator. On this key point about coherent absorption as well as emission, see Green at al "Limiting photovoltaic monochromatic light conversion efficiency" 2001, noting that in PV cells for which recombination is mainly radiative, a stimulated emission regime could take efficiency arbitrarily close to the Carnot limit; his team down in Oz are currently up to ~70% - again, for monochromatic (basically laser) light - with increasing applications in ie. wireless power transmission, electrical isolation / firewalling etc., and obvs much greater range (albeit limited to LoS) than classical inductive transmission techniques. A stimulated emission mode / regime is an inherently quantum-classical system, a unique means of corralling quantum systems distinct from Faraday and Maxwell et al; the system's propensity to begin lasing a direct consequence of the quantisation of energy & momentum: in the tensioned 'population inversion' state, ideally at least, a single photon of further input energy will inevitably trigger a cascade of absorption and emission because there's nowhere else for this conserved quantised energy to go, ie. further input energy catalyses a cyclic phase transition between high and low-energy states, because the transitions are quantised, and because a whole bunch of fermions are behaving as a kind of extended quasi-boson, holding the same quantum-energy states at the same time. It's that force-feedback dynamic, like a turbine, generating this low-entropy livewire state of perfect photoelectric synchrony.. coherent emission AND absorption, en masse.. On a bit of a tangent perhaps, but in his later years GC Huth posited that the retinal cells of the fovea may form a kind of phase-conjugate mirror, which may have thought-provoking implications for ie. the nature of eye contact between sentients, optic nerves essentially being extensions of cortex: what if electrons in remote rhodopsin discs are entangled by the same photons? 'A twinkle in the eye'.. 'windows on the soul'.. (woo-wavy hands) Interesting read. Did you read Bill's post? There are many classical systems which exhibit stimulated emission which don't depend on quantum theory. Radiation theorists of the second half of the 19th century appeared to dislike t
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
in add: http://hyperphysics.phy-astr.gsu.edu/hbase/quantum/schr.html IE. equivalent, not conflicting..
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
> here is an example > Absorption and Stimulated Emission by a Thin Slab Obeying the Lorentz > Oscillator Model It's a quantitative formulation from classical first principles, sans Schrodinger.. whereas the wave equation approximates the time evolution of the wavefunction; you could describe a stimulated emission / absorption mode as playing the predictability of wavefunction's evolution by constantly resetting it at a fixed freq.. or you could probably describe the behaviour in terms of QED and Feynman diagrams too i expect, all complimentarily w/o conflict. You can describe orbital transition energies classically / relativistically, or Lenz's law in terms of relativistic self-interaction of a current loop invoking length contraction / time dilation, or in terms of time-conservation of ambient quantum momentum, charge and energy.. the whole point about zombie-cat-boxes being that they're an over-extrapolated conclusion from what is only a formal approximation; atoms and photons are obviously real, but is the wavefunction? So there's no real dichotomy.. all roads lead to Rome, we know the SM's incomplete and we're not seeing all the pieces yet, but the realism / objectivism debate is divided along more fundamental lines on the nature of causal determinism and the outstanding possibility (if not logical prerequisite) of non-local hidden variables.. which in turn segues into philosophical debate re. distinctions between 'indeterminability' as an inevitable consequence of conservation and finite nature of quantum information (ie. per Zeilinger et al), versus the nihilistic anarchy of objective indeterminism; you can guess which side of the fence i'm on (tho not a Bohm fanatic; pilot waves or some variation, perhaps.. but his later metaphysics stuff i don't subscribe to). The classic DSE using an electron gun and phosphor-plated screen has to remain the benchmark gold-standard for demonstrating the limits of classical physics though - ie. it cannot explain how particles / waves self-interact even when their transits are separated out in time. If not for this singular crazy (dumbfounding!) result, we wouldn't be in a situation where most physicists are ready to accept such an oxymoronic imposition as 'acausal determinants'.. but in for a penny, in for a pound eh..
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
Did Boscovich subscribe to a wave or a particle view of light? I wonder if electrons are "elementary points" and protons are "first order particles" in Boscosvich's scheme. https://youtu.be/w1vi0yk7BvU?t=248 harry On Fri, Apr 29, 2022 at 8:28 AM ROGER ANDERTON wrote: > Also > > (i) Boscovich theory led to Quantum theory -> > https://www.youtube.com/watch?v=w1vi0yk7BvU > > > (ii) Einstein working from Boscovich theory -> > https://iopscience.iop.org/article/10.1088/1742-6596/2197/1/012002/meta > > > So progression from 18th century theory of Boscovich to modern physics > > > > -- Original Message -- > From: "H LV" > To: vortex-l@eskimo.com > Sent: Friday, 29 Apr, 22 At 13:19 > Subject: Re: [Vo]:Stimulated emission and Pre-Quantum Physics > > > On Thu, Apr 28, 2022 at 5:44 PM Vibrator ! wrote: > >> > I have been doing more reading about the history of stimulated >> > emission. Einstein formally introduced a quantum version of the concept >> in >> > 1917. >> > Therefore you might think that it is only possible in a quantum >> theoretical >> > context. However, subsequent mathematical work has shown that a form of >> > stimulated emission can also arise in a classical (pre-quantum) setting >> > when a suitable model of the atom is used. >> >> The key point about stimulated emission is that it exploits the >> suspension of superposition exclusion to enable an aggregate system to >> cohere under a unitary wavefuntion; the corollary effect being coherent >> absorption, such that the initial plasma system can be classically >> described right up to the population inversion: from which point all >> electrons are bouncing between peak energy and stable bottom, emitting and >> absorbing essentially the same photons in sync.. >> >> ..so the quantum / classical threshold there is Pauli exclusion; the >> spontaneous photomultiplication resulting from collective coherence of the >> electron population is a pretty fundamental kind of 'resonance', not your >> average harmonic oscillator. >> >> On this key point about coherent absorption as well as emission, see >> Green at al "Limiting photovoltaic monochromatic light conversion >> efficiency" 2001, noting that in PV cells for which recombination is mainly >> radiative, a stimulated emission regime could take efficiency arbitrarily >> close to the Carnot limit; his team down in Oz are currently up to ~70% - >> again, for monochromatic (basically laser) light - with increasing >> applications in ie. wireless power transmission, electrical isolation / >> firewalling etc., and obvs much greater range (albeit limited to LoS) than >> classical inductive transmission techniques. >> >> A stimulated emission mode / regime is an inherently quantum-classical >> system, a unique means of corralling quantum systems distinct from Faraday >> and Maxwell et al; the system's propensity to begin lasing a direct >> consequence of the quantisation of energy & momentum: in the tensioned >> 'population inversion' state, ideally at least, a single photon of further >> input energy will inevitably trigger a cascade of absorption and emission >> because there's nowhere else for this conserved quantised energy to go, ie. >> further input energy catalyses a cyclic phase transition between high and >> low-energy states, because the transitions are quantised, and because a >> whole bunch of fermions are behaving as a kind of extended quasi-boson, >> holding the same quantum-energy states at the same time. >> >> It's that force-feedback dynamic, like a turbine, generating this >> low-entropy livewire state of perfect photoelectric synchrony.. coherent >> emission AND absorption, en masse.. >> >> On a bit of a tangent perhaps, but in his later years GC Huth posited >> that the retinal cells of the fovea may form a kind of phase-conjugate >> mirror, which may have thought-provoking implications for ie. the nature of >> eye contact between sentients, optic nerves essentially being extensions of >> cortex: what if electrons in remote rhodopsin discs are entangled by the >> same photons? 'A twinkle in the eye'.. 'windows on the soul'.. (woo-wavy >> hands) >> > > Interesting read. > Did you read Bill's post? There are many classical systems which exhibit > stimulated emission which don't depend on quantum theory. Radiation > theorists of the second half of the 19th century appeared to dislike the > notion of anything resembling stimulated or induced emission even though it > did not violate the laws of physics. Perhaps the concept of stimulated or > induced emission was in conflict with Victorian sensibilities. > > here is an example > Absorption and Stimulated Emission by a Thin Slab Obeying the Lorentz > Oscillator Model > https://iopscience.iop.org/article/10.7567/1347-4065/ab2cc6 > > Harry > >
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
Also (i) Boscovich theory led to Quantum theory -> https://www.youtube.com/watch?v=w1vi0yk7BvU (ii) Einstein working from Boscovich theory -> https://iopscience.iop.org/article/10.1088/1742-6596/2197/1/012002/meta So progression from 18th century theory of Boscovich to modern physics -- Original Message -- From: "H LV" To: vortex-l@eskimo.com Sent: Friday, 29 Apr, 22 At 13:19 Subject: Re: [Vo]:Stimulated emission and Pre-Quantum Physics On Thu, Apr 28, 2022 at 5:44 PM Vibrator ! <mailto:mrvibrat...@gmail.com> > wrote: I have been doing more reading about the history of stimulated emission. Einstein formally introduced a quantum version of the concept in 1917. Therefore you might think that it is only possible in a quantum theoretical context. However, subsequent mathematical work has shown that a form of stimulated emission can also arise in a classical (pre-quantum) setting when a suitable model of the atom is used. The key point about stimulated emission is that it exploits the suspension of superposition exclusion to enable an aggregate system to cohere under a unitary wavefuntion; the corollary effect being coherent absorption, such that the initial plasma system can be classically described right up to the population inversion: from which point all electrons are bouncing between peak energy and stable bottom, emitting and absorbing essentially the same photons in sync.. ..so the quantum / classical threshold there is Pauli exclusion; the spontaneous photomultiplication resulting from collective coherence of the electron population is a pretty fundamental kind of 'resonance', not your average harmonic oscillator. On this key point about coherent absorption as well as emission, see Green at al "Limiting photovoltaic monochromatic light conversion efficiency" 2001, noting that in PV cells for which recombination is mainly radiative, a stimulated emission regime could take efficiency arbitrarily close to the Carnot limit; his team down in Oz are currently up to ~70% - again, for monochromatic (basically laser) light - with increasing applications in ie. wireless power transmission, electrical isolation / firewalling etc., and obvs much greater range (albeit limited to LoS) than classical inductive transmission techniques. A stimulated emission mode / regime is an inherently quantum-classical system, a unique means of corralling quantum systems distinct from Faraday and Maxwell et al; the system's propensity to begin lasing a direct consequence of the quantisation of energy & momentum: in the tensioned 'population inversion' state, ideally at least, a single photon of further input energy will inevitably trigger a cascade of absorption and emission because there's nowhere else for this conserved quantised energy to go, ie. further input energy catalyses a cyclic phase transition between high and low-energy states, because the transitions are quantised, and because a whole bunch of fermions are behaving as a kind of extended quasi-boson, holding the same quantum-energy states at the same time. It's that force-feedback dynamic, like a turbine, generating this low-entropy livewire state of perfect photoelectric synchrony.. coherent emission AND absorption, en masse.. On a bit of a tangent perhaps, but in his later years GC Huth posited that the retinal cells of the fovea may form a kind of phase-conjugate mirror, which may have thought-provoking implications for ie. the nature of eye contact between sentients, optic nerves essentially being extensions of cortex: what if electrons in remote rhodopsin discs are entangled by the same photons? 'A twinkle in the eye'.. 'windows on the soul'.. (woo-wavy hands) Interesting read. Did you read Bill's post? There are many classical systems which exhibit stimulated emission which don't depend on quantum theory. Radiation theorists of the second half of the 19th century appeared to dislike the notion of anything resembling stimulated or induced emission even though it did not violate the laws of physics. Perhaps the concept of stimulated or induced emission was in conflict with Victorian sensibilities. here is an example Absorption and Stimulated Emission by a Thin Slab Obeying the Lorentz Oscillator Model https://iopscience.iop.org/article/10.7567/1347-4065/ab2cc6 <https://iopscience.iop.org/article/10.7567/1347-4065/ab2cc6> Harry
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
On Thu, Apr 28, 2022 at 5:44 PM Vibrator ! wrote: > > I have been doing more reading about the history of stimulated > > emission. Einstein formally introduced a quantum version of the concept > in > > 1917. > > Therefore you might think that it is only possible in a quantum > theoretical > > context. However, subsequent mathematical work has shown that a form of > > stimulated emission can also arise in a classical (pre-quantum) setting > > when a suitable model of the atom is used. > > The key point about stimulated emission is that it exploits the suspension > of superposition exclusion to enable an aggregate system to cohere under a > unitary wavefuntion; the corollary effect being coherent absorption, such > that the initial plasma system can be classically described right up to the > population inversion: from which point all electrons are bouncing between > peak energy and stable bottom, emitting and absorbing essentially the same > photons in sync.. > > ..so the quantum / classical threshold there is Pauli exclusion; the > spontaneous photomultiplication resulting from collective coherence of the > electron population is a pretty fundamental kind of 'resonance', not your > average harmonic oscillator. > > On this key point about coherent absorption as well as emission, see Green > at al "Limiting photovoltaic monochromatic light conversion efficiency" > 2001, noting that in PV cells for which recombination is mainly radiative, > a stimulated emission regime could take efficiency arbitrarily close to the > Carnot limit; his team down in Oz are currently up to ~70% - again, for > monochromatic (basically laser) light - with increasing applications in ie. > wireless power transmission, electrical isolation / firewalling etc., and > obvs much greater range (albeit limited to LoS) than classical inductive > transmission techniques. > > A stimulated emission mode / regime is an inherently quantum-classical > system, a unique means of corralling quantum systems distinct from Faraday > and Maxwell et al; the system's propensity to begin lasing a direct > consequence of the quantisation of energy & momentum: in the tensioned > 'population inversion' state, ideally at least, a single photon of further > input energy will inevitably trigger a cascade of absorption and emission > because there's nowhere else for this conserved quantised energy to go, ie. > further input energy catalyses a cyclic phase transition between high and > low-energy states, because the transitions are quantised, and because a > whole bunch of fermions are behaving as a kind of extended quasi-boson, > holding the same quantum-energy states at the same time. > > It's that force-feedback dynamic, like a turbine, generating this > low-entropy livewire state of perfect photoelectric synchrony.. coherent > emission AND absorption, en masse.. > > On a bit of a tangent perhaps, but in his later years GC Huth posited that > the retinal cells of the fovea may form a kind of phase-conjugate mirror, > which may have thought-provoking implications for ie. the nature of eye > contact between sentients, optic nerves essentially being extensions of > cortex: what if electrons in remote rhodopsin discs are entangled by the > same photons? 'A twinkle in the eye'.. 'windows on the soul'.. (woo-wavy > hands) > Interesting read. Did you read Bill's post? There are many classical systems which exhibit stimulated emission which don't depend on quantum theory. Radiation theorists of the second half of the 19th century appeared to dislike the notion of anything resembling stimulated or induced emission even though it did not violate the laws of physics. Perhaps the concept of stimulated or induced emission was in conflict with Victorian sensibilities. here is an example Absorption and Stimulated Emission by a Thin Slab Obeying the Lorentz Oscillator Model https://iopscience.iop.org/article/10.7567/1347-4065/ab2cc6 Harry
[Vo]:Stimulated emission and Pre-Quantum Physics
> I have been doing more reading about the history of stimulated > emission. Einstein formally introduced a quantum version of the concept in > 1917. > Therefore you might think that it is only possible in a quantum theoretical > context. However, subsequent mathematical work has shown that a form of > stimulated emission can also arise in a classical (pre-quantum) setting > when a suitable model of the atom is used. The key point about stimulated emission is that it exploits the suspension of superposition exclusion to enable an aggregate system to cohere under a unitary wavefuntion; the corollary effect being coherent absorption, such that the initial plasma system can be classically described right up to the population inversion: from which point all electrons are bouncing between peak energy and stable bottom, emitting and absorbing essentially the same photons in sync.. ..so the quantum / classical threshold there is Pauli exclusion; the spontaneous photomultiplication resulting from collective coherence of the electron population is a pretty fundamental kind of 'resonance', not your average harmonic oscillator. On this key point about coherent absorption as well as emission, see Green at al "Limiting photovoltaic monochromatic light conversion efficiency" 2001, noting that in PV cells for which recombination is mainly radiative, a stimulated emission regime could take efficiency arbitrarily close to the Carnot limit; his team down in Oz are currently up to ~70% - again, for monochromatic (basically laser) light - with increasing applications in ie. wireless power transmission, electrical isolation / firewalling etc., and obvs much greater range (albeit limited to LoS) than classical inductive transmission techniques. A stimulated emission mode / regime is an inherently quantum-classical system, a unique means of corralling quantum systems distinct from Faraday and Maxwell et al; the system's propensity to begin lasing a direct consequence of the quantisation of energy & momentum: in the tensioned 'population inversion' state, ideally at least, a single photon of further input energy will inevitably trigger a cascade of absorption and emission because there's nowhere else for this conserved quantised energy to go, ie. further input energy catalyses a cyclic phase transition between high and low-energy states, because the transitions are quantised, and because a whole bunch of fermions are behaving as a kind of extended quasi-boson, holding the same quantum-energy states at the same time. It's that force-feedback dynamic, like a turbine, generating this low-entropy livewire state of perfect photoelectric synchrony.. coherent emission AND absorption, en masse.. On a bit of a tangent perhaps, but in his later years GC Huth posited that the retinal cells of the fovea may form a kind of phase-conjugate mirror, which may have thought-provoking implications for ie. the nature of eye contact between sentients, optic nerves essentially being extensions of cortex: what if electrons in remote rhodopsin discs are entangled by the same photons? 'A twinkle in the eye'.. 'windows on the soul'.. (woo-wavy hands)
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
Harry wrote: > I had to look up those references. :-) > > Susquehanna Hat Co > https://www.youtube.com/watch?v=THZV5g1CNZM > The Three Stooges - Slowly I Turned > https://www.youtube.com/watch?v=MYP1OBZfFK0 > >> Clearly you have been too enveloped in your flaming youth to appreciate the finer things in life, a hindrance to your cultural and intellectual development ;-)
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
On Thu, Apr 28, 2022 at 2:42 AM William Beaty wrote: > On Wed, 27 Apr 2022, H LV wrote: > > > I have been doing more reading about the history of stimulated > > emission. Einstein formally introduced a quantum version of the concept > in > > 1917. > > "STIMULATED EMISSION!" Oh man don't even get me started. (Too late!) > Saying the words Stimulated Emission, that's like wearing a Susquehanna > hat in an Abbott and Costello bit, and then saying "Niagara Falls" > ...slowly I turned, step by step, INCH BY INCH. > > A very simple classical analog of Stimulated Emission (circuit-based > stimulated emission) ...seems to have been missed by everyone. It's a > part of the "missing physics" of EM wave-absorption by atoms, photon- > destruction, Einstein's fundamental mistakes about photoelectric effect, > as well as being part of the odd "energy-sucking" effects seen with short > resonant antennas. All these topics constitute a single subject, and, > having been missed by Classical physics textbooks, are declared to be > "QM-only phenomena" when they crop up in various places. > > OK, first say we have a classical EM oscillator (a tank circuit hanging in > space,) and it's slowly emitting a small amount of radio waves. Is there > a way to force it to suddenly dump all of its stored energy as a huge > blast of EM radiation? > > Certainly. It's dead-simple stuff. Should be part of every EM textbook. > > But it's not. > > Instead, Stimulated Emission is treated as some rare and unique, QM-only > process, rather than a normal part of basic radio-science. (Similar > treatment is given to the weird behavior of electrically-small resonant > antennas: ignored, except when it crops up as "virtual photon" effects > with atomic resonance, narrow-linewidth photon absorption, > nearfield/evanescent "photon tunneling," etc.) > > I found this paper from 1987 but it is not open access. --- https://opg.optica.org/josab/abstract.cfm?uri=josab-4-1-78 Classical stimulated emission Benjamin Fain and Peter W. Milonni Abstract Stimulated emission is formulated in completely classical terms and is shown to occur in general only in nonlinear systems. Our approach is based on the frequency-dependent susceptibility, which in both the classical and quantum-mechanical descriptions is the main characteristic determining whether there is absorption or stimulated emission. By using Bom’s correspondence rule, we derive an expression for the lowest-order quantum correction to the classical susceptibility. - I want to revisit Rayleigh and Jeans famous classical calculation for the spectral energy distribution from a blackbody that produced the ultraviolet catastrophe. When doing their calculation they required that the electric field on the cavity wall must be zero everywhere for all frequencies. Since the calculation resulted in a physically unrealistic prediction of the spectral energy distribution did it occur to them that the boundary condition was physically unrealistic? How would the calculation change if the electric field were allowed to be frequency dependent? This is a conventional but detailed presentation of Rayleigh and Jeans law for blackbody radiation. https://www.youtube.com/watch?v=rCfPQLVzus4 Harry > Put bluntly, Stimulated Emission works at DC, and obviously applies to > all capacitors. > > If we have a charged capacitor, we can connect it to a resistor, and > remove its energy according to RC time-constant. Or, we can short it out, > and the much shorter RC-constant then depends on the capacitor's internal > impedance, and the micro-ohms of wire resistance (ignoring for the moment > any wave-emission and LC effects.) > > > Or instead, we can force that capacitor to dump out its energy at ANY fast > rate desired, even many orders faster than just shorting it out. > > Simply hook it up to a high-amps constant-current supply. > > But hook it up backwards. > > Before the backwards-connected capacitor can begin to be "charged" by > conneting it to this CC supply, first it has to be discharged to zero > (where the joules in the capacitor are then EMITTED, and they must move > out of the capacitor and into the CC supply.) And clearly we can > discharge this capacitor at ANY rate desired, proportional to the > current-output of the backwards-connected CC supply. > > The discharge-time can easily be orders shorter than any conceivable > natural RC-constant. (The capacitor might possess micro-ohms of internal > resistance, and if it's simply being shorted, have a very short RC time > constant for discharge. But if we apply a huge backwards current, we can > discharge it hundreds of times faster than that, thousands of times, any > speed desired. That's the essence of Stimulated Emission of course: the > max rate of "energy dumping" is determined by the stimulating signal, not > only by the characterists of the energy-storage capacitor (or resonator.) ) > > Pretty cool, eh? > > And,
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
On Thu, Apr 28, 2022 at 2:42 AM William Beaty wrote: > On Wed, 27 Apr 2022, H LV wrote: > > > I have been doing more reading about the history of stimulated > > emission. Einstein formally introduced a quantum version of the concept > in > > 1917. > > "STIMULATED EMISSION!" Oh man don't even get me started. (Too late!) > Saying the words Stimulated Emission, that's like wearing a Susquehanna > hat in an Abbott and Costello bit, and then saying "Niagara Falls" > ...slowly I turned, step by step, INCH BY INCH. > > I had to look up those references. :-) Susquehanna Hat Co https://www.youtube.com/watch?v=THZV5g1CNZM The Three Stooges - Slowly I Turned https://www.youtube.com/watch?v=MYP1OBZfFK0 > >
Re: [Vo]:Stimulated emission and Pre-Quantum Physics
On Wed, 27 Apr 2022, H LV wrote: I have been doing more reading about the history of stimulated emission. Einstein formally introduced a quantum version of the concept in 1917. "STIMULATED EMISSION!" Oh man don't even get me started. (Too late!) Saying the words Stimulated Emission, that's like wearing a Susquehanna hat in an Abbott and Costello bit, and then saying "Niagara Falls" ...slowly I turned, step by step, INCH BY INCH. A very simple classical analog of Stimulated Emission (circuit-based stimulated emission) ...seems to have been missed by everyone. It's a part of the "missing physics" of EM wave-absorption by atoms, photon- destruction, Einstein's fundamental mistakes about photoelectric effect, as well as being part of the odd "energy-sucking" effects seen with short resonant antennas. All these topics constitute a single subject, and, having been missed by Classical physics textbooks, are declared to be "QM-only phenomena" when they crop up in various places. OK, first say we have a classical EM oscillator (a tank circuit hanging in space,) and it's slowly emitting a small amount of radio waves. Is there a way to force it to suddenly dump all of its stored energy as a huge blast of EM radiation? Certainly. It's dead-simple stuff. Should be part of every EM textbook. But it's not. Instead, Stimulated Emission is treated as some rare and unique, QM-only process, rather than a normal part of basic radio-science. (Similar treatment is given to the weird behavior of electrically-small resonant antennas: ignored, except when it crops up as "virtual photon" effects with atomic resonance, narrow-linewidth photon absorption, nearfield/evanescent "photon tunneling," etc.) Put bluntly, Stimulated Emission works at DC, and obviously applies to all capacitors. If we have a charged capacitor, we can connect it to a resistor, and remove its energy according to RC time-constant. Or, we can short it out, and the much shorter RC-constant then depends on the capacitor's internal impedance, and the micro-ohms of wire resistance (ignoring for the moment any wave-emission and LC effects.) Or instead, we can force that capacitor to dump out its energy at ANY fast rate desired, even many orders faster than just shorting it out. Simply hook it up to a high-amps constant-current supply. But hook it up backwards. Before the backwards-connected capacitor can begin to be "charged" by conneting it to this CC supply, first it has to be discharged to zero (where the joules in the capacitor are then EMITTED, and they must move out of the capacitor and into the CC supply.) And clearly we can discharge this capacitor at ANY rate desired, proportional to the current-output of the backwards-connected CC supply. The discharge-time can easily be orders shorter than any conceivable natural RC-constant. (The capacitor might possess micro-ohms of internal resistance, and if it's simply being shorted, have a very short RC time constant for discharge. But if we apply a huge backwards current, we can discharge it hundreds of times faster than that, thousands of times, any speed desired. That's the essence of Stimulated Emission of course: the max rate of "energy dumping" is determined by the stimulating signal, not only by the characterists of the energy-storage capacitor (or resonator.) ) Pretty cool, eh? And, whatever applies to capacitors, also applies to Classical LC tank circuits hovering in the vacuum. An EM-resonator in space, if it contains some stored energy, is slowly leaking away it's EM energy as radio waves (or even optical photons) at the LC resonant freq. We can force it to suddenly dump out all of its energy in any short time desired. Simply blast it with an EM-wave which has 180deg phase relationship to that oscillator. (This is the same as connecting a pre-charged capacitor to a HV power supply, connecting it backwards.) Our tank circuit hovering in space must first discharge all its stored energy, before it can absorb any energy from the EM waves striking it. Blast it with extremely high-amplitude waves, and first it will rapidly "dump" its stored energy ...then quickly fall to zero total stored energy ...then start rapidly absoring energy from the incoming waves.(Viewed from the side, it would suddenly output a huge flash of EM waves, before settling down and becoming a normal absorber.) Everyone knows that we can quickly charge up a capaictor using an HV supply ...and the same applies to LC resonators hooked to HV AC power supplies tuned to resonate. But if the capacitor or the LC resonator already contains some energy, then we can force a sudden "dumping," by connecting it to our power supply backwards. Oddly, I've never encountered ANYONE discussing these concepts. The closest have been the few papers about the enormously wide "effective apertures" seen with short resonant antennas. (And then
[Vo]:Stimulated emission and Pre-Quantum Physics
I have been doing more reading about the history of stimulated emission. Einstein formally introduced a quantum version of the concept in 1917. Therefore you might think that it is only possible in a quantum theoretical context. However, subsequent mathematical work has shown that a form of stimulated emission can also arise in a classical (pre-quantum) setting when a suitable model of the atom is used. Also, it seems to me the concept of stimulated emission represents a revival of Count Rumford's cooling or frigorific radiation but under a different name. The classical physicists who developed radiation theory from the second half the 19th century onwards were ideologically opposed to Rumford's concept of cooling radiation, because at the time there were no unambiguous empirical reasons to accept or reject the concept. However, I am starting to wonder if this ideological opposition to cooling radiation contributed to the "ultraviolet catastrophe" which happened when classical physicists failed to adequately explain the blackbody radiation curve. If that is the case then perhaps Planck's ad hoc introduction of "quanta" could have been avoided if the possibility of stimulated emission or cooling radiation were incorporated into classical accounts of blackbody radiation from the outset. Harry
