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" <hveeder...@gmail.com>
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 ! <mrvibrat...@gmail.com
<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
