|
| 1 | +^{:kindly/hide-code true |
| 2 | + :clay {:title "Emmy, the Algebra System: deBroglie wavelength" |
| 3 | + :quarto {:author :kloimhardt |
| 4 | + :type :draft |
| 5 | + :description "A particle riding its wave whose length depends on the former's momentum" |
| 6 | + :sidebar "emmy-fdg" |
| 7 | + :date "2026-01-27" |
| 8 | + :category :libs |
| 9 | + :tags [:emmy :physics]}}} |
| 10 | + |
| 11 | +(ns mentat-collective.emmy.debroglie |
| 12 | + (:refer-clojure :exclude [+ - * / zero? compare divide numerator denominator |
| 13 | + time infinite? abs ref partial =]) |
| 14 | + (:require [scicloj.kindly.v4.api :as kindly] |
| 15 | + [scicloj.kindly.v4.kind :as kind] |
| 16 | + [mentat-collective.emmy.scheme :refer [define-1 let-scheme lambda]] |
| 17 | + [civitas.repl :as repl])) |
| 18 | + |
| 19 | +^:kindly/hide-code |
| 20 | +(def prod true) #_"used to check Emmy in Scittle kitchen" |
| 21 | + |
| 22 | +^:kindly/hide-code |
| 23 | +(kind/hiccup |
| 24 | + [:div |
| 25 | + [:script {:src "https://cdn.jsdelivr.net/npm/scittle-kitchen@0.7.28-59/dist/scittle.js"}] |
| 26 | + [:script {:src "https://cdn.jsdelivr.net/npm/scittle-kitchen@0.7.28-59/dist/scittle.emmy.js"}] |
| 27 | + [:script {:src "https://cdn.jsdelivr.net/npm/scittle-kitchen@0.7.28-59/dist/scittle.cljs-ajax.js"}] |
| 28 | + [:script {:src "https://cdn.jsdelivr.net/npm/react@18/umd/react.production.min.js", :crossorigin ""}] |
| 29 | + [:script {:src "https://cdn.jsdelivr.net/npm/react-dom@18/umd/react-dom.production.min.js", :crossorigin ""}] |
| 30 | + [:script {:src "https://cdn.jsdelivr.net/npm/scittle-kitchen@0.7.28-59/dist/scittle.reagent.js"}] |
| 31 | + [:script {:type "application/x-scittle" :src "scheme.cljc"}]]) |
| 32 | + |
| 33 | +^:kindly/hide-code |
| 34 | +(defmacro define [& b] |
| 35 | + (list 'do |
| 36 | + (cons 'mentat-collective.emmy.scheme/define b) |
| 37 | + (list 'kind/scittle (list 'quote (cons 'define b))))) |
| 38 | + |
| 39 | +^:kindly/hide-code |
| 40 | +(define emmy-env |
| 41 | + '[emmy.env :refer :all :exclude [Lagrange-equations r->p]]) |
| 42 | + |
| 43 | +^{:kindly/hide-code true :kindly/kind kind/hidden} |
| 44 | +(do |
| 45 | + (require emmy-env)) |
| 46 | + |
| 47 | +^:kindly/hide-code |
| 48 | +(kind/scittle |
| 49 | + '(do |
| 50 | + (require emmy-env))) |
| 51 | + |
| 52 | +^:kindly/hide-code |
| 53 | +(define string-exp (comp str simplify)) |
| 54 | + |
| 55 | +^:kindly/hide-code |
| 56 | +(defn reag-comp [b] |
| 57 | + (let [server-erg (string-exp (eval b))] |
| 58 | + (list 'kind/reagent |
| 59 | + [:div (list 'quote |
| 60 | + (list 'let ['a (list 'string-exp b)] |
| 61 | + [:div |
| 62 | + (when (not prod) |
| 63 | + [:div |
| 64 | + [:tt 'a] |
| 65 | + [:p (list 'str (list '= server-erg 'a))]]) |
| 66 | + [:tt server-erg]]))]))) |
| 67 | + |
| 68 | +^:kindly/hide-code |
| 69 | +(def show-tex-fn (comp kind/tex emmy.expression.render/->TeX)) |
| 70 | + |
| 71 | +^:kindly/hide-code |
| 72 | +(defmacro show-tex [e] |
| 73 | + (if prod |
| 74 | + (list 'show-tex-fn e) |
| 75 | + (reag-comp e))) |
| 76 | + |
| 77 | +^:kindly/hide-code |
| 78 | +(kind/scittle |
| 79 | + '(defn show-tex [e] |
| 80 | + (->infix e))) |
| 81 | + |
| 82 | +^:kindly/hide-code |
| 83 | +(defmacro is-equal [a b] |
| 84 | + (list 'if (list '= (list 'simplify (list '- a b)) 0) |
| 85 | + (list 'show-tex a) |
| 86 | + "not equal")) |
| 87 | + |
| 88 | +^:kindly/hide-code |
| 89 | +(kind/scittle |
| 90 | + '(defn is-equal [a b] |
| 91 | + (if (= (simplify (- a b)) 0) |
| 92 | + (show-tex a) |
| 93 | + "not equal"))) |
| 94 | + |
| 95 | +^:kindly/hide-code |
| 96 | +(defmacro solves [a f] |
| 97 | + (list 'if (list '= (list 'simplify (list f a)) 0) |
| 98 | + (list 'show-tex (list '* (list 'symbol "root:") a)) |
| 99 | + "does not solve")) |
| 100 | + |
| 101 | +^:kindly/hide-code |
| 102 | +(kind/scittle |
| 103 | + '(defn solves [a f] |
| 104 | + (if (= (simplify (f a)) 0) |
| 105 | + (show-tex (* (symbol "root:") a)) |
| 106 | + "does not solve"))) |
| 107 | + |
| 108 | +;; In the following I follow deBroglies arguments. There is also a [version with infix notation](https://kloimhardt.github.io/blog/hamiltonmechanics/2024/09/13/debroglie.html). |
| 109 | + |
| 110 | +;; ### Internal Vibrations |
| 111 | +;;as always with Einstein, we start with E = mc^2 |
| 112 | + |
| 113 | +(define (E0 m) (* m (square 'c))) |
| 114 | + |
| 115 | +(show-tex |
| 116 | + (E0 'm)) |
| 117 | + |
| 118 | +;; deBroglies first hypothesis was to assume that every particle has a hypothetical internal vibration at frequency nu0 which relates to the rest energy in rest frame of particle (only there this energy-frequency relation holds) |
| 119 | + |
| 120 | +(define (nu_naught E0) (/ E0 'h)) |
| 121 | + |
| 122 | +;; particle travels at velocity vp |
| 123 | + |
| 124 | +(define (vp beta) (* beta 'c)) |
| 125 | + |
| 126 | +(define (beta v) (/ v 'c)) |
| 127 | + |
| 128 | +(define (gamma beta) (/ 1 (sqrt (- 1 (square beta))))) |
| 129 | + |
| 130 | +;; time dilation: internal vibration is slower for observer. so the frequency-energy relation does not hold: the frequency indeed decreases instead of increasing with energy. this is the conundrum deBroglie solved. so hang on. |
| 131 | + |
| 132 | +(define (nu_one nu_naught gamma) (/ nu_naught gamma)) |
| 133 | + |
| 134 | +;; sine formula for internal vibration. we do not know what exactly vibrates so we set the amplitude to one |
| 135 | + |
| 136 | +(define ((internal-swing nu_one) t) |
| 137 | + (sin (* 2 'pi nu_one t))) |
| 138 | + |
| 139 | +(show-tex |
| 140 | + ((internal-swing 'nu_one) 't)) |
| 141 | + |
| 142 | +;; calculate the phase of the internal swing at particle point x = v * t |
| 143 | + |
| 144 | +(define ((internal-phase nu_one v) x) |
| 145 | + (asin ((internal-swing nu_one) (/ x v)))) |
| 146 | + |
| 147 | +(is-equal (* 2 'pi 'nu_one (/ 'x 'v)) |
| 148 | + ((internal-phase 'nu_one 'v) 'x)) |
| 149 | + |
| 150 | +;; personal note: to me, this is the sine-part of a standing wave, the standing vibration. |
| 151 | + |
| 152 | +;;### A general Wave |
| 153 | + |
| 154 | +;; now for something completely different: general definition of a wave |
| 155 | + |
| 156 | +(define ((wave omega k) x t) |
| 157 | + (sin (- (* omega t) (* k x)))) |
| 158 | + |
| 159 | +;; with the usual definition of omega |
| 160 | + |
| 161 | +(define (omega nu) (* 2 'pi nu)) |
| 162 | + |
| 163 | +;; and the simplest possible definition for the wave-vector k: a dispersion free wave traveling at phase-velocity V |
| 164 | + |
| 165 | +(define (k omega V) (/ omega V)) |
| 166 | + |
| 167 | +;; calculate the phase of the wave |
| 168 | + |
| 169 | +(define ((wave-phase nu V) x t) |
| 170 | + (asin ((wave (omega nu) (k (omega nu) V)) x t))) |
| 171 | + |
| 172 | +(is-equal (* 2 'pi 'nu (- 't (/ 'x 'V))) |
| 173 | + ((wave-phase 'nu 'V) 'x 't)) |
| 174 | + |
| 175 | +;; ### Phase difference |
| 176 | +;; calculate the phase difference between the vibration and some wave at time t = x / v as a function of the ratio of the frequencies |
| 177 | + |
| 178 | +(define ((phase-difference x v nu V) ratio) |
| 179 | + (- ((internal-phase (* ratio nu) v) x) |
| 180 | + ((wave-phase nu V) x (/ x v)))) |
| 181 | + |
| 182 | +(is-equal (* 2 'pi 'nu (+ (* (- 'ratio 1) (/ 'x 'v)) (/ 'x 'V))) |
| 183 | + ((phase-difference 'x 'v 'nu 'V) 'ratio)) |
| 184 | + |
| 185 | +;; state the general ratio of frequencies that keeps the vibration of the particle in phase with some wave of velocity V in terms of the velocity of the particle |
| 186 | + |
| 187 | +(define (phase-ratio v V) (- 1 (/ v V))) |
| 188 | + |
| 189 | +(solves (phase-ratio 'v 'V) |
| 190 | + (phase-difference 'x 'v 'nu 'V)) |
| 191 | + |
| 192 | +;; the Energy of the particle for the observer |
| 193 | + |
| 194 | +(define (Ev E0 gamma) (* E0 gamma)) |
| 195 | + |
| 196 | +;; we assume the deBroglie wave has the frequency: energy divided by Planck's constant. reminder: this relation holds in every frame of reference, especially for the observer who is not in the rest frame. |
| 197 | + |
| 198 | +(define (nu Ev) (/ Ev 'h)) |
| 199 | + |
| 200 | +;; now that nu is set, calculate the physically viable ratio of the frequencies in terms of beta |
| 201 | + |
| 202 | +(define (physical-ratio beta) |
| 203 | + (/ (nu_one (nu_naught 'E0) (gamma beta)) |
| 204 | + (nu (Ev 'E0 (gamma beta))))) |
| 205 | + |
| 206 | +(is-equal (- 1 (square 'beta)) |
| 207 | + (physical-ratio 'beta)) |
| 208 | + |
| 209 | +;; state, in terms of the particle velocity beta, the value of the physical phase-velocity V that keeps the vibration and the deBroglie wave in phase |
| 210 | + |
| 211 | +(define (phase-velocity beta) (/ 'c beta)) |
| 212 | + |
| 213 | +(solves (phase-velocity 'beta) |
| 214 | + (lambda (V) (- (physical-ratio 'beta) |
| 215 | + (phase-ratio (vp 'beta) V)))) |
| 216 | + |
| 217 | +;; note: the phase-velocity is always greater than the speed of light. It is independent of the position x and the mass of the particle |
| 218 | + |
| 219 | +;; the relativistic momentum is defined as |
| 220 | + |
| 221 | +(define (p m v gamma) |
| 222 | + (* m v gamma)) |
| 223 | + |
| 224 | +;; calculate the deBroglie wavelength (by dividing the phase-velocity by the frequency) and show that it indeed is h divided by the momentum |
| 225 | + |
| 226 | +(define de-broglie-wavelength |
| 227 | + (/ (phase-velocity (beta 'v)) |
| 228 | + (nu (Ev (E0 'm) 'gamma)))) |
| 229 | + |
| 230 | +(is-equal (/ 'h (p 'm 'v 'gamma)) |
| 231 | + de-broglie-wavelength) |
| 232 | + |
| 233 | +(repl/scittle-sidebar) |
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