HAL Id: hal-00942863
https://hal.archives-ouvertes.fr/hal-00942863
Submitted on 6 Feb 2014
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A gradient-like Variational Bayesian approach for
inverse scattering problems
Leila Gharsalli
To cite this version:
Leila Gharsalli. A gradient-like Variational Bayesian approach for inverse scattering problems. 2014.
�hal-00942863�
❆ ❣r❛❞✐❡♥t✲❧✐❦❡ ❱❛r✐❛t✐♦♥❛❧ ❇❛②❡s✐❛♥ ❛♣♣r♦❛❝❤ ❢♦r ✐♥✈❡rs❡ s❝❛tt❡r✐♥❣
♣r♦❜❧❡♠s
▲❡✐❧❛ ●❤❛rs❛❧❧✐
▲❛❜♦r❛t♦✐r❡ ❞❡s ❙✐❣♥❛✉① ❡t ❙②stè♠❡s ✭▲✷❙✮
❯▼❘✽✺✵✻✿ ❈◆❘❙✲❙❯P❊▲❊❈✲❯♥✐✈ P❛r✐s✲❙✉❞
✸ r✉❡ ❏♦❧✐♦t✲❈✉r✐❡✱ ✾✶✶✾✵ ●✐❢✲s✉r✲❨✈❡tt❡✱ ❋r❛♥❝❡
❊✲♠❛✐❧✿ ❧❡✐❧❛✳❣❤❛rs❛❧❧✐❅❧ss✳s✉♣❡❧❡❝✳❢r
❆❜str❛❝t
■♥ t❤✐s ❞♦❝✉♠❡♥t✱ ✇❡ ♣r❡s❡♥t ❝♦♠♣✉t❛t✐♦♥s ♦❢ ✉♣❞❛t✐♥❣ s❤❛♣✐♥❣ ♣❛r❛♠❡t❡rs ❢♦r ❛ ♥❡✇ ♠❡t❤♦❞ ❜❛s❡❞ ♦♥ t❤❡
✈❛r✐❛t✐♦♥❛❧ ❇❛②❡s✐❛♥ ❛♣♣r♦❛❝❤ ✭❱❇❆✮ ❛❧❧♦✇✐♥❣ t♦ s♦❧✈❡ ❛ ♥♦♥❧✐♥❡❛r ✐♥✈❡rs❡ s❝❛tt❡r✐♥❣ ♣r♦❜❧❡♠✳ ❚❤❡ ♦❜❥❡❝t✐✈❡ ✐s t♦ ❞❡t❡❝t ❛♥ ✉♥❦♥♦✇♥ ♦❜❥❡❝t ❢r♦♠ ♠❡❛s✉r❡♠❡♥ts ♦❢ t❤❡ s❝❛tt❡r❡❞ ✜❡❧❞ ❛t ❞✐✛❡r❡♥t ❢r❡q✉❡♥❝✐❡s ❛♥❞ ❢♦r s❡✈❡r❛❧
✐❧❧✉♠✐♥❛t✐♦♥s✳ ❚❤✐s ✐♥✈❡rs❡ ♣r♦❜❧❡♠ ✐s ❦♥♦✇♥ t♦ ❜❡ ♥♦♥✲❧✐♥❡❛r ❛♥❞ ✐❧❧✲♣♦s❡❞✳ ❙♦ ✐t ♥❡❡❞s t♦ ❜❡ r❡❣✉❧❛r✐③❡❞ ❜②
✐♥tr♦❞✉❝✐♥❣ ❛ ♣r✐♦r✐ ✐♥❢♦r♠❛t✐♦♥✳ ❚❤✐s ✐s t❛❝❦❧❡❞ ✐♥ ❛ ❇❛②❡s✐❛♥ ❢r❛♠❡✇♦r❦ ✇❤❡r❡ t❤❡ ♣❛rt✐❝✉❧❛r ♣r✐♦r ✐♥❢♦r♠❛t✐♦♥
✇❡ ❛❝❝♦✉♥t ❢♦r ✐s t❤❛t t❤❡ ♦❜❥❡❝t ✐s ❝♦♠♣♦s❡❞ ♦❢ ❛ ✜♥✐t❡ ❦♥♦✇♥ ♥✉♠❜❡r ♦❢ ❞✐✛❡r❡♥t ♠❛t❡r✐❛❧s ❞✐str✐❜✉t❡❞ ✐♥ ❝♦♠♣❛❝t r❡❣✐♦♥s✳ ❚❤❡♥ ✇❡ ♣r♦♣♦s❡ t❤❡ ❛♣♣r♦①✐♠❛t❡ t❤❡ tr✉❡ ❥♦✐♥t ♣♦st❡r✐♦r ❜② ❛ s❡♣❛r❛❜❧❡ ❧❛✇ ❜② ♠❡❛♥ ♦❢ ❛ ❣r❛❞✐❡♥t✲❧✐❦❡
❱❛r✐❛t✐♦♥❛❧ ❇❛②❡s✐❛♥ t❡❝❤♥✐q✉❡✳ ❚❤✐s ❧❛tt❡r ✐s ❛♣♣❧✐❡❞ t♦ ❝♦♠♣✉t❡ t❤❡ ♣♦st❡r✐♦r ❡st✐♠❛t♦rs ❜② ❛❧❧♦✇✐♥❣ ❛ ❥♦✐♥t
✉♣❞❛t❡ ♦❢ t❤❡ s❤❛♣❡ ♣❛r❛♠❡t❡rs ♦❢ t❤❡ ❛♣♣r♦①✐♠❛t✐♥❣ ♠❛r❣✐♥❛❧s ❛♥❞ r❡❝♦♥str✉❝t t❤❡ s♦✉❣❤t ♦❜❥❡❝t✳ ❚❤❡ ♠❛✐♥ ✇♦r❦
✐s ❣✐✈❡♥ ✐♥ ❬✹❪✱ ✇❤✐❧❡ t❡❝❤♥✐❝❛❧ ❞❡t❛✐❧s ♦❢ t❤❡ ✈❛r✐❛t✐♦♥❛❧ ❝❛❧❝✉❧❛t✐♦♥s ❛r❡ ♣r❡s❡♥t❡❞ ✐♥ t❤❡ ❝✉rr❡♥t ♣❛♣❡r✳
✶ ■♥tr♦❞✉❝t✐♦♥
❚❤❡ ❣r❛❞✐❡♥t✲❧✐❦❡ ❱❛r✐❛t✐♦♥❛❧ ❇❛②❡s✐❛♥ ❛♣♣r♦❛❝❤ ❢r♦♠ ♥♦✇ ♦♥ ❞❡♥♦t❡❞ ❛s ●❱❇❆ ✐s ❞❡r✐✈❡❞ ❢r♦♠ t❤❡ ❝❧❛ss✐❝❛❧ ✈❛r✐❛t✐♦♥❛❧
❇❛②❡s✐❛♥ ❛♣♣r♦❛❝❤ ✭❱❇❆✱ ❬✶❪✮ t❤❛t ❛✐♠s ❛t ❛♣♣r♦①✐♠❛t✐♥❣ ❛ ❥♦✐♥t ♣♦st❡r✐♦r ❞✐str✐❜✉t✐♦♥ p(x|y) ❜② ❛ s❡♣❛r❛❜❧❡ ❧❛✇
q(x) =Q
iqi(xi)✇❤✐❝❤ ✐s ❛s ❝❧♦s❡ t♦ t❤❡ ♣♦st❡r✐♦r ❞✐str✐❜✉t✐♦♥ ❛s ♣♦ss✐❜❧❡ ✐♥ t❡r♠s ♦❢ t❤❡ ❑✉❧❧❜❛❝❦✲▲❡✐❜❧❡r ❞✐✈❡r❣❡♥❝❡✳
■t ❝❛♥ ❜❡ ♥♦t❡❞ t❤❛t ♠✐♥✐♠✐③✐♥❣ t❤❡ ❑▲ ❞✐✈❡r❣❡♥❝❡ ✐s ❡q✉✐✈❛❧❡♥t t♦ ♠❛①✐♠✐③✐♥❣ t❤❡ ❢r❡❡ ♥❡❣❛t✐✈❡ ❡♥❡r❣② ❞❡r✐✈❡❞
❢r♦♠ st❛t✐st✐❝❛❧ ♣❤②s✐❝s F(q) =R
q(x) ln (p(y, x)/q(x))❞x✳ ❚❤❡ s♦❧✉t✐♦♥ ♦❢ t❤✐s ♣r♦❜❧❡♠ ❝❛♥ ❜❡ ♦❜t❛✐♥❡❞ ❜② ❛❧t❡r♥❛t❡
♦♣t✐♠✐③❛t✐♦♥ ✇✐t❤ r❡s♣❡❝t t♦ ❡❛❝❤ qi(xi)❛♥❞ ✐s ❣✐✈❡♥ ❜②✿
qi(xi) ∝ expD
ln(p(x, y))E
Q
j6=iqj(xj)
. ✭✶✮
❚❤❡ ❝♦♠♣✉t❛t✐♦♥ ♦❢ qi r❡q✉✐r❡s t❤❡ ❦♥♦✇❧❡❞❣❡ ♦❢ ❛❧❧ qj✱ j 6= i✳ ❍♦✇❡✈❡r✱ r❡❝❡♥t❧②✱ ♦t❤❡r ✇❛②s t❤❛♥ t❤✐s ❝❧❛ss✐❝❛❧
❛❧t❡r♥❛t❡ ♦♣t✐♠✐③❛t✐♦♥ ❤❛✈❡ ❜❡❡♥ ✐♥✈❡st✐❣❛t❡❞ ❬✺❪✳ ■♥ ❢❛❝t✱ t❤❡ ♦♣t✐♠✐③❛t✐♦♥ ✐♥✈♦❧✈❡❞ ✐♥ ❱❇❆ ✐s ❛♥ ✐♥✜♥✐t❡ ❞✐♠❡♥s✐♦♥❛❧
❝♦♥❝❛✈❡ ♣r♦❜❧❡♠✳ ❍❡♥❝❡✱ ❛♣♣r♦①✐♠❛t✐♥❣ ❞❡♥s✐t✐❡s qi(xi)❝❛♥ ❜❡ ♦❜t❛✐♥❡❞ ❜② ❛❞❛♣t✐♥❣ ❛ ❝❧❛ss✐❝❛❧ ♦♣t✐♠✐③❛t✐♦♥ ❛❧❣♦r✐t❤♠✱
s✉❝❤ ❛s ❛ ❣r❛❞✐❡♥t ♠❡t❤♦❞✱ t♦ ❱❇❆✳ ❯s✐♥❣ t❤❡ ♥♦t✐♦♥ ♦❢ ♦♣t✐♠❛❧ st❡♣✱ t❤❡ ❛♣♣r♦①✐♠❛t✐♥❣ ♠❛r❣✐♥❛❧s ❤❛✈❡ ❛♥ ✐t❡r❛t✐✈❡
❢✉♥❝t✐♦♥❛❧ ❢♦r♠✳ ❆t ✐t❡r❛t✐♦♥ n✱ t❤❡② r❡❛❞✿
e
q(n)i (xi) ∝ eqi(n−1)(xi)(1−α)
× exp
αD
ln(p(x, y))E
Q
i6=j eq(n−1) j (xj )
✭✷✮
✇❤❡r❡ α ≥ 0 ✐s ❛ ❞❡s❝❡♥t st❡♣ t❤❛t ♠✐♥✐♠✐③❡s t❤❡ ❢r❡❡ ♥❡❣❛t✐✈❡ ❡♥❡r❣② ❛t ❡❛❝❤ ✐t❡r❛t✐♦♥✳
✶
✷ ❇❛②❡s✐❛♥ ❝♦♠♣✉t❛t✐♦♥s
▲❡t ✉s r❡❝❛❧❧ ♥♦✇ ❛❧❧ t❤❡ ❡①♣r❡ss✐♦♥s ♦❢ ♣r✐♦rs ❛♥❞ ❧✐❦❡❧✐❤♦♦❞s ✉s❡❞ ✐♥ t❤❡ ❇❛②❡s✐❛♥ ❢r❛♠❡✇♦r❦ ✐♥ t❤❡ ❝❛s❡ ♦❢ ❛ ♥♦♥✲❧✐♥❡❛r
✐♥✈❡rs❡ s❝❛tt❡r✐♥❣ ♣r♦❜❧❡♠ ❬✸❪✳ ❚❤❡♥ ✇❡ ❣✐✈❡ t❤❡ ❢♦r♠ ♦❢ s❡♣❛r❛t✐♦♥ ❛♥❞ ❡①♣r❡ss✐♦♥s ♦❢ ❛♣♣r♦①✐♠❛t✐♥❣ ❧❛✇s ❢♦r ❞✐✛❡r❡♥t
♣❛r❛♠❡t❡rs ✭✇❡ ❝❛♥ ❝❤❡❝❦ s❡✈❡r❛❧ r❡❢❡r❡♥❝❡s ❬✷✱ ✸✱ ✻❪ ❢♦r t❤❡ ❢♦r✇❛r❞ ♠♦❞❡❧❧✐♥❣ ♦❢ t❤❡ ♣r♦❜❧❡♠ ❛♥❞ ✐ts ❢♦r♠✉❧❛t✐♦♥✮✳
❲❡ ❤❛✈❡✿
q(y|w, vǫ) = N (Gow, vǫ■), q(w|χ, vξ) = N (mw, Vw), q(χ|z, m, v) = N (mχ, Vχ), q(z) = exp
( λX
r X
r′
δ(z(r) − z(r′)) )
, p(mk) = N (mk|µ0, τ0), p(vk) = IG(vk|η0, φ0),
p(vǫ) = IG(vǫ|ηǫ, φǫ), p(vξ) = IG(vξ|ηξ, φξ),
✭✸✮
❲❡ ❞❡♥♦t❡ ψ = {m, v, vǫ, vξ} t❤❡ s❡t ♦❢ t❤❡ ❤②♣❡r✲♣❛r❛♠❡t❡rs ♦❢ t❤❡ ♠♦❞❡❧✳ ❈♦♥s❡q✉❡♥t❧②✱ t❤❡ ❥♦✐♥t ❞✐str✐❜✉t✐♦♥
♦❢ t❤❡ ✉♥❦♥♦✇♥s r❡❛❞s✿
p (χ, w, z, ψ|y) ∝ p (y|w, vǫ) p (w|χ, vξ) p (χ|z, m, v) p (z|λ) p (m|µ0, τ0)
× p (v|η0, φ0) p (vǫ|ηǫ, φǫ) p (vξ|ηξ, φξ)
∝ ηK(φ0 0−1)η(φǫ ǫ−1)ηK(φξ ξ−1)
A exp
−||y − Gow||22 2vǫ
× exp
−||w − XEinc− XGcw||22 2vξ
× exp
−(χ − mχ)TVχ−1(χ − mχ) 2
× exp
λX i
X j
δ(z(i) − z(j)) − T (λ)
v−φǫ ǫ−1
× exp
−ηǫ
vǫ
vǫ−φξ−1exp
−ηξ
vξ
YK
k=1
vk−φ0−1
× exp
−η0
vk
exp
−|mk− µ0|2 2τ0
∝ exp {L}, ✭✹✮
✇❤❡r❡ A = (2π)M+N (NP +1)+K
2 (vǫ)M2 (vξ)N×NP2 |Vχ|(−1/2)(τ0)(K/2)Γ(φ0)KΓ(φǫ)Γ(φξ)✇❤❡r❡ M ✐s t❤❡ ♥✉♠❜❡r ♦❢ s♦✉r❝❡s✱
N t❤❡ ♥✉♠❜❡r ♦❢ t❤❡ ❡❧❡♠❡♥t❛r② sq✉❛r❡ ♣✐①❡❧s✱ NP t❤❡ ♥✉♠❜❡r ♦❢ ♣♦❧❛r✐③❛t✐♦♥ ✭NP = 1❉✱ 2❉ ♦r 3❉✮ ❛♥❞ L r❡❛❞s✿
L = −
M 2
log(vǫ) −
N NP
2
log(vξ)
− 1
2vǫ
||y − Gow||22− 1 2vξ
||w − XEinc− XGcw||22
− P
kNklog (vk)
2 −X
k
X r
|χ(r) − mk(r)|2 2vk
+ λX
r X
r′
δ(z(r) − z(r′)) − P
k|mk− µ0|2 2τ0
− X
k
η0
vk
+ (φ0+ 1) log(vk)
−ηǫ
vǫ
− (φǫ+ 1) log (vǫ)
− ηξ
vξ
− (φξ+ 1) log (vξ). ✭✺✮
✷
❲❡ ♠❛② ♥♦t❡ t❤❛t ❛♣♣❧②✐♥❣ t❤❡ ❥♦✐♥t ♠❛①✐♠✉♠ ❛ ♣♦st❡r✐♦r✐ ✭❏▼❆P✮ ♦r t❤❡ ♣♦st❡r✐♦r ♠❡❛♥ ✭P▼✮ t♦ ❝♦♠♣✉t❡ t❤❡
❥♦✐♥t ♣♦st❡r✐♦r ❞✐str✐❜✉t✐♦♥ ✭❡q✉❛t✐♦♥ ✭✹✮✮ ②✐❡❧❞s ✐♥tr❛❝t❛❜❧❡ ❢♦r♠ ❛♥❞ ❛♥ ❛♣♣r♦①✐♠❛t✐♦♥ ✐s ♥❡❡❞❡❞ t♦ ♦❜t❛✐♥ ❛ ♣r❛❝t✐❝❛❧
s♦❧✉t✐♦♥✳ ❚❤✐s ✐s ❞♦♥❡ ❜② ♠❡❛♥s ♦❢ t❤❡ ●❱❇❆✳ ❋✐rst✱ ❛ str♦♥❣ s❡♣❛r❛t✐♦♥ ✐s ❝❤♦s❡♥✿
q(x) = q(vǫ)q(vξ) ×Y
i
q(χi)q(wi)q(zi)Y
k
q(mk)q(vk). ✭✻✮
❚❤❡♥✱ ✉s✐♥❣ ❡q✉❛t✐♦♥ ✭✷✮✱ t❤❡ ❛♣♣r♦①✐♠❛t✐♥❣ ♠❛r❣✐♥❛❧ ❢♦r ❡❛❝❤ ✉♥❦♥♦✇♥ ✈❛r✐❛❜❧❡ ❝❛♥ ❜❡ ❝♦♠♣✉t❡❞ ❜② ♠❡❛♥s ♦❢
❢✉♥❝t✐♦♥❛❧ ♦♣t✐♠✐③❛t✐♦♥✳ ❯♣❞❛t✐♥❣ t❤❡ ❛♣♣r♦①✐♠❛t❡ ♣♦st❡r✐♦r r❡q✉✐r❡s 7 ❞✐✛❡r❡♥t ❣r❛❞✐❡♥t st❡♣s t❤❛t ✇❡ ❞❡♥♦t❡ ❜② αw✱ αχ✱ αz✱ αvǫ✱αvξ✱ αvk ❛♥❞ αmk✳
✷✳✶ ❯♣❞❛t❡ s❤❛♣✐♥❣ ♣❛r❛♠❡t❡rs
❆t t❤✐s ♣♦✐♥t✱ ✐t ❝❛♥ ❜❡ ♠❡♥t✐♦♥❡❞ t❤❛t t❛❦✐♥❣ t❤❡ ❧✐❦❡❧✐❤♦♦❞ ✐♥ t❤❡ ❡①♣♦♥❡♥t✐❛❧ ❢❛♠✐❧② ❛♥❞ ✉s✐♥❣ ❝♦♥❥✉❣❛t❡ ♣r✐♦rs ✇✐❧❧
r❡s✉❧t ✐♥ ❥♦✐♥t ♣♦st❡r✐♦rs ❛♥❞ ♠❛r❣✐♥❛❧s r❛♥❣✐♥❣ ✐♥ t❤❡ ❡①♣♦♥❡♥t✐❛❧ ❢❛♠✐❧②✳ ❖♣t✐♠✐③❛t✐♦♥ ✇✐t❤ r❡s♣❡❝t t♦ qi(xi)t❤❡♥
r❡s✉❧ts ✐♥ ♦♣t✐♠✐③✐♥❣ t❤❡ ♣❛r❛♠❡t❡rs ♦❢ t❤❡s❡ ❧❛✇s✳ ■♥ t❤❡ ❢♦❧❧♦✇✐♥❣ ✇❡ s✉♠♠❛r✐③❡ t❤❡ r❡s✉❧ts ❢♦r t❤❡ ●❛✉ss✐❛♥ ✲ ✐♥✈❡rs❡
❣❛♠♠❛ ❝❛s❡✿
q(w) = N (mfw, eVw), q(χ) = N (mfχ, eVχ), q(mk) = N (eµk, eτk), q(vk) = IG(eηk, eφk),
q(vǫ) = IG(eηǫ, eφǫ), q(vξ) = IG(eηξ, eφξ),
q(z) = eζk∝ exp
λX r∈D
X r′∈V (r)
ζ(re ′)
, ✭✼✮
✇❤❡r❡ t✐❧❞❡❞ ♣❛r❛♠❡t❡rs ❛r❡ ❣✐✈❡♥ ✐♥ t❤❡ ❢♦❧❧♦✇✐♥❣✳ ❚❤❡ ❦❡② ✉s❡❞ t♦ ♦❜t❛✐♥ t❤❡s❡ ❢♦r♠s ✐s ❡q✉❛t✐♦♥ ✭✷✮✳
✷✳✶✳✶ ❈♦♥tr❛st s♦✉r❝❡ w
log (eqn(w(i))) ∝ (1 − αw) log (eq(w(i))) + αw hlog (p (χ, w, z, ψ, y))iq(/w(˜ i))
∝ (1 − αw)h e
vw(i)w(i)2− 2fmw(i)w(i)i
+ αw hlog (p(y|w, vǫ)) + log (p(w|χ, vξ))iq(/w(˜ i))
∝ (1 − αw)h e
vw(i)w(i)2− 2fmw(i)w(i)i
− αw
2
||y − Gow||22 vǫ
+ ||w − XEinc− XGcw||22 vξ
˜
q(/w(i)) ✭✽✮
✇❤❡r❡ q(/w(i)) =Q
j6=iq(w(j))q(χ)q(z)q(ψ)✳ ❖r ||y − Gow||22
˜
q(/w(i)) ∝ X l
|Go(l, i)|2|w(i)|2
+ 2 ℜe
X k
Go∗(k, i)
y(k) −X j6=i
Go(k, j) emw(j)
w∗(i)
,
❛♥❞
✸
||w − XEinc− XGcw||22
˜
q(/w(i)) ∝ |w(i)|2− Gc∗(i, i) ¯χ∗(i) |w(i)|2− Gc(i, i) ¯χ(i) |w(i)|2
+ X
j
|Gc(j, i)| |χ(i)|2|w(i)|2− 2 ℜe Einc(i) ¯χ(i)w∗(i)
+ 2 ℜe
X j
|Gc∗(j, i)| |χ(j)|2|w∗(j)|2
− 2 ℜe
X
j6=i
¯
χ(i) Gc(i, j) ¯w(j) w∗(i)
− 2 ℜe
X
j6=i
¯
χ∗(j) Gc∗(j, i) ¯w(j) w∗(i)
+ 2 ℜe
X j
Gc∗(j, i)|χ(j)|2 X k6=i
Gc(j, k) ¯w(k) w∗(i)
+ cte.
✇❤❡r❡∗ ❞❡♥♦t❡s t❤❡ ❝♦♥❥✉❣❛t❡ ❝♦♠♣❧❡①✳
❍❡♥❝❡✱ ❜② ❝♦♠❜✐♥✐♥❣ ❛❧❧ t❤❡ t❡r♠s✱ t❤❡ ❛♣♣r♦①✐♠❛t✐♥❣ ❧❛✇✱ ❛t t❤❡ ✐t❡r❛t✐♦♥ n✱ ❜❡❝♦♠❡s qn(w) = N (fmnw, eVnw)
✇❤❡r❡✿
Vewn(i) =
"
(1 − αw) eVw(i) + αw vǫ−1
X j
|Go(j, i)|2
+ vξ−1
1 − 2 ℜe Gc(i, i) emχ(i)
+X
j
|Gc(j, i)|2 | emχ(i)|2+ eVχ(i)!#−1 ,
e mnw(i)
Vewn(i) = (1 − αw) emw(i) + αw
"
vǫ−1
X k
Go∗(k, i)
y(k) −X
j6=i
Go(k, j) emw(j)
+ v−1ξ Einc(i) emχ(i) −X j
Gc∗(j, i)
| emχ(j)|2+ eVχ(j)
Einc(j)
+ X
j6=i e
mχ(i)Gc(i, j) emw(j) +X j6=i
e
m∗χ(i)Gc∗(j, i) emw(j)
− X
j
Gc∗(j, i)
| emχ(i)|2+ eVχ(i) X k6=j
Gc(j, k)w(k)
!#
,
❇② ❛❞❞✐♥❣ t❤❡ ♠✐ss✐♥❣ emw t♦ t❤❡ r✐❣❤t✲❤❛♥❞ s✐❞❡ ♦❢ t❤❡ ♣r❡✈✐♦✉s ❡q✉❛t✐♦♥ ❛♥❞ ♣✉tt✐♥❣ ✐t ✐♥ ❛ ✈❡❝t♦r✐❛❧ ❢♦r♠✱ ✇❡
♦❜t❛✐♥ t❤❡ ✜♥❛❧ ❢♦r♠✿
Venw=h
(1 − αw) eV−1w + αw ❉✐❛❣
v−1ǫ Γo+ v−1ξ Γxci−1
f
mnw=fmw+ αwVenw
""
v−1ǫ GoH(y − Gofmw) + vξ−1
f
mχEinc− GcH f m2χ+ eVχ
Einc
− fmw+mfχGcmfw+ GcHfm∗χmfw− GcH f m2χ+ eVχ
Gcfmw
##
✭✾✮
✇❤❡r❡ ♦✈❡r❧✐♥❡ ❞❡♥♦t❡s t❤❡ ❡①♣❡❝t❛t✐♦♥ ♦❢ t❤❡ ✈❛r✐❛❜❧❡ ✇✐t❤ r❡s♣❡❝t t♦ q ✭✐✳❡✳ u = ❊(u)q✮✱ s✉♣❡rs❝r✐♣tH ✐♥❞✐❝❛t❡s t❤❡
❝♦♥❥✉❣❛t❡ tr❛♥s♣♦s❡ ❛♥❞ Γo❛♥❞ Γxc ❛r❡ ❣✐✈❡♥ ❛s✿
✹
Γo(i) = X j
|Go(j, i)|2,
Γxc(i) = 1 − 2ℜe(Gc(i, i) emχ(i)) + ( em2χ(i) + eVχ(i))X
j
|Gc(j, i)|2
✷✳✶✳✷ ❈♦♥tr❛st χ
log (eqn(χ(i))) ∝ (1 − α) log (eq(χ(i))) + αχ hlog (p (χ, w, z, ψ, y))iq(/χ(˜ i))
∝ (1 − αχ)h e
vχ(i)χ(i)2− 2fmχ(i)χ(i)i
+ αχ hlog (p(w|χ, vǫ)) + log (p(χ|z, v, m))iq(/χ(˜ i))
∝ (1 − αχ)h e
vχ(i)χ(i)2− 2fmχ(i)χ(i)i + αχ
||w − XE||22 vξ
+ (χ − mχ)TV−1χ (χ − mχ)
˜ q(/χ(i))
, ✭✶✵✮
✇❤❡r❡ q(/χ(i)) =Q
j6=iq(χ(j))q(w)q(z)q(ψ)✱ ♦r ||w − XE||22
˜
q(/χ(i)) ∝ −2ℜe
w∗(i)E(i)χ(i)
+ E2(i)|χ(i)|2
+
*
||w||22− 2ℜe
X
j6=i
w∗(j)E(j)χ(j)
+X j6=i
|E(j)χ(j)|2 +
˜ q(/χ(i))
,
❛♥❞
D
(χ − mχ)TV−1χ (χ − mχ)E
˜
q(/χ(i)) ∝ X j
||χ(j) − mk||22 vk
˜ q(/χ(i))
∝ vk−1 |χ(i)|2− 2ℜe (fmkχ∗(i)) ,
❇② ✐❞❡♥t✐✜❝❛t✐♦♥✱ ✇❡ ✜♥❞
Veχn(i) ∝ h
(1 − αχ) eVχ(i)−1+ αχ
vξ−1E2(i) + evχ−1(i)i−1
,
❛♥❞
e mnχ(i)
Veχn(i) ∝ (1 − αχ) emχ(i) + αχ
"
e mχ(i)
Veχ(i) + vξ−1w(i)E∗(i)
# ,
✇❤❡r❡ wE∗ ✐s t❤❡ ♠❡❛♥ ♦❢ t❤❡ ✈❡❝t♦r wE∗s✉❝❤ t❤❛t✿
wE∗(i) = X
NfNvN
Einc∗(i) emw(i) + emw(i)X
jb
Gc∗(i, i′) em∗w(i′)
+ Gc∗(i, i) eVw(i),
❛♥❞ E2✐s ❛ ❞✐❛❣♦♥❛❧ ♠❛tr✐❝❡ ✇❤♦s❡ ❡❧❡♠❡♥ts ❛r❡ ✇r✐tt❡♥ s✉❝❤ t❤❛t✿
E2(i) = X
NfNvNP
|Einc(i)|2+ 2ℜe Einc∗(i)Gcmew(i)
+ |X i′
Gc(i, i′) emw(i)|2+X i′
|Gc(i, i′)|2Vew(i),
✺
❚❤❡♥ t❤❡ ✈❡❝t♦r✐❛❧ ❢♦r♠ ✐s ❣✐✈❡♥ ❜②✿
Venχ=h
(1 − αχ) eV−1χ + αχ
❉✐❛❣
vξ−1E2+ V−1χ i−1
f
mnχ = αχ VenχhP
kv−1k eζk◦ fmk+ v−1ξ w◦ E∗i ✭✶✶✮
✇❤❡r❡ Vχ−1(i, i) =P
keζk(i)v−1k .
✷✳✶✳✸ ❚❤❡ ❤✐❞❞❡♥ ✜❡❧❞ z
log (eqn(z(i))) ∝ (1 − αz) log (eq(z(i))) + α hlog (p (χ, w, z, ψ, y))iq(/z(˜ i))
∝ (1 − αz) log (eq(z(i))) + αz
*
−1
2log(vk) +||χ(i) − mχ(i)||22 2vk
− λ X
l∈V(i)
δ (z(l) − k) +
˜ q(/z(i))
∝ (1 − α) log ζek(i)
−αz
2
"
log(vk) + v−1k h|χ(i) − mχ(i)|iq(/z(˜ i))
− 2λ X
j∈V(i)
ζek(j)
#
∝ (1 − αz) log ζek(i)
−αz
2
"
Ψ(˜ηk) − log ˜φk+ vk−1h
| emχ(i)|2
+ me†k− 2ℜe em†χme∗χ(i) i
+ λ X
j∈V(i)
ζek(j)
# ,
✇❤❡r❡ q(/z(i)) =Q
j6=iq(z(j))q(χ)q(w)q(ψ)❛♥❞ em†2χ = em2k+ eτk✳
❇② ✐❞❡♥t✐✜❝❛t✐♦♥✱ ✐t ❜❡❝♦♠❡s✿
ζekn = ζek(1−αz)exp (
−αz
2 Ψ(eηk) + log( eφk) + vk−1
( emχ(i) − eµk)2+ eτk
+ Veχ(r)
− λ X
i′∈V(r) eζk(i′)
!)
, ✭✶✷✮
✇❤❡r❡ Ψ(x) =∂x∂ log Γ(x)t❤❡ ❞✐❣❛♠♠❛ ❢✉♥❝t✐♦♥ ✇✐t❤ Γ(x) ✐s t❤❡ ❣❛♠♠❛ ❢✉♥❝t✐♦♥✳
✷✳✶✳✹ ❚❤❡ ♦❜s❡r✈❛t✐♦♥ ✈❛r✐❛♥❝❡ vǫ
log (eqn(vǫ)) ∝ (1 − αvǫ) log (eq(vǫ)) + αvǫ hlog (p (χ, w, z, ψ, y))iq(/v˜ ǫ)
∝ (1 − αvǫ)
−vǫ
˜
ηǫ + ( ˜φǫlog(vǫ))
+ αvǫ hp(y|w, vǫ)p(vǫ|ηǫ, φǫ)iq(/v˜ ǫ), ✭✶✸✮
✇❤❡r❡ q(/vǫ)) = q(χ)q(w))q(z)Q
l6=vǫq(ψl)✱ ✇✐t❤✿
hp(y|w, vǫ)p(vǫ|ηǫ, φǫ)iq(/v˜ ǫ) ∝
−M
2 log(vǫ) −||y − Gow||22 2vǫ
−ηǫ
vǫ
− (φǫ− 1) log(vǫ)
˜ q(/vǫ)
∝ −(1 + φǫ+M
2 ) log(vǫ) − v−1ǫ
ηǫ+||y − Gow||22 2
˜ q(/vǫ)
,
✇❤❡r❡
✻
||y − Gow||22
˜
q(/vǫ) ∝ X i
|y(i)|2+X j
X k
Go(i, k) emw(j) em∗w(k) +X j
|Go(i, j)|evw(j)
− 2ℜe y∗X
j
Go(i, j) em∗w(j)! ,
❇② ✐❞❡♥t✐✜❝❛t✐♦♥✱ ✇❡ ♦❜t❛✐♥✿
φenǫ = (1 − αvǫ) eφǫ+ αvǫ φǫ+M2 e
ηnǫ =1−αeηvǫ
ǫ + αvǫ ηǫ+12
||y||22+ ||Gofmw||22− 2ℜe(yHGofmw) + ||Go2evw||1
!
✭✶✹✮
✷✳✶✳✺ ❈♦✉♣❧✐♥❣ ♥♦✐s❡ vξ
log (eqn(vξ)) ∝ 1 − αvξ
log (eq(vξ)) + αξ hlog (p (χ, w, z, ψ, y))iq(/v˜ ξ)
∝ 1 − αvξ
−vξ
˜ ηξ
+ ( ˜φξ− log(vξ))
+ αvξ hp(w|χ, vξ)p(vξ|ηξ, φξ)iq(/v˜ ξ), ✭✶✺✮
✇❤❡r❡ q(/vξ)) = q(χ)q(w))q(z)Q
l6=vξq(ψl)✇✐t❤
hp(w|χ, vξ)p(vξ|ηξ, φξ)iq(/v˜
ξ) ∝
log vξ−NP N2 −||w − XE||22 2vξ
−ηξ
vξ
− (φξ+ 1) log(vξ)
˜ q(/vξ)
∝
ηξ+NPN 2
log (vξ) − v−1ξ
ηξ+||w − XE||22 2
˜ q(/vξ)
,
❛♥❞
||w − XE||22
˜
q(/vξ) = X i
| emw(i)|2+ evw(i) +
| emχ(i)|2+ evw(i) E2(i)
− 2ℜe e
mχ(i)w∗(i)E(i)! ,
❇② ✐❞❡♥t✐✜❝❛t✐♦♥ ✇❡ ✜♥❞✿
φenξ = 1 − αvξ eφξ+ αvξ φξ+NP2N
αvξ dχ+ 1 − αvξ f mχ e
ηξn = 1−αeηvξ
ξ + αvξ ηξ+12
||fmw||22+ || eVw||22+ || f m2χ+ eVχ
E2||1
− 2ℜe f
mHχw◦ E∗ ! ✭✶✻✮
✇❤❡r❡ dχ=P
kvk−1eζk◦ fm†χ+ v−1ξ w◦ E∗✳
✷✳✶✳✻ ❱❛r✐❛♥❝❡ ♦❢ t❤❡ ❝❧❛ss❡s vk
∀κ ∈ {1, ..., K}✇❡ ❤❛✈❡✿
✼
log (eqn(vk)) ∝ (1 − α) log (eq(vk)) + αvk hlog (p (χ, w, z, ψ, y))iq(/v˜ k)
∝ (1 − αvk)
−vk
˜ ηk
+ ( ˜φk− 1) log(vk)
+ αvk
*
−1 2
X i
δ(z(i) = κ)
×
log(vk) +|χ(i) − mk|2 vk
+η0
vk
+ (φ0+ 1) log(vk) +
˜ q(/vk)
∝ (1 − αvk)
−vk
˜ ηk
+ ( ˜φk− log(vk))
+ αvk
"
− φ0+ 1 + P
i eζk(i) 2
!
− vk−1
*
η0+|χ(i) − mk|2 2
+
˜ q(/vk)
#
, ✭✶✼✮
q(/vk)) = q(χ)q(w))q(z)Q
l6=vkq(ψl)✳
❇② ✐❞❡♥t✐✜❝❛t✐♦♥ ✇❡ ✜♥❞✿
φenk = (1 − αvk) eφk+ αvk
φ0+
P
iζek(i)
2
e
ηkn= 1−αηekvk + αvk η0+12P i eζk(i)
| emχ(i)|2+ eVχ(i) + m2k+ ˜τk2! ✭✶✽✮
✷✳✶✳✼ ▼❡❛♥s ♦❢ ❝❧❛ss❡s mk
log (eqn(mk)) ∝ (1 − αmk) log (eq(mk)) + αmk hlog (p (χ, w, z, ψ, y))iq(/m˜ k)
∝ (1 − αmk) e
τkm2k− 2eµkmk
+ αmk −
*1 2
X i
δ (z(i) = κ)
×
|χ(i) − mχ(i)|2 vk
+|mk− µ0| τ0
+
˜ q(/mk)
!
, ✭✶✾✮
✇✐t❤ q(/mk)) = q(χ)q(w))q(z)Q
l6=mkq(ψl)
❇② ✐❞❡♥t✐✜❝❛t✐♦♥✱ ✇❡ ♦❜t❛✐♥✿
e τkn=
"
(1 − αmk) eτk+ αmk
τ0−1+ v−1k P
i eζk(i)#−1
e
µnk = eτknh
(1 − αmk) eµk+ αmk
τek
µ0
τ0 + vk−1P
i eζk(i) emχ(i)i ✭✷✵✮
✸ ❚❤❡ ❢r❡❡ ♥❡❣❛t✐✈❡ ❡♥❡r❣②
❚❤❡ ❡✈❛❧✉❛t✐♦♥ ♦❢ t❤❡ ❢r❡❡ ♥❡❣❛t✐✈❡ ❡♥❡r❣② ❞✉r✐♥❣ t❤❡ ✐t❡r❛t✐♦♥ ♣r♦❝❡ss ❛❧❧♦✇s t♦ ❤❛✈❡ ❛♥ ✐♥❞✐❝❛t♦r ♦♥ t❤❡ ❝♦♥✈❡r❣❡♥❝❡
♦❢ t❤❡ ❛❧❣♦r✐t❤♠✳ ■♥❞❡❡❞✱ ✐ts ✈❛❧✉❡ ❛t t❤❡ ❝♦♥✈❡r❣❡♥❝❡ ❛❧❧♦✇s ❢♦r ❛♥ ❡st✐♠❛t❡ ♦❢ t❤❡ ❡✈✐❞❡♥❝❡ t❤❛t t❤❡ ♠♦❞❡❧ ✐s ✉s❡❢✉❧
❢♦r t❤❡ ❝❤♦✐❝❡ ♦❢ t❤❡ ❧❛tt❡r✳ ■♥ t❤❡ ♥♦♥❧✐♥❡❛r ❝❛s❡✱ t❤❡ ❢r❡❡ ♥❡❣❛t✐✈❡ ❡♥❡r❣② ✐s ❣✐✈❡♥ ❜②✿
F(q) = hp(y, χ, w, z, ψ|M)iq + H(q(χ, w, z, ψ)) ✭✷✶✮
✇❤❡r❡ H ✐s t❤❡ ❡♥tr♦♣② ♦❢ q ❛♥❞ ✐s ❣✐✈❡♥ ❜②✿
✽
H(q(χ, w, z, ψ)) = X
Nv
X
Nf
X
NP
X i
X
k
logp
2πeevw(i)
+X
i X
k
logq
2πeevχ(i)
+ X
i X
k
ζ˜κ(i) λ X j∈V(i)
ζ˜k(j) − log X
k
exp
λ X j∈V(i)
ζ˜k(j)
!
+ X
κ
logp 2πeeτκ
+X
k
e
ηk+ log
φekΓ(eηk)
− (1 + eηk)Ψ(eηk)
!
+ ηeǫ+ log
φeǫΓ(eηǫ)
− (1 + eηǫ)Ψ(eηǫ) + eηξ+ log
φeξΓ(eηξ)
− (1 + eηξ)Ψ(eηξ), ✭✷✷✮
❍❡♥❝❡✿
hp(y, χ, w, z, ψ)iq = −M + N (1 + NP) + K
2 log(2π) + (φǫ− 1) log (ηǫ) − Γ(φǫ)
− M + 2φǫ+ 2 2
Ψ(eηǫ) − log( eφǫ)
− ηǫv−1ǫ + (φξ− 1) log (ηξ) − Γ(φξ)
− N NvNPNf+ 2φξ+ 2 2
Ψ(eηξ) − log( eφξ)
− ηξvξ−1+ log(ηK(φ0 0−1))
− X
k
2φ0+ 1 +P
i eζk(i)
Ψ(eηk) − log(fφk)
− 2η0v−1k
2 − K Γ(φ0)
− X
k
e
m2k+ eτk+ µ20− 2 emkµ0
2τ0
+ λX i
X
k
ζek(i) X j∈V(i)
ζek(j) −vǫ−1
2
× ||y||22+ ||Gofmw||22− 2ytGomfw+ || eVwΓo||1
!
− vξ−1
2 ||fmw||22+ || eVw||1+
f mχ+ eVχ
E2
1− 2fmHχw◦ E∗
!
− X
i X
k
vk−1ζek(i)
| emχ(i)|22+ evχ(i) + em†2χ(i) − 2 emχ(i) em†χ(i)
2 , ✭✷✸✮
❲❡ ♠❛② ♥♦t❡ t❤❛t t❤❡ ❝♦♠♣✉t❛t✐♦♥ ♦❢ t❤❡ ❢r❡❡ ♥❡❣❛t✐✈❡ ❡♥❡r❣② ❞❡♣❡♥❞s ♠❛✐♥❧② ✐♥ t❡r♠s ✉s❡❞ t♦ ✉♣❞❛t❡ t❤❡ ✈❛❧✉❡s
♦❢ t❤❡ ♣❛r❛♠❡t❡rs ❛♥❞ ✐ts ❡✈❛❧✉❛t✐♦♥ ❞♦❡s ♥♦t r❡q✉✐r❡ ❛ ❝♦st ♦❢ ❛❞❞✐t✐♦♥❛❧ ❝♦♠♣✉t❛t✐♦♥✳
✹ ❖♣t✐♠❛❧ st❡♣ ✈❛❧✉❡s ❝♦♠♣✉t❛t✐♦♥
❇② ❡①❛♠✐♥✐♥❣ ❡q✉❛t✐♦♥s ✭✾✮✱ ✭✶✶✮✱ ✭✶✷✮✱ ✭✶✹✮✱ ✭✶✻✮✱ ✭✶✽✮✱ ✭✷✵✮✱ ✇❡ r❡♠❛r❦ t❤❛t t❤❡r❡ ✐s ♥♦ ❞❡♣❡♥❞❡♥❝❡ ❜❡t✇❡❡♥ ❡❧❡♠❡♥ts
♦❢ t❤❡ s❛♠❡ ❣r♦✉♣ ❢♦r χ✱ z✱ vǫ✱ vξ✱ vk ❛♥❞ mk✱ ✇❤❡r❡❛s t❤❡ ✉♣❞❛t❡ ♦❢ t❤❡ ♠❡❛♥ ✈❛❧✉❡ ♦❢ t❤❡ ❝♦♥tr❛st s♦✉r❝❡ fmnw❛t t❤❡
✐t❡r❛t✐♦♥ n ❞❡♣❡♥❞s ♦♥ t❤❡ ♠❡❛♥ ✈❛❧✉❡ fmw✳ ❚❤❡♥ t❤❡ ❣r❛❞✐❡♥t st❡♣s αρ✱ ρ = χ, z, vǫ, vξ, mk, vk ❝❛♥ ❜❡ s❡t t♦ ✶ ✐♥
♦r❞❡r t♦ ❛❝❝❡❧❡r❛t❡ t❤❡ ❝♦♥✈❡r❣❡♥❝❡ ❛♥❞ ♦♥❧② t❤❡ ❝♦♥tr❛st s♦✉r❝❡ ✉♣❞❛t✐♥❣ st❡♣ αw✐s ❝♦♠♣✉t❡❞✳ ❚❤✐s st❡♣ ✐s ❝♦♠♣✉t❡❞
✐♥ ❛♥ ♦♣t✐♠❛❧ ✇❛② ✐♥ ♦r❞❡r t♦ ❡♥s✉r❡ ❛ ❢❛st ❝♦♥✈❡r❣❡♥❝❡ ♦❢ t❤❡ s❤❛♣✐♥❣ ♣❛r❛♠❡t❡r t♦✇❛r❞s t❤❡✐r ✜♥❛❧ ✈❛❧✉❡s✳ ❚❤✐s ✐s
❞♦♥❡ ❢r♦♠ t❤❡ ♥❡❣❛t✐✈❡ ❢r❡❡✲❡♥❡r❣② ❢✉♥❝t✐♦♥ ❜② ♠❡❛♥s ♦❢ ❛ ◆❡✇t♦♥✬s ♠❡t❤♦❞✳ ❚❤❡ ♦♣t✐♠❛❧ st❡♣ t❤❡♥ r❡❛❞s✿
αoptw = ∆F(αw)/∆2F(αw) αw=0
, ✭✷✹✮
✇✐t❤ ∆F = ∂F/∂αw ❡t ∆2F = ∂2F/∂2αw
❇❡❢♦r❡ ❛♣♣❧②✐♥❣ t❤❡ ◆❡✇t♦♥ ♠❡t❤♦❞✱ ✇❡ r❡✇r✐t❡ t❤❡ ✉♣❞❛t❡ ❡q✉❛t✐♦♥s ❢♦r w ✇✐t❤ ♠♦r❡ ❝♦♥✈❡♥✐❡♥t ♥♦t❛t✐♦♥s✿
✾
Venw=
"
(1 − αw) eV−1w + α Rw
#−1
f
mnw=fmw+ αw Venwdw
✭✷✺✮
✇❤❡r❡ Rw=❉✐❛❣
vǫ−1Γo+ v−1ξ Γxc
❛♥❞ dw=
"
v−1ǫ GoH(y − Gofmw) + vξ−1 f
mχEinc− GcH f m2χ+ eVχ
Einc
− fmw+fmχGcfmw+ GcHmf∗χfmw− GcH f m2χ+ eVχ
Gcfmw
#
✳
❚❤❡♥✱ ✇❡ r❡✇r✐t❡ t❤❡ ♥❡❣❛t✐✈❡ ❢r❡❡ ❡♥❡r❣② ❛s ❛ ❢✉♥❝t✐♦♥ ♦❢ αw ✐♥ ♦r❞❡r t♦ ✉s❡ ✐t t♦ ♦❜t❛✐♥ t❤❡ ♦♣t✐♠❛❧ ✈❛❧✉❡✳ ■t r❡❛❞s✿
F(αw) = −vǫ−1
2 ||y||22+ ||Gomfw||22− 2ytGofmw+ || eVwΓo||1
!
−vξ−1
2 ||fmw||22+ || eVw||1
+
f mχ+ eVχ
E2
1− 2fmHχw◦ E∗
!
+X
i
logp
2πeevw(i) ,
✭✷✻✮
❚❤❡♥✱ ✇❡ ❝❛❧❝✉❧❛t❡ t❤❡ ✜rst ❛♥❞ t❤❡ s❡❝♦♥❞ ❞❡r✐✈❛t✐✈❡s t❤❛t ②✐❡❧❞ t❤❡ ❢♦❧❧♦✇✐♥❣✿
∂F(αw)
∂αw
= mf′w dtw+X
i
ev′w(i)
2 evw(i)− ev′w(i)rw(i), ✭✷✼✮
∂2F(αw)
∂2αw
= fm′′w dtw+fm′w dtw′ +X
i
evw′′(i)evw(i) − (evw′ (i))2
2 (evw(i))2 − evw′′(i)rw(i). ✭✷✽✮
✇❤❡r❡ vw(i)❛♥❞ rw(i)st❛♥❞ r❡s♣❡❝t✐✈❡❧② ❢♦r ❞✐❛❣♦♥❛❧ ❡❧❡♠❡♥ts i ♦❢ ♠❛tr✐① Vw ❛♥❞ Rw✱ ❛♥❞
Ve′nw =
Venw2
Ve−1w − Rw
Ve′′nw = Venw3
Ve−1w − Rw
2
f
m′nw = eVnwdw+ α eV′nwdw
f
m′′nw = 2 eV′nwdw+ α eV′′nw dw
✭✷✾✮
t❤❡♥ t❤❡ ♦♣t✐♠❛❧ ✈❛❧✉❡ ✐♥ t❤✐s ❝❛s❡ ❜❡❝♦♠❡s
αoptw = dtwmf′w0+12P
is2wi f
m′′w0 dtw+fm′w0 dtw′ +12P
is3wi ✭✸✵✮
✇❤❡r❡
∂ fmw
∂αw
αw=0
=fm′w0= eVw0dw
∂2mfw
∂2αw
αw=0
=fm′′w0= 2 eV′w0dw
∂ fVw
∂αw
αw=0
= eV′w0= − eVw0Sw
✭✸✶✮
❛♥❞
dtw′ = mf′wt v−1ǫ GoGH− vξ−1
1 −mfχGc− GcHfm∗χ− GcH(fmχ+ eVχ)Gc!t
,
swi = rwievw0i− 1. ✭✸✷✮
✶✵
❘❡❢❡r❡♥❝❡s
❬✶❪ ❱✳ ❙♠í❞❧ ❛♥❞ ❆✳ ◗✉✐♥♥✱ ❚❤❡ ❱❛r✐❛t✐♦♥❛❧ ❇❛②❡s ▼❡t❤♦❞ ✐♥ ❙✐❣♥❛❧ Pr♦❝❡ss✐♥❣✱ ❙♣r✐♥❣❡r ❱❡r❧❛❣✱ ❇❡r❧✐♥✱ ✷✵✵✻✳
❬✷❪ ❍✳ ❆②❛ss♦✱ ❇✳ ❉✉❝❤ê♥❡✱ ❛♥❞ ❆✳ ▼♦❤❛♠♠❛❞✲❉❥❛❢❛r✐✱ ✏❖♣t✐❝❛❧ ❞✐✛r❛❝t✐♦♥ t♦♠♦❣r❛♣❤② ✇✐t❤✐♥ ❛ ✈❛r✐❛t✐♦♥❛❧ ❇❛②❡s✐❛♥
❢r❛♠❡✇♦r❦✱✑ ■♥✈❡rs❡ Pr♦❜❧❡♠s ✐♥ ❙❝✐❡♥❝❡ ❛♥❞ ❊♥❣✐♥❡❡r✐♥❣✱ ✈♦❧✳ ✷✵✱ ♥♦✳ ✶✱ ♣♣✳ ✺✾✕✼✸✱ ✷✵✶✷✳
❬✸❪ ▲✳ ●❤❛rs❛❧❧✐✱ ❍✳ ❆②❛ss♦✱ ❇✳ ❉✉❝❤ê♥❡✱ ❛♥❞ ❆✳ ▼♦❤❛♠♠❛❞✲❉❥❛❢❛r✐✱ ✏▼✐❝r♦✇❛✈❡ t♦♠♦❣r❛♣❤② ❢♦r ❜r❡❛st ❝❛♥❝❡r
❞❡t❡❝t✐♦♥ ✇✐t❤✐♥ ❛ ✈❛r✐❛t✐♦♥❛❧ ❇❛②❡s✐❛♥ ❛♣♣r♦❛❝❤✱✑ ✐♥ ■❊❊❊ ❊✉r♦♣❡❛♥ ❙✐❣♥❛❧ Pr♦❝❡ss✐♥❣ ❈♦♥❢❡r❡♥❝❡ ✭❊❯❙■P❈❖✮✱
▼❛rr❛❦❡❝❤✱ ▼❛r♦❝❝♦✱ ✷✵✶✸✳
❬✹❪ ▲✳ ●❤❛rs❛❧❧✐✱ ❍✳ ❆②❛ss♦✱ ❇✳ ❉✉❝❤ê♥❡✱ ❛♥❞ ❆✳ ▼♦❤❛♠♠❛❞✲❉❥❛❢❛r✐✱ ✏❆ ❣r❛❞✐❡♥t✲❧✐❦❡ ✈❛r✐❛t✐♦♥❛❧ ❇❛②❡s✐❛♥ ❛♣♣r♦❛❝❤✿
❛♣♣❧✐❝❛t✐♦♥ t♦ ♠✐❝r♦✇❛✈❡ ✐♠❛❣✐♥❣ ❢♦r ❜r❡❛st t✉♠♦r ❞❡t❡❝t✐♦♥✱✑ s✉❜♠✐tt❡❞ ✐♥ ■❊❊❊ ■♥t❡r♥❛t✐♦♥❛❧ ❈♦♥❢❡r❡♥❝❡ ♦♥
■♠❛❣❡ Pr♦❝❡ss✐♥❣ ✭■❈■P✮✱ ❋r❛♥❝❡✱ P❛r✐s✱ ✷✵✶✹✳
❬✺❪ ❆✳ ❋r❛②ss❡ ❛♥❞ ❚✳ ❘♦❞❡t✱ ✏❆ ♠❡❛s✉r❡✲t❤❡♦r❡t✐❝ ✈❛r✐❛t✐♦♥❛❧ ❜❛②❡s✐❛♥ ❛❧❣♦r✐t❤♠ ❢♦r ❧❛r❣❡ ❞✐♠❡♥s✐♦♥❛❧ ♣r♦❜❧❡♠s✱✑
❚❡❝❤✳ ❘❡♣✳ ❤❛❧✲✵✵✼✵✷✷✺✾✱ ❤tt♣✿✴✴❤❛❧✳❛r❝❤✐✈❡s✲♦✉✈❡rt❡s✳❢r✴❞♦❝s✴✵✵✴✼✵✴✷✷✴✺✾✴P❉❋✴✈❛r❴❜❛②❱✽✳♣❞❢✱ ✷✵✶✷✳
❬✻❪ ❲✳ ❈✳ ●✐❜s♦♥✱ ❚❤❡ ▼❡t❤♦❞ ♦❢ ▼♦♠❡♥ts ✐♥ ❊❧❡❝tr♦♠❛❣♥❡t✐❝s✱ ❈❤❛♣♠❛♥ ✫ ❍❛❧❧✴❈❘❈✱ ❇♦❝❛ ❘❛t♦♥✱ ✷✵✵✼✳
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