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Small W 0 near the Conifold Max Brinkmann String Phenomenology Seminar Series 06.10.2020

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Page 1: Small W0 neartheConifold

Small W0 near the Conifold

Max Brinkmann

String Phenomenology Seminar Series

06.10.2020

Page 2: Small W0 neartheConifold

The Big Picture

[adapted from Eran Palti’s review, 1903.06239]

Where does dS lie in this picture?

Max Brinkmann Small W0 near the Conifold 1/251/25

Page 3: Small W0 neartheConifold

The Little Picture

[adapted from Eran Palti’s review, 1903.06239]

Where does KKLT lie in this picture?

Max Brinkmann Small W0 near the Conifold 1/251/25

Page 4: Small W0 neartheConifold

KKLT – a recipe for dS

CS moduli stabilizedat |W0| ≪ 1

nonpert. effects110 120 130 140 150 160

-2.×10-15

-1.×10-15

1.×10-15

2.×10-15AdS vacuum

strong warping(conifold)

small D3 uplift

110 120 130 140 150 160

1.5×10-15

2.×10-15

2.5×10-15

3.×10-15dS vacuum

Max Brinkmann Small W0 near the Conifold 2/252/25

Page 5: Small W0 neartheConifold

KKLT – a recipe for dS [Kachru,Kallosh,Linde,Trivedi ’03]

CS moduli stabilizedat |W0| ≪ 1

nonpert. effects110 120 130 140 150 160

-2.×10-15

-1.×10-15

1.×10-15

2.×10-15AdS vacuum

strong warping(conifold)

small D3 uplift

110 120 130 140 150 160

1.5×10-15

2.×10-15

2.5×10-15

3.×10-15dS vacuum

[statistics: Douglas et al ’04/’05][Demirtas,Kim,McAllister,Moritz ’19]

[Sethi ’17][Moritz,Retolaza,Westphal ’17][Gautason,Van Hemelryck,Van Riet ’19][ Kallosh,Linde,McDonough,Scalisi ’18][Hamada,Hebecker,Shiu,Soler ’18][Carta,Moritz,Westphal ’19][Blumenhagen,M.B.,Makridou ’20]

[Klebanov,Strassler ’00][Giddings,Kachru,Polchinski ’02][Douglas,Shelton,Torroba ’07][Blumenhagen,Herschmann,Wolf ’16]

[Bena,Graña,Halmagy ’10][Michel,Mintun,Polchinski,Puhm,Saad ’14][Bena,Dudas,Graña,Lüst ’18][Blumenhagen,Kläwer,Schlechter ’19]

[...and many, many more!]

Max Brinkmann Small W0 near the Conifold 2/252/25

Page 6: Small W0 neartheConifold

KKLT – a recipe for dS

CS moduli stabilizedat |W0| ≪ 1

nonpert. effects110 120 130 140 150 160

-2.×10-15

-1.×10-15

1.×10-15

2.×10-15AdS vacuum

strong warping(conifold)

small D3 uplift

110 120 130 140 150 160

1.5×10-15

2.×10-15

2.5×10-15

3.×10-15dS vacuum

[Álvarez-García,Blumenhagen,M.B.,Schlechter ’20]

[Demirtas,Kim,McAllister,Moritz ’20]

[Demirtas,Kim,McAllister,Moritz ’19]

Max Brinkmann Small W0 near the Conifold 2/252/25

Page 7: Small W0 neartheConifold

KKLT – a recipe for dS

CS moduli stabilizedat |W0| ≪ 1

nonpert. effects110 120 130 140 150 160

-2.×10-15

-1.×10-15

1.×10-15

2.×10-15AdS vacuum

strong warping(conifold)

small D3 uplift

110 120 130 140 150 160

1.5×10-15

2.×10-15

2.5×10-15

3.×10-15dS vacuum

[Álvarez-García,Blumenhagen,M.B.,Schlechter ’20]

[Demirtas,Kim,McAllister,Moritz ’20]

[Demirtas,Kim,McAllister,Moritz ’19]

KKLT and the Swampland Conjectures[Blumenhagen,M.B.,Makridou ’20]

Max Brinkmann Small W0 near the Conifold 2/252/25

Page 8: Small W0 neartheConifold

A recipe for |W0| ≪ 1

Idea: natural hierarchiesSmall values can naturally be generated by perturbative mechanisms, ifthe leading term vanishes analytically.

The prepotential of the complex structure moduli splits into a classicaland a nonperturbative part, if they are• at weak string coupling,• at large complex structure,• expressed in terms of the mirror variables.

To-Do List1. Find fluxes that solve pert. F-term eq. for vanishing superpotential.

2. Generate a small nonpert. potential for the remaining flat direction.

Max Brinkmann Small W0 near the Conifold 3/253/25

Page 9: Small W0 neartheConifold

A recipe for |W0| ≪ 1

Idea: natural hierarchiesSmall values can naturally be generated by perturbative mechanisms, ifthe leading term vanishes analytically.

The prepotential of the complex structure moduli splits into a classicaland a nonperturbative part, if they are• at weak string coupling,• at large complex structure,• expressed in terms of the mirror variables.

To-Do List1. Find fluxes that solve pert. F-term eq. for vanishing superpotential.

2. Generate a small nonpert. potential for the remaining flat direction.

Max Brinkmann Small W0 near the Conifold 3/253/25

Page 10: Small W0 neartheConifold

A recipe for |W0| ≪ 1

Setup• Orientifold X of a CY 3-fold.• Wrapped by D7-branes carrying −QD3.

• Period vector Π =(

Ua

Fa

)w/ sympl. pairing Σ =

(0 −11 0

).

• Prepotential F s.th. Fa = ∂UaF .• Inhomogeneous coordinates: U0 = 1, F0 = 2F − U iFi .

The prepotential splits into F(U) = Fpert(U) + Finst(U).

Including the axio-dilaton:

K = − log(−i Π†ΣΠ) − log(S + S) ,W = (F + i SH)T · Σ · Π .

Max Brinkmann Small W0 near the Conifold 4/254/25

Page 11: Small W0 neartheConifold

A recipe for |W0| ≪ 1

Perturbative Prepotential

Fpert(U) = − 13!KabcUaUbUc + 1

2aabUaUb + baUa + ξ

with• Kabc the triple intersection numbers of the mirror CY,

• ξ = − ζ(3)χ2(2πi)3 , and χ the Euler number of the mirror CY,

• aab, ba rational numbers related to the mirror CY.

Max Brinkmann Small W0 near the Conifold 5/255/25

Page 12: Small W0 neartheConifold

A recipe for |W0| ≪ 1

Lemma: existence of a perturbatively flat vacuum

If a pair (M⃗, K⃗ ) ∈ Zn × Zn satisfies: Then:

−12M⃗ · K⃗ ≤ QD3, The tadpole bound is satisfied,

Nab = KabcMc is invertible, ∂W = 0 has solution U⃗ = p⃗S ,

K⃗T N−1K⃗ = 0, W = 0 in that solution,

p⃗ = N−1K⃗ lies in the Kähler cone, the minimum is trustable

a · M⃗ and b⃗ · M⃗ are integer-valued. and the fluxes are integer valued.[Demirtas,Kim,McAllister,Moritz ’19]

The appropriate choice of fluxes is given by

F = (b⃗ · M⃗, a · M⃗, 0, M⃗)T ,H = (0, K⃗ , 0, 0)T ,

s.th. the superpotential is hom. of deg. 2 in the U i .

Max Brinkmann Small W0 near the Conifold 6/256/25

Page 13: Small W0 neartheConifold

A recipe for |W0| ≪ 1

Instanton Contributions

Finst(U) ∼∑

q⃗e2πi q⃗·U⃗

with the sum running over effective curves.

Stabilizing the axio-dilaton: Racetrack

In the perturbative minimum: U⃗ = p⃗S .

Weff(S) ∼ Ma∂aFinst ∼∑

q⃗e2πiSp⃗ ·⃗q

This stabilizes S to exponentially small values if the two leadinginstanton contributions satisfy p⃗ · q⃗1 ≈ p⃗ · q⃗2.

Max Brinkmann Small W0 near the Conifold 7/257/25

Page 14: Small W0 neartheConifold

What’s next?

CS moduli stabilizedat |W0| ≪ 1

nonpert. effects110 120 130 140 150 160

-2.×10-15

-1.×10-15

1.×10-15

2.×10-15AdS vacuum

strong warping(conifold)

small D3 uplift

110 120 130 140 150 160

1.5×10-15

2.×10-15

2.5×10-15

3.×10-15dS vacuum

Max Brinkmann Small W0 near the Conifold 8/258/25

Page 15: Small W0 neartheConifold

Periods at the Conifold

The hardest part is finding the periods/prepotential at the conifold!

Method 1: Resumming with GV-nilpotent curves+ Elegantly avoid complete computation.

- Only special cases: conifold cycle mirror to shrinking curve.

- No full solution, only good approximation.

[Demirtas,Kim,McAllister,Moritz ’20]

Method 2: analytic computation of transition matrices+ Fairly general method

+ Complete solution, can check approximations numerically

- Fairy involved computations

[Álvarez-García,Blumenhagen,M.B.,Schlechter ’20; Lorenz’ talk]

Max Brinkmann Small W0 near the Conifold 9/259/25

Page 16: Small W0 neartheConifold

Periods at the Conifold

Transition MatrixPeriods in a symplectic basis hard to compute. Solving the Picard-Fuchsequations Di ω = 0 in any local basis is easy.

Π = m · ω

At LCS, monodromies fix the transition matrix m uniquely. At theconifold monodromies are not enough.

We can rewrite the fundamental period at the LCS as a hypergeometricfunction, which allowed us to analytically determine the transitionmatrix.

Max Brinkmann Small W0 near the Conifold 10/2510/25

Page 17: Small W0 neartheConifold

Periods at the Conifold

Transition MatrixPeriods in a symplectic basis hard to compute. Solving the Picard-Fuchsequations Di ω = 0 in any local basis is easy.

Π = m · ω

At LCS, monodromies fix the transition matrix m uniquely. At theconifold monodromies are not enough.

With the analytic transition matrix we can efficiently compute theperiods at the conifold to very high order (30+), as well as theprepotential and mirror maps. (Lorenz’ talk)

Max Brinkmann Small W0 near the Conifold 10/2510/25

Page 18: Small W0 neartheConifold

|W0| ≪ 1 at conifold

Setup• n-parameter CY orientifold• One modulus close to the conifold, others at LCS

Notation: X 0 = 1, X i = (Uα, Z )T , (i = 1, ... , n), (α = 1, ... , n − 1)

Prepotential

Fpert = − 13!KijkX iX jX k + 1

2AijX iX j + BiX i + C − Z 2 log Z2πi ,

Finst = 1(2πi)3

∑c⃗

ac⃗

n∏i=1

qini ,

Note that while the qi are still simply exponentials in the LCS moduli,the conifold modulus enters linearly!

Max Brinkmann Small W0 near the Conifold 11/2511/25

Page 19: Small W0 neartheConifold

|W0| ≪ 1 at conifold

Setup• n-parameter CY orientifold• One modulus close to the conifold, others at LCS

Notation: X 0 = 1, X i = (Uα, Z )T , (i = 1, ... , n), (α = 1, ... , n − 1)

Prepotential

Fpert = − 13!KijkX iX jX k + 1

2AijX iX j + BiX i + C − Z 2 log Z2πi ,

Finst = 1(2πi)3

∑c⃗

ac⃗

n∏i=1

qini ,

Note that while the qi are still simply exponentials in the LCS moduli,the conifold modulus enters linearly!

Max Brinkmann Small W0 near the Conifold 11/2511/25

Page 20: Small W0 neartheConifold

|W0| ≪ 1 at conifold

To-Do List1. Find fluxes that solve pert. eq. for vanishing superpotential at Z = 0.2. Stabilize conifold modulus at leading order to WZ = O(Z ).3. Include instanton corrections for the remaining flat direction.

Choosing FluxesWant the superpotential to be degree 2 in the LCS moduli:

F =

BiM i

(AiαM i , Mn)T

0M⃗

, H =

0K⃗00

, M⃗, K⃗ ∈ Zn

Max Brinkmann Small W0 near the Conifold 12/2512/25

Page 21: Small W0 neartheConifold

|W0| ≪ 1 at conifold

To-Do List1. Find fluxes that solve pert. eq. for vanishing superpotential at Z = 0.2. Stabilize conifold modulus at leading order to WZ = O(Z ).3. Include instanton corrections for the remaining flat direction.

Choosing FluxesWant the superpotential to be degree 2 in the LCS moduli:

F =

BiM i

(AiαM i , Mn)T

0M⃗

, H =

0K⃗00

, M⃗, K⃗ ∈ Zn

Max Brinkmann Small W0 near the Conifold 12/2512/25

Page 22: Small W0 neartheConifold

|W0| ≪ 1 at conifold

To-Do List1. Find fluxes that solve pert. eq. for vanishing superpotential at Z = 0.2. Stabilize conifold modulus at leading order to WZ = O(Z ).3. Include instanton corrections for the remaining flat direction.

Choosing FluxesWant the superpotential to be degree 2 in the LCS moduli:

F =

BiM i

(AiαM i , Mn)T

0M⃗

, H =

0K⃗00

, M⃗, K⃗ ∈ Zn

⇒ BiM i , AiαM i ∈ Z⇒ Bi , Aiα must be rational

Max Brinkmann Small W0 near the Conifold 12/2512/25

Page 23: Small W0 neartheConifold

|W0| ≪ 1 at conifold

Step 1: first order, Z=0Stabilizing the LCS moduli at the conifold locus:

W = 12NαβUαUβ + iSKαUα = 0 (N−1)αβKαKβ = 0

∂αW = 0 Uα = pαS

with Nαβ = KiαβM i and pα = −i(N−1)αβKβ .

Max Brinkmann Small W0 near the Conifold 13/2513/25

Page 24: Small W0 neartheConifold

|W0| ≪ 1 at conifold

Step 1: first order, Z=0Stabilizing the LCS moduli at the conifold locus:

W = 12NαβUαUβ + iSKαUα = 0 (N−1)αβKαKβ = 0

∂αW = 0 Uα = pαS

with Nαβ = KiαβM i and pα = −i(N−1)αβKβ .

⇒ Nαβ = KiαβM i invertible

Max Brinkmann Small W0 near the Conifold 13/2513/25

Page 25: Small W0 neartheConifold

|W0| ≪ 1 at conifold

Step 2: Stabilize ZIntegrating out the LCS moduli Uα:

Wpert(S, Z ) = −mZ log(Z )2πi + m1Z + n1SZ + O(Z 2) ,

DZ W = ∂Z W + ∂Z K · O(Z )

Max Brinkmann Small W0 near the Conifold 14/2514/25

Page 26: Small W0 neartheConifold

|W0| ≪ 1 at conifold

Step 2: Stabilize ZIntegrating out the LCS moduli Uα:

Wpert(S, Z ) = −mZ log(Z )2πi + m1Z + n1SZ + O(Z 2) ,

DZ W = ∂Z W + ∂Z K · O(Z )

⇒ Z0 = ζ0 e−2πpZ S , WZ = mZ2πi + O(Z 2)

Max Brinkmann Small W0 near the Conifold 14/2514/25

Page 27: Small W0 neartheConifold

|W0| ≪ 1 at conifold

Step 3: Instanton Contributions and RacetrackThe CS moduli are stabilized to log(Z ) ∼ Uα ∼ S .

Weff(S) = −M i∂iFinst + mZ2πi ∼

∑an ecnS .

That this can be stabilized to small W0 has to be checked case by case.

Max Brinkmann Small W0 near the Conifold 15/2515/25

Page 28: Small W0 neartheConifold

|W0| ≪ 1 at conifold - Example

Example: 3-parameter CY P1,1,2,8,12[24]

K111 = 8, K112 = 2, K113 = 4, K123 = 1, K133 = 2 ,

A33 =(1

2 + 3 − 2 log(2π)2πi

), B =

(236 , 1, 23

12

)T.

The leading instanton contributions are

Finst = −5i qU136π3 −

493 q2U1

10368π3 + 5i qU1qZ36π3 + ... ,

qU1 = 864 e2πiU1 , qU2 = 4(π

i Z )4 e2πiU2 , qZ = (πi Z )

Max Brinkmann Small W0 near the Conifold 16/2516/25

Page 29: Small W0 neartheConifold

|W0| ≪ 1 at conifold - Example

First ChecksBiM i , AiαM i ∈ Z ⇒ Bi , Aiα must be rational ✓

After steps 1 and 2: Z0 ≪ 1 for ℜ(S) ≫ 1 ✓

Choosing FluxesThe fluxes must be chosen to satisfy• BiM i , AiαM i ∈ Z,• Nαβ = KiαβM i invertible,• (N−1)αβKαKβ = 0,• Instanton series: 1 > |qi | ∼ |ef (M⃗,K⃗)S | ↔ f (M⃗,K⃗) < 0.

A simple search finds many reasonably small fluxes satisfying these.

Max Brinkmann Small W0 near the Conifold 17/2517/25

Page 30: Small W0 neartheConifold

|W0| ≪ 1 at conifold - Example

A concrete solution

Choosing M⃗ = (−24, 120, 24)T , K⃗ = (−9, 3, −4)T :

⟨U1⟩ = 2.79 i , ⟨U2⟩ = 8.36 i , ⟨Z ⟩ = 1.36 · 10−6i , ⟨S⟩ = 22.3 ,

|qi | = (2 · 10−5, 0.2, 4 · 10−6) ,

W0 = −3.10 · 10−6 .

22.0 22.5 23.0 23.5 24.0

5.×10-15

1.×10-14

1.5×10-14

2.×10-14

2.5×10-14

Max Brinkmann Small W0 near the Conifold 18/2518/25

Page 31: Small W0 neartheConifold

|W0| ≪ 1 at conifold - Example

MassesFull access to the Periods allows us to compute the masses.

{m2} = {6 · 1014︸ ︷︷ ︸Z

, 1 · 103, 3 · 102︸ ︷︷ ︸U i

, 2 · 10−11︸ ︷︷ ︸S

}M2pl .

Note that m2S ≈ |W0|2 ≈ m2

KKLT :The axio-dilaton cannot be integrated out before KKLT starts!

Search Results• Inexhaustive search over fluxes• Semianalytic computation, no numerical checks• O(104) vacua with |W0| ≤ 10−6

• More detailed search described by [Demirtas,Kim,McAllister,Moritz ’20]

Max Brinkmann Small W0 near the Conifold 19/2519/25

Page 32: Small W0 neartheConifold

|W0| ≪ 1 at conifold - Example

MassesFull access to the Periods allows us to compute the masses.

{m2} = {6 · 1014︸ ︷︷ ︸Z

, 1 · 103, 3 · 102︸ ︷︷ ︸U i

, 2 · 10−11︸ ︷︷ ︸S

}M2pl .

Note that m2S ≈ |W0|2 ≈ m2

KKLT :The axio-dilaton cannot be integrated out before KKLT starts!

Search Results• Inexhaustive search over fluxes• Semianalytic computation, no numerical checks• O(104) vacua with |W0| ≤ 10−6

• More detailed search described by [Demirtas,Kim,McAllister,Moritz ’20]

Max Brinkmann Small W0 near the Conifold 19/2519/25

Page 33: Small W0 neartheConifold

KKLT and the Swampland Conjectures

CS moduli stabilizedat |W0| ≪ 1

nonpert. effects110 120 130 140 150 160

-2.×10-15

-1.×10-15

1.×10-15

2.×10-15AdS vacuum

strong warping(conifold)

small D3 uplift

110 120 130 140 150 160

1.5×10-15

2.×10-15

2.5×10-15

3.×10-15dS vacuum

KKLT and the Swampland:The AdS Distance Conjecture

[Blumenhagen,M.B.,Makridou ’20]

Max Brinkmann Small W0 near the Conifold 20/2520/25

Page 34: Small W0 neartheConifold

AdS distance conjecture [Lüst, Palti, Vafa ’19]

AdS distance conjecture (ADC)For an AdS vacuum the limit Λ → 0 is at infinite distance in field spaceand there is a tower of light states with

mtower = cAdS |Λ|α

for α > 0. Supersymmetric vacua have α = 1/2.

• Usually this tower is assumed to be the KK-tower.• Satisfied by most treelevel vacua.• DGKT are counterexamples for the strong version!• Strong version forbids scale separation.• Is SUSY the wrong distinguishing feature for strong version?

Max Brinkmann Small W0 near the Conifold 21/2521/25

Page 35: Small W0 neartheConifold

KKLT: ADC

KKLT AdS minimum

A(2aτ + 3) = −3W0eaτ , Λ = −a2A2

6τe−2aτ .

ADC: what is the real KK scale?• Λ → 0 when τ → ∞, at infinite distance in field space. ✓• Naive KK scale: mKK ∼ 1/τ ≫ |Λ|α. ADC violated!?• Warped throat: KK modes near tip redshifted [Blumenhagen, Kläwer, Schlechter ’19]

m2KK ∼ 1

log2 |Λ||Λ|

13 .

• Up to log-corrections, ADC satisfied with α = 1/6. ✓• Since α < 1/2, scale separation is possible.

Max Brinkmann Small W0 near the Conifold 22/2522/25

Page 36: Small W0 neartheConifold

Other quantum vacua: LVS

We find very similar behavior for the large volume scenario:

LVS AdS minimum

VLVS = λ

√τse−2aτs

V− µ

τse−aτs

V2 + ν

V3 , Λ ∼ −e−3aτs

τs

(1 + O( 1

τs))

.

ADC: satisfied with α = 2/9 up to log-corrections ✓• Λ → 0 as τs → ∞. ✓• For LVS, no constraint on W0 to be small, naive KK-scale justified:

m2KK ∼ 1

V43

∼ 1

τ23s

e− 43 aτs ∼ 1

log29 |Λ|

|Λ|49 .

Max Brinkmann Small W0 near the Conifold 23/2523/25

Page 37: Small W0 neartheConifold

Log-Corrections to Swampland Conjectures

ADC - classicalThe limit Λ → 0 is at infinite distance in field space and there is a tower oflight states with

mtower = cAdS |Λ|α

for α > 0. Supersymmetric vacua have α = 1/2.

Max Brinkmann Small W0 near the Conifold 24/2524/25

Page 38: Small W0 neartheConifold

Log-Corrections to Swampland Conjectures

ADC - quantumThe limit Λ → 0 is at infinite distance in field space and there is a tower oflight states with

mtower = cAdS |Λ|α 1log |Λ|β

for α, β > 0. Vacua without dilute flux limit have α = 1/2.

Max Brinkmann Small W0 near the Conifold 24/2524/25

Page 39: Small W0 neartheConifold

Summary

• KKLT is a recipe for dS which has never actually been cooked.• Understanding the interplay between ingredients is important.• We have shown that small |W0| can be found near a conifold.• Progress has shown no big holes in the argument yet.• However, KKLT violates AdS and dS swampland conjectures.• Intrinsically quantum in nature – can this be the reason?

Max Brinkmann Small W0 near the Conifold 25/2525/25

Page 40: Small W0 neartheConifold

Thank you for your attention!

Page 41: Small W0 neartheConifold
Page 42: Small W0 neartheConifold

IIA flux vacua - DGKT

• Closed string moduli stabilized via RR, H3 fluxes• Dilute flux limit exists

Example: isotropic 6-torus; moduli S , T =Tk , U =Uk

• W = if0T 3 − 3if4T + ih0S + 3ih1U• KK scales: m2

KK,i ∼ |Λ|7/9 (weak) ADC ✓

This minimum is supersymmetric, strong ADC is violated!

Max Brinkmann Small W0 near the Conifold 1/251/25

Page 43: Small W0 neartheConifold

IIA flux vacua - Freund-Rubin

• Backreaction of fluxes on the geometry important• Encoded by geometric fluxes• No dilute flux limit

Example: isotropic 6-torus; moduli S , T =Tk , U =Uk

• W = f6 + 3f2T 2 − ω0ST − 3ω1UT• (naive) KK scales: m2

KK,1 ∼ |Λ|ω2

1, m2

KK,2 ∼ |Λ|ω1ω2

• Looks like ωi allow for scale separation!

Max Brinkmann Small W0 near the Conifold 2/252/25

Page 44: Small W0 neartheConifold

IIA flux vacua - Freund-Rubin

• Backreaction of fluxes on the geometry important• Encoded by geometric fluxes• No dilute flux limit

Example: isotropic 6-torus; moduli S , T =Tk , U =Uk

• W = f6 + 3f2T 2 − ω0ST − 3ω1UT• Must take backreaction into account! [Font, Herráez, Ibáñez ’19]

• KK scales: m2KK,i ∼ |Λ| strong ADC ✓

Difference between these models are flux backreactions on thegeometry, i.e geometric fluxes. Is this the relevant feature fordistinguishing strong/weak ADC cases?

Max Brinkmann Small W0 near the Conifold 2/252/25