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On Mean curvature flow of Singular Non compact cases Riemannian - - PowerPoint PPT Presentation

On Mean curvature flow of Singular Riemannian foliations: On Mean curvature flow of Singular Non compact cases Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Marcos M. Alexandrino


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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

On Mean curvature flow of Singular Riemannian foliations: Non compact cases

Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. [ACG19] Marcos M. Alexandrino, Leonardo F. Cavenaghi and Icaro Gonçalves, Mean curvature flow of singular Riemannian foliations: Non compact cases, arXiv:1909.04201 (2019)

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Definition

Given a Riemannian manifold M and an immersion ϕ : L0 → M, a smooth family of immersions ϕt : L0 → M, t ∈ [0, T) is called a solution of the mean curvature flow (MCF for short) if ϕt satisfies the evolution equation d dt ϕt(x) = H(t, x), where H(t, x) is the mean curvature of L(t) := ϕt(L0).

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Definition

A submanifold L of a space form M(k) is called isoparametric if its normal bundle is flat and the principal curvatures along any parallel normal vector field are constant. An isoparametric foliation F on M(k) is a partition of M(k) by submanifolds parallel to a given isoparametric submanifold L. Jurgen Berndt, Sergio Console, Carlos Enrique Olmos Submanifolds and Holonomy Chapman & Hall/CRC Monographs and Research Notes in Mathematics(2003)

  • G. Thorbergsson, Singular Riemannian Foliations and

Isoparametric Submanifolds Milan J. Math. Vol. 78 (2010) 355–370

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Definition

A singular foliation F = {L} is called a generalized isoparametric if

1 F is Riemannian, i.e., every geodesic perpendicular to one

leaf is perpendicular to every leaf it meets.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Definition

A singular foliation F = {L} is called a generalized isoparametric if

1 F is Riemannian, i.e., every geodesic perpendicular to one

leaf is perpendicular to every leaf it meets.

2 the mean curvature field

H is basic in the principal stratum M0

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Definition

A singular foliation F = {L} is called a generalized isoparametric if

1 F is Riemannian, i.e., every geodesic perpendicular to one

leaf is perpendicular to every leaf it meets.

2 the mean curvature field

H is basic in the principal stratum M0 Examples:

1 F = {G(x)}x∈M, where G is Lie subgroup of Iso(M) 2 isoparametric foliations, 3 Singular Riemannian foliations with compact leaves on Rn,

Sn and projective spaces (see Clifford foliations for non homogenous examples).

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Example (Holonomy foliations)

  • L is a Riemannian manifold ,
  • E is a Euclidean vector bundle over L (i.e., with an inner

product , p on each fiber Ep)

  • ∇E is a metric connection on E, i.e.

Xξ, η = ∇E

Xξ, η + ξ, ∇E Xη.

  • the connection (Sasaki) metric gE on E

Define the holonomy foliation Fh on E, by declaring two vectors ξ, η ∈ E in the same leaf if they can be connected to

  • ne another via a composition of parallel transports (with

respect to ∇E).

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Example (Model)

Consider a Euclidean vector bundle Rn → E → L, with a metric connection ∇E and a the Sasaki metric gE. Let F0

p = {L0 ξ}ξ∈Ep

be a SRF with compact leaves on the fiber Ep. Assume F0 is invariant by the the holonomy group Hp at p i.e., the group sends leaves to leaves.

  • F = {Lξ}ξ∈Ep with leaves Lξ = H(L0

ξ) where H is the

holonomy groupoid associate to the connection ∇E.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Example (Model)

Consider a Euclidean vector bundle Rn → E → L, with a metric connection ∇E and a the Sasaki metric gE. Let F0

p = {L0 ξ}ξ∈Ep

be a SRF with compact leaves on the fiber Ep. Assume F0 is invariant by the the holonomy group Hp at p i.e., the group sends leaves to leaves.

  • F = {Lξ}ξ∈Ep with leaves Lξ = H(L0

ξ) where H is the

holonomy groupoid associate to the connection ∇E. ACG19 + Alexandrino, Inagaki, Struchiner(18) imply

Lemma (Semi-local Model)

Let F be a SRF with closed leaves. Then F|Tubǫ(Lq) is foliated diffeomorphic to the foliation defined in Model. Therefore Tubǫ(Lq) admits a metric so that F|Tubǫ(Lq) is a generalized isoparametric foliation.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Theorem A (ACG19)

Let F := {L} be a generalized isoparametric foliation with closed leaves on a complete manifold M so that M/F is

  • compact. Let L0 ∈ F be a regular leaf of M and let L(t) denote

the MCF evolution of L0. Assume that T < ∞. Then:

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Theorem A (ACG19)

Let F := {L} be a generalized isoparametric foliation with closed leaves on a complete manifold M so that M/F is

  • compact. Let L0 ∈ F be a regular leaf of M and let L(t) denote

the MCF evolution of L0. Assume that T < ∞. Then: (a) L(t) converges to a singular leaf LT of F.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Theorem A (ACG19)

Let F := {L} be a generalized isoparametric foliation with closed leaves on a complete manifold M so that M/F is

  • compact. Let L0 ∈ F be a regular leaf of M and let L(t) denote

the MCF evolution of L0. Assume that T < ∞. Then: (a) L(t) converges to a singular leaf LT of F. (b) If the curvature of M is bounded and the shape operator along each leaf is bounded, then ϕt(p) converges to a point of LT, for each p ∈ L(0). In addition the singularity is of type I, i.e., lim sup

t→T − At2 ∞(T − t) < ∞,

where At∞ is the sup norm of the second fundamental form of L(t).

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Lemma (basins of attraction)

Let Lq be a singular leaf. Then there exists an ǫ = ǫ(Lq) such that if L(t0) lies in Tubǫ(Lq) we have: (a) For any t > t0 the distance r(t) = dist(L(t), Lq) satisfies C 2

1 (t − t0) ≤ r2(t0) − r2(t) ≤ C 2 2 (t − t0)

where C1 and C2 are positive constants that depend only

  • n Tubǫ(Lq).
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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Lemma (basins of attraction)

Let Lq be a singular leaf. Then there exists an ǫ = ǫ(Lq) such that if L(t0) lies in Tubǫ(Lq) we have: (a) For any t > t0 the distance r(t) = dist(L(t), Lq) satisfies C 2

1 (t − t0) ≤ r2(t0) − r2(t) ≤ C 2 2 (t − t0)

where C1 and C2 are positive constants that depend only

  • n Tubǫ(Lq).

(b) T < ∞ and L(t) ⊂ Tubǫ(Lq) for all t ∈ (t0, T).

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Lemma (basins of attraction)

Let Lq be a singular leaf. Then there exists an ǫ = ǫ(Lq) such that if L(t0) lies in Tubǫ(Lq) we have: (a) For any t > t0 the distance r(t) = dist(L(t), Lq) satisfies C 2

1 (t − t0) ≤ r2(t0) − r2(t) ≤ C 2 2 (t − t0)

where C1 and C2 are positive constants that depend only

  • n Tubǫ(Lq).

(b) T < ∞ and L(t) ⊂ Tubǫ(Lq) for all t ∈ (t0, T). (c) If L(t) converges to Lq at time T then for any t ∈ (t0, T], C1 √ T − t ≤ r(t) ≤ C2 √ T − t.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof of lemma (1) r′(t) = ∇r, ϕ′

t(p) = ∇r,

H(t) = tr(A∇r)

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof of lemma (1) r′(t) = ∇r, ϕ′

t(p) = ∇r,

H(t) = tr(A∇r) (2) −

˜ C2 r − c ≤ trA∇r ≤ − ˜ C1 r + c., from lemma semi-local

model.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof of lemma (1) r′(t) = ∇r, ϕ′

t(p) = ∇r,

H(t) = tr(A∇r) (2) −

˜ C2 r − c ≤ trA∇r ≤ − ˜ C1 r + c., from lemma semi-local

model. Set C 2

1

2 := ˜

C1 − ǫc and C 2

2

2 := ˜

C2 + ǫc

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof of lemma (1) r′(t) = ∇r, ϕ′

t(p) = ∇r,

H(t) = tr(A∇r) (2) −

˜ C2 r − c ≤ trA∇r ≤ − ˜ C1 r + c., from lemma semi-local

model. Set C 2

1

2 := ˜

C1 − ǫc and C 2

2

2 := ˜

C2 + ǫc Eq. (1) and eq. (2) imply

  • − C 2

2

2r(t) ≤ r′(t) ≤ − C 2

1

2r(t)

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof of lemma (1) r′(t) = ∇r, ϕ′

t(p) = ∇r,

H(t) = tr(A∇r) (2) −

˜ C2 r − c ≤ trA∇r ≤ − ˜ C1 r + c., from lemma semi-local

model. Set C 2

1

2 := ˜

C1 − ǫc and C 2

2

2 := ˜

C2 + ǫc Eq. (1) and eq. (2) imply

  • − C 2

2

2r(t) ≤ r′(t) ≤ − C 2

1

2r(t)

  • −C 2

2 ≤ 2r(t)r′(t) ≤ −C 2 1

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof of lemma (1) r′(t) = ∇r, ϕ′

t(p) = ∇r,

H(t) = tr(A∇r) (2) −

˜ C2 r − c ≤ trA∇r ≤ − ˜ C1 r + c., from lemma semi-local

model. Set C 2

1

2 := ˜

C1 − ǫc and C 2

2

2 := ˜

C2 + ǫc Eq. (1) and eq. (2) imply

  • − C 2

2

2r(t) ≤ r′(t) ≤ − C 2

1

2r(t)

  • −C 2

2 ≤ 2r(t)r′(t) ≤ −C 2 1

  • C 2

1 (t − t0) ≤ r2(t0) − r2(t) ≤ C 2 2 (t − t0) Q.E.D

Proof of item (a) of Theorem A the fact that M/F is compact, T < ∞ and the lemma imply L(t) → LT Q.E.D

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Proposition (ACG19)

Let M be a compact Riemannian manifold and F be a generalized isoparametric foliation on M, with possible non-closed leaves. Assume that the MCF t → L(t) of a regular leaf L(0) as initial datum has T < ∞.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Proposition (ACG19)

Let M be a compact Riemannian manifold and F be a generalized isoparametric foliation on M, with possible non-closed leaves. Assume that the MCF t → L(t) of a regular leaf L(0) as initial datum has T < ∞. Then t → L(t) must converge to the closure of a singular leaf. In other words, π(L(t)) converges to a singular point of M/F, where π : M → M/F is the canonical projection.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Lemma Under bounded curvature conditions, if N ⊂ ∂Tubǫ(L) then − C

r(x) − c1 ≤ tr(A∇r) ≤ − C r(x) + c1, where dim N > dim L.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Lemma Under bounded curvature conditions, if N ⊂ ∂Tubǫ(L) then − C

r(x) − c1 ≤ tr(A∇r) ≤ − C r(x) + c1, where dim N > dim L.

Proposition (ACG19)

Let F be a SRF with closed leaves on a complete manifold (M, g). Assume that (a1) M has bounded sectional curvature; (a2) the shape operator along each leaf L ∈ F is bounded; (a3) M/F is compact.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Lemma Under bounded curvature conditions, if N ⊂ ∂Tubǫ(L) then − C

r(x) − c1 ≤ tr(A∇r) ≤ − C r(x) + c1, where dim N > dim L.

Proposition (ACG19)

Let F be a SRF with closed leaves on a complete manifold (M, g). Assume that (a1) M has bounded sectional curvature; (a2) the shape operator along each leaf L ∈ F is bounded; (a3) M/F is compact. (b1) N is a immersed sub.manifold in a regular leaf; (b2) dim N > dim singular leaves; (b3) MCF t → N(t) is a restriction of a F-basic flow; (b4) T < ∞.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Lemma Under bounded curvature conditions, if N ⊂ ∂Tubǫ(L) then − C

r(x) − c1 ≤ tr(A∇r) ≤ − C r(x) + c1, where dim N > dim L.

Proposition (ACG19)

Let F be a SRF with closed leaves on a complete manifold (M, g). Assume that (a1) M has bounded sectional curvature; (a2) the shape operator along each leaf L ∈ F is bounded; (a3) M/F is compact. (b1) N is a immersed sub.manifold in a regular leaf; (b2) dim N > dim singular leaves; (b3) MCF t → N(t) is a restriction of a F-basic flow; (b4) T < ∞. Then N(t) converges to a singular leaf L.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof: Type I convergence Let f 0(t) be the distance between Lx and its focal set with respect with g0. From Radeschi and Alexandrino (2015) f 0(t) ≥ C √ T − t. We also have that A0(t)0 =

1 f 0(t)

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof: Type I convergence Let f 0(t) be the distance between Lx and its focal set with respect with g0. From Radeschi and Alexandrino (2015) f 0(t) ≥ C √ T − t. We also have that A0(t)0 =

1 f 0(t)

(1) A0(t)0 √ T − t ≤ C (from the above discussion).

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof: Type I convergence Let f 0(t) be the distance between Lx and its focal set with respect with g0. From Radeschi and Alexandrino (2015) f 0(t) ≥ C √ T − t. We also have that A0(t)0 =

1 f 0(t)

(1) A0(t)0 √ T − t ≤ C (from the above discussion). (2) Ax(t) ≤ C1A0

x(t)0 + C3 (holds for x close to q)

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof: Type I convergence Let f 0(t) be the distance between Lx and its focal set with respect with g0. From Radeschi and Alexandrino (2015) f 0(t) ≥ C √ T − t. We also have that A0(t)0 =

1 f 0(t)

(1) A0(t)0 √ T − t ≤ C (from the above discussion). (2) Ax(t) ≤ C1A0

x(t)0 + C3 (holds for x close to q)

(3) H(t) ≤ C1A0(t)0 + C2 (from lemma semi-local model)

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof: Type I convergence Let f 0(t) be the distance between Lx and its focal set with respect with g0. From Radeschi and Alexandrino (2015) f 0(t) ≥ C √ T − t. We also have that A0(t)0 =

1 f 0(t)

(1) A0(t)0 √ T − t ≤ C (from the above discussion). (2) Ax(t) ≤ C1A0

x(t)0 + C3 (holds for x close to q)

(3) H(t) ≤ C1A0(t)0 + C2 (from lemma semi-local model) (4) H(t) √ T − t ≤ C4 (from (1) and (3))

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof: Type I convergence Let f 0(t) be the distance between Lx and its focal set with respect with g0. From Radeschi and Alexandrino (2015) f 0(t) ≥ C √ T − t. We also have that A0(t)0 =

1 f 0(t)

(1) A0(t)0 √ T − t ≤ C (from the above discussion). (2) Ax(t) ≤ C1A0

x(t)0 + C3 (holds for x close to q)

(3) H(t) ≤ C1A0(t)0 + C2 (from lemma semi-local model) (4) H(t) √ T − t ≤ C4 (from (1) and (3)) (5) Eq. (4) implies the convergence of MCF in a relative compact neighborhoods.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

Sketch of proof: Type I convergence Let f 0(t) be the distance between Lx and its focal set with respect with g0. From Radeschi and Alexandrino (2015) f 0(t) ≥ C √ T − t. We also have that A0(t)0 =

1 f 0(t)

(1) A0(t)0 √ T − t ≤ C (from the above discussion). (2) Ax(t) ≤ C1A0

x(t)0 + C3 (holds for x close to q)

(3) H(t) ≤ C1A0(t)0 + C2 (from lemma semi-local model) (4) H(t) √ T − t ≤ C4 (from (1) and (3)) (5) Eq. (4) implies the convergence of MCF in a relative compact neighborhoods. (1), (2), (5) imply: Ax(t) √ T − t ≤ C5 and hence type I convergence.

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On Mean curvature flow of Singular Riemannian foliations: Non compact cases Marcos M. Alexandrino (IME-USP) In honor of Professor Jürgen Berndt’s 60th birthday. Definitions ThmA Basins of attraction MCF of non-closed regular leaf Cylinder structure Type 1

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