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Volume of a geodesic ball in $\mathrm$\operatorname{SL}(n) / \mathrm{\operatorname{SO}(n)}$?

$\DeclareMathOperator\SL{SL}\DeclareMathOperator\SO{SO}$Crossposted on MSE: https://math.stackexchange.com/questions/4261809/volume-of-a-geodesic-ball-in-sln-son

Question: What is the volume of a geodesic ball of radius $r$ in the symmetric space $\SL(n) / \SO(n)$$\SL(n) / {\SO(n)}$?

Context: Let $M = \SL(n) / \SO(n)$$M = \SL(n) / {\SO(n)}$. We can view $M$ as the Riemannian manifold of real $n\times n$ positive definite matrices with determinant 1 endowed with the so-called affine-invariant metric: $$g_P(U, V) = \mathrm{trace}(P^{-1} U P^{-1} V)$$$$g_P(U, V) = \operatorname{trace}(P^{-1} U P^{-1} V)$$ for $P \in M$ and $U, V \in \mathrm{Sym}(n)$$U, V \in \operatorname{Sym}(n)$ (symmetric $n \times n$ matrices).


Attempts/what I know:

(1) Theorem 2.4 of Theorem 2.4Gual-Arnau and Naveira - Volume of this papertubes in noncompact symmetric spaces (screenshot attached) provides a formula for the volume of a geodesic ball for any noncompact symmetric space. However, I am not very familiar with symmetric space theory, so I am unable to parse what this formula says for $\SL(n) / \SO(n)$$\SL(n) / {\SO(n)}$. Example 3.4.6 of the lecture notes Example 3.4.6 of these lecture notesSymmetric spaces (Frühlingssemester 2018) give a formula for the roots $\alpha_j$ used in Theorem 2.4, and it is well-known the rank is $q = n-1$. However, I do not understand how to determine the constant $c$. I have an idea what the domain $C_0$ might be (the intersection of a sphere and a Weyl chamber--expressionschamber—expressions for the Weyl chambers can be found), but I am not confident if this is correct.

(2) When $n=2$, we know $\SL(n) / \SO(n)$$\SL(n) / {\SO(n)}$ is isometric to the hyperbolic plane of curvature $-1/2$. However, I am looking for a formula for general $n$.

(3) It is well-known that $\SL(n) / \SO(n)$$\SL(n) / {\SO(n)}$ contains a totally geodesic submanifold isometric to a hyperbolic space. This gives us a lower bound on the volume of a ball. However, this is not sufficient for my purposes.

(4) $\SL(n) / \SO(n)$$\SL(n) / {\SO(n)}$ has constant Ricci curvature, so we can use the Bishop-GromovBishop–Gromov inequality to get an upper bound on the volume. However, this is not sufficient for my purposes.

enter image description hereTheorem 2.4 from Gual-Arnau and Naveira article

Volume of a geodesic ball in $\mathrm{SL}(n) / \mathrm{SO}(n)$?

$\DeclareMathOperator\SL{SL}\DeclareMathOperator\SO{SO}$Crossposted on MSE: https://math.stackexchange.com/questions/4261809/volume-of-a-geodesic-ball-in-sln-son

Question: What is the volume of a geodesic ball of radius $r$ in the symmetric space $\SL(n) / \SO(n)$?

Context: Let $M = \SL(n) / \SO(n)$. We can view $M$ as the Riemannian manifold of real $n\times n$ positive definite matrices with determinant 1 endowed with the so-called affine-invariant metric: $$g_P(U, V) = \mathrm{trace}(P^{-1} U P^{-1} V)$$ for $P \in M$ and $U, V \in \mathrm{Sym}(n)$ (symmetric $n \times n$ matrices).


Attempts/what I know:

(1) Theorem 2.4 of this paper (screenshot attached) provides a formula for the volume of a geodesic ball for any noncompact symmetric space. However, I am not very familiar with symmetric space theory, so I am unable to parse what this formula says for $\SL(n) / \SO(n)$. Example 3.4.6 of these lecture notes give a formula for the roots $\alpha_j$ used in Theorem 2.4, and it is well-known the rank is $q = n-1$. However, I do not understand how to determine the constant $c$. I have an idea what the domain $C_0$ might be (the intersection of a sphere and a Weyl chamber--expressions for the Weyl chambers can be found), but I am not confident if this is correct.

(2) When $n=2$, we know $\SL(n) / \SO(n)$ is isometric to the hyperbolic plane of curvature $-1/2$. However, I am looking for a formula for general $n$.

(3) It is well-known that $\SL(n) / \SO(n)$ contains a totally geodesic submanifold isometric to a hyperbolic space. This gives us a lower bound on the volume of a ball. However, this is not sufficient for my purposes.

(4) $\SL(n) / \SO(n)$ has constant Ricci curvature, so we can the Bishop-Gromov inequality to get an upper bound on the volume. However, this is not sufficient for my purposes.

enter image description here

Volume of a geodesic ball in $\operatorname{SL}(n) / {\operatorname{SO}(n)}$?

$\DeclareMathOperator\SL{SL}\DeclareMathOperator\SO{SO}$Crossposted on MSE: https://math.stackexchange.com/questions/4261809/volume-of-a-geodesic-ball-in-sln-son

Question: What is the volume of a geodesic ball of radius $r$ in the symmetric space $\SL(n) / {\SO(n)}$?

Context: Let $M = \SL(n) / {\SO(n)}$. We can view $M$ as the Riemannian manifold of real $n\times n$ positive definite matrices with determinant 1 endowed with the so-called affine-invariant metric: $$g_P(U, V) = \operatorname{trace}(P^{-1} U P^{-1} V)$$ for $P \in M$ and $U, V \in \operatorname{Sym}(n)$ (symmetric $n \times n$ matrices).


Attempts/what I know:

(1) Theorem 2.4 of Gual-Arnau and Naveira - Volume of tubes in noncompact symmetric spaces (screenshot attached) provides a formula for the volume of a geodesic ball for any noncompact symmetric space. However, I am not very familiar with symmetric space theory, so I am unable to parse what this formula says for $\SL(n) / {\SO(n)}$. Example 3.4.6 of the lecture notes Symmetric spaces (Frühlingssemester 2018) give a formula for the roots $\alpha_j$ used in Theorem 2.4, and it is well-known the rank is $q = n-1$. However, I do not understand how to determine the constant $c$. I have an idea what the domain $C_0$ might be (the intersection of a sphere and a Weyl chamber—expressions for the Weyl chambers can be found), but I am not confident if this is correct.

(2) When $n=2$, we know $\SL(n) / {\SO(n)}$ is isometric to the hyperbolic plane of curvature $-1/2$. However, I am looking for a formula for general $n$.

(3) It is well-known that $\SL(n) / {\SO(n)}$ contains a totally geodesic submanifold isometric to a hyperbolic space. This gives us a lower bound on the volume of a ball. However, this is not sufficient for my purposes.

(4) $\SL(n) / {\SO(n)}$ has constant Ricci curvature, so we can use the Bishop–Gromov inequality to get an upper bound on the volume. However, this is not sufficient for my purposes.

Theorem 2.4 from Gual-Arnau and Naveira article

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Volume of a geodesic ball in $SL$\mathrm{SL}(n) / SO\mathrm{SO}(n)$?

Crossposted$\DeclareMathOperator\SL{SL}\DeclareMathOperator\SO{SO}$Crossposted on MSE: https://math.stackexchange.com/questions/4261809/volume-of-a-geodesic-ball-in-sln-son

Question: What is the volume of a geodesic ball of radius $r$ in the symmetric space $SL(n) / SO(n)$$\SL(n) / \SO(n)$?

Context: Let $M = SL(n) / SO(n)$$M = \SL(n) / \SO(n)$. We can view $M$ as the Riemannian manifold of real $n\times n$ positive definite matrices with determinant 1 endowed with the so-called affine-invariant metric: $$g_P(U, V) = \mathrm{trace}(P^{-1} U P^{-1} V)$$ for $P \in M$ and $U, V \in \mathrm{Sym}(n)$ (symmetric $n \times n$ matrices).


Attempts/what I know:

(1) Theorem 2.4 of this paper (screenshot attached) provides a formula for the volume of a geodesic ball for any noncompact symmetric space. However, I am not very familiar with symmetric space theory, so I am unable to parse what this formula says for $SL(n) / SO(n)$$\SL(n) / \SO(n)$. Example 3.4.6 of these lecture notes give a formula for the roots $\alpha_j$ used in Theorem 2.4, and it is well-known the rank is $q = n-1$. However, I do not understand how to determine the constant $c$. I have an idea what the domain $C_0$ might be (the intersection of a sphere and a Weyl chamber--expressions for the Weyl chambers can be found), but I am not confident if this is correct.

(2) When $n=2$, we know $SL(n) / SO(n)$$\SL(n) / \SO(n)$ is isometric to the hyperbolic plane of curvature $-1/2$. However, I am looking for a formula for general $n$.

(3) It is well-known that $SL(n) / SO(n)$$\SL(n) / \SO(n)$ contains a totally geodesic submanifold isometric to a hyperbolic space. This gives us a lower bound on the volume of a ball. However, this is not sufficient for my purposes.

(4) $SL(n) / SO(n)$$\SL(n) / \SO(n)$ has constant Ricci curvature, so we can the Bishop-Gromov inequality to get an upper bound on the volume. However, this is not sufficient for my purposes.

enter image description here

Volume of a geodesic ball in $SL(n) / SO(n)$?

Crossposted on MSE: https://math.stackexchange.com/questions/4261809/volume-of-a-geodesic-ball-in-sln-son

Question: What is the volume of a geodesic ball of radius $r$ in the symmetric space $SL(n) / SO(n)$?

Context: Let $M = SL(n) / SO(n)$. We can view $M$ as the Riemannian manifold of real $n\times n$ positive definite matrices with determinant 1 endowed with the so-called affine-invariant metric: $$g_P(U, V) = \mathrm{trace}(P^{-1} U P^{-1} V)$$ for $P \in M$ and $U, V \in \mathrm{Sym}(n)$ (symmetric $n \times n$ matrices).


Attempts/what I know:

(1) Theorem 2.4 of this paper (screenshot attached) provides a formula for the volume of a geodesic ball for any noncompact symmetric space. However, I am not very familiar with symmetric space theory, so I am unable to parse what this formula says for $SL(n) / SO(n)$. Example 3.4.6 of these lecture notes give a formula for the roots $\alpha_j$ used in Theorem 2.4, and it is well-known the rank is $q = n-1$. However, I do not understand how to determine the constant $c$. I have an idea what the domain $C_0$ might be (the intersection of a sphere and a Weyl chamber--expressions for the Weyl chambers can be found), but I am not confident if this is correct.

(2) When $n=2$, we know $SL(n) / SO(n)$ is isometric to the hyperbolic plane of curvature $-1/2$. However, I am looking for a formula for general $n$.

(3) It is well-known that $SL(n) / SO(n)$ contains a totally geodesic submanifold isometric to a hyperbolic space. This gives us a lower bound on the volume of a ball. However, this is not sufficient for my purposes.

(4) $SL(n) / SO(n)$ has constant Ricci curvature, so we can the Bishop-Gromov inequality to get an upper bound on the volume. However, this is not sufficient for my purposes.

enter image description here

Volume of a geodesic ball in $\mathrm{SL}(n) / \mathrm{SO}(n)$?

$\DeclareMathOperator\SL{SL}\DeclareMathOperator\SO{SO}$Crossposted on MSE: https://math.stackexchange.com/questions/4261809/volume-of-a-geodesic-ball-in-sln-son

Question: What is the volume of a geodesic ball of radius $r$ in the symmetric space $\SL(n) / \SO(n)$?

Context: Let $M = \SL(n) / \SO(n)$. We can view $M$ as the Riemannian manifold of real $n\times n$ positive definite matrices with determinant 1 endowed with the so-called affine-invariant metric: $$g_P(U, V) = \mathrm{trace}(P^{-1} U P^{-1} V)$$ for $P \in M$ and $U, V \in \mathrm{Sym}(n)$ (symmetric $n \times n$ matrices).


Attempts/what I know:

(1) Theorem 2.4 of this paper (screenshot attached) provides a formula for the volume of a geodesic ball for any noncompact symmetric space. However, I am not very familiar with symmetric space theory, so I am unable to parse what this formula says for $\SL(n) / \SO(n)$. Example 3.4.6 of these lecture notes give a formula for the roots $\alpha_j$ used in Theorem 2.4, and it is well-known the rank is $q = n-1$. However, I do not understand how to determine the constant $c$. I have an idea what the domain $C_0$ might be (the intersection of a sphere and a Weyl chamber--expressions for the Weyl chambers can be found), but I am not confident if this is correct.

(2) When $n=2$, we know $\SL(n) / \SO(n)$ is isometric to the hyperbolic plane of curvature $-1/2$. However, I am looking for a formula for general $n$.

(3) It is well-known that $\SL(n) / \SO(n)$ contains a totally geodesic submanifold isometric to a hyperbolic space. This gives us a lower bound on the volume of a ball. However, this is not sufficient for my purposes.

(4) $\SL(n) / \SO(n)$ has constant Ricci curvature, so we can the Bishop-Gromov inequality to get an upper bound on the volume. However, this is not sufficient for my purposes.

enter image description here

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Crossposted on MSE: https://math.stackexchange.com/questions/4261809/volume-of-a-geodesic-ball-in-sln-son

Question: What is the volume of a geodesic ball of radius $r$ in the symmetric space $SL(n) / SO(n)$?

Context: Let $M = SL(n) / SO(n)$. We can view $M$ as the Riemannian manifold of real $n\times n$ positive definite matrices with determinant 1 endowed with the so-called affine-invariant metric: $$g_P(U, V) = \mathrm{trace}(P^{-1} U P^{-1} V)$$ for $P \in M$ and $U, V \in \mathrm{Sym}(n)$ (symmetric $n \times n$ matrices).


Attempts/what I know:

(1) Theorem 2.4 of this paper (screenshot attached) provides a formula for the volume of a geodesic ball for any noncompact symmetric space. However, I am not very familiar with symmetric space theory, so I am unable to parse what this formula says for $SL(n) / SO(n)$. Example 3.4.6 of these lecture notes give a formula for the roots $\alpha_j$ used in Theorem 2.4, and it is well-known the rank is $q = n-1$. However, I do not understand how to determine the constant $c$. I have an idea what the domain $C_0$ might be (the intersection of a sphere and a Weyl chamber--expressions for the Weyl chambers can be found), but I am not confident if this is correct.

(2) When $n=2$, we know $SL(n) / SO(n)$ is isometric to the hyperbolic plane of curvature $-1/2$. However, I am looking for a formula for general $n$.

(3) It is well-known that $SL(n) / SO(n)$ contains a totally geodesic submanifold isometric to a hyperbolic space. This gives us a lower bound on the volume of a ball. However, this is not sufficient for my purposes.

(4) $SL(n) / SO(n)$ has constant Ricci curvature, so we can the Bishop-Gromov inequality to get an upper bound on the volume. However, this is not sufficient for my purposes.

enter image description here

Question: What is the volume of a geodesic ball of radius $r$ in the symmetric space $SL(n) / SO(n)$?

Context: Let $M = SL(n) / SO(n)$. We can view $M$ as the Riemannian manifold of real $n\times n$ positive definite matrices with determinant 1 endowed with the so-called affine-invariant metric: $$g_P(U, V) = \mathrm{trace}(P^{-1} U P^{-1} V)$$ for $P \in M$ and $U, V \in \mathrm{Sym}(n)$ (symmetric $n \times n$ matrices).


Attempts/what I know:

(1) Theorem 2.4 of this paper (screenshot attached) provides a formula for the volume of a geodesic ball for any noncompact symmetric space. However, I am not very familiar with symmetric space theory, so I am unable to parse what this formula says for $SL(n) / SO(n)$. Example 3.4.6 of these lecture notes give a formula for the roots $\alpha_j$ used in Theorem 2.4, and it is well-known the rank is $q = n-1$. However, I do not understand how to determine the constant $c$. I have an idea what the domain $C_0$ might be (the intersection of a sphere and a Weyl chamber--expressions for the Weyl chambers can be found), but I am not confident if this is correct.

(2) When $n=2$, we know $SL(n) / SO(n)$ is isometric to the hyperbolic plane of curvature $-1/2$. However, I am looking for a formula for general $n$.

(3) It is well-known that $SL(n) / SO(n)$ contains a totally geodesic submanifold isometric to a hyperbolic space. This gives us a lower bound on the volume of a ball. However, this is not sufficient for my purposes.

(4) $SL(n) / SO(n)$ has constant Ricci curvature, so we can the Bishop-Gromov inequality to get an upper bound on the volume. However, this is not sufficient for my purposes.

enter image description here

Crossposted on MSE: https://math.stackexchange.com/questions/4261809/volume-of-a-geodesic-ball-in-sln-son

Question: What is the volume of a geodesic ball of radius $r$ in the symmetric space $SL(n) / SO(n)$?

Context: Let $M = SL(n) / SO(n)$. We can view $M$ as the Riemannian manifold of real $n\times n$ positive definite matrices with determinant 1 endowed with the so-called affine-invariant metric: $$g_P(U, V) = \mathrm{trace}(P^{-1} U P^{-1} V)$$ for $P \in M$ and $U, V \in \mathrm{Sym}(n)$ (symmetric $n \times n$ matrices).


Attempts/what I know:

(1) Theorem 2.4 of this paper (screenshot attached) provides a formula for the volume of a geodesic ball for any noncompact symmetric space. However, I am not very familiar with symmetric space theory, so I am unable to parse what this formula says for $SL(n) / SO(n)$. Example 3.4.6 of these lecture notes give a formula for the roots $\alpha_j$ used in Theorem 2.4, and it is well-known the rank is $q = n-1$. However, I do not understand how to determine the constant $c$. I have an idea what the domain $C_0$ might be (the intersection of a sphere and a Weyl chamber--expressions for the Weyl chambers can be found), but I am not confident if this is correct.

(2) When $n=2$, we know $SL(n) / SO(n)$ is isometric to the hyperbolic plane of curvature $-1/2$. However, I am looking for a formula for general $n$.

(3) It is well-known that $SL(n) / SO(n)$ contains a totally geodesic submanifold isometric to a hyperbolic space. This gives us a lower bound on the volume of a ball. However, this is not sufficient for my purposes.

(4) $SL(n) / SO(n)$ has constant Ricci curvature, so we can the Bishop-Gromov inequality to get an upper bound on the volume. However, this is not sufficient for my purposes.

enter image description here

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