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taylor
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Let $x\in \mathbb R$ be a badly approximable number. By Dani's correspondence, $g_t u_x \mathbb Z^2$ is bounded away from the cusp in $X=\text{SL}(2,\mathbb R)/\text{SL}(2,\mathbb Z)$, identified with the space of unimodular lattices in $\mathbb R^2$. Here $g_t=\text{diag}(e^t,e^{-t})$ and $u_x=\begin{bmatrix} 1 & x\\ 0 & 1 \end{bmatrix}$.

I wonder if it is true that there exists a closed orbit $Hx_0$ where $H$ is a subgroup of $\text{SL}(2,\mathbb R)$ and a $H$-invariant Borel probability measure such that

$$\lim_{t\to \infty} \frac{1}{T}\int_0^T f(g_t u_x \mathbb Z^2)dt =\int_{Hx_0} f(y)d\mu_{Hx_0}(y)$$

for any $f\in C_c(X)$, and how to prove or disprove it. I am aware of Ratner's theory on unipotent flows but this is different. Sorry for my ignorance but the literature on this side is more on diophantine approximation rather than closed orbit equidistribution. By ergodicity, we already know this equidistribution holds for generic base points on the whole space but this fact is not helpful for this particular case as geodesic orbits of badly approximable numbers are not dense anyway.

Let $x\in \mathbb R$ be a badly approximable number. By Dani's correspondence, $g_t u_x \mathbb Z^2$ is bounded away from the cusp in $X=\text{SL}(2,\mathbb R)/\text{SL}(2,\mathbb Z)$, identified with the space of unimodular lattices in $\mathbb R^2$. Here $g_t=\text{diag}(e^t,e^{-t})$ and $u_x=\begin{bmatrix} 1 & x\\ 0 & 1 \end{bmatrix}$.

I wonder if it is true that there exists a closed orbit $Hx_0$ where $H$ is a subgroup of $\text{SL}(2,\mathbb R)$ and a $H$-invariant Borel probability measure such that

$$\lim_{t\to \infty} \frac{1}{T}\int_0^T f(g_t u_x \mathbb Z^2)dt =\int_{Hx_0} f(y)d\mu_{Hx_0}(y)$$

for any $f\in C_c(X)$, and how to prove or disprove it. I am aware of Ratner's theory on unipotent flows but this is different. Sorry for my ignorance but the literature on this side is more on diophantine approximation rather than equidistribution. By ergodicity, we already know this equidistribution holds for generic base points on the whole space but this fact is not helpful for this particular case as geodesic orbits of badly approximable numbers are not dense anyway.

Let $x\in \mathbb R$ be a badly approximable number. By Dani's correspondence, $g_t u_x \mathbb Z^2$ is bounded away from the cusp in $X=\text{SL}(2,\mathbb R)/\text{SL}(2,\mathbb Z)$, identified with the space of unimodular lattices in $\mathbb R^2$. Here $g_t=\text{diag}(e^t,e^{-t})$ and $u_x=\begin{bmatrix} 1 & x\\ 0 & 1 \end{bmatrix}$.

I wonder if it is true that there exists a closed orbit $Hx_0$ where $H$ is a subgroup of $\text{SL}(2,\mathbb R)$ and a $H$-invariant Borel probability measure such that

$$\lim_{t\to \infty} \frac{1}{T}\int_0^T f(g_t u_x \mathbb Z^2)dt =\int_{Hx_0} f(y)d\mu_{Hx_0}(y)$$

for any $f\in C_c(X)$, and how to prove or disprove it. I am aware of Ratner's theory on unipotent flows but this is different. Sorry for my ignorance but the literature on this side is more on diophantine approximation rather than closed orbit equidistribution. By ergodicity, we already know this equidistribution holds for generic base points on the whole space but this fact is not helpful for this particular case as geodesic orbits of badly approximable numbers are not dense anyway.

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taylor
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How to show the geodesic orbitsorbit of a badly approximable numbersnumber are/are not homogeneously equidistributed on its orbit closure?

Let $x\in \mathbb R$ be a badly approximable number. By Dani's correspondence, $g_t u_x \mathbb Z^2$ is bounded away from the cusp in $X=\text{SL}(2,\mathbb R)/\text{SL}(2,\mathbb Z)$, identified with the space of unimodular lattices in $\mathbb R^2$. Here $g_t=\text{diag}(e^t,e^{-t})$ and $u_x=\begin{bmatrix} 1 & x\\ 0 & 1 \end{bmatrix}$.

I wonder if it is true that there exists a closed orbit $Hx_0$ where $H$ is a subgroup of $\text{SL}(2,\mathbb R)$ and a $H$-invariant Borel probability measure such that

$$\lim_{t\to \infty} \frac{1}{T}\int_0^T f(g_t u_x \mathbb Z^2)dt =\int_{Hx_0} f(y)d\mu_{Hx_0}(y)$$

for any $f\in C_c(X)$, and how to prove or disprove it. I am aware of Ratner's theory on unipotent flows but this is different. Sorry for my ignorance but the literature on this side is more on diophantine approximation rather than equidistribution. By ergodicity, we already know this equidistribution holds for generic base points on the whole space but this fact is not helpful for this particular case as geodesic orbits of badly approximable numbers are not dense anyway.

How to show the geodesic orbits of badly approximable numbers are/are not homogeneously equidistributed?

Let $x\in \mathbb R$ be a badly approximable number. By Dani's correspondence, $g_t u_x \mathbb Z^2$ is bounded away from the cusp in $X=\text{SL}(2,\mathbb R)/\text{SL}(2,\mathbb Z)$, identified with the space of unimodular lattices in $\mathbb R^2$. Here $g_t=\text{diag}(e^t,e^{-t})$ and $u_x=\begin{bmatrix} 1 & x\\ 0 & 1 \end{bmatrix}$.

I wonder if it is true that there exists a closed orbit $Hx_0$ where $H$ is a subgroup of $\text{SL}(2,\mathbb R)$ and a $H$-invariant Borel probability measure such that

$$\lim_{t\to \infty} \frac{1}{T}\int_0^T f(g_t u_x \mathbb Z^2)dt =\int_{Hx_0} f(y)d\mu_{Hx_0}(y)$$

for any $f\in C_c(X)$, and how to prove or disprove it. I am aware of Ratner's theory on unipotent flows but this is different. Sorry for my ignorance but the literature on this side is more on diophantine approximation rather than equidistribution. By ergodicity, we already know this equidistribution holds for generic base points.

How to show the geodesic orbit of a badly approximable number are/are not homogeneously equidistributed on its orbit closure?

Let $x\in \mathbb R$ be a badly approximable number. By Dani's correspondence, $g_t u_x \mathbb Z^2$ is bounded away from the cusp in $X=\text{SL}(2,\mathbb R)/\text{SL}(2,\mathbb Z)$, identified with the space of unimodular lattices in $\mathbb R^2$. Here $g_t=\text{diag}(e^t,e^{-t})$ and $u_x=\begin{bmatrix} 1 & x\\ 0 & 1 \end{bmatrix}$.

I wonder if it is true that there exists a closed orbit $Hx_0$ where $H$ is a subgroup of $\text{SL}(2,\mathbb R)$ and a $H$-invariant Borel probability measure such that

$$\lim_{t\to \infty} \frac{1}{T}\int_0^T f(g_t u_x \mathbb Z^2)dt =\int_{Hx_0} f(y)d\mu_{Hx_0}(y)$$

for any $f\in C_c(X)$, and how to prove or disprove it. I am aware of Ratner's theory on unipotent flows but this is different. Sorry for my ignorance but the literature on this side is more on diophantine approximation rather than equidistribution. By ergodicity, we already know this equidistribution holds for generic base points on the whole space but this fact is not helpful for this particular case as geodesic orbits of badly approximable numbers are not dense anyway.

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taylor
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Let $x\in \mathbb R$ be a badly approximable number. By Dani's correspondence, $g_t u_x \mathbb Z^2$ is bounded away from the cusp in $X=\text{SL}(2,\mathbb R)/\text{SL}(2,\mathbb Z)$, identified with the space of unimodular lattices in $\mathbb R^2$. Here $g_t=\text{diag}(e^t,e^{-t})$ and $u_x=\begin{bmatrix} 1 & x\\ 0 & 1 \end{bmatrix}$.

I wonder if it is true that there exists a closed orbit $Hx_0$ where $H$ is a subgroup of $\text{SL}(2,\mathbb R)$ and a $H$-invariant Borel probability measure such that

$$\lim_{t\to \infty} \frac{1}{T}\int_0^T f(g_t u_x \mathbb Z^2)dt =\int_{Hx_0} f(y)d\mu_{Hx_0}(y)$$

for any $f\in C_c(X)$, and how to prove or disprove it. I am aware of Ratner's theory on unipotent flows but this is different. Sorry for my ignorance but the literature on this side is more on diophantine approximation rather than equidistribution. By ergodicity, we already know this equidistribution holds for generic base points.

Let $x\in \mathbb R$ be a badly approximable number. By Dani's correspondence, $g_t u_x \mathbb Z^2$ is bounded away from the cusp in $X=\text{SL}(2,\mathbb R)/\text{SL}(2,\mathbb Z)$, identified with the space of unimodular lattices in $\mathbb R^2$. Here $g_t=\text{diag}(e^t,e^{-t})$ and $u_x=\begin{bmatrix} 1 & x\\ 0 & 1 \end{bmatrix}$.

I wonder if it is true that there exists a closed orbit $Hx_0$ where $H$ is a subgroup of $\text{SL}(2,\mathbb R)$ and a $H$-invariant Borel probability measure such that

$$\lim_{t\to \infty} \frac{1}{T}\int_0^T f(g_t u_x \mathbb Z^2)dt =\int_{Hx_0} f(y)d\mu_{Hx_0}(y)$$

for any $f\in C_c(X)$, and how to prove or disprove it. I am aware of Ratner's theory on unipotent flows but this is different. Sorry for my ignorance but the literature on this side is more on diophantine approximation rather than equidistribution.

Let $x\in \mathbb R$ be a badly approximable number. By Dani's correspondence, $g_t u_x \mathbb Z^2$ is bounded away from the cusp in $X=\text{SL}(2,\mathbb R)/\text{SL}(2,\mathbb Z)$, identified with the space of unimodular lattices in $\mathbb R^2$. Here $g_t=\text{diag}(e^t,e^{-t})$ and $u_x=\begin{bmatrix} 1 & x\\ 0 & 1 \end{bmatrix}$.

I wonder if it is true that there exists a closed orbit $Hx_0$ where $H$ is a subgroup of $\text{SL}(2,\mathbb R)$ and a $H$-invariant Borel probability measure such that

$$\lim_{t\to \infty} \frac{1}{T}\int_0^T f(g_t u_x \mathbb Z^2)dt =\int_{Hx_0} f(y)d\mu_{Hx_0}(y)$$

for any $f\in C_c(X)$, and how to prove or disprove it. I am aware of Ratner's theory on unipotent flows but this is different. Sorry for my ignorance but the literature on this side is more on diophantine approximation rather than equidistribution. By ergodicity, we already know this equidistribution holds for generic base points.

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taylor
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