\[
\newcommand{\C}{\mathbb{C}}
\newcommand{\haar}{\mathsf{m}}
\newcommand{\P}{\mathcal{P}}
\newcommand{\R}{\mathbb{R}}
\newcommand{\N}{\mathbb{N}}
\newcommand{\Z}{\mathbb{Z}}
\newcommand{\d}{\mathsf{d}}
\newcommand{\g}{>}
\newcommand{\l}{<}
\newcommand{\intd}{\,\mathsf{d}}
\newcommand{\Re}{\mathsf{Re}}
\newcommand{\area}{\mathop{\mathsf{Area}}}
\newcommand{\met}{\mathop{\mathsf{d}}}
\newcommand{\emptyset}{\varnothing}
\newcommand{\B}{\mathscr{B}}
\newcommand{\fou}{\mathcal{F}}
\]
Fix an irrational number $\alpha$ and put
\[
T(x) = x + \alpha \bmod 1
\]
for all $x \in [0,1)$.
- Is there $n \in \N$ with $0 \l T^n(0) \l \tfrac{1}{4}$?
- Is there $n \in 2\N$ with $0 \l T^n(0) \l \tfrac{1}{4}$?
- Is there $n \in 2\N+1$ with $0 \l T^n(0) \l \tfrac{1}{4}$?
- Is there $0 \le n \le 3$ with $0 \l T^n(0) \l \tfrac{1}{4}$?
- Is there $0 \le n \le 7^{1000}$ with $0 \l T^n(0) \l \tfrac{1}{4}$?
- Is there $0 \le n \le 3$ with $-\tfrac{1}{8} \l T^n(0) \l \tfrac{1}{8}$?
- Is there $0 \le n \le 7^{1000}$ with $-\tfrac{1}{8} \l T^n(0) \l \tfrac{1}{8}$?