Polish Spaces
Descriptive set theory begins with the study of Polish spaces and their Borel sets.
A Polish space is a second countable topological space that is metrizable with a complete metric. Equivalently, it is a complete separable metric space whose metric has been "forgotten". Examples include the real line, the Baire space, the Cantor space, and the Hilbert cube .
Read more about this topic: Descriptive Set Theory
Famous quotes containing the words polish and/or spaces:
“Use the stones of another hill to polish your own jade.”
—Chinese proverb.
“We should read history as little critically as we consider the landscape, and be more interested by the atmospheric tints and various lights and shades which the intervening spaces create than by its groundwork and composition.”
—Henry David Thoreau (1817–1862)