3 ms·
Another view of topology is in John L.\ Kelley, {\it General Topology,\/} D.\ Van Nostrand, Princeton, 1955.\ \ In the set R of the real numbers and x, y in R
by graycat 2y ago
Another view of topology is in
John L.\ Kelley,
{\it General Topology,\/}
D.\ Van Nostrand,
Princeton,
1955.\ \
In the set R of the real numbers
and x, y in R with x < y,
(x,y) = { z | x < z < y }
is open and, with x <= y,
[x,y] = { z | x <= z <= y }
is closed.
A subset of R that is both closed and
bounded is compact, a powerful property, e.g., in Riemann integration.
And so forth but
in topological spaces much
more general than the real line
and open and closed intervals.
Apparently hence
the "General" in the book.
As a math major senior in college,
read Kelley and gave lectures
to a prof. But now there are
some other definitions of topology.