# Eli5:In non-euclidean geometry (for my example a globe).Lines of longitude are parallel @ the equator but meet @ the poles. Lines of latitude (let’s take tropic cancer, equator & tropic Capricorn)also 3 lines are parallel, also on a curved plain, but this time don’t converge.What am I missing out?

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Eli5:In non-euclidean geometry (for my example a globe).Lines of longitude are parallel @ the equator but meet @ the poles. Lines of latitude (let’s take tropic cancer, equator & tropic Capricorn)also 3 lines are parallel, also on a curved plain, but this time don’t converge.What am I missing out?

In: Mathematics

Lines of longitude are all exactly equal in length and are “great circles” – the longest possible line you can draw on a sphere. Every great circle will intersect every other great circle in two places. The only line of latitude that is a great circle is the equator. All other longitudinal lines are shorter. You can have an infinite number of non-intersecting circles on a sqare, provided you have at most one great circle.

The lines of longitude are all circles of the same size, rotated slightly so they only cross at the poles. They are only parallel at the equator because at all other points they are getting closer as they converge.

The lines of latitude are concentric circles; different sizes next to one another. That means they don’t overlap.