manifold

Table of Contents

Introduction References & Edit History Related Topics

Discover

Lake Mead (the impounded Colorado River) at the Hoover Dam. The light-coloured band of rock above the shoreline shows the decrease in water level in the first few years of the 21st century.

6 Lakes That Are Drying Up

Nelson Mandela, undated photo.

15 Nelson Mandela Quotes

African Americans demonstrating for voting rights in front of the White House as police and others watch, March 12, 1965. One sign reads, "We demand the right to vote everywhere." Voting Rights Act, civil rights.

Timeline of the American Civil Rights Movement

Demystified - Do Lemmings Really Commit Mass Suicide? illustration

Do Lemmings Really Commit Mass Suicide?

Statue of Nostradamus

Nostradamus and His Prophecies

Estimated battle casualties, Normandy invasion, World War II. WWII, D-Day

Estimated Battle Casualties During the Normandy Invasion and Campaign to Liberate Paris (June–August 1944)

Salem Witch Trials. Photogravure after the painting by Walter McEwen titled - The Witches - circa 1890s.

How Rye Bread May Have Caused the Salem Witch Trials

manifold: Related Content

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Topics

cobordism Poincaré conjecture Betti number curvature vector tangent vector h-cobordism theorem topological space metric space Hausdorff space homotopy homology compactness

Key People

Bernhard Riemann, lithograph after a portrait, artist unknown, 1863.

Bernhard Riemann

German mathematician

Grigori Perelman

Russian mathematician

Sergei Novikov

Russian mathematician

William Paul Thurston

American mathematician

Kodaira Kunihiko

Kodaira Kunihiko

Japanese mathematician

Curtis McMullen

American mathematician

Quiz

Equations written on blackboard

Numbers and Mathematics