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paracompactness
Directory
References
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
Normandy Invasion: Omaha Beach. World War II. D-Day. Infographic. SPOTLIGHT VERSION
Facts and Figures About the Landings on Omaha Beach During the Normandy Invasion on June 6, 1944
An ancient egyptian hieroglyphic painted carving showing the falcon headed god Horus seated on a throne and holding a golden fly whisk. Before him are the Pharoah Seti and the goddess Isis. Interior wall of the temple to Osiris at Abydos, Egypt.
11 Egyptian Gods and Goddesses
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)
Statue of Nostradamus
Nostradamus and His Prophecies
airplane in flight (plane, aircraft, flying)
7 Puzzling Plane Disappearances
New York NY/ USA- November 23, 2018 Hordes of shoppers throng the Macy's Herald Square flagship store in New York looking for bargains on the day after Thanksgiving, Black Friday.
Why Is It Called Black Friday?

paracompactness

mathematics

Learn about this topic in these articles:

history of topology

  • Because both a doughnut and a coffee cup have one hole (handle), they can be mathematically, or topologically, transformed into one another without cutting them in any way. For this reason, it has often been joked that topologists cannot tell the difference between a coffee cup and a doughnut.
    In topology: History of topology

    …work on the notion of paracompactness, a property that generalizes compactness.

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