Coucher de soleil no. 1 sphere, also called Poincaré dodecahedral space, is a particular example of a homology sphere. Being a spherical 3-manifold, it is the only homology 3-sphere, besides the 3-sphere itself, with a finite fundamental group. While it is not known the extent to which such discoveries influenced Metzinger's representation of the radiating sun in "Coucher de soleil no. 1", his interest and prowess in mathematics is well documented. Coucher de soleil no. 1 Coucher de soleil no. 1 (also called Landscape, Paysage, Landschap, or Sunset No. 1) is an oil painting created circa 1906 by the French artist and theorist Jean Metzinger
Coucher de soleil no. 1 63.8 cm with a similar radiating sun above the bathers. (2) The brushstrokes are smaller in size consistent with Metzinger's style of late 1905. (3) In 1906 and 1907 Metzinger's brushstrokes became larger and more organized, structured within a highly geometrized framework already proto-Cubist in appearance. (4) As its name implies, "Coucher de soleil no. 1" might have been the first in a series of sunsets. Though no other works by Metzinger are known by the titles "Coucher de soleil no. 2" or "No. 3", the artist did produce other works with sunsets during the same period: "Landscape with Fountain",