Universe Not Silent Because No One There. Civilizations Stopped by Great Filter

Enrico Fermi Italian physicist helped build first US nuclear reactor. 1950, lunch with colleagues, mentioned alien possibility then asked: "Where are they?" Question later called Fermi paradox.

Enrico Fermi Italian physicist helped build first US nuclear reactor. 1950, lunch with colleagues, mentioned alien possibility then asked: "Where are they?" Question later called Fermi paradox.

Enrico Fermi Italian physicist helped build first US nuclear reactor. 1950, lunch with colleagues, mentioned alien possibility then asked: "Where are they?" Question later called Fermi paradox.

Enrico Fermi Italian physicist helped build first US nuclear reactor. 1950, lunch with colleagues, mentioned alien possibility then asked: "Where are they?" Question later called Fermi paradox.