History of the Atom Project Extension

By marapfaria
  • 460 BCE

    Democritus

    Democritus
    was a central figure in the development of the atomic theory of the universe. He theorized that all material bodies are made up of indivisibly small “atoms.” Aristotle famously rejected atomism in On Generation and Corruption.

  • J. J. Thomson

    J. J. Thomson
    Thomson's experiments with cathode-ray tubes showed that all atoms contain tiny negatively charged subatomic particles or electrons. Thomson proposed the plum pudding model of the atom, which had negatively-charged electrons embedded within a positively-charged "soup."

  • marie curie

    marie curie
    she deduced that radioactivity does not depend on how atoms are arranged into molecules, but rather that it originates within the atoms themselves. This discovery is perhaps her most important scientific contribution.