Expanding or Contracting?
Einstein's theory of General Relativity predicts that the
Universe cannot be static — it must be expanding or
contracting. Einstein adds the "Cosmological Constant" to keep
the Universe static.
In Their Own Words
Snippets of papers published by other astronomers during this
time. The snippets here highlight the Cepheid period-luminosity
relationship, redshift of galaxies, and the nature of spiral
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