Finite or Infinite Space

UNSOLVED CLASSICAL PROBLEMS A. Finite or Infinite Space 

Since the discovery of quasars by Maarten Schmidt at the Palomar Observatory in 1963, cosmologists have hoped that these most distant observed objects could be used to extend the Hubble relationship to the nonlinear regime and decide the sign of the curvature. Quasars are now known with spectral features up to 6.0 times their terrestrial wavelengths, corresponding to Doppler recession 

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