OUR UNIVERSE’S MISSING LINK
Observation and theory make up the two pillars of scientific research. Without observations, there is just a theory with no substance, and without theory there is just a series of measurements with nothing to extrapolate from them. But what happens when one does not satisfy the other? Recent research about the expansion of the universe and the model that astronomers use to predict its history has caused tension between these two pillars. It appears as though recent measurements of galactic distances over a hundred million light years away and their respective recession speeds have contributed to a persistent discrepancy that keeps cropping up.
Measuring the distance to galaxies has been a relentless objective of astronomers since the beginning of the 20th century. Although many names can be attached to discovering the expansion of the universe – such as Vesto Slipher, Carl Wirtz, Knut Lundmark and Georges Lemaître – it was the work of an American astronomer called Edwin Hubble, the eponym of a law, a constant and a space telescope, who had the most profound effect on this area of research.
In the 1920s Hubble used a
