Shaping our Understanding of the Universe: Flat or Spherical?

A new paper published in Nature Astrology has bewildered cosmologists by concluding that the shape of the universe might be a sphere, sparking a ‘cosmological crisis’ and forcing scientists to rethink their understanding of the universe. This data was collected by the European Space Agency’s Planck satellite between 2009 and 2013 and new analysis show they may be evidence that the universe is a closed sphere. Up until now, cosmological models have been based on the assumption that the universe is flat like a sheet of paper. Most existing data has supported this, including preliminary analysis of this Planck satellite data.

The Planck satellite observed the motion of the cosmic microwave background radiation (CMB) – light that was produced at the time of the Big Bang and which now floats through space, faintly illuminating it. The satellite measured the amount of gravitational lensing (bending of the light due to the gravitational pull of other celestial bodies) that the light had undergone during its journey through the universe to the satellite. A higher degree of lensing than expected suggested to the team of researchers that the universe is denser than previously thought. There is a critical level of density of the universe that, if reached, would cause the universe to close in on itself, forming a sphere. The density found by the authors of the article exceeded this critical value, leading them to declare a ‘cosmological crisis’.

The authors of the papers themselves have commented on the need to interpret the data with caution, however. They point out that the amount of evidence pointing to a flat universe far exceeds the evidence for a spherical one. One major anomaly is that the Planck data set predicts a different Hubble constant (the rate of the expansion of the universe) to the value that was calculated using data from the Hubble telescope in 2018. Other scientists in the field have attributed the findings of the paper to a ‘statistical fluke’ rather than hastily subscribing to the radical view that the Universe is closed. 

One of the authors explained that the aim is not to conclude that the Universe is a sphere, but to highlight that our understanding of the shape of the Universe is incomplete. The inconsistencies in the data demonstrate that there must be a missing aspect or error in at least one of the models which would account for such discrepancies. Further research and analysis is needed to gain a fuller picture of the Universe and to understand why scientists are finding symptoms of both a flat and a spherical universe.

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