The ‘Paradox of Youth’

The ‘Paradox of Youth’ were young stars dominate the Galaxy Centre is associated with the formation of stars and not with the Standard Model. This model suggests stars condense from clouds of material across the Galactic Plane and fall into the Galaxy Centre, or Bulge, over time. That makes it full of old stars but, demonstrated by the image of a galaxy were white indicates hot new stars, the Bulge is full of young.

This paradox is explained by matter arriving around the Central Object, creating a star forming region called the Torus, that condense into stars which spiral across the Galaxy over time. This is were most stars are formed and create a growth process. That predicts an ageing system as the further across the Galaxy the older the stars (except those formed in clusters etc - and the possible condensing from clouds in the inter-star medium). So unstable and short lived stars don’t get far and only found in, or close to, the Bulge.

Clusters and Nebula also tend to follow this pattern of ageing over the Galactic Plane and may be part of the same conveyance.(M. Arnaud. ‘The Evolution of Galaxy Clusters Across Cosmic Time’ 2010)