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The research team developed a new approach to classifying these hundreds of millions of galaxies. Instead of relying on crowdsourced classification, the researchers used knowledge from the state-of-the-art Xception neural network, combined with the datasets generated by the Galaxy Zoo project, to train its deep learning models. They then applied the trained model to galactic images from the Dark Energy Survey (DES) – where it achieved a 99.6% accuracy in identifying spiral and elliptical galaxies.

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If, in the field of art, dismantling symmetry is a deliberate act that provokes fascination and astonishment, how should we explain the fact that nature seems distinctly inclined to resist succumbing to the same process?

The universe that emerges after the phase of inflation is in a state of perfection. The laws of physics that regulate it are marvellously symmetrical. Why does such a perfect mechanism shatter?

To understand the role for physics of spontaneous symmetry breaking, we can resort to a mechanical example: a pencil resting on its point on a flat surface. The initial state of the system is perfectly symmetrical. The pencil can rotate on its axis and the laws of physics are the same, because the gravitational field is symmetrical for those rotations around the vertical axis. In other words when the pencil falls flat to the surface, it will do so in any direction. The symmetrical state is unstable, and left alone the pencil will fall. On the horizontal plane the pencil is stable, but it has broken the rotational symmetry of the gravitational field because it has opted for a particular direction. Falling on the flat surface the pencil may have lost energy and symmetry, but it has gained stability and multiplicity.

Something of this kind occurred in the early universe. The initial incandescent state had a high level of symmetry, but it was unstable; as it cools down it loses symmetry but acquires stability.

But what was the state of lower energy into which this universe was placed? What mechanism could cause the electroweak symmetry to spontaneously rupture?