Dear Colleagues,

On behalf of the Advisory and Editorial Board members of Universe, it is a pleasure for me, as the journal’s Editor-in-Chief, to announce a Special Issue to celebrate Professor Roger Penrose, who serves on Universe’s Advisory Board, being jointly awarded the Nobel Prize in Physics 2020.

The possibility that peculiar regions in spacetime allow only for the inward motion of light and matter, which later gained notoriety as Black Holes (BHs), is one of the most exotic and, at the same time, disorienting fruits to have fallen from the branched tree of the Einsteinian General Theory of Relativity (GTR) soon after its birth. A gift that the latter’s father himself denied, convinced that there could be no realistic physical processes capable of actually creating such a bizarre spacetime configuration at the end of the gravitational collapse of any real astrophysical object. Decades later, Professor Penrose elucidated that, on the contrary, the GTR cannot avoid the formation of BHs even in physically realistic scenarios for the latter stages of the life of a sufficiently heavy star. Perhaps even more astounding and disturbing, the final act of the infalling matter after its crossing of the event horizon signals, at the BH’s center, the GTR reaching the boundaries of its validity. An unescapable spacetime singularity warns us that Einstein’s theory cannot be the last word about gravity, pointing toward the need for its marriage, to date not yet celebrated, with quantum mechanics.

A subtle red thread ideally connects such theoretical studies to the empirical investigations carried out in recent decades by the other laureates of the Nobel Prize in Physics 2020, Professor Genzel and Professor Ghez, that aimed to observationally corroborate the concept of BHs to which the results of Professor Penrose gave so firm theoretical support.

His fertile physical intuition, his multidisciplinary curiosity, and the elegance of his mathematical methods have also tirelessly led Professor Penrose on other roads at the intersection of different scientific domains. Our hope is that he will continue treading these paths, in the hope that he will discover new interesting ones.

In the footsteps of Professor Penrose, we invite all researchers in this field to contribute their valuable papers to this celebratory Special Issue of Universe.

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Key discoveries

Further reading

Prof. Dr. Lorenzo Iorio
Collection Editor

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