Roger Penrose

    Caption: Sir Roger Penrose (1931--) at the Festival della Scienza, Genoa, Italy, 2011.

    Roger Penrose has done many, many things, but he is particularly famous for having shown that black holes can come into existence according to general relativity (GR) and are NOT just solutions allowed by general relativity:

      The importance of Penrose's epoch-making paper "Gravitational Collapse and Space-Time Singularities" (1965) was not its only result, summarised roughly as that if an object such as a dying star implodes beyond a certain point, then nothing can prevent the gravitational field getting so strong as to form some kind of gravitational singularity. It also showed a way to obtain similarly general conclusions in other contexts, notably that of the cosmological Big Bang ... (Slightly edited.)

        ---Wikipedia: Roger Penrose: Research.

    Actually, the gravitational singularity at the center of black holes is probably NOT a point or ring of infinite density as predicted by strict general relativity. It is believed that quantum gravity must prevent collapse to infinite density. The real gravitational singularity must be some exotic quantum mechanical state, but since we have NO confirmed quantum gravity theory, we do NOT know what that state is.

    Penrose's research particularly on black holes has lead to him receiving the 2020 Nobel Prize in Physics shared with Andrea Ghez (1965--) and Reinhard Genzel (1952--) for their investigations of the supermassive black hole Sagittarius A* (AKA Galactic center black hole) at the center of Milky Way (i.e., Galactic center). Sagittarius A* has mass 4.100(34)*10**6 M_☉.

    Penrose also made investigations of Penrose tiling (a form of aperiodic tiling), an advance in artistic design.

    Also, Penrose has written several books (see Wikipedia: Roger Penrose: Works) including The Road to Reality (2004) which is over 1100 pages (counting blank end pages) and is a popular book---but maybe only for physicists. Yours truly has read it---fortunately, Sir Roger gave these sage words "read it as poetry". Actually, yours truly can't find where he said that---so maybe its figment of the imagination.

    Fanfare for Roger Penrose: Trumpet Sonata in D Major, Z. 850: I. (Allegro) | 1:16.

    Credit/Permission: Cirone-Musi, 2011 (uploaded to Wikimedia Commons by User:Flickr_upload_bot, 2012) / CC BY-SA 2.0.
    Image link: Wikimedia Commons: File:Roger Penrose at Festival della Scienza Oct 29 2011.jpg.
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