string theory string theory

This artist's impression shows the surroundings of a supermassive black hole, typical of that found at the heart of many galaxies. The black hole itself is surrounded by a brilliant accretion disc of very hot, infalling material and, further out, a dusty torus. There are also often high-speed jets of material ejected at the black hole's poles that can extend huge distances into space. L. Calçada/ESO hide caption

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L. Calçada/ESO

Some physicists are pushing back against ideas like string theory and the multiverse. Here, we see a computer-generated image of a black hole, which might, ultimately, be explained by ideas like string theory. Alain Riazuelo/IAP/UPMC/CNRS hide caption

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Alain Riazuelo/IAP/UPMC/CNRS

In the quest to understand our world and the universe in which it sits, Marcelo Gleiser advises: "Not all questions have answers. To hope that science will answer all questions is to want to shrink the human spirit, clip its wings, rob it from its multifaceted existence." Goddard/Arizona State University/NASA hide caption

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Goddard/Arizona State University/NASA

High-energy physics in action: an image of an event in CERN's CMS detector during the search for the Higgs boson. CERN hide caption

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Is Time Real?

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