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Small black holes were nowhere to be found, leading astronomers to wonder if they didn’t exist at all. Now a series of findings, including a “unicorn” black hole, has raised hopes of solving the decade-long mystery.
Since they can’t prod actual universes as they inflate and bump into each other in the hypothetical multiverse, physicists are studying digital and physical analogs of the process.
For decades, astronomers debated whether a particular smudge was close-by and small, or distant and huge. A new X-ray map supports the massive option.
We don’t know why the universe appears to be expanding faster than it should. New ultra-precise distance measurements have only intensified the problem.