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A Jupiter-size planet that escaped its star's death

WD 1856 b is the only confirmed case of a planet that survived the death of a Sun-like star. It’s a Jupiter-size world orbiting a white dwarf—the burned-out remnant of a Sun-like star. Now, a team of astronomers has used the James Webb Space Telescope to take a closer look at this planet for the first time, and what they found makes an already strange system even stranger.

A feeding frenzy

WD 1856 b was an accidental discovery. Astronomers pointed the TESS observatory at a sample of roughly 2,000 white dwarfs in 2020. These stars are the remains of a Sun-like star that have already gone through a red-giant phase, leaving behind an Earth-size body that’s primarily composed of elements like carbon and oxygen. The TESS team was searching for small objects like comets or asteroids that might transit across the face of these dead stars.

What they found in the WD 1856 system was a gas giant. “As soon as they looked at it, they said, okay, that’s weird,” said Christopher O’Connor, a theoretical astrophysicist at Cornell University and co-author of the recent Nature study on WD 1856 b.

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© NASA, ESA, CSA, R. Crawford

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Quantum error correction can constantly recalibrate a processor

There are some obvious big picture issues that stand between us and useful quantum computing. Issues like whether we can make enough high-quality hardware qubits to connect into the error-corrected logical qubits we need, and how we generate the states needed to perform universal computation on those logical qubits. But there are also many less prominent challenges that will need to be solved before we can perform calculations.

One of those challenges, which only affects some types of hardware, is calibration. For devices we manufacture, like superconducting qubits, there are always subtle variations among individual qubits. (This is not true when we use something like an atom to hold the qubit, but the lasers that control them can drift.) As a result, this hardware is put through a process called calibration, where we test different frequencies and amplitudes of the microwave pulses that control them to find the combination that produces the lowest error rates, and then save those settings for use in calculations.

However, you can't perform the typical calibration process while you're doing calculations, which means drift becomes an issue for long and complicated algorithms. Google, though, has figured out that it's possible to do calibration using the same data that's used for error correction.

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