By RIKEN | 5 min read
RIKEN researchers have identified and corrected a hidden source of error that degrades silicon spin qubits when several share a single microwave control line. The culprit is the AC Stark shift, in which control signals meant for one qubit shift the energy levels of its neighbors and introduce unwanted phase errors. The team's fix relies on pairwise calibrations rather than calibrating every combination of qubits, which keeps the method practical as systems grow. Running five qubits on one shared line, they held single-qubit gate fidelity above 99.99% with up to three qubits active and about 99.9% with all five operating at once. Published in Nature Physics, the result strengthens the case for shared control lines as the path to scaling silicon processors built with existing chip manufacturing, though drive-induced decoherence at higher microwave power still needs to be solved.
By Felix Ng | 2 min read
Hardware wallet maker Keystone has disclosed a website breach that exposed customer names, contact details, shipping addresses, and order records to an unauthorized third party. The company confirmed the incident after reviewing API activity with Shopify, says it has closed the vulnerability, and is notifying affected customers, but it has not said how many were affected. Buyers who ordered devices more than two years ago also received breach notices, raising questions about Keystone's 2023 pledge to keep customer data for only 180 days. The stakes extend beyond phishing: CertiK recorded 52 verified wrench attacks, in which criminals use physical threats against crypto holders, in the first half of 2026, up 33% from a year earlier. The incident shows that a self-custody device is only as private as the e-commerce stack that sold it.
By Christian Saclao | 5 min read
Physicists are developing the idea of a "time qubit," a quantum bit held in a superposition of two opposite directions of quantum evolution, rather than a device that reverses time itself. The concept, introduced by Tel Aviv University physicist Yakov Bloch in a November 2025 preprint, has been extended by Korea University's Tai Hyun Yoon into a framework that uses entangled photon pairs from two crystals driven by the same laser. Shifting the light's phase by half a cycle reverses one interaction term, while the shared laser erases information about which crystal produced a photon so the opposing evolutions can interfere. Yoon argues that data from a 2018 experiment his team ran for another purpose already shows behavior consistent with a single-photon time qubit. The work is an unreviewed arXiv preprint rather than a definitive demonstration, but if confirmed it could open routes to temporal quantum error correction, high-dimensional qudit processing, and tabletop simulations of relativistic physics.
Spiral’s Edge
This NASA Hubble Space Telescope image released on Oct. 16, 2026, features the edge-on, intermediate spiral galaxy NGC 1827, located roughly 37 million light-years away in the constellation Columba, the Dove. Hubble captured the image as part of a survey looking at 260 satellite galaxies around 22 Milky Way-like host galaxies within a radius of about 32 million light-years from Earth. Low-mass galaxies like the ones in this Hubble observing program provide a way to test the predictions of cosmological models on small scales, which struggle to match observations.
Image credit: NASA, ESA, Michael Jones (California Institute of Technology); Image Processing: Gladys Kober (NASA/Catholic University of America)
