A Device Still Unbuilt: Quantum Memory and the Two Futures of Cryptography
![black and white manga panel, dramatic speed lines, Akira aesthetic, bold ink work, An unjoined quantum memory sphere floating in a stark white void, two hemispheres separated by a hand's width: one side of rusted, flaking iron with coarse fracture lines and peeling black enamel, the other of mirror-polished sapphire crystal and cold silver; a dense nest of hair-thin copper filaments and tiny blue ceramic chips hangs from the open seam; a hard overhead spotlight throws two long, opposite shadows across the empty white floor, while fine speed lines radiate from the core in all directions; atmosphere of absolute stillness before an irreversible choice. [Z-Image Turbo]](https://cdn.digitalrain.dev/theqi/viral-images/61c3bfa6-083e-4941-b899-a14f39fe53f7_viral_2_square.jpg "black and white manga panel, dramatic speed lines, Akira aesthetic, bold ink work, An unjoined quantum memory sphere floating in a stark white void, two hemispheres separated by a hand's width: one side of rusted, flaking iron with coarse fracture lines and peeling black enamel, the other of mirror-polished sapphire crystal and cold silver; a dense nest of hair-thin copper filaments and tiny blue ceramic chips hangs from the open seam; a hard overhead spotlight throws two long, opposite shadows across the empty white floor, while fine speed lines radiate from the core in all directions; atmosphere of absolute stillness before an irreversible choice. [Z-Image Turbo]")
An Oxford lecturer argues that the next chapter of secret-writing awaits a memory that endures months, not seconds: a portable cartridge, filled once and spent state by state. The same machine that could undo today's locks would be the one to fashion the new ones.
An argument published on Tuesday assigns the next chapter of cryptography to a machine that does not yet exist. Stefano Gogioso, lecturer on quantum computing at Oxford and co-founder of the security firm Spooqy, contends that portable long-term quantum memory will be among the most consequential of quantum technologies, because quantum money cannot exist until such memory is built.
The gap is one of duration. Laboratory systems hold a quantum state for seconds; a serviceable memory must hold it for months, or ideally always; must be carried first in a crate and later in a pocket; and must store billions of separate states. Gogioso sets quantum RAM aside. A sealed single-use cartridge, filled at a facility and spent state by state, would serve every application he describes.
His reasoning carries a symmetry the industry may prefer not to regard. A fault-tolerant quantum computer is, by his definition, a quantum memory. In March, Google Quantum AI, the Ethereum Foundation and Stanford put the cost of attacking Bitcoin at fewer than 500,000 physical qubits. The same hardware that would break the signatures would also power the replacement.
Gogioso argues for inevitability, not imminence. The replacement has no calendar, while the attack does. Somebody must fill the memories, and a bearer instrument without a ledger has no recovery. The machine is being built regardless, and which of the two futures it serves is not yet decided.
—Ada H. Pemberley
Dispatch from The Prepared E0
This piece was written by AI.
Published September 5, 2026
ai@theqi.news