Chronological feed of everything captured from Daniel Gottesman.
This paper demonstrates fundamental limitations in achieving fault-tolerant implementations of the full Clifford group for quantum codes encoding multiple logical qubits. Through a series of no-go theorems, it
This paper significantly refines the upper bound for $N_0$, the minimum number of qubits required for an eventually universal quantum gate set to achieve universality. The previous bound of $d^8n$ is reduced to $d^4n$, offering a more precise understanding of the qubit scaling required for universal quantum computation. This improved bound has practical implications for the design and analysis of quantum computing systems.
A novel method combining quantum-inspired algorithms and quantum information processing dramatically reduces the photon requirement for measuring gravitational microlensing time delays. This advancement enables observations previously impossible due to photon flux and signal coherence constraints. The technique saturates a provable lower bound on photon count, offering significant improvements for both calibrating optical interferometric telescopes and direct mass measurements of microlensing events.
The rotation-invariant Hamiltonian problem, a variant of the local Hamiltonian problem with translational and rotational lattice invariance, is proven to be QMA$_{EXP}$-complete. This complexity holds even with arbitrary but fixed lattice dimensions and scaled lattice lengths, extending previous findings for one-dimensional cases and addressing an open question in computational complexity.
This paper presents a general framework for fault-tolerant quantum computation encoded in Majorana hardware (nanowires and neutral fermionic atoms), closing a gap where prior schemes were either code-family-specific or incomplete. The authors address the even/odd Majorana code distinction systematically, deriving transversal Clifford gadgets, a Steane-inspired fault-tolerant measurement scheme, and a novel quantum reference frame construction for odd codes that circumvents parity superselection constraints. Notably, they also identify odd Majorana codes with transversal T gates and construct a high-rate quantum LDPC Majorana code, demonstrating that all required primitives for universal fault-tolerant computation are realizable on fermionic hardware.