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Ramanujan Quantum Expanders Hit the Bound Exactly
A Weil-representation construction used polylogarithmic gates and ancilla qudits.
Published Updated Story ID: mp-2026-09-30-017
Summary
A Weil-representation construction used polylogarithmic gates and ancilla qudits.
For every odd prime-power q and degree q plus one, the author constructs an infinite family of Ramanujan quantum expanders. The implementation uses O(log-squared N) elementary gates and O(log N) ancilla qudits for dimension N, and satisfies the stated singular-value bound exactly when the circuit is exact.
Why it matters
A Weil-representation construction used polylogarithmic gates and ancilla qudits.
Limits and context
No additional limitation was separately recorded.
Key claims
A Weil-representation construction used polylogarithmic gates and ancilla qudits.
Evidence: source-2026-09-30-019
Sources
- arXiv preprint 2609.38075arXiv · primary research
Corrections
No corrections have been recorded for this story.