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The Pauli measurements (the measurements that can be performed with Clifford operators followed by measurement in the computational basis) are a fundamental object in quantum information. It is well-known that there is no assignment of…

Quantum Physics · Physics 2023-11-16 Leon Bankston

We introduce the Clifford entropy, a measure of how close an arbitrary unitary is to a Clifford unitary, which generalizes the stabilizer entropy for states. We show that this quantity vanishes if and only if a unitary is Clifford, is…

Quantum Physics · Physics 2025-12-30 Gianluca Cuffaro , Matthew B. Weiss

The performance of computational methods for many-body physics and chemistry is strongly dependent on the choice of basis used to cast the problem; hence, the search for better bases and similarity transformations is important for progress…

We provide a recursively defined sequence of flag circuits which will detect logical errors induced by non-fault-tolerant $R_{\overline{Z}}(\frac{\pi}{2^l})$ gates on CSS codes with a fault distance of two. As applications, we give a family…

Quantum Physics · Physics 2026-03-26 Shival Dasu , Ben Criger

Quantum error correction and fault-tolerance have provided the possibility for large scale quantum computations without a detrimental loss of quantum information. A very natural class of gates for fault-tolerant quantum computation is the…

Quantum Physics · Physics 2013-03-12 Tomas Jochym-O'Connor , Yafei Yu , Bassam Helou , Raymond Laflamme

For the complex Clifford algebra Cl(p,q) of dimension n=p+q we define a Hermitian scalar product. This scalar product depends on the signature (p,q) of Clifford algebra. So, we arrive at unitary spaces on Clifford algebras. With the aid of…

Mathematical Physics · Physics 2019-10-21 N. G. Marchuk , D. S. Shirokov

Unitary t-designs are some of the most versatile tools in quantum information theory. Their applications range from randomized benchmarking and shadow tomography, to more fundamental ones such as emulating quantum chaos and establishing…

Quantum Physics · Physics 2026-03-04 Namit Anand , Jeffrey Marshall , Jason Saied , Eleanor Rieffel , Andrea Morello

Is there more to Dirac's gamma matrices than meets the eye? It turns out that gamma zero can be factorized into a product of three operators. This revelation facilitates the expansion of Dirac's space-time algebra to Clifford algebra…

General Physics · Physics 2025-01-07 Wei Lu

Simulating physical systems on near-term quantum computers often requires preparing states within constrained subspaces, like those with fixed particle number or spin. We use Lie algebraic techniques to prove that hardware-efficient gates…

Quantum Physics · Physics 2026-05-05 Andreas Stergiou , Nicolas PD Sawaya

We introduce a hierarchical algorithm for identifying the largest Pauli coefficients of an unknown $n$-qubit quantum state. The algorithm traverses a prefix-based tree whose nodes represent partial sums of squared Pauli coefficients, always…

{\sc CLIFFORD} is a Maple package for computations in Clifford algebras $\cl (B)$ of an arbitrary symbolic or numeric bilinear form B. In particular, B may have a non-trivial antisymmetric part. It is well known that the symmetric part g of…

Rings and Algebras · Mathematics 2007-05-23 Rafal Ablamowicz

At higher energies the present complex quantum theory with its unitary group might expand into a real quantum theory with an orthogonal group, broken by an approximate $i$ operator at lower energies. Implementing this possibility requires a…

High Energy Physics - Theory · Physics 2015-06-25 David R. Finkelstein , Andrei A. Galiautdinov

Variational Quantum Algorithms are promising candidates for near-term quantum computing, yet they face scalability challenges due to barren plateaus, where gradients vanish exponentially relative to system size. Recent conjectures suggest…

Quantum Physics · Physics 2026-05-21 Sabri Meyer , Francesco Scala , Francesco Tacchino , Aurelien Lucchi

Verification of quantum computations is crucial as experiments advance toward fault-tolerant quantum computing. Yet, no efficient protocol exists for certifying states generated in the Magic-State Injection model -- the foundation of…

Quantum Physics · Physics 2025-11-11 Sami Abdul Sater , Maxime Garnier , Thierry Martinez , Harold Ollivier , Ulysse Chabaud

The Clifford algebra of a n-dimensional Euclidean vector space provides a general language comprising vectors, complex numbers, quaternions, Grassman algebra, Pauli and Dirac matrices. In this work, we present an introduction to the main…

Mathematical Physics · Physics 2018-01-23 G. Aragon-Camarasa , G. Aragon-Gonzalez , J. L. Aragon , M. A. Rodriguez-Andrade

In commuting parametric quantum circuits, the Fourier series of the pairwise fidelity can be expressed as the characteristic function of random variables. Furthermore, expressiveness can be cast as the recurrence probability of a random…

Quantum Physics · Physics 2026-03-27 Richard Yu , Jorge Ramirez , Elaine Wong

We construct an explicit algebraic realisation of three fermion generations within a single Clifford algebra, transforming under the full Standard Model $SU(3)_C\times SU(2)_L\times U(1)_Y$ gauge group, in which an intrinsic $S_3$ family…

General Physics · Physics 2026-04-14 Niels Gresnigt

In this work we explore the structure of Clifford algebras and the representations of the algebraic spinors in quantum information theory. Initially we present an general formulation through elements of left minimal ideals in tensor…

Mathematical Physics · Physics 2021-02-03 Marco A. S. Trindade , Sergio Floquet , J. D. M. Vianna

The quantum mechanical formalism doesn't support our intuition, nor does it elucidate the key concepts that govern the behaviour of the entities that are subject to the laws of quantum physics. The arrays of complex numbers are kin to the…

Quantum Physics · Physics 2015-05-13 Bob Coecke

We develop a Clifford algebra approach for 3D Ising model. By utilizing some mathematical facts of the direct product of matrices and their trace, we expand the dimension of the transfer matrices V of the 3D Ising system by adding unit…

General Physics · Physics 2019-04-09 Zhidong Zhang , Osamu Suzuki , Norman H. March