Finite Weyl polynomials and the approach to Tsirelson's bound in relativistic scalar quantum field theory
- URL: http://arxiv.org/abs/2608.20926v1
- Date: Fri, 21 Aug 2026 09:42:23 GMT
- Title: Finite Weyl polynomials and the approach to Tsirelson's bound in relativistic scalar quantum field theory
- Abstract summary: We construct four bounded Hermitian operators, each one a finite in the unitary Weyl operators.<n>We show that the supremum over the finite-polynomial family equals $2sqrt$, although no finite member attains it.
- Score: 0.0
- License: http://arxiv.org/licenses/nonexclusive-distrib/1.0/
- Abstract: We construct four bounded Hermitian operators, each one a finite polynomial in the unitary Weyl operators, for the Bell-CHSH inequality in a free massive scalar field in $1+1$ dimensions. The operators are localized in complementary wedges. Odd Weyl harmonics provide two exactly anticommuting axis observables in each wedge, while normalizable packets with compact support in the spectrum of the boost generator give exact modular inner products at nonvanishing bandwidth. The resulting Bell-CHSH correlator is a finite double sum. An operator with six Weyl terms per axis already gives $2.14885$. Using normalized Fejér approximants of $\operatorname{sgn}(\cos(x))$, we show that the supremum over the finite-polynomial family equals $2\sqrt{2}$, although no finite member attains it; a degree-$511$ example gives $2.80027$. We also point out that, in a centered quasifree state, a Bell-CHSH test whose four final settings are bounded functions of individual quadratures admits one common Gaussian representation and therefore stays below $2$. The finite-Weyl construction avoids this restriction because Bob's final settings mix two noncommuting axis observables.
Related papers
- The I3322 quantum value is attained spatially but not in finite dimension [0.0]
Let $S$ be the quantum supremum of the $I_3322$ Bell functional in the Collins-Gisin normalization (classical bound 0; two-qubit maximum exactly 1/4)<n>We prove: (i) no finite-dimensional quantum strategy attains $S$ -- any finite local dimensions, pure or mixed states, projective or POVM measurements -- proving Pal and Vertesi (2010)<n>We also determine the dimension complexity: with $S_d$ the optimum at local dimension $le d$ and $D()=mind:S-S_d
arXiv Detail & Related papers (2026-09-03T15:48:01Z) - $p$-Form Gauge Dynamics and Digital Quantum Simulation -- Flux and Cosmological Constant Neutralization [0.0]
I develop a Hamiltonian framework for $mathbb Z_k$ $p$-form gauge fields on arbitrary oriented cell complexes.<n>I specialize to $p=2, k=2$, where the magnetic 3-cell term is absent and the one-form Gauss-law can be solved exactly.
arXiv Detail & Related papers (2026-07-12T22:57:37Z) - Regularized Online RLHF with Generalized Bilinear Preferences [68.44113000390544]
We consider the problem of contextual online RLHF with general preferences.<n>We adopt the Generalized Bilinear Preference Model to capture preferences via low-rank, skew-symmetric matrices.<n>We prove that the dual gap of the greedy policy is bounded by the square of the estimation error.
arXiv Detail & Related papers (2026-02-26T15:27:53Z) - Robustly self-testing all maximally entangled states in every finite dimension [1.2499537119440245]
We prove a device-independent, noise-tolerant certification of maximally entangled states in every finite dimension $d$.<n>The protocol uses standard Heisenberg-Weyl operations and non-Clifford phase gates that are diagonal in the computational basis.
arXiv Detail & Related papers (2025-08-01T21:02:07Z) - Convergence Rates for the Trotter Splitting for Unbounded Operators [6.246102028831753]
We study convergence rates of the Trotter splitting $eA+L = lim_n to infty (eL/n eA/n)n$ in the strong operator topology.<n>We derive convergence rates for the Schr"odinger operator with $V(x)=pm |x|-a$ potential.
arXiv Detail & Related papers (2024-07-04T16:37:54Z) - Rigorous derivation of the Efimov effect in a simple model [68.8204255655161]
We consider a system of three identical bosons in $mathbbR3$ with two-body zero-range interactions and a three-body hard-core repulsion of a given radius $a>0$.
arXiv Detail & Related papers (2023-06-21T10:11:28Z) - Annihilating Entanglement Between Cones [77.34726150561087]
We show that Lorentz cones are the only cones with a symmetric base for which a certain stronger version of the resilience property is satisfied.
Our proof exploits the symmetries of the Lorentz cones and applies two constructions resembling protocols for entanglement distillation.
arXiv Detail & Related papers (2021-10-22T15:02:39Z) - Quantum double aspects of surface code models [77.34726150561087]
We revisit the Kitaev model for fault tolerant quantum computing on a square lattice with underlying quantum double $D(G)$ symmetry.
We show how our constructions generalise to $D(H)$ models based on a finite-dimensional Hopf algebra $H$.
arXiv Detail & Related papers (2021-06-25T17:03:38Z) - Exact one- and two-site reduced dynamics in a finite-size quantum Ising
ring after a quench: A semi-analytical approach [4.911435444514558]
We study the non-equilibrium dynamics of a homogeneous quantum Ising ring after a quench.
The long-timescale reduced dynamics of a single spin and of two nearest-neighbor spins is studied.
arXiv Detail & Related papers (2021-03-23T13:14:50Z) - Nonparametric approximation of conditional expectation operators [0.3655021726150368]
We investigate the approximation of the $L2$-operator defined by $[Pf](x) := mathbbE[ f(Y) mid X = x ]$ under minimal assumptions.
We prove that $P$ can be arbitrarily well approximated in operator norm by Hilbert-Schmidt operators acting on a reproducing kernel space.
arXiv Detail & Related papers (2020-12-23T19:06:12Z) - Anharmonic oscillator: a solution [77.34726150561087]
The dynamics in $x$-space and in $(gx)-space corresponds to the same energy spectrum with effective coupling constant $hbar g2$.
A 2-classical generalization leads to a uniform approximation of the wavefunction in $x$-space with unprecedented accuracy.
arXiv Detail & Related papers (2020-11-29T22:13:08Z) - Scattering data and bound states of a squeezed double-layer structure [77.34726150561087]
A structure composed of two parallel homogeneous layers is studied in the limit as their widths $l_j$ and $l_j$, and the distance between them $r$ shrinks to zero simultaneously.
The existence of non-trivial bound states is proven in the squeezing limit, including the particular example of the squeezed potential in the form of the derivative of Dirac's delta function.
The scenario how a single bound state survives in the squeezed system from a finite number of bound states in the finite system is described in detail.
arXiv Detail & Related papers (2020-11-23T14:40:27Z)
This list is automatically generated from the titles and abstracts of the papers in this site.
This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.