Aleph - 0.37.0

✨ New Features

• New mathematical functions for arithmetic types: bessel_j, bessel_y, bessel_i, and bessel_k for computing Bessel functions of the first kind, second kind, modified Bessel functions of the first kind, and modified Bessel functions of the second kind, respectively.
• The Fermionic operator PairHopSum(tensor) represents a Hermitian sum of pair hopping terms: $\sum_{i,j,k,l} V_{ijkl} a_{i}^\dagger a_{j}^\dagger a_{k} a_{l}$. It differs from CoulombSum in that the pair hopping terms do not include spin indices (which introduces an additional constraint).
• Added adjointed() member function to quantum Operators to dynamically compute the Hermitian conjugate.
• Quantum Operators support .is_hermitian(), .is_unitary(), and .is_real() dynamic introspection properties.
• Expanded the library of symbolic SpinHalf operators in Aleph, adding standardized factory functions for new parameter interactions:
  • PhaseShift(angle, i): Single-qubit phase gate operator.
• Model can now be initialized from .lattice_model files by passing the path to the file to the model constructor (e.g. model("path/to/model.lattice_model")).
• the Model class now has a method to inspect labels that need to be registered model.unregistered_labels().
• The set_coefficient method can now also take an aleph function that takes a coordinate and returns a complex number.

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🐛 Fixes

• Fixed data service downloads and uploads for files whose paths contain spaces or other URL-special characters.
• Fixed an error in PairRotation where sparse vectors were not correctly multiplied, causing incorrect results.

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⚠️ Breaking Changes

• To align with the standard for CoefficientFunction, Model::set_coefficient now expects a complex number instead of a real number.

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