Aleph - 0.35.0

✨ New Features

• SSE history can now be extracted and manipulated in Aleph allowing for user-implemented estimators.
• Helper function, sse_order to determine the order from a given SSE configuration.
• Added suite of fermionic operator transformation functions to simplify and manipulate fermionic operators:
  • fermionic_site_reorder(operator): Reorders creation and annihilation operators by site while tracking phase changes from anticommutation relations.
  • converted_to_create_destroy(operator): Converts named fermionic operators to their creation/annihilation form. Handles multi-site interactions like density-density ($n_i n_j = c_i^\dagger c_i c_j^\dagger c_j$), hopping ($c_i^\dagger c_j + c_j^\dagger c_i$), and pair operators ($c_i^\dagger c_j^\dagger c_k c_l$).
  • simplified_create_destroy(operator): Simplifies operator products by reordering and removing invalid terms (e.g., $c_i c_i = 0$ and $c_i^\dagger c_i^\dagger = 0$).
  • fused_into_number(operator): Fuses creation-annihilation pairs into number operators ($c_i^\dagger c_i \to n_i$).
  • reduced_number_power(operator): Reduces powers of number operators to at most 1 ($n_i^2 = n_i$ for fermionic systems).

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🐛 Fixes

• Fixed SSE specific heat capacity estimator.

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⚙️ Internal / Technical Changes

• Slight speed improvement to SSE sampling.

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