stringebraic

stringebraic

Stringebraic is a library of methods for representing a Hamiltonian (i.e., a matrix) as a sum of Pauli strings and a quantum state (i.e., a vector) as a sum of bitstrings. This perspective allows for a variety of operations using these strings, such as matrix-vector multiplication, inner products, and other algebraic manipulations.
🐦: Why take this approach?
🐧: Because the computational complexity of these operations typically grows exponentially with the number of qubits—or, equivalently, with the size of the matrix.

In layman's terms, it automates Pauli algebra by:

• removing the concept of matrix and vector size,
• performing the matrix multiplication with string-based rules.

Input Files:

• input_string_list.pkl – A pickle file containing a list of bitstrings that compose the quantum state.
• input_string_coeff_list.pkl – A pickle file containing a list of coefficients that compose the quantum state.
• pauli_matrix_list.pkl – A pickle file containing a list of Pauli strings that compose the Hamiltonian.
• pauli_coeff_list.pkl – A pickle file containing a list of Pauli coefficients that compose the Hamiltonian.

Output:

• The inner product value – A scalar for what the inner product (e.g., expected energy) is.

Installation

It can be installed with pip, ideally by using a virtual environment. Open up a terminal and install the package and the dependencies with:

    pip install stringebraic

or

    python -m pip install stringebraic

🐍 This requires Python 3.8 or newer versions

Steps to fast compute the inner product energy using Pauli string algebra

• Prepare the input files (i.e., converting the quantum Hamiltonian and quantum state into lists of strings and coefficients, as specified in the above section).

• Run the command to generate a inner product (i.e., a scalar):

         stringebraic input_string_list.pkl input_string_coeff_list.pkl pauli_matrix_list.pkl pauli_coeff_list.pkl

Test

You may test the installation using the sample input files (input_string_list.pkl and input_string_coeff_list.pkl, pauli_matrix_list.pkl and pauli_coeff_list.pkl) located in the test folder.

♥ Lastly executed on Python 3.10 on 2025-06-05.