Quantum Mind#

Quantum robotics: computing, sensing and cognition, each against its classical baseline.

Quantum Mind is an open-source Python library for the three threads of quantum robotics: quantum computing for robot algorithms (robot problems as optimisation, with classical baselines and a Qiskit QAOA adapter), quantum sensing (quantum-limited sensor models and their fusion with classical sensors) and quantum-probability cognition (how people judge, decide and trust, and how a robot should read them). Every model sits next to the classical model it has to beat, and every belief ends in a cost-aware decision.

Version 3.1.0Apache-2.0Python 3.10 to 3.12 Qiskit 2.xIBM QuantumAmazon BraketNumPy-style API

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pip install "quantum-mind[all]"
1 · Quantum computing for robots

Multi-robot allocation, grasp selection and slot scheduling as QUBOs, classical baselines and a thin Qiskit QAOA adapter.

Quantum computing for robot algorithms (quantum_mind.computing)
2 · Quantum sensing for robots

Quantum limits, atom-interferometer and MEMS accelerometer models, and a Kalman filter that fuses them.

Quantum sensing for robots (quantum_mind.sensing)
3 · Quantum-probability cognition

COBRA, a context-rotated density-matrix belief filter, with quantum-like human models and the robot decision layer.

COBRA belief filter (quantum_mind.belief)
Quantum-like human models

Question order, quantum Bayesian networks, trust dynamics and bistable perception, each with classical baselines. Four families.

Quantum-like families
Robot decision layer

Ask or act, question planning, calibration and conformal sets, fusion, trust-aware hand-over and allocation, ROS 2.

Applications
Bloch-sphere viewer

Gate-by-gate trajectories, animations, interactive HTML, live widgets and tomography on real back ends.

Bloch-sphere viewer (quantum_mind.viz)

Author’s view#

Yeshwanth Guru, author and maintainer.

I started Quantum Mind from one belief: a robot that works with people needs a different kind of probability than the one inside most of its filters. People are not neutral sensors. A look changes what a hand movement means, a question changes the answer to the next question, and asking someone whether they trust a robot changes their trust. Classical filters assume the evidence arrives in independent pieces; quantum probability was built for the case where the order and the context of a measurement matter.

Quantum robotics is a young field with at least three threads, and I think it helps to keep them apart: (1) quantum computing for robot algorithms (planning, optimisation, learning), which is promising on paper but has shown no practical advantage on real robot problems with today’s noisy devices; (2) quantum sensing for robots (atomic and solid-state sensors for navigation, magnetometry, gravimetry), which is physical hardware; and (3) quantum-probability models of the beliefs a robot holds about people (context, order and trust), which run on ordinary computers and can be tested today.

Quantum Mind covers all three, because I want to work on the whole umbrella, and it holds each thread to the same standard: a classical baseline, an ablation, and results that are allowed to say no. Thread 1 (quantum_mind.computing) poses robot problems as binary optimisation, supplies the classical baselines and a thin adapter to Qiskit’s QAOA, and does not re-implement what Qiskit and PennyLane do better. Thread 2 (quantum_mind.sensing) models quantum-limited sensors and fuses a slow, stable quantum accelerometer with a fast, drifting classical one in simulation, and does not claim to build a sensor. Thread 3 (quantum_mind.belief) is the quantum-probability model of the beliefs a robot holds about people, the part I have developed furthest. The circuits of the thread-3 models also run on quantum hardware, which is the bridge between the threads. I claim no speed-up anywhere.

In every thread I ask the same question: does the quantum version beat the classical one, and does the robot decide or move better with it? For beliefs about people that becomes: does quantum probability describe human context better than the classical alternative? Every model sits next to the classical model it has to beat, with the ablation that isolates what is new.

I did not re-implement general-purpose quantum algorithms or optimisers (Qiskit, PennyLane and optimisation libraries do them better; thread 1 connects to Qiskit instead), and I limited the scope to AI, machine learning, vision, robotics and embodied AI. Models from the literature are implemented from their papers and cited; the model atlas labels each as published, extended or unique, and the unique ones are my own designs.

I do not claim a quantum computational advantage (QAOA does no better than random sampling on the problems I tested), quantum sensing hardware, or results with real people and robots, and COBRA’s gain is modest and shown only on synthetic data. I want to run a pilot study with a real robot, make COBRA’s training more reliable, run threads 1 and 2 on quantum hardware and measured sensor data, and see others replicate the results. If a claim does not hold, please open an issue.

What is new in this library#

Classical filters treat evidence as arriving in neutral, independent pieces. People and robots do not: a look changes what a hand movement means, a question changes the answer to the next one, and asking about trust changes trust. The quantum-probability formalism represents exactly this, and Quantum Mind turns it into tested code:

  • COBRA, a belief filter whose generalised measurement is rotated by the previous frame, with the Bayes filter and an incoherent filter as built-in limits so the effect of context and the effect of coherence can be separated. On a synthetic task with a context effect it lowers decision cost by about 0.02 against a Bayes filter given enough data (significant in 2 of 5 seeds), but it is worse with little data and slightly worse where context does not matter; the benchmark, the ablations and the cases where it loses are reported in full.

  • Trust as an open quantum system, an order-aware hand-over policy and a value-of-information question planner whose answers depend on the order of the questions.

  • A decision layer that never reports a belief without a cost, a calibration check and a classical baseline.

It runs on ordinary computers and claims no quantum computational advantage.

See the qubits#

A Qiskit circuit, gate by gate. While the two qubits are entangled their Bloch vectors move inside the sphere. Drag to rotate; press play or use the slider.

from qiskit import QuantumCircuit
from quantum_mind.viz import circuit_trajectory, animate_bloch, save_html

qc = QuantumCircuit(2); qc.h(0); qc.cx(0, 1); qc.ry(0.6, 1)
save_html(animate_bloch(circuit_trajectory(qc, steps=15)), 'bell.html')

The two-qubit playground runs the same simulation in the browser.

Where to go next#

Getting started

Install, then fit, compare and simulate in a few lines.

Getting started
Background

Quantum-like cognition from the basics: projections, order effects, interference.

Background
Tutorials

Sixteen step-by-step tutorials, from the introduction to the three threads and a robot loop, with real outputs and figures.

Tutorials
Model atlas

A block diagram for every model: inputs, internals, outputs, baselines and references.

Model atlas
Mathematics

The equations of every model, as the code computes them, from the Born rule to COBRA.

Mathematics
User guide

The layers, every model family, circuits, hardware and the viewer.

User guide
Example gallery

20 runnable scripts on quantum-like models, COBRA, robotics, perception and the viewer.

Example gallery
Notebooks

Interactive Bloch spheres, robot questioning and trust.

Notebooks
API reference

Every public class and function, with parameters, returns and examples.

API reference
Help

Which model do I need, glossary, FAQ and what is validated.

Help
About

Changelog, citing, licence and contributing.

About