#iccr

ICCR India Chair MoU signed at Tel Aviv University | The Jerusalem PostJerusalem Post/Israel News Marking a new milestone in India–Israel academic cooperation. TAU President Prof. Ariel Porat and H.E. Mr. J.P. Singh, Ambassador of India to Israel.(photo credit: CHEN GALILI)ByJERUSALEM POST STAFFDECEMBER 16, 2025 15:18

ICCR News New Method Reveals ‘Quantum Magic’ in Massive Quantum Systems: Simulation Leap Scientists' revolutionary computer technology, Iterative Clifford Circuit Renormalisation (ICCR), could revolutionise quantum system understanding and modelling. This novel approach aims to overcome the exponential computing cost of conventionally recreating many-body quantum states, especially ones with “non-stabilizerness,” or quantum magic. Classical simulation of quantum many-body systems has long proven difficult in statistical and condensed matter physics. Because simulating a many-body quantum state with the number of degrees of freedom requires exponential computing, numerical investigations are limited to the simplest systems. Gaussian, stabiliser, and poorly entangled quantum states can be simulated, but many “non-trivial” states are quite challenging.

Understanding Quantum Magic

Understanding Quantum Magic This complexity comes from "non-stabilizerness," or quantum magic, which evaluates how much a quantum state differs from stabiliser states. This measure affects numerical simulation computational efficiency. Many metrics of magic have been established to examine many-body difficulties and quantum circuits, but their evaluation is too expensive. This restriction has made it harder to study regimes like extremely large system sizes, higher complexity, or highly entangled states that standard tensor network approaches cannot reach.

ICCR Changes Simulation Paradigm

A Simulation Perspective Change The novel ICCR algorithm by Alessio Paviglianiti and colleagues circumvents these limits by drastically modifying quantum simulation. ICCR iteratively adjusts the quantum circuit structure and renormalises the initial state instead of explicitly modelling the quantum state's time development, which is computationally prohibitive. To quickly evaluate an appropriate beginning state, this smart approach integrates the complex dynamics of non-stabilizerness into its flow.

ICCR's Iterative Renormalisation

ICCR Iterative Renormalisation The ICCR technique can represent states that evolve through Clifford circuits, a type of quantum gates that maintain stabiliser states, and possibly measurements even when “doped” with non-Clifford gates like T gates.

The following ICCR steps are crucial:

T-gate Conversion: A “T gadget” converts quantum magic non-Clifford T gates into an equivalent circuit with an ancilla qubit and a projective measurement. Magical elements are reduced to projective measurements. Measurement Removal: ICCR relies on repeatedly removing one projective measurement from the quantum circuit. Pauli String Transformation: Each measurement first acts locally and “swapped” the Clifford unitary gate. It becomes a projective measurement of a new Pauli string acting directly on the beginning state, which may contain several qubits. To simplify, local Clifford rotations modify the basis so that the new Pauli string works as a product of Z Pauli matrices on a subset of qubits. State Renormalisation: The “magic” happens. Next, a suitable set of Clifford unitary gates on a renormalised initial state replaces the projective measurement. This approach fixes one qubit to a simple stabiliser state, reducing one degree of freedom from non-stabilizerness. Tractability approximation: If rigorously renormalised, this new beginning state may grow more complicated. To approximate this renormalised beginning state and make the task reasonable for large systems, the researchers confine it to a variational class of states like Matrix Product States (MPS). Increase the “bond dimension” (χ) of the MPS to improve the approximation.

Unmatched scale and performance

Unmatched Performance and Scale This unique method allows the ICCR algorithm to investigate system sizes up to N = 1000 qubits. The MPS approximation yields O(N²χ³) computational costs per layer and projective measurement. Optimisation results in a cost of O(N²) for circuits with several T gates, far better than traditional methods. Validation, Key Findings Verification and Key Results The team validated the ICCR approach and found significant agreement by comparing its results to typical tensor network simulations. Numerical research shows that non-stabilizerness estimations are more accurate as computational resources increase, with an average inaccuracy of χ⁻¹. Interestingly, the numerical results suggest that finite-χ estimations often yield lower bounds for true magic values. ICCR was used to study a one-dimensional random Clifford circuit with projective measurements “magic purification circuit” in an exciting application. A measurement-induced relaxation dynamics transition of magic measures was found in this work. This change occurs at a critical measurement density of approximately. For measurement rates above the critical point (p > p_c), quantum magic disappears exponentially, indicating that the system has been purified into an almost-stabilizer state. A large degree of non-stabilizerness persists below the critical threshold (p < p_c), decreasing slowly and logarithmically. These results show that magic behaves like entanglement in such systems and correlate with previous studies on measurement-induced transitions in entanglement and mixed-state purification dynamics.

See the Future of Quantum Simulation

Bihar government in association with ICCR for traditional folks of state like of bihar to the world stage

Sr. Pat Daly, Fr. Michael Hoolahan and the SRI Movement

Sr. Pat Daly, OP passed away a few days ago. She was very well known for her work promoting corporate responsibility. Her passing brought back the memory of working with Fr. Michael Hoolahan, CP (who passed away in 2018) and ICCR to help promote economic justice through the Socially Responsible Investment (SRI) Movement. I had the absolute privilege of being involved with these amazing shareholder activist from 2003 to 2010. In the video above Sr. Pat explains how ICCR and the SRI movement work to address corporate responsibility.

My exposure to shareholder activist was a watershed moment that opened my eyes to the creative ways faith-based communities can influence global institutions for the common good. These religious activists utilized their congregation's financial portfolio to enter into dialogue with transnational corporations over several issues of social concern. Fr. Michael and Sr. Pat were very attentive to promoting the use of renewable energy within oil companies and addressing labor and human right violations found in corporate supply chains. This is what shareholder democracy looks like and promoting shareholder democracy is identified by Laudato Si' as an important way to promote our Catholic social principles.

Transnational corporations (TNC's) are powerful economic forces for globalization. Their modus operandi is driven by profit (often measured in short term gain) for their shareholders. Like many others, the religious communities felt powerless to address these global actors in any significant way. But through the Interfaith Center on Corporate Responsibility many of these faith-based communities entered into an association where they would strategically collaborate as shareholders to engage the shareholder community and Corporate Board of Directors to address these issues publicly. They not only had a voice at shareholder meetings but by working together to form shareholder resolutions they had the ability to sway other financial partners to hold these TNC's accountable. Sr. Pat Daly and Fr. Michael Hoolahan were two such actors that would engage corporations at this level.

Bihar government in association with ICCR for traditional folks of state like of bihar to the world stage