Researchers Models Deformed Polaron-Molecule Hamiltonian for Quantum-Gravity Phenomenology

Ezequiel Valero and colleagues at the University of Valencia demonstrate that many-body observables exhibit significant sensitivity to ultraviolet (UV) deformations originating from generalised-uncertainty-principle and modified-dispersion-relation theories, even at accessible energy scales. They constructed a deformed polaron-molecule Hamiltonian, carefully preserving the infrared sector, to quantify the impact of these deformations on both spectral and Ramsey observables and subsequently implemented the corresponding quantum dynamics utilising a quantum computing platform. The study identifies specific regimes proximate to the polaron-molecule crossover where even minute UV deformations are sharply amplified, potentially leading to measurable alterations in quasiparticle properties and spectral response, and reports experimental validation performed on the QRed superconducting quantum processor. These findings provide a defined pathway for investigating low-energy quantum-gravity phenomenology within a controlled many-body system and delineate the limits of the effective description employed.

Ultraviolet Sensitivity Amplified via Polaron-Molecule Hamiltonian Manipulation A tenfold enhancement in the sensitivity of impurity many-body observables to ultraviolet deformations has been achieved by teams from CNS and Universidade Europeia, exceeding previous limitations imposed by the Planck scale, which typically necessitates energies on the order of 1019 GeV for direct observation of quantum gravity effects. This amplified sensitivity, realised through precise manipulation of a deformed polaron-molecule Hamiltonian, facilitates the exploration of quantum-gravity phenomenology at energies now within the realm of experimental feasibility. Previously, detecting such subtle effects demanded energies far exceeding current technological capabilities, rendering direct observation impractical. The polaron-molecule Hamiltonian describes a system where an impurity atom interacts with a surrounding medium, exhibiting characteristics of both a localized polaron and a delocalized molecule, providing a tunable platform for investigating many-body physics. The QRed superconducting quantum processor successfully validated these findings, establishing a novel pathway to investigate low-energy quantum gravity and rigorously define the boundaries of effective theoretical descriptions. Small ultraviolet deformations were amplified in regimes near the polaron-molecule crossover, revealing measurable changes in quasiparticle properties and spectral response. Ramsey interferometry, a highly precise technique employed to measure energy differences between quantum states, verified an increased sensitivity and revealed spectral shifts of up to 0.03; these changes were directly attributable to the imposed ultraviolet deformations within the system. The sensitivity peaked when the system approached the polaron-molecule crossover, a specific interaction strength where the impurity quasiparticle undergoes a transition between a localized and delocalized state, amplifying the effects of the deformations by a factor of approximately seven compared to other interaction regimes. This amplification arises from the increased susceptibility of the quasiparticle to external perturbations at the crossover point. The QRed processor successfully simulated the dynamics of up to six fermionic atoms interacting with the impurity, validating the theoretical predictions and confirming the enhanced sensitivity within a meticulously controlled quantum environment. This development represents a significant step towards leveraging quantum computers for probing fundamental physics beyond the reach of classical computation.

Exploring Modified Physics via Impurity Many-body Observables on a Superconducting Quantum Processor Precise control and manipulation of the QRed superconducting quantum processor at BSC-CNS were central to enabling this research. The processor functioned as a controlled laboratory to test how changes predicted by theoretical models, specifically those relating to modified gravity, might manifest within a complex quantum system, deliberately avoiding a direct simulation of quantum gravity itself, which remains computationally intractable. This involved constructing a detailed mathematical description of interacting particles and then subtly altering its parameters to mimic the effects of modified physics at tiny scales, focusing on measurable properties particularly sensitive to these alterations. The superconducting qubits within the QRed processor were carefully calibrated and entangled to represent the interacting particles, allowing for the simulation of their quantum dynamics. The choice of a superconducting platform offers advantages in terms of coherence times and controllability, crucial for maintaining the integrity of the quantum simulation. Detecting quantum gravity signals via amplified sensitivities in deformed polaron-molecule Teams at BSC-CNS and Universidade Europeia have demonstrated a promising pathway to detect subtle effects potentially linked to quantum gravity, but the current work relies heavily on a specific model, the deformed polaron-molecule Hamiltonian, and does not address whether these amplified sensitivities are universal across all many-body systems. A crucial question remains regarding the extent to which these observed changes definitively confirm predictions stemming from quantum gravity, versus alternative explanations not yet fully explored, such as systematic errors or unaccounted-for interactions within the system. This work establishes a clear route to explore low-energy quantum-gravity phenomenology using a well-defined many-body platform, meticulously observing its behaviour under controlled conditions. The use of impurity many-body observables allows for a focused investigation of the system’s response to external perturbations. Subtle ultraviolet deformations were amplified by concentrating on impurity many-body observables, potentially linking to modifications of fundamental physical principles governing spacetime at the Planck scale. Experimental validation confirms that these amplified sensitivities are detectable with current technology, circumventing the need for extremely high-energy experiments that are currently beyond our reach. It is vital to acknowledge that these amplified sensitivities are contingent upon the chosen model and the specific parameters employed. Nevertheless, the authors have established a clear, testable pathway linking subtle changes in many-body systems to potential quantum gravity effects, providing a framework for future investigations. Identifying specific regimes where ultraviolet distortions are magnified offers a focused strategy for future investigations into low-energy quantum gravity phenomena, potentially paving the way for a deeper understanding of the universe at its most fundamental level. Further research will be needed to explore the generality of these findings and to investigate alternative theoretical models that could explain the observed effects. The research demonstrated that subtle changes at very high energy scales, known as ultraviolet deformations, can be significantly amplified when observing impurity many-body observables. This matters because it provides a way to potentially explore quantum gravity effects using relatively low-energy experiments on platforms like the QRed superconducting quantum processor. Researchers quantified the impact of these deformations using a deformed polaron-molecule Hamiltonian and observed corresponding changes in spectral and Ramsey observables. The authors intend to explore whether these amplified sensitivities are universal across different many-body systems and to investigate alternative explanations for the observed effects. 👉 More information 🗞 Sensitivity of polaron-molecule observables to MDR/GUP-like ultraviolet deformations at low energies via quantum computing 🧠 ArXiv: https://arxiv.org/abs/2606.14479 Stay current. See today’s quantum computing news on Quantum Zeitgeist for the latest breakthroughs in qubits, hardware, algorithms, and industry deals. Tags: