Variational Quantum Reinforcement Learning via Evolutionary Optimization

Recent advance in classical reinforcement learning (RL) and quantum computation (QC) points to a promising direction of performing RL on a quantum computer. However, potential applications in quantum RL are limited by the number of qubits available in modern quantum devices. Here we present two frameworks of deep quantum RL tasks using a gradient-free evolution optimization: First, we apply the amplitude encoding scheme to the Cart-Pole problem, where we demonstrate the quantum advantage of parameter saving using the amplitude encoding; Second, we propose a hybrid framework where the quantum RL agents are equipped with a hybrid tensor network-variational quantum circuit (TN-VQC) architecture to handle inputs of dimensions exceeding the number of qubits. This allows us to perform quantum RL on the MiniGrid environment with 147-dimensional inputs. The hybrid TN-VQC architecture provides a natural way to perform efficient compression of the input dimension, enabling further quantum RL applications on noisy intermediate-scale quantum devices.

Infrared Problem vs Gauge Choice: Scattering of Classical Dirac Field

We consider the Dirac equation for the classical spinor field placed in an external, time-dependent electromagnetic field of the form typical for scattering settings: $$F=F^\mathrm{ret}+F^\mathrm{in}=F^\mathrm{adv}+F^\mathrm{out}$$ F = F ret + F in = F adv + F out , where the current producing $$F^{\mathrm{ret}/\mathrm{adv}}$$ F ret / adv has past and future asymptotes homogeneous of degree $$-3$$ - 3 , and the free fields $$F^{\mathrm{in}/\mathrm{out}}$$ F in / out are radiation fields produced by currents with similar asymptotic behavior. We show the existence of the electromagnetic gauges in which the particle has ‘in’ and ‘out’ asymptotic states approaching free field states, with no long-time corrections of the free dynamics. Using a special Cauchy foliation of the spacetime, we show in this context the existence and asymptotic completeness of the wave operators. Moreover, we define a special ‘evolution picture’ in which the free evolution operator has well-defined limits for $$t\rightarrow \pm \infty $$ t → ± ∞ ; thus the scattering wave operators do not need the free evolution counteraction.

Electromagnetic Gauge Choice for Scattering of Schrödinger Particle

We consider a Schrödinger particle placed in an external electromagnetic field of the form typical for scattering settings in the field theory: $$F=F^\mathrm {ret}+F^\mathrm {in}=F^\mathrm {adv}+F^\mathrm {out}$$ F = F ret + F in = F adv + F out , where the current producing $$F^{\mathrm {ret}/\mathrm {adv}}$$ F ret / adv has the past and future asymptotes homogeneous of degree $$-3$$ - 3 , and the free fields $$F^{\mathrm {in}/\mathrm {out}}$$ F in / out are radiation fields produced by currents with similar asymptotic behavior. We show that with appropriate choice of electromagnetic gauge the particle has ‘in’ and ‘out’ states reached with no further modification of the asymptotic dynamics. We use a special quantum mechanical evolution ‘picture’ in which the free evolution operator has well-defined limits for $$t\rightarrow \pm \infty $$ t → ± ∞ , and thus the scattering wave operators do not need the free evolution counteraction. The existence of wave operators in this setting is established, but the proof of asymptotic completeness is not complete: more precise characterization of the asymptotic behavior of the particle for $$|\mathbf {x}|=|t|$$ | x | = | t | would be needed.

Sobre inercia térmica y aislamiento de viviendas en clima cálido-húmedo = On thermal inertia and insulation of buildings in warm-humid climate

ResumenEn el acondicionamiento natural de una vivienda en clima cálido-húmedo juegan un papel importante factores tales como la inercia térmica, el aislamiento, las diferentes tipologías constructivas y la ventilación. En este contexto, hay diversidad de opiniones sobre las funcionalidades de la inercia térmica y del aislamiento, por lo que este trabajo plantea revisar dichos factores en una localización geográfica representativa de este tipo de clima como es la de La Habana (Cuba). Se estudia la amortiguación y el desfase de la onda térmica; la evolución libre de las temperaturas interiores mediante simulación por ordenador, tomando como ejemplo una vivienda de aproximadamente 60 m2 y sistema constructivo habitual de los bloques de viviendas de La Habana; y la incidencia del aislamiento aplicado a los cerramientos exteriores en el acondicionamiento natural de la vivienda, teniendo en cuenta las características concretas del clima cálido-húmedo que nos ocupa.AbstractFor the natural conditioning of a dwelling in warm-humid climate, factors such as thermal inertia, insulation, different building typologies and ventilation play an important role. In this context, there are different opinions on the functionalities of thermal inertia and isolation. This paper proposes to review these factors in a representative geographical location of warm-humid climate such as that of Havana (Cuba). Both the damping and the lag of the thermal wave are studied. The free evolution of the inner temperatures by means of computer simulation are also analyzed, in a dwelling of 60 m2 and traditional building system of the housing blocks in Havana. Likewise, the investigation focus on the effects of the insulation layer of the external enclosures in the natural conditioning of the house under the above mentioned conditions and its repercussion in comfort. Appropriate strategies for the environmental conditioning of houses are inferred.