2022
Luca Taggliacozzo; (IFF CSIC)
Universality at an out of equilibrium, from tensor networks, to lattice gauge theories through quantum circuits Presentation
07.04.2022.
@misc{,
title = {Universality at an out of equilibrium, from tensor networks, to lattice gauge theories through quantum circuits},
author = {Luca Taggliacozzo; (IFF CSIC)},
year = {2022},
date = {2022-04-07},
urldate = {2022-04-07},
abstract = { I will review the role of universality at equilibrium and its effect on approximate simulations with tensor networks and quantum circuits. This will motivate our quest for identifying universal properties of systems out of equilibrium. In that context, I will discuss some features of universal entanglement spectra for the Ising and Potts model in 1+1D. I will conclude by discussing the presence of a new critical point in the phase diagram of the Abelian Higgs model in 1+1D at theta=0.},
keywords = {},
pubstate = {published},
tppubtype = {presentation}
}
I will review the role of universality at equilibrium and its effect on approximate simulations with tensor networks and quantum circuits. This will motivate our quest for identifying universal properties of systems out of equilibrium. In that context, I will discuss some features of universal entanglement spectra for the Ising and Potts model in 1+1D. I will conclude by discussing the presence of a new critical point in the phase diagram of the Abelian Higgs model in 1+1D at theta=0.
Diego Garcia Martin; (Barcelona Supercomputing Center, IFT CSIC-UAM)
Theory of overparametrization in quantum neural networks Presentation
17.03.2022.
@misc{nokey,
title = {Theory of overparametrization in quantum neural networks},
author = {Diego Garcia Martin; (Barcelona Supercomputing Center, IFT CSIC-UAM)},
year = {2022},
date = {2022-03-17},
urldate = {2022-03-17},
abstract = {Overparametrization refers to a computational phase transition that takes place in variational quantum algorithms when the number of parameters increases beyond a certain critical value. In this talk, I'll explain how the onset of overparametrization can be related to the dimension of the dynamical Lie algebra of the generators of the quantum circuit, and how this leads to a natural interpretation of the phenomenon in terms of the available directions in projective Hilbert space during the optimization.},
keywords = {},
pubstate = {published},
tppubtype = {presentation}
}
Overparametrization refers to a computational phase transition that takes place in variational quantum algorithms when the number of parameters increases beyond a certain critical value. In this talk, I’ll explain how the onset of overparametrization can be related to the dimension of the dynamical Lie algebra of the generators of the quantum circuit, and how this leads to a natural interpretation of the phenomenon in terms of the available directions in projective Hilbert space during the optimization.
Enrique Rico; (Ikerbasque research associate, UPV)
Synergies between quant-ph and hep-th Presentation
03.03.2022.
@misc{,
title = {Synergies between quant-ph and hep-th},
author = {Enrique Rico; (Ikerbasque research associate, UPV)},
year = {2022},
date = {2022-03-03},
urldate = {2022-03-03},
abstract = {Quantum Simulation of Light-Front Parton Correlators
M. G. Echevarria, I. L. Egusquiza, E. Rico, and G. Schnell
arXiv:2011.01275
Phys. Rev. D 104, 014512 (2021)
The physics of high-energy colliders relies on the knowledge of different nonperturbative parton correlators, such as parton distribution functions, that encode the information on universal hadron structure and are thus the main building blocks of any factorization theorem of the underlying process in such collision. These functions are given in terms of gauge-invariant light-front operators, that are nonlocal in both space and real time, and thus intractable by standard lattice techniques due to the well-known sign problem. In this paper, we propose a quantum algorithm to perform a quantum simulation of these type of correlators, and illustrate it by considering a space-time Wilson loop. We discuss the implementation of the quantum algorithm in terms of quantum gates that are accessible within actual quantum technologies such as cold atoms setups, trapped ions or superconducting circuits.
Qubit alive thanks to the anomaly
I.L. Egusquiza, A. Iñiguez, E. Rico, A. Villarino
arXiv:2109.11824
We present an exact full symmetry analysis of the 0-π superconducting circuit. We identify points in control parameter space of enhanced anomalous symmetry, which imposes robust twofold degeneracy of its ground state, that is for all values of the energy parameters of the model. We show, both analytically and numerically, how this anomalous symmetry is maintained in the low-energy sector, thus providing us with a strong candidate for robust qubit engineering.},
keywords = {},
pubstate = {published},
tppubtype = {presentation}
}
Quantum Simulation of Light-Front Parton Correlators
M. G. Echevarria, I. L. Egusquiza, E. Rico, and G. Schnell
arXiv:2011.01275
Phys. Rev. D 104, 014512 (2021)
The physics of high-energy colliders relies on the knowledge of different nonperturbative parton correlators, such as parton distribution functions, that encode the information on universal hadron structure and are thus the main building blocks of any factorization theorem of the underlying process in such collision. These functions are given in terms of gauge-invariant light-front operators, that are nonlocal in both space and real time, and thus intractable by standard lattice techniques due to the well-known sign problem. In this paper, we propose a quantum algorithm to perform a quantum simulation of these type of correlators, and illustrate it by considering a space-time Wilson loop. We discuss the implementation of the quantum algorithm in terms of quantum gates that are accessible within actual quantum technologies such as cold atoms setups, trapped ions or superconducting circuits.
Qubit alive thanks to the anomaly
I.L. Egusquiza, A. Iñiguez, E. Rico, A. Villarino
arXiv:2109.11824
We present an exact full symmetry analysis of the 0-π superconducting circuit. We identify points in control parameter space of enhanced anomalous symmetry, which imposes robust twofold degeneracy of its ground state, that is for all values of the energy parameters of the model. We show, both analytically and numerically, how this anomalous symmetry is maintained in the low-energy sector, thus providing us with a strong candidate for robust qubit engineering.
M. G. Echevarria, I. L. Egusquiza, E. Rico, and G. Schnell
arXiv:2011.01275
Phys. Rev. D 104, 014512 (2021)
The physics of high-energy colliders relies on the knowledge of different nonperturbative parton correlators, such as parton distribution functions, that encode the information on universal hadron structure and are thus the main building blocks of any factorization theorem of the underlying process in such collision. These functions are given in terms of gauge-invariant light-front operators, that are nonlocal in both space and real time, and thus intractable by standard lattice techniques due to the well-known sign problem. In this paper, we propose a quantum algorithm to perform a quantum simulation of these type of correlators, and illustrate it by considering a space-time Wilson loop. We discuss the implementation of the quantum algorithm in terms of quantum gates that are accessible within actual quantum technologies such as cold atoms setups, trapped ions or superconducting circuits.
Qubit alive thanks to the anomaly
I.L. Egusquiza, A. Iñiguez, E. Rico, A. Villarino
arXiv:2109.11824
We present an exact full symmetry analysis of the 0-π superconducting circuit. We identify points in control parameter space of enhanced anomalous symmetry, which imposes robust twofold degeneracy of its ground state, that is for all values of the energy parameters of the model. We show, both analytically and numerically, how this anomalous symmetry is maintained in the low-energy sector, thus providing us with a strong candidate for robust qubit engineering.