Standard model physics and the digital quantum revolution: thoughts about the interface

Abstract

Advances in isolating, controlling and entangling quantum systems are transforming what was once a curious feature of quantum mechanics into a vehicle for disruptive scientific and technological progress. Pursuing the vision articulated by Feynman, a concerted effort across many areas of research and development is introducing prototypical digital quantum devices into the computing ecosystem available to domain scientists. Through interactions with these early quantum devices, the abstract vision of exploring classically-intractable quantum systems is evolving toward becoming a tangible reality. Beyond catalyzing these technological advances, entanglement is enabling parallel progress as a diagnostic for quantum correlations and as an organizational tool, both guiding improved understanding of quantum manybody systems and quantum field theories defining and emerging from the Standard Model. From the perspective of three domain science theorists, this article compiles thoughts about the interface on entanglement, complexity, and quantum simulation in an effort to contextualize recent NISQ-era progress with the scientific objectives of nuclear and high-energy physics.

Loop-Free Tensor Networks for High-Energy Physics

“…However, digital and analogue quantum computations and quantum simulations have also been proposed for studies of lattice gauge theories of increasing complexity on different platforms [46,81,91,92,93,94,95,96,97,98,99,100], implementing or proposing paths to implement Feynman's seminal idea on NISQ era devices [101,102]. The interplay between tensor network simulations and real quantum computation and simulation will likely lead the development of the field in the next years [103,104].…”

Gluon Quasi Particles and the CGC Density Matrix

“…where xh (1) is the linearly polarized gluon distribution. Thus in general the Weizsäcker-Williams field correlator contains both longitudinal and transverse components, with the transverse component proportional to xG (1) − xh (1) .…”

“…To show this explicitly consider the eigenvalues of xG ij W W (x, k). Those are (xG (1) ± xh (1) )/2. At large momentum one can consider small r in the integrals (42) and (43).…”

“…The saturation corrections discussed in the previous section have a strong effect on the "dispersion relation" at low momenta. Beyond the dilute limit xG (1) dominates over xh (1) at k < Q s , so that both eigenvalues M± behave as xG (1) ∝ ln Q s /k in the infrared. This is a well known effect where the infrared 1/k 2 behavior of the TMD which formally leads to a power like infrared divergence in the produced particle spectrum is tamed by the saturation corrections and becomes logarithmic.…”

“…Recently there has been an increased interest in incorporating the concepts and methods of quantum information theory into nuclear and particle physics [1]. In particular various aspects of entanglement in application to hadronic collisions have been considered in [2][3][4][5][6][7][8].…”