Defect Theory of Positronium and Nontrivial QED Relations

• URL: http://arxiv.org/abs/2107.05505v2
• Date: Mon, 6 Sep 2021 13:43:25 GMT
• Title: Defect Theory of Positronium and Nontrivial QED Relations
• Authors: David M. Jacobs
• Abstract summary: Theory of excited states of positronium is derived and some of its consequences are explored. It provides an accurate and economical, yet largely QED-independent, means to fit the positronium spectrum in order to predict and compare the outcome of experiments.
• Score: 0.0
• License: http://creativecommons.org/licenses/by/4.0/
• Abstract: An effective theory of the excited states of positronium is derived and some of its consequences are explored. At large physical separation, the binding of the electron and positron is assumed to be described completely by QED, whereas all short-ranged phenomena, including those within and beyond QED, can be accounted for with energy-dependent quantum defects. This theory has at least two practical applications. First, it provides an accurate and economical, yet largely QED-independent, means to fit the positronium spectrum in order to predict and compare the outcome of experiments. Second, matching the spectrum in this effective theory to that predicted by QED reveals nontrivial relationships that exist \emph{within} bound-state QED; some higher order contributions to the spectrum may be obtained from lower order contributions. These relations are verified up to order $m\alpha^{6}$, and predictions are made for the order $m\alpha^{7}$ and $m\alpha^{8}$ corrections. This theory and its extensions to other hydrogenic systems may provide a useful complement to bound-state QED.

Related papers

• Linear response theory for cavity QED materials [41.94295877935867]
  We derive closed formulas for various responses of both the cavity and the matter. We discover novel excitations in quantum magnets, where the cavity binds magnon pairs into localized states.
  arXiv  Detail & Related papers  (2024-06-17T18:00:01Z)
• Testing trajectory-based determinism via time probability distributions [44.99833362998488]
  Bohmian mechanics (BM) has inherited more predictive power than quantum mechanics (QM) We introduce a prescription for constructing a flight-time probability distribution within generic trajectory-equipped theories. We derive probability distributions that are unreachable by QM.
  arXiv  Detail & Related papers  (2024-04-15T11:36:38Z)
• Thermal masses and trapped-ion quantum spin models: a self-consistent approach to Yukawa-type interactions in the $λ\!φ^4$ model [44.99833362998488]
  A quantum simulation of magnetism in trapped-ion systems makes use of the crystal vibrations to mediate pairwise interactions between spins. These interactions can be accounted for by a long-wavelength relativistic theory, where the phonons are described by a coarse-grained Klein-Gordon field. We show that thermal effects, which can be controlled by laser cooling, can unveil this flow through the appearance of thermal masses in interacting QFTs.
  arXiv  Detail & Related papers  (2023-05-10T12:59:07Z)
• Complex-scaled ab initio QED approach to autoionizing states [0.0]
  Ab initio method based on a complex-scaling approach and aimed at a rigorous QED description of autoionizing states is worked out. The autoionizing-state binding energies are treated nonperturbatively in $alpha Z$ and include all the many-electron QED contributions up to the second order.
  arXiv  Detail & Related papers  (2022-10-03T09:11:26Z)
• Higher-order mean-field theory of chiral waveguide QED [0.0]
  Waveguide QED with cold atoms provides a potent platform for the study of non-equilibrium, many-body, and open-system quantum dynamics. We apply an improved mean-field theory based on higher-order cumulant expansions to describe the experimentally relevant, but theoretically elusive, regime of weak coupling. Our approach allows to quantify the trade-off between anti-bunching and output power in previously inaccessible parameter regimes.
  arXiv  Detail & Related papers  (2022-07-21T12:22:41Z)
• Excitation spectra of two correlated electrons in a quantum dot [0.0]
  Experimentally, excited states are found beyond the well-known lowest singlet- and triplet states. These states can be reproduced in an exact diagonalization calculation of a parabolic dot with moderate in-plane anisotropy.
  arXiv  Detail & Related papers  (2021-12-28T18:20:29Z)
• $\mathcal{P}$,$\mathcal{T}$-odd effects for RaOH molecule in the excited vibrational state [77.34726150561087]
  Triatomic molecule RaOH combines the advantages of laser-coolability and the spectrum with close opposite-parity doublets. We obtain the rovibrational wave functions of RaOH in the ground electronic state and excited vibrational state using the close-coupled equations derived from the adiabatic Hamiltonian.
  arXiv  Detail & Related papers  (2020-12-15T17:08:33Z)
• Fate of Lattice Gauge Theories Under Decoherence [0.0]
  We study the effect of decoherence on the quench dynamics of a lattice gauge theory. We introduce multiple quantum coherences in the context of gauge theories to quantify decoherence effects.
  arXiv  Detail & Related papers  (2020-09-16T18:00:01Z)
• Self-consistent M{\o}ller-Plesset Perturbation Theory For Excited States [0.0]
  We explore the possibility of correcting HF excited states using Moller-Plesset perturbation theory to the second order. Among various PT2 variants, we find that the restricted open-shell MP2 (ROMP2) gives excitation energies comparable to the best density functional theory results.
  arXiv  Detail & Related papers  (2020-08-25T01:48:39Z)
• Probing eigenstate thermalization in quantum simulators via fluctuation-dissipation relations [77.34726150561087]
  The eigenstate thermalization hypothesis (ETH) offers a universal mechanism for the approach to equilibrium of closed quantum many-body systems. Here, we propose a theory-independent route to probe the full ETH in quantum simulators by observing the emergence of fluctuation-dissipation relations. Our work presents a theory-independent way to characterize thermalization in quantum simulators and paves the way to quantum simulate condensed matter pump-probe experiments.
  arXiv  Detail & Related papers  (2020-07-20T18:00:02Z)
• Quantum decoherence by Coulomb interaction [58.720142291102135]
  We present an experimental study of the Coulomb-induced decoherence of free electrons in a superposition state in a biprism electron interferometer close to a semiconducting and metallic surface. The results will enable the determination and minimization of specific decoherence channels in the design of novel quantum instruments.
  arXiv  Detail & Related papers  (2020-01-17T04:11:44Z)

This list is automatically generated from the titles and abstracts of the papers in this site.

This site does not guarantee the quality of this site (including all information) and is not responsible for any consequences.