Log in

Relevant bibliographies by topics / QED / Journal articles

To see the other types of publications on this topic, follow the link: QED.

Journal articles on the topic 'QED'

Author: Grafiati

Published: 4 June 2021

Last updated: 30 July 2024

Create a spot-on reference in APA, MLA, Chicago, Harvard, and other styles

Select a source type:

Consult the top 50 journal articles for your research on the topic 'QED.'

Next to every source in the list of references, there is an 'Add to bibliography' button. Press on it, and we will generate automatically the bibliographic reference to the chosen work in the citation style you need: APA, MLA, Harvard, Chicago, Vancouver, etc.

You can also download the full text of the academic publication as pdf and read online its abstract whenever available in the metadata.

Browse journal articles on a wide variety of disciplines and organise your bibliography correctly.

1

Bussone, Andrea, Michele Della Morte, and Tadeusz Janowski. "Electromagnetic corrections to the hadronic vacuum polarization of the photon within QEDL and QEDM." EPJ Web of Conferences 175 (2018): 06005. http://dx.doi.org/10.1051/epjconf/201817506005.

Full text

Abstract:

We compute the leading QED corrections to the hadronic vacuum polarization (HVP) of the photon, relevant for the determination of leptonic anomalous magnetic moments, al. We work in the electroquenched approximation and use dynamical QCD configurations generated by the CLS initiative with two degenerate flavors of nonperturbatively O(a)-improved Wilson fermions. We consider QEDL and QEDM to deal with the finite-volume zero modes. We compare results for the Wilson loops with exact analytical determinations. In addition we make sure that the volumes and photon masses used in QEDM are such that the correct dispersion relation is reproduced by the energy levels extracted from the charged pions two-point functions. Finally we compare results for pion masses and the HVP between QEDL and QEDM. For the vacuum polarization, corrections with respect to the pure QCD case, at fixed pion masses, turn out to be at the percent level.

APA, Harvard, Vancouver, ISO, and other styles

2

Risch, Andreas, and Hartmut Wittig. "Towards leading isospin breaking effects in mesonic masses with O(a) improved Wilson fermions." EPJ Web of Conferences 175 (2018): 14019. http://dx.doi.org/10.1051/epjconf/201817514019.

Full text

Abstract:

We present an exploratory study of leading isospin breaking effects in mesonic masses using O(a) improved Wilson fermions. Isospin symmetry is explicitly broken by distinct masses and electric charges of the up and down quarks. In order to be able to make use of existing isosymmetric QCD gauge ensembles we apply reweighting techniques. The path integral describing QCD+QED is expanded perturbatively in powers of the light quark’ mass deviations and the electromagnetic coupling. We employ QEDL as a finite volume formulation of QED.

APA, Harvard, Vancouver, ISO, and other styles

3

Wong, Cheuk-Yin. "QED Mesons, the QED Neutron, and the Dark Matter." EPJ Web of Conferences 259 (2022): 13016. http://dx.doi.org/10.1051/epjconf/202225913016.

Full text

Abstract:

Schwinger’s boson solution for massless fermions in QED in 1+1D has been applied and generalized to quarks interacting in QED and QCD interactions, leading to stable and confined open-string QED and QCD boson excitations of the quark-QCD-QED system in 1+1D. Just as the open-string QCD excitations in 1+1D can be the idealization of QCD mesons with a flux tube in 3+1D, so the open-string QED excitations in 1+1D may likewise be the idealization of QED mesons with masses in the tens of MeV region, corresponding possibly to the anomalous X17 and E38 particles observed recently. A further search for bound states of quarks interacting in the QED interaction alone leads to the examination on the stability of the QED neutron, consisting of two d quarks and one u quark. Theoretically, the QED neutron has been found to be stable and estimated to have a mass of 44.5 MeV, whereas the analogous QED proton is unstable, leading to a long-lived QED neutron that may be a good candidate for the dark matter.

APA, Harvard, Vancouver, ISO, and other styles

4

Wong, Cheuk-Yin. "QED Meson Description of the Anomalous Particles at ∼17 and ∼38 MeV." Universe 10, no. 4 (April 7, 2024): 173. http://dx.doi.org/10.3390/universe10040173.

Full text

Abstract:

The Schwinger confinement mechanism stipulates that a massless fermion and a massless antifermion are confined as a massive boson when they interact in the Abelian QED interaction in (1+1)D.If we approximate light quarks as massless and apply the Schwinger confinement mechanism to quarks, we can infer that a light quark and a light antiquark interacting in the Abelian QED interaction are confined as a QED meson in (1+1)D. Similarly, a light quark and a light antiquark interacting in the QCD interaction in the quasi-Abelian approximation will be confined as a QCD meson in (1+1)D. The QED and QCD mesons in (1+1)D can represent physical mesons in (3+1)D when the flux tube radius is properly taken into account. Such a theory leads to a reasonable description of the masses of π0,η, and η′, and its extrapolation to the unknown QED sector yields an isoscalar QED meson at about 17 MeV and an isovector QED meson at about 38 MeV. The observations of the anomalous soft photons, the hypothetical X17 particle, and the hypothetical E38 particle bear promising evidence for the possible existence of the QED mesons. Pending further confirmation, they hold important implications on the properties on the quarks and their interactions.

APA, Harvard, Vancouver, ISO, and other styles

5

Yam, Philip. "QED for QCD." Scientific American 269, no. 1 (July 1993): 23–24. http://dx.doi.org/10.1038/scientificamerican0793-23.

Full text

APA, Harvard, Vancouver, ISO, and other styles

6

SHI, SONG, WEI-MIN SUN, and HONG-SHI ZONG. "CHIRAL ANOMALY OF MASSLESS FERMION AT FINITE TEMPERATURE AND CHEMICAL POTENTIAL." Modern Physics Letters A 28, no. 06 (February 22, 2013): 1350006. http://dx.doi.org/10.1142/s0217732313500065.

Full text

Abstract:

In this paper, using the imaginary-time temperature field theory, we discuss the possible modification of chiral anomaly of a massless fermion in (3+1)-dimensional QED (QED4) when the temperature and chemical potential effects are included. It is found that the chiral anomaly is independent of the temperature and chemical potential. Meanwhile, we also introduce the chemical potential corresponding to chiral charge, and find that it will induce a Chern–Simons-like term, which has similar C transformation properties (and opposite P transformation property) to the corresponding Chern–Simons term in (2+1)-dimensional QED (QED3). More importantly, we find that when the chemical potential corresponding to the fermion number is space-dependent, it will induce an extra anomaly term. It is expected that this can yield new physical effects.

APA, Harvard, Vancouver, ISO, and other styles

7

Westin, Alex, Waseem Kamleh, Ross Young, James Zanotti, Roger Horsley, Yoshifumi Nakamura, Holger Perlt, Paul Rakow, Gerrit Schierholz, and Hinnerk Stüben. "Anomalous magnetic moment of the muon with dynamical QCD+QED." EPJ Web of Conferences 245 (2020): 06035. http://dx.doi.org/10.1051/epjconf/202024506035.

Full text

Abstract:

There exists a long standing discrepancy of around 3.5σ between experimental measurements and standard model calculations of the magnetic moment of the muon. Current experiments aim to reduce the experimental uncertainty by a factor of 4, and Standard Model calculations must also be improved by a similar factor. The largest uncertainty in the Standard Model calculation comes from the QCD contribution, in particular the leading order hadronic vacuum polarisation (HVP). To calculate the HVP contribution, we use lattice gauge theory, which allows us to study QCD at low energies. In order to better understand this quantity, we investigate the effect of QED corrections to the leading order HVP term by including QED in our lattice calculations, and investigate flavour breaking effects. This is done using fully dynamical QCD+QED gauge configurations generated by the QCDSF collaboration and a novel method of quark tuning.

APA, Harvard, Vancouver, ISO, and other styles

8

WARD, B. F. L., C. GLOSSER, S. JADACH, and S. A. YOST. "THRESHOLD CORRECTIONS IN PRECISION LHC PHYSICS: QED⊗QCD." International Journal of Modern Physics A 20, no. 16 (June 30, 2005): 3735–38. http://dx.doi.org/10.1142/s0217751x05027461.

Full text

Abstract:

With an eye toward LHC processes in which theoretical precisions of 1% are desired, we introduce the theory of the simultaneous YFS resummation of QED and QCD to compute the size of the expected resummed soft radiative threshold effects in precision studies of heavy particle production at the LHC. Our results show that both QED and QCD soft threshold effects must be controlled to be on the conservative side to achieve such precision goals.

APA, Harvard, Vancouver, ISO, and other styles

9

Palmer, C. D., and M. E. Carrington. "A general expression for symmetry factors of Feynman diagrams." Canadian Journal of Physics 80, no. 8 (August 1, 2002): 847–54. http://dx.doi.org/10.1139/p02-006.

Full text

Abstract:

The calculation of the symmetry factor corresponding to a given Feynman diagram is well known to be a tedious problem. We have derived a simple formula for these symmetry factors. Our formula works for any diagram in scalar theory (ϕ3 and ϕ4 interactions), spinor QED, scalar QED, or QCD. PACS Nos.: 11.10-z, 11.15-q, 11.15Bt

APA, Harvard, Vancouver, ISO, and other styles

10

FRY, M. P. "FERMION DETERMINANTS." International Journal of Modern Physics A 17, no. 06n07 (March 20, 2002): 936–45. http://dx.doi.org/10.1142/s0217751x02010339.

Full text

Abstract:

The current status of bounds on and limits of fermion determinants in two, three and four dimensions in QED and QCD is reviewed. A new lower bound on the two-dimensional QED determinant is derived. An outline of the demonstration of the continuity of this determinant at zero mass when the background magnetic field flux is zero is also given.

APA, Harvard, Vancouver, ISO, and other styles

11

Jeong, Eue-Jin. "QCD QED Potentials, Quark Confinement." International Journal of Fundamental Physical Sciences 12, no. 3 (September 17, 2022): 29–34. http://dx.doi.org/10.14331/ijfps.2022.330153.

Full text

Abstract:

One of the enduring puzzles in high energy particle physics is why quarks do not exist independently ‎despite their existence inside the hadron as quarks have never been found in isolation. This problem may ‎be solved by formulating a QCD potential for the entire range of interaction distances of the quarks. The ‎mystery could be related to the fundamental origin of the mass of elementary particles despite the success ‎of the quantum field theories to the highest level of accuracy. The renormalization program is an essential ‎part of the calculation of the scattering amplitudes, where the infinities of the calculated masses of the ‎elementary particles are subtracted for the progressive calculation of the higher-order perturbative terms. ‎The mathematical structure of the mass term from quantum field theories expressed in the form of infinities ‎suggests that there may exist a finite dynamical mass in the limit when the input mass parameter ‎approaches zero. The Lagrangian recovers symmetry at the same time as the input mass becomes zero, ‎whereas the self-energy diagrams acquire a finite dynamical mass in the 4-dimensional space when the ‎dimensional regularization method of renormalization is utilized. We report a new finding that using the ‎mathematical expression of the self-energy(mass) for photons and gluons calculated from this method, the ‎complex form of the QCD and QED interaction potentials can be obtained by replacing the fixed ‎interaction mediating particle’s mass and coupling constants in Yukawa potential with the scale-‎dependent running coupling constant and the corresponding dynamical mass. The derived QCD QED ‎potentials predict the behavior of the related elementary particles exactly as verified by experimental ‎observation.‎

APA, Harvard, Vancouver, ISO, and other styles

12

GROZIN, ANDREY. "DECOUPLING IN QED AND QCD." International Journal of Modern Physics A 28, no. 05n06 (March 10, 2013): 1350015. http://dx.doi.org/10.1142/s0217751x13500152.

Full text

APA, Harvard, Vancouver, ISO, and other styles

13

Bacchetta, Alessandro, and Miguel G. Echevarria. "QCD×QED evolution of TMDs." Physics Letters B 788 (January 2019): 280–87. http://dx.doi.org/10.1016/j.physletb.2018.11.019.

Full text

APA, Harvard, Vancouver, ISO, and other styles

14

GASSER, J., V. LYUBOVITSKIJ, and A. RUSETSKY. "Hadronic atoms in QCD+QED." Physics Reports 456, no. 5-6 (February 2008): 167–251. http://dx.doi.org/10.1016/j.physrep.2007.09.006.

Full text

APA, Harvard, Vancouver, ISO, and other styles

15

Minkowski, Peter. "Geometrodynamics and charge-like unification: On the vanishing of C, CP violation in QCD, in the limit GF → 0." International Journal of Modern Physics A 33, no. 31 (November 10, 2018): 1844008. http://dx.doi.org/10.1142/s0217751x18440086.

Full text

APA, Harvard, Vancouver, ISO, and other styles

16

Metayer, Simon, and Sofian Teber. "Critical Properties of Three-Dimensional Many-Flavor QEDs." Symmetry 15, no. 9 (September 21, 2023): 1806. http://dx.doi.org/10.3390/sym15091806.

Full text

Abstract:

We review several variants of three-dimensional quantum electrodynamics (QED3) with Nf fermion (or boson) flavors, including fermionic (or spinorial) QED3, bosonic (or scalar) QED3, N = 1 supersymmetric QED and also models of reduced QED (supersymmetric or not). We begin with an introduction to these models and their flow to a stable infra-red fixed point in the large-Nf limit. We then present detailed state-of-the-art computations of the critical exponents of these models within the dimensional regularization (and reduction) scheme(s), at the next-to-leading order in the 1/Nf expansion and in an arbitrary covariant gauge. We finally discuss dynamical (matter) mass generation and the current status of our understanding of the phase structure of these models.

APA, Harvard, Vancouver, ISO, and other styles

17

Grozin, Andrey. "Effective Field Theories." Particles 3, no. 2 (March 31, 2020): 245–71. http://dx.doi.org/10.3390/particles3020020.

Full text

Abstract:

This paper represents a pedagogical introduction to low-energy effective field theories. In some of them, heavy particles are “integrated out” (a typical example—the Heisenberg–Euler EFT); in some, heavy particles remain but some of their degrees of freedom are “integrated out” (Bloch–Nordsieck EFT). A large part of these lectures is, technically, in the framework of QED. QCD examples, namely decoupling of heavy flavors and HQET, are discussed only briefly. However, effective field theories of QCD are very similar to the QED case, and there are just some small technical complications: more diagrams, color factors, etc. The method of regions provides an alternative view at low-energy effective theories; this is also briefly introduced.

APA, Harvard, Vancouver, ISO, and other styles

18

Hansen, Martin, Biagio Lucini, Agostino Patella, and Nazario Tantalo. "Simulations of QCD and QED with C* boundary conditions." EPJ Web of Conferences 175 (2018): 09001. http://dx.doi.org/10.1051/epjconf/201817509001.

Full text

Abstract:

We present exploratory results from dynamical simulations of QCD in isolation, as well as QCD coupled to QED, with C* boundary conditions. In finite volume, the use of C* boundary conditions allows for a gauge invariant and local formulation of QED without zero modes. In particular we show that the simulations reproduce known results and that masses of charged mesons can be extracted in a completely gauge invariant way. For the simulations we use a modified version of the HiRep code. The primary features of the simulation code are presented and we discuss some details regarding the implementation of C* boundary conditions and the simulated lattice action. Preprint: CP3-Origins-2017-046 DNRF90, CERN-TH-2017-214

APA, Harvard, Vancouver, ISO, and other styles

19

NI, GUANG-JIONG, GUO-HONG YANG, RONG-TANG FU, and HAIBIN WANG. "RUNNING COUPLING CONSTANTS OF FERMIONS WITH MASSES IN QUANTUM ELECTRODYNAMICS AND QUANTUM CHROMODYNAMICS." International Journal of Modern Physics A 16, no. 16 (June 30, 2001): 2873–94. http://dx.doi.org/10.1142/s0217751x01001756.

Full text

Abstract:

Based on a simple but effective regularization-renormalization method (RRM), the running coupling constants (RCC) of fermions with masses in quantum electrodynamics (QED) and quantum chromodynamics (QCD) are calculated by renormalization group equation (RGE). Starting at Q=0 (Q being the momentum transfer), the RCC in QED increases with the increase of Q whereas the RCCs for different flavors of quarks with masses in QCD are different and they increase with the decrease of Q to reach a maximum at low Q for each flavor of quark and then decreases to zero at Q→0. Thus a constraint on the mass of light quarks, the hadronization energy scale of quark–antiquark pairs are derived.

APA, Harvard, Vancouver, ISO, and other styles

20

Castelo Ferreira, P., and J. Dias de Deus. "QCD corrections to QED vacuum polarization." European Physical Journal C 54, no. 4 (March 5, 2008): 539–45. http://dx.doi.org/10.1140/epjc/s10052-008-0556-z.

Full text

APA, Harvard, Vancouver, ISO, and other styles

21

Cartlidge, Edwin. "Lattice QCD: more difficult than QED." Physics World 17, no. 11 (November 2004): 12–13. http://dx.doi.org/10.1088/2058-7058/17/11/16.

Full text

APA, Harvard, Vancouver, ISO, and other styles

22

GRANDOU, T. "A REMARK ON THE HIGH TEMPERATURE LIMIT OF QCD." Modern Physics Letters A 25, no. 24 (August 10, 2010): 2099–103. http://dx.doi.org/10.1142/s0217732310033451.

Full text

APA, Harvard, Vancouver, ISO, and other styles

23

Mottaghizadeh, Marzieh, Parvin Eslami, and Fatemeh Taghavi-Shahri. "Decoupling the NLO-coupled QED⊗QCD, DGLAP evolution equations, using Laplace transform method." International Journal of Modern Physics A 32, no. 14 (April 18, 2017): 1750065. http://dx.doi.org/10.1142/s0217751x17500658.

Full text

Abstract:

We analytically solved the QED[Formula: see text]QCD-coupled DGLAP evolution equations at leading order (LO) quantum electrodynamics (QED) and next-to-leading order (NLO) quantum chromodynamics (QCD) approximations, using the Laplace transform method and then computed the proton structure function in terms of the unpolarized parton distribution functions. Our analytical solutions for parton densities are in good agreement with those from CT14QED [Formula: see text] (Ref. 6) global parametrizations and APFEL (A PDF Evolution Library) [Formula: see text] (Ref. 4). We also compared the proton structure function, [Formula: see text], with the experimental data released by the ZEUS and H1 collaborations at HERA. There is a nice agreement between them in the range of low and high [Formula: see text] and [Formula: see text].

APA, Harvard, Vancouver, ISO, and other styles

24

Stumpf, H., and W. Pfister. "Resolution of constraints and gauge equivalence in algebraic Schrödinger representation of quantum electrodynamics." Zeitschrift für Naturforschung A 51, no. 10-11 (November 1, 1996): 1045–66. http://dx.doi.org/10.1515/zna-1996-10-1101.

Full text

Abstract:

Abstract The algebraic formalism of QED is expounded in order to demonstrate both the resolution of constraints and to verify gauge equivalence between temporal gauge and Coulomb gauge on the quantum level. In the algebraic approach energy eigenstates of QED in temporal gauge are represented in an algebraic GNS basis. The corresponding Hilbert space is mapped into a functional space of generating functional states. The image of the QED-Heisenberg dynamics becomes a functional energy equation for these states. In the same manner the Gauß constraint is mapped into functional space. By suitable transformations the functional image of the Coulomb forces is recovered in temporal gauge. The equivalence of this result with the functional version of QED in Coulomb gauge is demonstrated. The meaning of the various transformations and their relations are illustrated for the case of harmonic oscillators. If applied to QCD this method allows an exact derivation of effective color "Coulomb" forces, in addition it implies a clear conception for the incorporation of various algebraic representations into the formal Heisenberg dynamics and establishes the algebraic "Schrödinger" equation for quantum fields in functional space.

APA, Harvard, Vancouver, ISO, and other styles

25

Hancocks OBE, Stephen. "QED." British Dental Journal 233, no. 6 (September 23, 2022): 437. http://dx.doi.org/10.1038/s41415-022-5048-2.

Full text

APA, Harvard, Vancouver, ISO, and other styles

26

Feynman, Richard, and Will Hughes. "QED." American Journal of Physics 54, no. 8 (August 1986): 766–67. http://dx.doi.org/10.1119/1.14435.

Full text

APA, Harvard, Vancouver, ISO, and other styles

27

Wright, Alison. "QED." Nature Materials 9, S1 (May 2010): S9. http://dx.doi.org/10.1038/nmat2643.

Full text

APA, Harvard, Vancouver, ISO, and other styles

28

PAGE, PHILIP R. "(FIELD) SYMMETRIZATION SELECTION RULES." International Journal of Modern Physics A 16, supp01c (September 2001): 1216–18. http://dx.doi.org/10.1142/s0217751x01009351.

Full text

Abstract:

QCD and QED exhibit an infinite set of three-point Green's functions that contain only OZI rule violating contributions, and (for QCD) are subleading in the large N c expansion. We prove that the QCD amplitude for a neutral hybrid 1-+ exotic current to create ηπ0 only comes from OZI rule violation contributions under certain conditions, and is subleading in N c .

APA, Harvard, Vancouver, ISO, and other styles

29

FIELD, J. H. "FERMION MASS SINGULARITIES IN QED AND QCD AND THE MEANING OF THE KINOSHITA-LEE-NAUENBERG THEOREM." Modern Physics Letters A 11, no. 37 (December 7, 1996): 2921–31. http://dx.doi.org/10.1142/s0217732396002897.

Full text

Abstract:

An analysis is presented of radiative corrections due to fermion vacuum polarization for the process e−μ−→e−μ− and the full O(α2) final state QED radiative correction to [Formula: see text]. It is demonstrated that in both cases, the corrections contain next-to-leading logarithmic terms of the form α2 ln [Formula: see text]where Q is the large external scale and m is the fermion mass. These radiative corrections are infinite in the massless limit for any nonvanishing value of α. The role of Landau singularities and the relation of the above results to the Kinoshita-Lee-Nauenberg (KLN) theorem are discussed. Similar considerations also apply to the fermion sector of QCD where m is the quark mass. Thus contrary to many statements to be found in the literature no finite massless version of either QED or QCD can exist.

APA, Harvard, Vancouver, ISO, and other styles

30

Sun, Weimin. "Physical angular momentum separation for QED." Modern Physics Letters A 32, no. 11 (April 7, 2017): 1750063. http://dx.doi.org/10.1142/s0217732317500638.

Full text

Abstract:

We study the non-uniqueness problem of the gauge-invariant angular momentum separation for the case of QED, which stems from the recent controversy concerning the proper definitions of the orbital angular momentum and spin operator of the individual parts of a gauge field system. For the free quantum electrodynamics without matter, we show that the basic requirement of Euclidean symmetry selects a unique physical angular momentum separation scheme from the multitude of the possible angular momentum separation schemes constructed using the various gauge-invariant extensions (GIEs). Based on these results, we propose a set of natural angular momentum separation schemes for the case of interacting QED by invoking the formalism of asymptotic fields. Some perspectives on such a problem for the case of QCD are briefly discussed.

APA, Harvard, Vancouver, ISO, and other styles

31

Campos, Isabel, Patrick Fritzsch, Martin Hansen, Marina Krstić Marinković, Agostino Patella, Alberto Ramos, and Nazario Tantalo. "openQ*D simulation code for QCD+QED." EPJ Web of Conferences 175 (2018): 09005. http://dx.doi.org/10.1051/epjconf/201817509005.

Full text

Abstract:

The openQ*D code for the simulation of QCD+QED with C* boundary conditions is presented. This code is based on openQCD-1.6, from which it inherits the core features that ensure its efficiency: the locally-deflated SAP-preconditioned GCR solver, the twisted-mass frequency splitting of the fermion action, the multilevel integrator, the 4th order OMF integrator, the SSE/AVX intrinsics, etc. The photon field is treated as fully dynamical and C* boundary conditions can be chosen in the spatial directions. We discuss the main features of openQ*D, and we show basic test results and performance analysis. An alpha version of this code is publicly available and can be downloaded from http://rcstar.web.cern.ch/.

APA, Harvard, Vancouver, ISO, and other styles

32

GLOSSER, C., S. JADACH, B. F. L. WARD, and S. A. YOST. "QED ⊗ QCD THRESHOLD CORRECTIONS AT THE LHC." Modern Physics Letters A 19, no. 28 (September 14, 2004): 2113–19. http://dx.doi.org/10.1142/s0217732304015397.

Full text

Abstract:

We use the theory of YFS resummation to compute the size of the expected resummed soft radiative threshold effects in precision studies of heavy particle production at the LHC, where accuracies of 1% are desired in some processes. We find that the soft QED threshold effects are at the level of 0.3% whereas the soft QCD threshold effects enter at the level of 20% and hence both must be controlled to be on the conservative side to achieve such goals.

APA, Harvard, Vancouver, ISO, and other styles

33

Greiner, Walter, and Stefan Schramm. "Resource Letter QEDV-1: The QED vacuum." American Journal of Physics 76, no. 6 (June 2008): 509–18. http://dx.doi.org/10.1119/1.2820395.

Full text

APA, Harvard, Vancouver, ISO, and other styles

34

Kapusta, J., and T. Toimela. "Friedel oscillations in relativistic QED and QCD." Physical Review D 37, no. 12 (June 15, 1988): 3731–36. http://dx.doi.org/10.1103/physrevd.37.3731.

Full text

APA, Harvard, Vancouver, ISO, and other styles

35

KHOZE, V. A., A. I. LEBEDEV, and J. A. VAZDIK. "QCD COHERENCE IN DIRECT COMPTON SCATTERING." Modern Physics Letters A 09, no. 18 (June 14, 1994): 1665–71. http://dx.doi.org/10.1142/s0217732394001507.

Full text

Abstract:

The color coherence effects are studied for direct processes of γp interactions at high energies using PYTHIA Monte-Carlo simulation and perturbative QCD approach. Sub-processes of QED and QCD Compton scattering on quarks leading to jet topology of photoproduction events are considered. It is shown that the coherence leads to drag phenomenon in the interjet region.

APA, Harvard, Vancouver, ISO, and other styles

36

KE, HONG-WEI, ZUO LI, JING-LING CHEN, YI-BING DING, and XUE-QIAN LI. "SYMMETRY OF DIRAC EQUATION AND CORRESPONDING PHENOMENOLOGY." International Journal of Modern Physics A 25, no. 06 (March 10, 2010): 1123–34. http://dx.doi.org/10.1142/s0217751x1004783x.

Full text

Abstract:

It has been suggested that the high symmetries in the Schrödinger equation with the Coulomb or harmonic oscillator potentials may remain in the corresponding relativistic Dirac equation. If the principle is correct, in the Dirac equation the potential should have a form as [Formula: see text] where V(r) is [Formula: see text] for hydrogen atom and κr2 for harmonic oscillator. However, in the case of hydrogen atom, by this combination the spin–orbit coupling term would not exist and it is inconsistent with the observational spectra of hydrogen atom, so that the symmetry of SO(4) must reduce into SU(2). The governing mechanisms QED and QCD which induce potential are vector-like theories, so at the leading order only vector potential exists. However, the higher-order effects may cause a scalar fraction. In this work, we show that for QED, the symmetry restoration is very small and some discussions on the symmetry breaking are made. At the end, we briefly discuss the QCD case and indicate that the situation for QCD is much more complicated and interesting.

APA, Harvard, Vancouver, ISO, and other styles

37

Anikin, Igor V. "On ξ-Process for DVCS-Amplitude." Symmetry 12, no. 12 (December 3, 2020): 1996. http://dx.doi.org/10.3390/sym12121996.

Full text

Abstract:

In this note, we demonstrate in detail the ξ-process implementation applied to the deeply virtual Compton scattering amplitude to ensure both the QCD and QED gauge invariance. The presented details are also important for the understanding of the contour gauge used in different processes.

APA, Harvard, Vancouver, ISO, and other styles

38

Fabiano, Nicola. "Corrections to propagators of quantum electrodynamics." Vojnotehnicki glasnik 69, no. 4 (2021): 930–40. http://dx.doi.org/10.5937/vojtehg69-30604.

Full text

Abstract:

Introduction/purpose: The problem of quantum corrections to propagators in Quantum Electrodynamics (QED) is discussed. Methods: The Dyson-Schwinger equation is employed for correcting propagators in QED. Results: The observable quantities in QED are finite. Conclusions: QED divergencies can be avoided by redefining physical quantities in a suitable manner.

APA, Harvard, Vancouver, ISO, and other styles

39

Wilson, James H. "Completing Dirac’s work. The Dirac electron is a 2D hologram." Physics Essays 36, no. 4 (December 23, 2023): 450–58. http://dx.doi.org/10.4006/0836-1398-36.4.450.

Full text

Abstract:

The QED-physical (QED-P) theory [J. H. Wilson, Phys. Essays 35, 5 (2022)] is actually the theory Dirac sought in 1962 in his attempt to predict the muon as an “extensible model of the electron.” Recently, Lerche attempted to produce a classical solution to Dirac’s equation for the radial motion of an extensible, basically classical, model of the electron. Both Dirac and Lerche proceeded in the wrong, classical direction in this effort. The QED-P center of charge (CoC) position operator is derived directly from the Dirac equation (DE) CoC velocity operator, cα with no ad hoc assumptions. QED-P was integrated with QED into a single theory, and that integration is proved by the highly accurate estimates of QED that are dependent on the DE velocity operator cα. Both QED and QED-P are based directly on the same Dirac Equation (DE) four current c(α,I) that QED couples with an external electromagnetic field. QED uses covariant perturbation theory to produce highly accurate results, except for the electron selfenergy, which is infinite. The DE velocity operator, cα, is the spatial part of the free electron four current, and has highly unusual properties compared to classical velocity vectors. QED could not produce highly accurate answers without the 4 × 4 complex matrix cα as the electron CoC “velocity” operator. QED-P simply integrates the same Dirac equation four current used so successfully in QED, and produces the discrete internal spatial and time coordinate operators (ISaTCOs) to give the electron field’s internal structure a very specific, but highly, nonclassical geometric description, with no ad hoc assumptions. QED and QED-P are complementary theories, and both are proven to be true by the accurate results of QED. The physical interpretation of QED-P is discussed in this paper as a two-dimensional, rapidly vibrating “point” charge, that is always located on a 2D CoC sphere in the electron rest frame, oscillating rapidly through eight eigenvalues with an ISaTCO period of ∼10−22 s. The fact that the CoC’s eight ISaTCO spatial eigenvectors are always are located on a 2D shell encompassing the electron’s 3D “space” inside the CoC’s 2D shell is a direct consequence of the DE, and nothing else. In this paper, it is shown that the “discrete” ISaTCOs produce a one dimensional, discrete quantum harmonic oscillator with its ISaTCOs always located on a 2D CoC shell. The CoC shell is an “2D hologram” emerging from a 3D volume inside the 2D CoC shell with a vibrational electronic clock” producing an internal phase that is propagated throughout space/time. The QED-P point electron charge rotates 720° to complete one internal electron discrete period. The electron’s spin and magnetic moment [J. H. Wilson, Phys. Essays 29, 402 (2016); ibid. 31(1), 59‐67 (2018); ibid. 34, 17 (2021)] are generated by the CoC ISaTCO in QED-P, and there is no need for “intrinsic” properties. The QED-P electron properties described above d are far different than the standard model’s very small point particle with intrinsic properties of spin and magnetic moment.

APA, Harvard, Vancouver, ISO, and other styles

40

Fabiano, Nicola. "Quantum electrodynamics divergencies." Vojnotehnicki glasnik 69, no. 3 (2021): 656–75. http://dx.doi.org/10.5937/vojtehg69-30366.

Full text

Abstract:

Introduction/purpose: The problem of divergencies in Quantum Electrodynamics (QED) is discussed. Methods: The renormalisation group method is employed for dealing with infinities in QED. Results: The integrals in QED giving physical observables are finite. Conclusions: The divergencies in QED can be treated in a consistent way providing mathematical rigorous results.

APA, Harvard, Vancouver, ISO, and other styles

41

Wilson, James H. "The QED-physical theory of electron spin and quantum entanglement." Physics Essays 35, no. 1 (November 1, 2022): 5–14. http://dx.doi.org/10.4006/0836-1398-35.1.5.

Full text

Abstract:

The QED-Physical (QED-P) theory described in four previous papers [J. H. Wilson, Phys. Essays 28, 1 (2015); 29, 402 (2016); 31, 59 (2018); 34, 17 (2021)] is combined with QED into a single theory in this paper, since both are based on the same Dirac Equation four current c(α,I). QED couples this four-vector with an external electromagnetic (EM) field and uses covariant perturbation theory to produce results that are very accurate computationally [M. L. Eides et al., Phys. Rep. 342, 63 (2001)], except for the electron self-energy, which is infinite. The reason for QED’s accuracy is its Dirac equation velocity operator, cα, with highly unusual properties compared to classical velocity vectors. QED could not produce highly accurate answers without the 4 × 4 complex matrix cα as the electron “velocity operator.” QED-P starts with the same Dirac Equation four current used so successfully in QED, and the discrete internal spatial and time coordinate operators (ISaTCOs) are derived in QED-P to give the electron internal structure a very specific, but highly, nonclassical geometric description with no ad hoc assumptions. The QED/QED-physical (QED-P) unification theorem is stated and proved in Sec. VII. However, one should ask what new physical measurements are predicted by QED-P that are not determined by the very accurate QED? The answer is none yet, due to the very rapid fluctuation of the ISaTCOs with a period of ∼6.4 × 10−22 s. This induced electron field fluctuation is in addition to any vacuum fluctuation that exists without the electron field present. This paper presents a highly speculative, but testable, experiment, in which the ISaTCO rapid fluctuations may be confirmed indirectly as the physical basis of field quantum entanglement (QE). The electron’s ISaTCO produce a digital internal clock that’s locked out of phase with its entangled positron, and they communicate spin states at the phase speed of 2c2/vCoM. The communication of spin state information is instantaneous for vCoM = 0 but “slows down” to 4c at vCoM = 0.5c, still very fast.

APA, Harvard, Vancouver, ISO, and other styles

42

NASSIF, CLÁUDIO, and P. R. SILVA. "QUANTUM ELECTRODYNAMICS AND CHROMODYNAMICS TREATED THROUGH THOMPSON'S APPROACH." International Journal of Modern Physics A 21, no. 18 (July 20, 2006): 3809–24. http://dx.doi.org/10.1142/s0217751x06031508.

Full text

Abstract:

In this work we apply Thompson's method (of the dimensions and scales) to study some features of the Quantum Electrodynamics and Chromodynamics. This heuristic method can be considered as a simple and alternative way to the Renormalization Group approach and when applied to QED-Lagrangian is able to obtain in a first approximation both the running coupling constant behavior of α(μ) and the mass m(μ). The calculations are evaluated only at dc = 4, where dc is the upper critical dimension of the problem, so that we obtain the logarithmic behavior both for the coupling α and the excess of mass Δm on the energy scale μ. Although our results are well known in the vast literature of field theories, the advantage of Thompson's method, beyond its simplicity is that it is able to extract directly from QED-Lagrangian the physical (finite) behavior of α(μ) and m(μ), bypassing hard problems of divergences which normally appear in the conventional renormalization schemes applied to field theories like QED. Quantum Chromodynamics (QCD) is also treated by the present method in order to obtain the quark condensate value. Besides this, the method is also able to evaluate the vacuum pressure at the boundary of the nucleon. This is done by assumming a step function behavior for the running coupling constant of the QCD, which fits nicely to some quantities related to the strong interaction evaluated through the MIT-bag model.

APA, Harvard, Vancouver, ISO, and other styles

43

Huamani Chaviguri, Richard, and Fulgencio Villegas Silva. "Simetrías gauge local aplicadas a la física." Revista de Investigación de Física 14, no. 01 (July 15, 2011): 1–9. http://dx.doi.org/10.15381/rif.v14i01.8537.

Full text

Abstract:

En este trabajo damos una descripción sencilla acerca de las simetrías gauge locales tanto abeliana como no abeliana y sus posteriores aplicaciones fundamentales a la física que surgen para cada transformación gauge particular como son la electrodiámica cuántica, QED, Campo Leptónico y la cromodinámica cuántica, QCD.

APA, Harvard, Vancouver, ISO, and other styles

44

Cieri, Leandro, and German Sborlini. "Exploring QED Effects to Diphoton Production at Hadron Colliders." Symmetry 13, no. 6 (June 2, 2021): 994. http://dx.doi.org/10.3390/sym13060994.

Full text

Abstract:

In this article, we report phenomenological studies about the impact of O(α) corrections to diphoton production at hadron colliders. We explore the application of the Abelianized version of the qT-subtraction method to efficiently compute NLO QED contributions, taking advantage of the symmetries relating QCD and QED corrections. We analyze the experimental consequences due to the selection criteria and we find percent-level deviations for Mγγ>1TeV. An accurate description of the tail of the invariant mass distribution is very important for new physics searches which have the diphoton process as one of their main backgrounds. Moreover, we emphasize the importance of properly dealing with the observable photons by reproducing the experimental conditions applied to the event reconstruction.

APA, Harvard, Vancouver, ISO, and other styles

45

Liang, Yanqi, Mengze Qi, Anji Xu, and Ziwen Zhang. "QED effects exploration based on ultra-intensity lasers." Highlights in Science, Engineering and Technology 5 (July 7, 2022): 35–45. http://dx.doi.org/10.54097/hset.v5i.721.

Full text

Abstract:

With the development of the laser technology, the interaction between laser and matter is expected to enter the field of strong field QED, which has become as one of the hottest research directions. In this paper, we present the development of laser technology and the realization of ultra-intense ultra-short laser. Specifically, we demonstrate the progress of laser strong field QED and the laser-plasma interaction. Especially, the frontier progress of Laser-plasma QED, as well as its results of numerical simulation and the related QED process are demonstrated. Additionally, some relevant interesting strong field QED effects are also discussed. Besides, the frontier development of vacuum-related QED effects is evaluated, e.g., the vacuum birefringence. These results have important practical significance for some applications related to precision measurement, for example the optical clock. Moreover, they shed light on testing the basic theory of QED from a higher precision and guiding for new generation of laser development.

APA, Harvard, Vancouver, ISO, and other styles

46

KONDO, KEI-ICHI, and HAJIME NAKATANI. "DIMENSIONAL DEPENDENCE OF CHIRAL-SYMMETRY- BREAKING PHASE TRANSITION IN QUENCHED PLANAR QED." Modern Physics Letters A 04, no. 22 (October 30, 1989): 2155–66. http://dx.doi.org/10.1142/s0217732389002422.

Full text

Abstract:

We consider the critical behavior of the phase transition associated with the spontaneous breaking of chiral-symmetry in (QED) D, in the framework of the Schwinger-Dyson equation. Special attention is paid on the scaling law. While it is well known that quenched planar QED 4 obeys the Miransky scaling of the essential singularity type, our numerical calculations show that QED 5 and QED 6 do obey the mean-field type scaling, even in the quenched planar approximation. Thus the essential singularity type scaling in the cutoff QED is considered to be possible only when D=4 under the quenched planar approximation.

APA, Harvard, Vancouver, ISO, and other styles

47

Hedendahl, Daniel, Ingvar Lindgren, and Sten Salomonson. "Towards numerical implementation of the relativistically covariant many-body perturbation theoryThis paper was presented at the International Conference on Precision Physics of Simple Atomic Systems, held at University of Windsor, Windsor, Ontario, Canada on 21–26 July 2008." Canadian Journal of Physics 87, no. 7 (July 2009): 817–24. http://dx.doi.org/10.1139/p08-146.

Full text

Abstract:

The standard procedure for relativistic many-body perturbation theory (RMBPT) is not relativistically covariant, and the effects of retardation, virtual-electron-positron-pair, and radiative effects (self-energy, vacuum polarisation, and vertex correction) — the so-called QED effects — are left out. The energy contribution from the QED effects can be evaluated by the covariant evolution operator method, which has a structure that is similar to that of RMBPT, and it can serve as a merger between QED and RMBPT. The new procedure makes it, in principle, possible for the first time to evaluate QED effects together with correlation to high order. The procedure is now being implemented, and it has been shown that the effect of electron correlation on first-order QED for He-like neon dominates heavily over second-order QED effects.

APA, Harvard, Vancouver, ISO, and other styles

48

LEE, Kimyeong. "Beyond QED." Physics and High Technology 24, no. 5 (May 31, 2015): 14. http://dx.doi.org/10.3938/phit.24.024.

Full text

APA, Harvard, Vancouver, ISO, and other styles

49

Ford, C. "Magnetic QED." Journal of Physics A: Mathematical and Theoretical 41, no. 48 (October 21, 2008): 482001. http://dx.doi.org/10.1088/1751-8113/41/48/482001.

Full text

APA, Harvard, Vancouver, ISO, and other styles

50

Koberinski, Adam, and Chris Smeenk. "Q.E.D., QED." Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 71 (August 2020): 1–13. http://dx.doi.org/10.1016/j.shpsb.2020.03.003.

Full text

APA, Harvard, Vancouver, ISO, and other styles

We offer discounts on all premium plans for authors whose works are included in thematic literature selections. Contact us to get a unique promo code!