PROPERTIES OF SCALAR-QUARK SYSTEMS IN SU(3)c LATTICE QCD

We perform the first study for the bound states of colored scalar particles ϕ (“scalar quarks”) in terms of mass generation with quenched SU (3)c lattice QCD. We investigate the bound states of ϕ, ϕ†ϕ and ϕϕϕ (“scalar-quark hadrons”), as well as the bound states of ϕ and quarks ψ, i.e., ϕ†ψ, ψψϕ and ϕϕψ (“chimera hadrons”). All these new-type hadrons including ϕ have a large mass of several GeV due to large quantum corrections by gluons, even for zero bare scalar-quark mass mϕ = 0 at a−1 ~ 1 GeV . We find a similar mψ-dependence between ϕ†ψ and ϕϕψ, which indicates their similar structure due to the large mass of ϕ. From this study, we conjecture that all colored particles generally acquire a large effective mass due to dressed gluons.

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The theory of conditional invariance. I

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1968.0124 ◽

1968 ◽

Vol 305 (1482) ◽

pp. 405-427 ◽

Cited By ~ 1

Keyword(s):

Bound States ◽

General Relation ◽

Variable Parameter ◽

Geometric Invariance ◽

Hermitian Conjugate ◽

New Type ◽

Definition Of ◽

Conditional Invariance ◽

Conditional Constant ◽

The Continuum

In order to extend the use of group theoretical arguments to the problem of accidental degeneracy in quantum mechanics, a new type of constant of the motion, known as a conditional constant of the motion, is introduced. Such a quantity, instead of commuting with the Hamiltonian H for the system, satisfies the more general relation H A = A † H , where A † denotes the hermitian conjugate (adjoint) of the conditional constant of the motion A . This expression reduces, if A is hermitian, to the usual definition of a constant of the motion. Otherwise it defines a new type of invariance, and it is this which will be referred to as conditional invariance. A discussion of the difficulties arising from the lack of hermiticity of A , which is of course essential to its definition, is given. In particular it is shown, under fairly general conditions, that the process of introducing a variable parameter in the Hamiltonian enabling it to have simultaneous eigenfunctions with A , gives rise to an eigenvalue equation in this parameter with respect to which A may be chosen to be hermitian. Conditional invariance is contrasted with both dynamical and geometric invariance. It is found to be sometimes replaceable by either of the latter forms of invariance and for such, explicit conditions are given. Some applications of conditional invariance are discussed. These include a study of the crossing of potential energy curves, a new model of symmetry breaking, a possible means of calculating the exact number of bound states for certain potentials and conditions for the existence of bound states near to the continuum.

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Baryon-baryon bound states in strongly coupled lattice QCD

Physical Review D ◽

10.1103/physrevd.75.074503 ◽

2007 ◽

Vol 75 (7) ◽

Cited By ~ 10

Author(s):

Paulo A. Faria da Veiga ◽

Michael O’Carroll

Keyword(s):

Lattice Qcd ◽

Bound States ◽

Strongly Coupled

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Fracton phases of matter

International Journal of Modern Physics A ◽

10.1142/s0217751x20300033 ◽

2020 ◽

Vol 35 (06) ◽

pp. 2030003 ◽

Cited By ~ 18

Author(s):

Michael Pretko ◽

Xie Chen ◽

Yizhi You

Keyword(s):

Elasticity Theory ◽

Bound States ◽

Spin Liquids ◽

Exotic Particles ◽

The Past ◽

Condensed Matter Theory ◽

Open Questions ◽

Introductory Material ◽

Matter Theory ◽

New Type

Fractons are a new type of quasiparticle which are immobile in isolation, but can often move by forming bound states. Fractons are found in a variety of physical settings, such as spin liquids and elasticity theory, and exhibit unusual phenomenology, such as gravitational physics and localization. The past several years have seen a surge of interest in these exotic particles, which have come to the forefront of modern condensed matter theory. In this review, we provide a broad treatment of fractons, ranging from pedagogical introductory material to discussions of recent advances in the field. We begin by demonstrating how the fracton phenomenon naturally arises as a consequence of higher moment conservation laws, often accompanied by the emergence of tensor gauge theories. We then provide a survey of fracton phases in spin models, along with the various tools used to characterize them, such as the foliation framework. We discuss in detail the manifestation of fracton physics in elasticity theory, as well as the connections of fractons with localization and gravitation. Finally, we provide an overview of some recently proposed platforms for fracton physics, such as Majorana islands and hole-doped antiferromagnets. We conclude with some open questions and an outlook on the field.

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Bound state energy and wave function of tetraquark b̄b̄ud from lattice QCD potential

Modern Physics Letters A ◽

10.1142/s0217732319502201 ◽

2019 ◽

Vol 34 (27) ◽

pp. 1950220

Author(s):

F. Chezani Sharahi ◽

M. Monemzadeh ◽

A. Abdoli Arani

Keyword(s):

Wave Function ◽

Lattice Qcd ◽

Bound States ◽

State Energy ◽

Energy State ◽

Light Quark ◽

Bound State ◽

Bound State Energy ◽

Quark System ◽

Oppenheimer Approximation

In this study, the bound state energy of a four-quark system was analytically calculated as a two heavy–heavy anti-quarks [Formula: see text] and two light–light quarks [Formula: see text]. Tetraquark was assumed to be a bound state of two-body system consisting of two mesons, each containing a light quark and a heavy antiquark. Due to the presence of heavy mesons in the tetraquark, Born–Oppenheimer approximation was used to study its bound states. To assess the bounding energy, Schrödinger equation was solved using lattice QCD [Formula: see text] potential, having expanded the tetraquark potential [Formula: see text] up to 11th term. Binding energy state and wave function, however, were obtained in the scalar [Formula: see text] channel. Graphical results for wave functions obtained versus antiquark–antiquark distance [Formula: see text] confirmed the existence of the tetraquark [Formula: see text]. Analytical bound state energy obtained here was in good agreement with several numerical ones published in the literature, confirming the accuracy of the approach taken here.

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Lattice QCD Results and Prospects

International Journal of Modern Physics A ◽

10.1142/s0217751x03016549 ◽

2003 ◽

Vol 18 (supp01) ◽

pp. 1-26

Author(s):

Richard Kenway

Keyword(s):

Standard Model ◽

Lattice Qcd ◽

Strong Interaction ◽

Bound States ◽

Leading Edge ◽

Beyond The Standard Model ◽

Quark Masses ◽

The Standard Model ◽

Quark Flavour ◽

Computationally Intensive

In the Standard Model, quarks and gluons are permanently confined by the strong interaction into hadronic bound states. The values of the quark masses and the strengths of the decays of one quark flavour into another cannot be measured directly, but must be deduced from experiments on hadrons. This requires calculations of the strong-interaction effects within the bound states, which are only possible using numerical simulations of lattice QCD. These are computationally intensive and, for the past twenty years, have exploited leading-edge computing technology. In conjunction with experimental data from B Factories, over the next few years, lattice QCD may provide clues to physics beyond the Standard Model. These lectures provide a non-technical introduction to lattice QCD, some of the recent results, QCD computers, and the future prospects.

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