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Journal articles on the topic 'Massive Fundamental Scalar Particle'

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Published: 7 September 2023

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1

SIEGEMUND-BROKA, STEPHAN. "THE EFFECTIVE ACTION FOR COMPOSITE HIGGS PARTICLES." International Journal of Modern Physics A 07, no. 30 (December 10, 1992): 7561–78. http://dx.doi.org/10.1142/s0217751x92003422.

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There is reason to believe that massive composite (fermion-antifermion) scalar particles closely resembling the usual fundamental scalar Higgs fields exist in theories with dynamically broken gauge symmetries. This composite Higgs couples directly to the fermions in proportion to their symmetry-violating self-energies. Induced couplings to the gauge bosons and self-couplings are calculated as loop effects. This involves deriving the effective action in terms of the full propagators and background fields. The couplings between the composite Higgs and the gauge bosons are the same as those in models with fundamental scalars. The self-couplings are determined and fix all parameters associated with the composite scalars. Comments regarding extending this work to higher orders and concerning the symmetry-violating solutions to the fermion Schwinger-Dyson equation are given.
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2

KOK, PIETER, and SAMUEL L. BRAUNSTEIN. "RELATIVISTIC QUANTUM INFORMATION PROCESSING WITH BOSONIC AND FERMIONIC INTERFEROMETERS." International Journal of Quantum Information 04, no. 01 (February 2006): 119–30. http://dx.doi.org/10.1142/s0219749906001736.

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We derive the relativistic transformation laws for the annihilation operators of the scalar field, the massive spin-1 vector field, the electromagnetic field and the spinor field. The technique developed here involves straightforward mathematical techniques based on fundamental quantum field theory, and is applicable to the study of entanglement in arbitrary coordinate transformations. In particular, it predicts particle creation for non-inertial motion. Furthermore, we present a unified description of relativistic transformations and multi-particle interferometry with bosons and fermions, which encompasses linear optical quantum computing.
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3

Arminjon, Mayeul, and Rainer Wolfgang Winkler. "Motion of a Test Particle According to the Scalar Ether Theory of Gravitation and Application to its Celestial Mechanics." Zeitschrift für Naturforschung A 74, no. 4 (April 24, 2019): 305–16. http://dx.doi.org/10.1515/zna-2018-0470.

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AbstractThe standard interpretations of special relativity (Einstein–Minkowski) and general relativity (GR) lead to a drastically changed notion of time: the eternalism or block universe theory. This has strong consequences for our thinking about time and for the development of new fundamental theories. It is therefore important to check this thoroughly. The Lorentz–Poincaré interpretation, which sees the relativistic effects as following from a “true” Lorentz contraction of all objects in their motion through the ether, uses a conservative concept of time and is in the absence of gravitation indistinguishable from the standard interpretation; but there exists currently no accepted gravitation theory for it. The scalar ether theory of gravitation is a candidate for such a theory; it is presented and discussed. The equations of motion for a test particle are derived; the case of a uniformly moving massive body is discussed and then specialized to the case of spherical symmetry. Formulas for the acceleration of test particles are given in the preferred frame of the ether and in the rest frame of the massive body that moves with velocityVwith respect to the ether. When the body rests in the ether (V=0), the acceleration is up to orderc−2identical to GR. The acceleration of a test particle forV≠0is given; this makes it possible to fit observations in celestial mechanics to ephemerides withVas a free parameter. The current status of such fits (although to ephemerides and not to observations) is presented and discussed.
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Mikki, Said. "Fundamental Spacetime Representations of Quantum Antenna Systems." Foundations 2, no. 1 (March 2, 2022): 251–89. http://dx.doi.org/10.3390/foundations2010019.

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We utilize relativistic quantum mechanics to develop general quantum field-theoretic foundations suitable for understanding, analyzing, and designing generic quantum antennas for potential use in secure quantum communication systems and other applications. Quantum antennas are approached here as abstract source systems capable of producing what we dub “quantum radiation.” We work from within a generic relativistic framework, whereby the quantum antenna system is modeled in terms of a fundamental quantum spacetime field. After developing a framework explaining how quantum radiation can be understood using the methods of perturbative relativistic quantum field theory (QFT), we investigate in depth the problem of quantum radiation by a controlled abstract source functions. We illustrate the theory in the case of the neutral Klein-Gordon linear quantum antenna, outlining general methods for the construction of the Green’s function of a source—receiver quantum antenna system, the latter being useful for the computation of various candidate angular quantum radiation directivity and gain patterns analogous to the corresponding concepts in classical antenna theory. We anticipate that the proposed formalism may be extended to deal with a large spectrum of other possible controlled emission types for quantum communications applications, including, for example, the production of scalar, fermionic, and bosonic particles, where each could be massless or massive. Therefore, our goal is to extend the idea of antenna beyond electromagnetic waves, where now our proposed QFT-based concept of a quantum antenna system could be used to explore scenarios of controlled radiation of any type of relativistic particles, i.e., effectively transcending the well-known case of photonic systems through the deployment of novel non-standard quantum information transmission carriers such as massive photons, spin-1/2 particles, gravitons, antiparticles, higher spin particles, and so on.
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Jordan, Stephen P., Keith S. M. Lee, and John Preskill. "Quantum computation of scattering in scalar quantum field theories." Quantum Information and Computation 14, no. 11&12 (September 2014): 1014–80. http://dx.doi.org/10.26421/qic14.11-12-8.

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Quantum field theory provides the framework for the most fundamental physical theories to be confirmed experimentally and has enabled predictions of unprecedented precision. However, calculations of physical observables often require great computational complexity and can generally be performed only when the interaction strength is weak. A full understanding of the foundations and rich consequences of quantum field theory remains an outstanding challenge. We develop a quantum algorithm to compute relativistic scattering amplitudes in massive $\phi^4$ theory in spacetime of four and fewer dimensions. The algorithm runs in a time that is polynomial in the number of particles, their energy, and the desired precision, and applies at both weak and strong coupling. Thus, it offers exponential speedup over existing classical methods at high precision or strong coupling.
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6

Armand, C., and B. Herrmann. "Dark matter indirect detection limits from complete annihilation patterns." Journal of Cosmology and Astroparticle Physics 2022, no. 11 (November 1, 2022): 055. http://dx.doi.org/10.1088/1475-7516/2022/11/055.

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Abstract While cosmological and astrophysical probes suggest that dark matter would make up for 85% of the total matter content of the Universe, the determination of its nature remains one of the greatest challenges of fundamental physics. Assuming the ΛCDM cosmological model, Weakly Interacting Massive Particles would annihilate into Standard Model particles, yielding γ-rays, which could be detected by ground-based telescopes. Dwarf spheroidal galaxies represent promising targets for such indirect searches as they are assumed to be highly dark matter dominated with the absence of astrophysical sources nearby. Previous studies have led to upper limits on the annihilation cross-section assuming single exclusive annihilation channels. In this work, we consider a more realistic situation and take into account the complete annihilation pattern within a given particle physics model. This allows us to study the impact on the derived upper limits on the dark matter annihilation cross-section from a full annihilation pattern compared to the case of a single annihilation channel. We use mock data for the Cherenkov Telescope Array simulating the observations of the promising dwarf spheroidal galaxy Sculptor. We show the impact of considering the full annihilation pattern within a simple framework where the Standard Model of particle physics is extended by a singlet scalar. Such a model shows new features in the shape of the predicted upper limit which reaches a value of 〈σv〉 = 3.8 × 10-24 cm-3s-1 for a dark matter mass of 1 TeV at 95% confidence level. We suggest considering the complete particle physics information in order to derive more realistic limits.
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FLAMBAUM, V. V. "VARIATION OF THE FUNDAMENTAL CONSTANTS: THEORY AND OBSERVATIONS." International Journal of Modern Physics A 22, no. 27 (October 30, 2007): 4937–50. http://dx.doi.org/10.1142/s0217751x07038293.

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Review of recent works devoted to the variation of the fine structure constant α, strong interaction and fundamental masses (Higgs vacuum) is presented. The results from Big Bang nucleosynthesis, quasar absorption spectra, and Oklo natural nuclear reactor data give us the space-time variation on the Universe lifetime scale. Comparison of different atomic clocks gives us the present time variation. Assuming linear variation with time we can compare different results. The best limit on the variation of the electron-to-proton mass ratio μ = me/Mp and Xe = me/ΛQCD follows from the quasar absorption spectra:1[Formula: see text]. A combination of this result and the atomic clock results2,3 gives the best limt on variation of [Formula: see text]. The Oklo natural reactor gives the best limit on the variation of Xs = ms/ΛQCD where ms is the strange quark mass:4,5[Formula: see text]. Note that the Oklo data can not give us any limit on the variation of α since the effect of α there is much smaller than the effect of Xs and should be neglected. Huge enhancement of the relative variation effects happens in transitions between close atomic, molecular and nuclear energy levels. We suggest several new cases where the levels are very narrow. Large enhancement of the variation effects is also possible in cold atomic and molecular collisions near Feshbach resonance. How changing physical constants and violation of local position invariance may occur? Light scalar fields very naturally appear in modern cosmological models, affecting parameters of the Standard Model (e.g. α). Cosmological variations of these scalar fields should occur because of drastic changes of matter composition in Universe: the latest such event is rather recent (about 5 billion years ago), from matter to dark energy domination. Massive bodies (stars or galaxies) can also affect physical constants. They have large scalar charge S proportional to number of particles which produces a Coulomb-like scalar field U = S/r. This leads to a variation of the fundamental constants proportional to the gravitational potential, e.g. δα/α = kαδ(GM/rc2). We compare different manifestations of this effect. The strongest limits6kα + 0.17ke = (-3.5 ±6) × 10-7 and kα + 0.13kq = (-1 ± 17) × 10-7 are obtained from the measurements of dependence of atomic frequencies on the distance from Sun2,7 (the distance varies due to the ellipticity of the Earth's orbit).
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8

Duff, M. J., and K. S. Stelle. "Sir Thomas Walter Bannerman Kibble. 23 December 1932—2 June 2016." Biographical Memoirs of Fellows of the Royal Society 70 (March 24, 2021): 225–44. http://dx.doi.org/10.1098/rsbm.2020.0040.

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Professor Tom Kibble was an internationally-renowned theoretical physicist whose contributions to theoretical physics range from the theory of elementary particles to modern early-Universe cosmology. The unifying theme behind all his work is the theory of non-abelian gauge theories, the Yang–Mills extension of electromagnetism. One of Kibble's most important pieces of work in this area was his study of the symmetry-breaking mechanism whereby the force-carrying vector particles in the theory can acquire a mass accompanied by the appearance of a massive scalar boson. This idea, put forward independently by Brout and Englert, by Higgs, and by Guralnik, Hagen and Kibble in 1964, and generalized by Kibble in 1967, lies at the heart of the Standard Model and all modern unified theories of fundamental particles. It was vindicated in 2012 by the discovery of the Higgs boson at CERN. According to Nobel Laureate Steven Weinberg: ‘Tom Kibble showed us why light is massless’; this is the fundamental basis of electromagnetism.
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9

Cremaschini, Claudio, and Massimo Tessarotto. "Hamilton–Jacobi Wave Theory in Manifestly-Covariant Classical and Quantum Gravity." Symmetry 11, no. 4 (April 24, 2019): 592. http://dx.doi.org/10.3390/sym11040592.

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The axiomatic geometric structure which lays at the basis of Covariant Classical and Quantum Gravity Theory is investigated. This refers specifically to fundamental aspects of the manifestly-covariant Hamiltonian representation of General Relativity which has recently been developed in the framework of a synchronous deDonder–Weyl variational formulation (2015–2019). In such a setting, the canonical variables defining the canonical state acquire different tensorial orders, with the momentum conjugate to the field variable g μ ν being realized by the third-order 4-tensor Π μ ν α . It is shown that this generates a corresponding Hamilton–Jacobi theory in which the Hamilton principal function is a 4-tensor S α . However, in order to express the Hamilton equations as evolution equations and apply standard quantization methods, the canonical variables must have the same tensorial dimension. This can be achieved by projection of the canonical momentum field along prescribed tensorial directions associated with geodesic trajectories defined with respect to the background space-time for either classical test particles or raylights. It is proved that this permits to recover a Hamilton principal function in the appropriate form of 4-scalar type. The corresponding Hamilton–Jacobi wave theory is studied and implications for the manifestly-covariant quantum gravity theory are discussed. This concerns in particular the possibility of achieving at quantum level physical solutions describing massive or massless quanta of the gravitational field.
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10

KHUSNUTDINOV, NAIL. "SELF-INTERACTION FOR PARTICLES IN THE WORMHOLE SPACE-TIMES." International Journal of Modern Physics A 26, no. 22 (September 10, 2011): 3868–77. http://dx.doi.org/10.1142/s0217751x11054322.

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The self-energy and self-force for particles with electric and scalar charges at rest in the space-time of massless and massive wormholes are considered. The particle with electric charge is always attracted to wormhole throat for arbitrary profile of the throat. The self-force for scalar particle shows different behavior depending on the non-minimal coupling. The self-force for massive scalar field is localized close to the throat of the wormhole.
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KHUSNUTDINOV, NAIL. "SELF-INTERACTION FOR PARTICLES IN THE WORMHOLE SPACE-TIMES." International Journal of Modern Physics: Conference Series 03 (January 2011): 354–63. http://dx.doi.org/10.1142/s2010194511001450.

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The self-energy and self-force for particles with electric and scalar charges at rest in the space-time of massless and massive wormholes are considered. The particle with electric charge is always attracted to wormhole throat for arbitrary profile of the throat. The self-force for scalar particle shows different behavior depending on the non-minimal coupling. The self-force for massive scalar field is localized close to the throat of the wormhole.
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12

KOWALSKI-GLIKMAN, J., and J. LUKIERSKI. "MASSIVE SPINNING SUPERPARTICLE." Modern Physics Letters A 04, no. 25 (November 30, 1989): 2437–45. http://dx.doi.org/10.1142/s0217732389002720.

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We consider new supersymmetric particle model, describing the massive extension of D=4 spinning superparticle model, derived in Ref. 1. It is shown that our model can be described by the D=5 massless spinning superparticle model after dimensional reduction D=5→D=4 and putting the fifth momentum P5=m. The known massive superparticle and massive spinning particle models can be obtained as special cases. The first quantization of the massive spinning superparticle model gives a N=2 massive vector multiplet (one complex scalar, two Dirac spinors, one massive complex vector field).
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13

DAREWYCH, JURIJ W., MARKO HORBATSCH, and ROMAN KONIUK. "RELATIVISTIC CHARGED PARTICLE SCATTERING WITH SPIN SPIN INTERACTIONS." International Journal of Modern Physics E 01, no. 01 (March 1992): 147–67. http://dx.doi.org/10.1142/s0218301392000072.

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We consider scattering solutions to relativistic wave equations derived within the framework of a Hamiltonian variational method for Quantum Electrodynamics. The wave equations contain the spin-dependent Breit interaction terms as the Fock-space Ansatz samples the transverse photon degrees of freedom. For the case of uncharged scalar particles exchanging massive bosons (scalar Yukawa model) reasonable agreement with a solution of the Bethe–Salpeter equation in ladder approximation is obtained. For the case of the pseudoscalar and scalar channels in QED, we determine the phase shifts as a function of energy.
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14

RAYCHAUDHURI, B., F. RAHAMAN, M. KALAM, and A. GHOSH. "MOTION OF MASSIVE AND MASSLESS TEST PARTICLES IN DYADOSPHERE GEOMETRY." Modern Physics Letters A 24, no. 16 (May 30, 2009): 1277–87. http://dx.doi.org/10.1142/s0217732309029971.

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Motion of massive and massless test particle in equilibrium and nonequilibrium case is discussed in a dyadosphere geometry through Hamilton–Jacobi method. Scalar wave equation for massless particle is analyzed to show the absence of superradiance in the case of dyadosphere geometry.
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15

Darewych, J. W., and P. Biswas. "Single quantum pair annihilation of a bound particle–particle–antiparticle system." Canadian Journal of Physics 76, no. 4 (April 1, 1998): 283–93. http://dx.doi.org/10.1139/p98-009.

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A relativistic coupled channel formalism is presented for the description of a quasi-bound three-body state.The annihilation of a particle–particle–antiparticle system into a particle and a single quantum is studied in the scalar Yukawa model, in which scalar "nucleons" (ϕ) and "antinucleons" ([Formula: see text]) interact via scalar "meson" χ exchange. A three-Fock-state trial state is used to derive variational equations that describe the quasi-bound [Formula: see text] system as a resonance in the χ ϕ collision channel. These equations are solved approximately to yield the [Formula: see text] decay width. This width is found to be negligible compared with the two-quantum pair annihilation width if the coupling is weak (α << 1), but is found to be of comparable magnitude for strong coupling (α [Formula: see text] 1). Relativistic effects on the width are pronounced and cannot be neglected at strong coupling. Order of magnitude comparison is made with the Ps¯ system for the massless-χ case, and to nuclear [Formula: see text] systems for the massive-χcase. PACS Nos. 11.10Qr and 11.10st
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KIM, SUNG KU, KWANG-SUP SOH, JAE HYUNG YEE, DAE SUNG HWANG, and WUK NAMGUNG. "SYMPLECTIC STRUCTURE OF LINEAR GRAVITY COUPLED TO A MASSIVE PARTICLE." Modern Physics Letters A 10, no. 39 (December 21, 1995): 3009–19. http://dx.doi.org/10.1142/s0217732395003148.

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Jackiw-Teitelboim model of linear gravity coupled to a point particle is studied in a curved cylindrical spacetime. The classical solutions for the metric, the particle trajectory, and the scalar field are explicitly given. We studied the symplectic structure on the phase space of the classical solutions.
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Leo, Leo Di, and Jurij W. Darewych. "Bound and resonant relativistic two-particle states in scalar quantum field theory." Canadian Journal of Physics 70, no. 6 (June 1, 1992): 412–26. http://dx.doi.org/10.1139/p92-071.

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We derive relativistic particle–antiparticle wave equations for scalar particles, [Formula: see text] and [Formula: see text], interacting via a massive or massless scalar field, χ (the Wick–Cutkosky model). The variational method, within the Hamiltonian formalism of quantum field theory is used to derive equations with and without coupling of this quasi-bound [Formula: see text] system to the χχ decay channel. Bound-state energies in the massless case are compared with the ladder Bethe–Salpeter and light-cone results. In the case of coupling to the decay channel, the quasi-bound [Formula: see text] states are seen to arise as resonances in the χχ scattering cross section. Numerical results are presented for the massive and massless χ case.
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18

Ishida, K., C. B. Kim, and K. Yoshida. "Massive Charged Scalar Particle in the Three-Dimensional Einstein-Maxwell Theory." Progress of Theoretical Physics 84, no. 1 (July 1, 1990): 172–78. http://dx.doi.org/10.1143/ptp/84.1.172.

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19

Dorn, Harald, and George Jorjadze. "Oscillator quantization of the massive scalar particle dynamics on AdS spacetime." Physics Letters B 625, no. 1-2 (October 2005): 117–26. http://dx.doi.org/10.1016/j.physletb.2005.08.059.

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20

Leo, Leo Di, and Jurij W. Darewych. "Relativistic three-particle bound states in scalar quantum field theory." Canadian Journal of Physics 71, no. 7-8 (July 1, 1993): 365–79. http://dx.doi.org/10.1139/p93-058.

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We derive relativistic three-particle wave equations for scalar particles [Formula: see text], [Formula: see text], and [Formula: see text], interacting via a massive or massless scalar field, χ. The variational method, within the Hamiltonian formalism of quantum field theory, is used to obtain the equations using a simple [Formula: see text] Ansatz. Approximate solutions of these equations are presented for various strengths of the coupling. The magnitude of the relativistic effects in the three-particle energies and wave functions is illustrated by comparison with nonrelativistic results.
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21

KIM, SANG PYO. "PROBING THE VACUUM STRUCTURE OF SPACETIME." International Journal of Modern Physics: Conference Series 12 (January 2012): 310–19. http://dx.doi.org/10.1142/s2010194512006514.

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We explore the question of how to probe the vacuum structure of space time by a massive scalar field through interaction with background gravitons. Using the Γ-regularization for the in-/out-state formalism, we find the effective action of a scalar field in a conformally, asymptotically flat spacetime and a four-dimensional de Sitter space, which is a gravitational analog of the Heisenberg-Euler and Schwinger effective action for a charged scalar in a constant electric field. The effective action is nonperturbative in that it sums all one-loop diagrams with arbitrary number of external lines of gravitons. The massive scalar field becomes unstable due to particle production, the effective action has an imaginary part that determines the decay rate of the vacuum, and the out-vacuum is unitarily inequivalent to the in-vacuum.
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Darewych, J. W. "Some exact solutions of reduced scalar Yukawa theory." Canadian Journal of Physics 76, no. 7 (June 3, 1998): 523–37. http://dx.doi.org/10.1139/p98-036.

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The scalar Yukawa model, in which a complex scalar field, ϕ, interacts via a real scalar field, χ, is reduced by using covariant Green functions. It is shown that exact few-particle eigenstates of the truncated QFT Hamiltonian can be obtained in the Feshbach–Villars formulation if an unorthodox "empty" vacuum state is used. Analytic solutions for the two-body case are obtained for massless chion exchange in 3+1 dimensions and for massive chion exchange in 1+1 dimensions. Comparison is made to ladder Bethe–Salpeter, Feynman–Schwinger, and quasipotential results for massive chion exchange in 3+1. Equations for the three-body case are also obtained. PACS Nos.: 11.10.Ef, 11.10.Qr, and 03.70.+k
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Joshi, M. P., and G. S. Khadekar. "Higher Dimensional Exact Solutions of Einstein’s Field Equations for a Massive Point Particle with Scalar Point Charge." Australian Journal of Physics 51, no. 3 (1998): 577. http://dx.doi.org/10.1071/p97042.

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The exact spherically symmetric static solution of Einstein’s field equations in higher dimensions for a massive point particle with a scalar point charge as the source of a massless scalar field is derived in Schwarzschild coordinates. There exists no Schwarzschild horizon. This result is an extension in higher dimensions of a similar one obtained by Hardell and Dehnen (1993) earlier for 4D space-time.
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Yong-jiu, Wang, and Tang Zhi-ming. "Massive scalar particle in the gravitational field of a microcosmic black hole." Chinese Physics 10, no. 8 (July 16, 2001): 679–82. http://dx.doi.org/10.1088/1009-1963/10/8/301.

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Struckmeier, J., J. Muench, P. Liebrich, M. Hanauske, J. Kirsch, D. Vasak, L. Satarov, and H. Stoecker. "Canonical transformation path to gauge theories of gravity-II: Space-time coupling of spin-0 and spin-1 particle fields." International Journal of Modern Physics E 28, no. 01n02 (February 2019): 1950007. http://dx.doi.org/10.1142/s0218301319500071.

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The generic form of space-time dynamics as a classical gauge field theory has recently been derived, based on only the action principle and on the principle of general relativity. It was thus shown that Einstein’s general relativity is the special case where (i) the Hilbert Lagrangian (essentially the Ricci scalar) is supposed to describe the dynamics of the “free” (uncoupled) gravitational field, and (ii) the energy–momentum tensor is that of scalar fields representing real or complex structureless (spin-[Formula: see text]) particles. It followed that all other source fields — such as vector fields representing massive and nonmassive spin-[Formula: see text] particles — need careful scrutiny of the appropriate source tensor. This is the subject of our actual paper: we discuss in detail the coupling of the gravitational field with (i) a massive complex scalar field, (ii) a massive real vector field, and (iii) a massless vector field. We show that different couplings emerge for massive and nonmassive vector fields. The massive vector field has the canonical energy–momentum tensor as the appropriate source term — which embraces also the energy density furnished by the internal spin. In this case, the vector fields are shown to generate a torsion of space-time. In contrast, the system of a massless and charged vector field is associated with the metric (Hilbert) energy–momentum tensor due to its additional [Formula: see text] symmetry. Moreover, such vector fields do not generate a torsion of space-time. The respective sources of gravitation apply for all models of the dynamics of the “free” (uncoupled) gravitational field — which do not follow from the gauge formalism but must be specified based on separate physical reasoning.
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Fazio, A. R., and E. A. Reyes R. "A functional approach to the next-to-eikonal approximation of high energy gravitational scattering." Modern Physics Letters A 36, no. 20 (June 24, 2021): 2150138. http://dx.doi.org/10.1142/s0217732321501388.

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The Fradkin–Schwinger functional methods to represent a Green function in an external gravitational field are used to study the eikonal and the next-to-eikonal limit, including the nonlinear gravitational interactions, of the scattering amplitudes of an ultra-relativistic scalar particle on a static super-massive scalar target in the nearly forward limit. The functional approach confirms the exponentiation of the leading eikonal which also applies to the first non-leading power in the energy of the light particle, moreover includes the interaction at impact parameter much larger than the Schwarzschild radius associated with the center of mass energy in the ultra-relativistic limit.
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RAJPOOT, SUBHASH. "MASSIVE DIRAC NEUTRINOS AND SN1987A." Modern Physics Letters A 08, no. 13 (April 30, 1993): 1179–84. http://dx.doi.org/10.1142/s021773239300266x.

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If neutrinos are massive Dirac particles, their right-handed components are inert to interactions with matter. However, the helicity flip mechanism due to the mass term can participate in the cooling of a new born star. The observed neutrino bursts from SN1987A constrained Dirac neutrino masses to lie between 1 keV and 10 keV so as to avoid rapid cooling due to the mass induced helicity flip mechanism. We suggest scalar particle mediated new interactions between the right-handed neutrinos and nuclear matter that trap the right-handed neutrinos long enough so that the total energy of the exploding star is carried away predominantly by left-handed neutrinos. The bounds from cosmology are also shown to be satisfied.
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Creminelli, Paolo, Soubhik Kumar, Borna Salehian, and Luca Santoni. "Dissipative inflation via scalar production." Journal of Cosmology and Astroparticle Physics 2023, no. 08 (August 1, 2023): 076. http://dx.doi.org/10.1088/1475-7516/2023/08/076.

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Abstract We describe a new mechanism that gives rise to dissipation during cosmic inflation. In the simplest implementation, the mechanism requires the presence of a massive scalar field with a softly-broken global U(1) symmetry, along with the inflaton field. Particle production in this scenario takes place on parametrically sub-horizon scales, at variance with the case of dissipation into gauge fields. Consequently, the backreaction of the produced particles on the inflationary dynamics can be treated in a local manner, allowing us to compute their effects analytically. We determine the parametric dependence of the power spectrum which deviates from the usual slow-roll expression. Non-Gaussianities are always sizeable whenever perturbations are generated by the noise induced by dissipation: f NL eq ≳ O(10).
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Keller, O. "Photon wave mechanics in the eikonal limit: Diamagnetic field-plasma interaction." Laser and Particle Beams 26, no. 2 (June 2008): 287–94. http://dx.doi.org/10.1017/s0263034608000359.

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AbstractA microscopic eikonal theory based on photon wave mechanics is established. The diamagnetic (solid state) field-plasma interaction is shown to play a central role in the theory, and this interaction enables one to introduce a massive transverse photon concept. This quasi-particle enters the eikonal theory in manner similar to the one in which the classical point particle enters Newtonian Mechanics in the Hamilton-Jacobi formulation. When the spatial fluctuations in the stationary-state plasma density are of importance the microscopic eikonal theory becomes a spatially nonlocal theory, and the nonlocality, originating in the coupling of longitudinal and scalar photons to the massive transverse photon, extends over near-field distances.
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MORADI, SHAHPOOR. "PARTICLE CREATION AND UIRs OF DE SITTER GROUP." Modern Physics Letters A 23, no. 21 (July 10, 2008): 1793–800. http://dx.doi.org/10.1142/s0217732308025851.

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In this paper using the first Casimir operator of de Sitter group we obtain the field equations for spin-0 and spin-1/2 fields. After finding the exact solutions, we calculate the Bogoliubov coefficients and the particle creation rate for scalar and Dirac particles. Three series of inequivalent representations are distinguished for de Sitter group: the principal, complementary and discrete series. It is shown that only for principal series massive particles are produced. The thermal particle creation rate is compared with the previous results and it is shown that the results are the same.
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31

Paraskevopoulos, Christos. "Measurement of the Higgs quartic coupling c 2 v from di-Higgs Vector Boson Fusion in the bb¯τ+τ− channel." Journal of Physics: Conference Series 2375, no. 1 (November 1, 2022): 012009. http://dx.doi.org/10.1088/1742-6596/2375/1/012009.

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Abstract The Brout Englert Higgs (BEH) mechanism of electroweak symmetry breaking and mass generation was experimentally confirmed after the discovery of the Higgs boson at the Large Hadron Collider in 2012. The BEH mechanism not only predicts the existence of a massive scalar particle, but also requires this scalar particle to couple to itself. Double Higgs production provides a unique handle, since it allows the extraction of the trilinear Higgs self-coupling. VBF di-Higgs production also probes the quartic Higgs bosons to vector bosons coupling (c 2 v). In this topic the effort on setting constraints on c 2 v will be discussed. Event selection and reconstruction will be illustrated as well as a Neural Network designed to identify VBF events.
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32

Chigodaev, Alexander, and Jurij W. Darewych. "Interparticle potentials in a scalar quantum field theory with a Higgs-like mediating field." Canadian Journal of Physics 91, no. 4 (April 2013): 279–92. http://dx.doi.org/10.1139/cjp-2012-0251.

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We study the interparticle potentials for few-particle systems in a scalar theory with a nonlinear mediating field of the Higgs type. We use the variational method, in a reformulated Hamiltonian formalism of quantum field theory, to derive relativistic three- and four-particle wave equations for stationary states of these systems. We show that the cubic and quartic nonlinear terms modify the attractive Yukawa potentials but do not change the attractive nature of the interaction if the mediating fields are massive.
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33

Gecim, Ganim, and Yusuf Sucu. "The GUP Effect on Tunneling of Massive Vector Bosons from The 2+1 Dimensional Black Hole." Advances in High Energy Physics 2018 (June 25, 2018): 1–8. http://dx.doi.org/10.1155/2018/7031767.

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In this study, the Generalized Uncertainty Principle (GUP) effect on the Hawking radiation formed by tunneling of a massive vector boson particle from the 2+1 dimensional new-type black hole was investigated. We used modified massive vector boson equation based on the GUP. Then, the Hamilton-Jacobi quantum tunneling approach was used to work out the tunneling probability of the massive vector boson particle and Hawking temperature of the black hole. Due to the GUP effect, the modified Hawking temperature was found to depend on the black hole properties, on the AdS3 radius, and on the energy, mass, and total angular momentum of the tunneling massive vector boson. In the light of these results, we also observed that modified Hawking temperature increases by the total angular momentum of the particle while it decreases by the energy and mass of the particle and the graviton mass. Also, in the context of the GUP, we see that the Hawking temperature due to the tunneling massive vector boson is completely different from both that of the spin-0 scalar and that of the spin-1/2 Dirac particles obtained in the previous study. We also calculate the heat capacity of the black hole using the modified Hawking temperature and then discuss influence of the GUP on the stability of the black hole.
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34

Nesbet, Robert K. "Conformal Higgs model: Gauge fields can produce a 125 GeV resonance." Modern Physics Letters A 36, no. 22 (July 20, 2021): 2150161. http://dx.doi.org/10.1142/s0217732321501613.

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Recent cosmological observations and compatible theory offer an understanding of long-mysterious dark matter and dark energy. The postulate of universal conformal local Weyl scaling symmetry, without dark matter, modifies action integrals for both Einstein–Hilbert gravitation and the Higgs scalar field by gravitational terms. Conformal theory accounts for both observed excessive external galactic orbital velocities and for accelerating cosmic expansion. SU(2) symmetry-breaking is retained by the conformal scalar field, which does not produce a massive Higgs boson, requiring an alternative explanation of the observed LHC 125 GeV resonance. Conformal theory is shown here to be compatible with a massive neutral particle or resonance [Formula: see text] at 125 GeV, described as binary scalars [Formula: see text] and [Formula: see text] interacting strongly via quark exchange. Decay modes would be consistent with those observed at LHC. Massless scalar field [Formula: see text] is dressed by the [Formula: see text] field to produce Higgs Lagrangian term [Formula: see text] with the empirical value of [Formula: see text] known from astrophysics.
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35

Radu, D., and D. Tatomir. "Gravitational scattering of massive particles on a background with axial symmetry." Canadian Journal of Physics 76, no. 1 (January 1, 1998): 1–22. http://dx.doi.org/10.1139/p97-026.

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Using the S-matrix formalism and the Feynman diagram technique, the gravitational scattering of the minimally and non-minimally coupled scalar, spinor, vector, spin-vector, and spin-2 massive particles, in a background described by Kerr–Newman geometry is studied for any value of the scattering angle. We find that the differential cross sections of the scalar, spinor, and vector particles in the backward direction and ultrarelativistic case are finite and consequently the backscattered particles must have the opposite helicity, whereas for the spin-vector and spin-2 particles in the same case, the differential cross sections are clearly infinite. It has been shown, for the particular case when the angular momentum of the scatterer vanishes (i.e., for the Schwarzschild geometry) and in the small-angle approximation and ultrarelativistic limit as well, the differential cross sections are all of the same type, i.e., in this special limit case the gravitational particle scattering is spin independent. PACS Nos. 03.80+r, 11.80-m, 03.70+k
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36

Jamet, P., and A. Drezet. "A classical analog of the quantum Zeeman effect." Chaos: An Interdisciplinary Journal of Nonlinear Science 32, no. 3 (March 2022): 033101. http://dx.doi.org/10.1063/5.0081254.

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We extend a recent classical mechanical analog of Bohr’s atom consisting of a scalar field coupled to a massive point-like particle [P. Jamet and A. Drezet, “A mechanical analog of Bohr’s atom based on de Broglie’s double-solution approach,” Chaos 31, 103120 (2021)] by adding and studying the contribution of a uniform weak magnetic field on their dynamics. In doing so, we are able to recover the splitting of the energy levels of the atom called Zeeman’s effect within the constraints of our model and in agreement with the semiclassical theory of Sommerfeld. This result is obtained using Larmor’s theorem for both the field and the particle, associating magnetic effects with inertial Coriolis forces in a rotating frame of reference. Our work, based on the old “double solution” theory of de Broglie, shows that a dualistic model involving a particle guided by a scalar field can reproduce the normal Zeeman effect.
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37

BARSHAY, SAUL, and GEORG KREYERHOFF. "LONG-RANGE INTERACTIONS BETWEEN DARK-MATTER PARTICLES IN A MODEL WITH A COSMOLOGICAL, SPONTANEOUSLY-BROKEN CHIRAL SYMMETRY." Modern Physics Letters A 20, no. 15 (May 20, 2005): 1155–60. http://dx.doi.org/10.1142/s0217732305017329.

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In a cosmological model with a chiral symmetry, there are two, dynamically-related spin-zero fields, a scalar ϕ and a pseudoscalar b. These fields have self-interactions. Spontaneous symmetry breaking results in a very massive scalar particle with mϕ≅5×1011 GeV , and a nearly massless, (Goldstone-like) pseudoscalar particle with 0<mb≲2.7×10-6 eV . One or both particles can be part of dark matter. There are coherent long-range interactions (at range ~ 1/mb≳10 cm ), from exchange of a b particle between a pair of b particles, a pair of ϕ particles, and between a ϕ and a b. We compare the strength of potentials for the different pairs to the corresponding gravitational potentials (within the same range ~ 1/mb), and show that the new force dominates between a b pair, that gravitation dominates between a ϕ pair, and that the potentials are comparable for a ϕ-b pair. The new interaction strength between a b pair is comparable to the gravitational interaction between a ϕ pair; its possibly greater coherent effect originates in the possibility that the number density of a very light b can be greater than that of a massive ϕ. We consider these results in the context of recent speculations concerning possible effects of special forces between dark-matter particles on certain galactic, and inter-galactic, properties.
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38

Nieto, Carlos M., and Yeinzon Rodríguez. "Massive gauge-flation." Modern Physics Letters A 31, no. 21 (July 10, 2016): 1640005. http://dx.doi.org/10.1142/s0217732316400058.

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Gauge-flation model at zeroth-order in cosmological perturbation theory offers an interesting scenario for realizing inflation within a particle physics context, allowing us to investigate interesting possible connections between inflation and the subsequent evolution of the Universe. Difficulties, however, arise at the perturbative level, thus motivating a modification of the original model. In order to agree with the latest Planck observations, we modify the model such that the new dynamics can produce a relation between the spectral index n[Formula: see text] and the tensor-to-scalar ratio r allowed by the data. By including an identical mass term for each of the fields of the system, we find interesting dynamics leading to slow-roll inflation of the right length. The presence of the mass term has the potential to modify the n[Formula: see text] versus r relation so as to agree with the data. As a first step, we study the model at zeroth-order in cosmological perturbation theory, finding the conditions required for slow-roll inflation and the number of e-foldings of inflation. Numerical solutions are used to explore the impact of the mass term. We conclude that the massive version of gauge-flation offers a viable inflationary model.
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39

Li, Weijun, Bo Yang, Cunliang Ma, Xia Zhou, Zhongwen Feng, and Guansheng He. "Periastron precession due to a Janis–Newman–Winicour wormhole in the weak field limit." Modern Physics Letters A 36, no. 22 (July 20, 2021): 2150164. http://dx.doi.org/10.1142/s0217732321501649.

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The precession effect of periastron for a massive test particle in the spacetime of a Janis–Newman–Winicour wormhole is studied in the weak field limit. Based on the metric of this static and spherically symmetric wormhole in harmonic coordinates, we derive the second post-Newtonian dynamics of the particle. The second-order orbital precession of periastron is then obtained via a post-Newtonian iterative technique under the Wagoner–Will–Epstein–Haugan representation. Our result is found to be consistent with the classical precession effect when the asymptotic scalar charge is dropped.
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40

Gossel, G. H., V. V. Flambaum, and J. C. Berengut. "Resonance scattering and the passage to bound states in the field of near-black-hole objects." International Journal of Modern Physics D 23, no. 11 (October 2014): 1450089. http://dx.doi.org/10.1142/s0218271814500898.

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In this paper, we examine the spectrum of a massive scalar particle interacting with the strong gravitational field of a static, spherically symmetric object which is not quite massive enough to be a black hole. As was found in the case of massless particles, there exists a dense spectrum of long lived resonances (meta-stable states), which leads to an energy-averaged cross-section for particle capture which approaches the absorption cross-section for a Schwarzschild black hole. However, the generalization to nonzero mass introduces new phenomena, along with important qualitative changes to the scattering properties. In contrast to the massless case, there exists a spectrum of bound states with almost identical structure to that of the resonances, allowing for the possibility of radiative transitions and particle capture. The resonance lifetimes for elastic processes are parametrically larger than for massless particles, meaning the absorption cross-section approaches the black hole case faster than for massless scalars.
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41

MAEDA, KEI-ICHI. "ON TIME VARIATION OF FUNDAMENTAL CONSTANTS IN SUPERSTRING THEORIES." Modern Physics Letters A 03, no. 03 (February 1988): 243–49. http://dx.doi.org/10.1142/s0217732388000295.

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Assuming the action from the string theory and taking into account the dynamical freedom of a dilaton and its coupling to matter fluid, we show that fundamental ‘constants’ in string theories are independent of the ‘radius’ of the internal space. Since the scalar related to the ‘constants’ is coupled to the 4-dimensional gravity and matter fluid in the same way as in the Jordan-Brans-Dicke theory with ω=−1, it must be massive and can get a mass easily through some symmetry breaking mechanism (e.g. the SUSY breaking due to a gluino condensation). Consequently, time variation of fundamental constants is too small to be observed.
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42

DODELSON, SCOTT, and LAWRENCE M. WIDROW. "BARYOGENESIS WITHOUT BARYON NUMBER VIOLATION." Modern Physics Letters A 05, no. 21 (August 30, 1990): 1623–28. http://dx.doi.org/10.1142/s0217732390001852.

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We review a new paradigm for baryogenesis in which the fundamental Lagrangian is baryon conserving [invariant under U (1) B ]. At high temperatures, U (1)B is spontaneously broken and an excess of quarks over antiquarks of 10−10s (s≡entropy density) is produced. Today, U(1)B is restored. A fundamental consequence of our assumptions is that the baryon number of the Universe is constant. If initially zero, it will be zero today. The excess baryon number produced in the quark fields is exactly compensated by antibaryon number in a weakly interacting scalar particle. We suggest that this scalar provides the mass density necessary to close the Universe.
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43

Roos, M., S. Bowyer, M. Lampton, and J. T. Peltoniemi. "Do Massive Neutrinos Ionize Intergalactic HI?" Symposium - International Astronomical Union 168 (1996): 563–67. http://dx.doi.org/10.1017/s0074180900110708.

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The radiative decay of massive relic 30eV neutrinos could explain several observational puzzles including the missing dark matter in the universe and the anomalous degree of ionization of interstellar matter in the Galaxy. We note that various non-standard particle physics models with extended scalar sector or minimal supersymmetry have sufficient freedom to accommodate such neutrinos. We discuss observational constraints in the immediate Solar neighborhood, in nearby regions of low interstellar absorption, in the Galactic halo, in clusters of galaxies, and in extragalactic space. Although some observations have been interpreted as ruling out this picture, we note that this is true only for models in which extreme concentrations of neutrinos occur in clusters of galaxies. An instrument is under development to measure the cosmic diffuse EUV background in the local Solar neighborhood, for flight on the Spanish Minisat satellite platform. This instrument will have the capability of providing a definitive test of the radiative neutrino decay hypothesis.
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44

Drukier, A. K., K. Freese, and D. N. Spergel. "Detecting Cold Dark Matter Candidates." Symposium - International Astronomical Union 117 (1987): 490. http://dx.doi.org/10.1017/s0074180900150703.

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We consider the use of superheated superconducting colloids as detectors of weakly interacting galactic halo candidate particles (e.g. photinos, massive neutrinos, and scalar neutrinos). These low temperature detectors are sensitive to the deposition of a few hundreds of eV's. The recoil of a dark matter particle off of a superheated superconducting grain in the detector causes the grain to make a transition to the normal state. Their low energy threshold makes this class of detectors ideal for detecting massive weakly interacting halo particles.We discuss realistic models for the detector and for the galactic halo. We show that the expected count rate (≈103 count/day for scalar and massive neutrinos) exceeds the expected background by several orders of magnitude. For photinos, we expect ≈1 count/day, more than 100 times the predicted background rate. We find that if the detector temperature is maintained at 50 mK and the system noise is reduced below 5 × 10−4 flux quanta, particles with mass as low as 2 GeV can be detected. We show that the earth's motion around the Sun can produce a significant annual modulation in the signal.
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45

Hardell, A., and H. Dehnen. "Exact solutions of Einstein's field equations for a massive point-particle with scalar point-charge." General Relativity and Gravitation 25, no. 11 (November 1993): 1165–73. http://dx.doi.org/10.1007/bf00763759.

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46

BOOS, EDWARD E., YURI S. MIKHAILOV, MIKHAIL N. SMOLYAKOV, and IGOR P. VOLOBUEV. "PHYSICAL DEGREES OF FREEDOM IN STABILIZED BRANE WORLD MODELS." Modern Physics Letters A 21, no. 18 (June 14, 2006): 1431–49. http://dx.doi.org/10.1142/s0217732306020792.

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We consider brane world models with interbrane separation stabilized by the Goldberger–Wise scalar field. For arbitrary background, or vacuum configurations of the gravitational and scalar fields in such models, we construct the second variation Lagrangian, study its gauge invariance, find the corresponding equations of motion and decouple them in a suitable gauge. We also derive an effective four-dimensional Lagrangian for such models, which describes the massless graviton, a tower of massive gravitons and a tower of massive scalars. It is shown that for a special choice of the background solution the masses of the graviton excitations may be of the order of 1 TeV, the radion mass of the order of 100 GeV, the inverse size of the extra dimension being 1 TeV. In this case the coupling of the radion to matter on the negative tension brane is approximately ten times weaker than in the unstabilized model with the same values of the fundamental five-dimensional energy scale and the interbrane distance.
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47

Ahmed, Faizuddin. "Investigation of a Spin-0 Massive Charged Particle Subject to a Homogeneous Magnetic Field with Potentials in a Topologically Trivial Flat Class of Gödel-Type Space-Time." Advances in High Energy Physics 2020 (June 10, 2020): 1–10. http://dx.doi.org/10.1155/2020/7943436.

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In this paper, we investigate the relativistic quantum dynamics of spin-0 massive charged particle subject to a homogeneous magnetic field in the Gödel-type space-time with potentials. We solve the Klein-Gordon equation subject to a homogeneous magnetic field in a topologically trivial flat class of Gödel-type space-time in the presence of Cornell-type scalar and Coulomb-type vector potentials and analyze the effects on the energy eigenvalues and eigenfunctions.
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48

CEBECI, H., T. DERELI, and R. W. TUCKER. "AUTOPARALLEL ORBITS IN KERR BRANS–DICKE SPACETIMES." International Journal of Modern Physics D 13, no. 01 (January 2004): 137–47. http://dx.doi.org/10.1142/s0218271804004487.

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The bounded orbital motion of a massive spinless test particle in the background of a Kerr Brans–Dicke geometry is analysed in terms of worldlines that are auto-parallels of different metric compatible spacetime connections. In one case the connection is that of Levi–Civita with zero-torsion. In the second case the connection has torsion determined by the gradient of the Brans–Dicke background scalar field. The calculations permit one in principle to discriminate between these possibilities.
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49

Anselmi, Damiano. "Purely Virtual Particles in Quantum Gravity, Inflationary Cosmology and Collider Physics." Symmetry 14, no. 3 (March 3, 2022): 521. http://dx.doi.org/10.3390/sym14030521.

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We review the concept of purely virtual particle and its uses in quantum gravity, primordial cosmology and collider physics. The fake particle, or “fakeon”, which mediates interactions without appearing among the incoming and outgoing states, can be introduced by means of a new diagrammatics. The renormalization coincides with one of the parent Euclidean diagrammatics, while unitarity follows from spectral optical identities, which can be derived by means of algebraic operations. The classical limit of a theory of physical particles and fakeons is described by an ordinary Lagrangian plus Hermitian, micro acausal and micro nonlocal self-interactions. Quantum gravity propagates the graviton, a massive scalar field (the inflaton) and a massive spin-2 fakeon, and leads to a constrained primordial cosmology, which predicts the tensor-to-scalar ratio r in the window 0.4≲1000r≲3.5. The interpretation of inflation as a cosmic RG flow allows us to calculate the perturbation spectra to high orders in the presence of the Weyl squared term. In models of new physics beyond the standard model, fakeons evade various phenomenological bounds, because they are less constrained than normal particles. The resummation of self-energies reveals that it is impossible to get too close to the fakeon peak. The related peak uncertainty, equal to the fakeon width divided by 2, is expected to be observable.
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50

Gottlöber, S., V. Müller, H. J. Haubold, and J. P. Mücket. "Vacuum Polarization and Scalar Field Effects in the Early Universe." Symposium - International Astronomical Union 130 (1988): 515. http://dx.doi.org/10.1017/s0074180900136460.

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Talcing into account vacuum polarization effects and a coherent massive scalar field we consider a singularity free cosmological model from which an intermediate inflationary stage follows quite naturally. According to the ideas of Tryon, Fomin, Zeldovich and others on the spontaneous creation of an universe by a quantum process the newly created universe must be closed. Its evolution starts from a finite initial value a of the order of the Planck length with a zero velocity ho = 0 (h - Hubble parameter). Therefore, in this moment an effective source term not fulfilling the strong energy condition must be dominant. It can originate fron a coherent massive scalar field (mass m) with zero kinetic energy and/or the vacuum polarization (considered here in the form of a modified gravitational Lagrangian with quadratic terms of the Ricci scalar). The corresponding general Lagrangian reads (c = h =1) where ∝ is a negative coupling constant and Lmat is the Lagrangian of other possible existing matter. Both the massive scalar field and the vacuum polarization effects drive the universe to expand exponentially for a definite time interval depending on the initial radius a0 and the parameters m and ∝, during which all other matter being originally present is diluted. The following small oscillations superimposed on the dust-like power law behaviour of the scale factor cause an intensive particle production, and the universe heats up to a radiation dominated Friedmann universe. This process must terminate before baryogenesis. The matching of the different phases of the cosmological evolution and the requirement to fit the parameters of the observed universe lead to a definite parameter range for m and |∝| well below the Planck values. In consequence the present mass density must be equal to the critical one (Ω = 1) with high accuracy.
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