2017 – current Research Scholar at the Institute for Advanced Physical Studies, Sofia Bulgaria and the Ronin Institute for Independent Scholars, Montclair, NJ, USA.2015 – 2017 Visiting Assistant Professor in Physics at the Sichuan University--Pittsburg Institute (SCUPI), Chengdu, China. 2007 – 2015 Physics
Phys. Rev. C63 (2001) 014318 also as arXiv: nucl-th/0009014, 2001
Results of shell-model calculations for lower pf-shell nuclei show that SU(3) symmetry breaking i... more Results of shell-model calculations for lower pf-shell nuclei show that SU(3) symmetry breaking in this region is driven by the single-particle spin-orbit splitting. However, even though states of the yrast band exhibit SU(3) symmetry breaking, the results also show that the yrast band B(E2) values are insensitive to this fragmentation of the SU(3) symmetry; specifically, the quadrupole collectivity as measured by SU(3) transition strengths between low lying members of the yrast band remain high even though SU(3) appears to be broken. Results for 44,46,48 Ti and 48Cr using the Kuo-Brown-3 two-body interaction are given to illustrate these observations.
We discuss modeling of nuclear structure beyond the 2-body interaction paradigm. Our first exampl... more We discuss modeling of nuclear structure beyond the 2-body interaction paradigm. Our first example is related to the need of three nucleon contact interaction terms suggested by chiral perturbation theory. The relationship of the two low-energy effective coupling parameters for the relevant three nucleon contact interaction terms $c_D$ and $c_E$ that reproduce the binding energy of $^3$H and $^3$He has been emphasized and the physically relevant parameter region has been illustrated using the binding energy of $^4$He. Further justification of A-body interaction terms is outlined based on the Okubo-Lee-Suzuki effective interaction method used in solving the nuclear many-body problem within a finite model space. The third example we use is an exactly solvable A-body extended paring interaction applied to heavy nuclei with a long isotopic chains, in particular using $^{132}$Sn and $^{208}$Pb as closed core system illustrates a remarkable relationship between the extended pairing streng...
A natural embedding Am−1⊕An−1 ⊂ Amn−1 for the corresponding quantum algebras is constructed throu... more A natural embedding Am−1⊕An−1 ⊂ Amn−1 for the corresponding quantum algebras is constructed through the appropriate comultiplication on the generators of each of the Am−1 and An−1 algebras. The above embedding is proved in their q-boson realization by means of the isomorphism between the Aq (mn)∼ ⊗ Aq (m)∼ ⊗ Aq (n) algebras. Recently, quite a great interest has been paid to the study of quantum algebras and their applications to physical problems. Essentially quantum algebras are Hopf algebras. Hopf algebra is an algebra with additional structures: i) except the multiplication m : A ⊗ A → A there is a comultiplication ∆ : A → A ⊗ A; ii) except the unit 1 which provides the embedding R → A (C → A), where R (C) is the real (complex) field, there is a counit ε : A → R (C) . All these mappings are homomorphisms and there is an antihomomorphism S : A → A called antipode. From mathematical point of view such algebras were developed much earlier [1, 2]. The contemporary development of thei...
The relativistic particle Lagrangian justifies the importance of Reparametrization-Invariant Syst... more The relativistic particle Lagrangian justifies the importance of Reparametrization-Invariant Systems - in particular, the first-order homogeneous Lagrangians in the velocities. Such systems are studied from the point of view of the Lagrangian and extended Hamiltonian formalism. The extended Hamiltonian formulation is using an extended Poisson bracket that is generally co-variant and applicable to reparametrization-invariant systems. The extended Poisson bracket is defined over the phase-space-time and includes the coordinate time and the energy in a way consistent with the Canonical Quantization formalism. The corresponding extended Hamiltonian $\boldsymbol{H}$ defines the classical phase space-time of the system via the Hamiltonian constraint $\boldsymbol{H}= 0$ and guarantees that the Classical Hamiltonian $H$ corresponds to $p_0$ - the energy of the particle when the parametrization $\lambda = t$ is chosen. When the extended Hamiltonian for a classical system is quantized ($\bold...
The influence of the intruder level on nuclear deformation is studied within the framework of the... more The influence of the intruder level on nuclear deformation is studied within the framework of the nucleon-pair shell model, truncated to an SD-pair subspace. The results suggest that the intruder level has a tendency to reduce the deformation for nuclei in lower and middle shells, and plays an important role in determining the onset of rotational behavior.
Recently it was found from Cassini data that the mean recession speed of Titan from Saturn is v =... more Recently it was found from Cassini data that the mean recession speed of Titan from Saturn is v = 11.3 ± 2.0 cm/yr which corresponds to a tidal quality factor of Saturn Q ≈ 100 while the standard estimate yields Q ≥ 6 · 104 . It was assumed that such a large speed v is due to a resonance locking mechanism of five inner mid-sized moons of Saturn. In this paper, we show that an essential part of v may come from a local Hubble expansion, where the Hubble-Lemaˆıtre constant H0 recalculated to the Saturn-Titan distance D is 8.15 cm/(yrD). Our hypothesis is based on many other observations showing a slight expansion of the Solar system and also of our Galaxy at a rate comparable with H0. We demonstrate that the large disproportion in estimating the Q factor can be just caused by the local expansion effect. [Accepted for publication in "Gravitation and Cosmology". The paper is to appear in Vol. 28, Issue 2 (2022) of the journal Gravitation and Cosmology.]
We present a summary of the main results within the Scale Invariant Vacuum (SIV) paradigm as rela... more We present a summary of the main results within the Scale Invariant Vacuum (SIV) paradigm as related to the Weyl Integrable Geometry (WIG) as an extension to the standard Einstein General Relativity (EGR). After a brief review of the mathematical framework, we will highlight the main results related to inflation within the SIV, the growth of the density fluctuations, and the application of the SIV to scale-invariant dynamics of galaxies, MOND, dark matter, and the dwarf spheroidals. The possible connection between the weak-field SIV equations and the notion of un-proper time parametrization within the reparametrization paradigm is also discussed.
The properties of atomic nuclei far from the line of stability is of major current interest in nu... more The properties of atomic nuclei far from the line of stability is of major current interest in nuclear physics. A factor limiting reliable theoretical calculations in such domains is the size of the valence model space that is required for realistic calculations. This same challenge arises for upper pf-shell nuclei. Using symmetries of the system, one may identify a solvable shell-model scheme that can be used to focus on essential characteristics of the system without requiring full-space calculations that are difficult to carryout and understand. In particular, it has been suggested that pseudo-SU(4) might be relevant symmetry for nuclei beyond ^56Ni. This, in turn, suggests that the pseudo-SU(3) scheme might be a good symmetry for these nuclei. We evaluate the applicability of pseudo-SU(3) in this region by calculating the strength distribution of the second order Casimir operator of pseudo-SU(3) in realistic eigenstates.
Phys. Rev. C63 (2001) 014318 also as arXiv: nucl-th/0009014, 2001
Results of shell-model calculations for lower pf-shell nuclei show that SU(3) symmetry breaking i... more Results of shell-model calculations for lower pf-shell nuclei show that SU(3) symmetry breaking in this region is driven by the single-particle spin-orbit splitting. However, even though states of the yrast band exhibit SU(3) symmetry breaking, the results also show that the yrast band B(E2) values are insensitive to this fragmentation of the SU(3) symmetry; specifically, the quadrupole collectivity as measured by SU(3) transition strengths between low lying members of the yrast band remain high even though SU(3) appears to be broken. Results for 44,46,48 Ti and 48Cr using the Kuo-Brown-3 two-body interaction are given to illustrate these observations.
We discuss modeling of nuclear structure beyond the 2-body interaction paradigm. Our first exampl... more We discuss modeling of nuclear structure beyond the 2-body interaction paradigm. Our first example is related to the need of three nucleon contact interaction terms suggested by chiral perturbation theory. The relationship of the two low-energy effective coupling parameters for the relevant three nucleon contact interaction terms $c_D$ and $c_E$ that reproduce the binding energy of $^3$H and $^3$He has been emphasized and the physically relevant parameter region has been illustrated using the binding energy of $^4$He. Further justification of A-body interaction terms is outlined based on the Okubo-Lee-Suzuki effective interaction method used in solving the nuclear many-body problem within a finite model space. The third example we use is an exactly solvable A-body extended paring interaction applied to heavy nuclei with a long isotopic chains, in particular using $^{132}$Sn and $^{208}$Pb as closed core system illustrates a remarkable relationship between the extended pairing streng...
A natural embedding Am−1⊕An−1 ⊂ Amn−1 for the corresponding quantum algebras is constructed throu... more A natural embedding Am−1⊕An−1 ⊂ Amn−1 for the corresponding quantum algebras is constructed through the appropriate comultiplication on the generators of each of the Am−1 and An−1 algebras. The above embedding is proved in their q-boson realization by means of the isomorphism between the Aq (mn)∼ ⊗ Aq (m)∼ ⊗ Aq (n) algebras. Recently, quite a great interest has been paid to the study of quantum algebras and their applications to physical problems. Essentially quantum algebras are Hopf algebras. Hopf algebra is an algebra with additional structures: i) except the multiplication m : A ⊗ A → A there is a comultiplication ∆ : A → A ⊗ A; ii) except the unit 1 which provides the embedding R → A (C → A), where R (C) is the real (complex) field, there is a counit ε : A → R (C) . All these mappings are homomorphisms and there is an antihomomorphism S : A → A called antipode. From mathematical point of view such algebras were developed much earlier [1, 2]. The contemporary development of thei...
The relativistic particle Lagrangian justifies the importance of Reparametrization-Invariant Syst... more The relativistic particle Lagrangian justifies the importance of Reparametrization-Invariant Systems - in particular, the first-order homogeneous Lagrangians in the velocities. Such systems are studied from the point of view of the Lagrangian and extended Hamiltonian formalism. The extended Hamiltonian formulation is using an extended Poisson bracket that is generally co-variant and applicable to reparametrization-invariant systems. The extended Poisson bracket is defined over the phase-space-time and includes the coordinate time and the energy in a way consistent with the Canonical Quantization formalism. The corresponding extended Hamiltonian $\boldsymbol{H}$ defines the classical phase space-time of the system via the Hamiltonian constraint $\boldsymbol{H}= 0$ and guarantees that the Classical Hamiltonian $H$ corresponds to $p_0$ - the energy of the particle when the parametrization $\lambda = t$ is chosen. When the extended Hamiltonian for a classical system is quantized ($\bold...
The influence of the intruder level on nuclear deformation is studied within the framework of the... more The influence of the intruder level on nuclear deformation is studied within the framework of the nucleon-pair shell model, truncated to an SD-pair subspace. The results suggest that the intruder level has a tendency to reduce the deformation for nuclei in lower and middle shells, and plays an important role in determining the onset of rotational behavior.
Recently it was found from Cassini data that the mean recession speed of Titan from Saturn is v =... more Recently it was found from Cassini data that the mean recession speed of Titan from Saturn is v = 11.3 ± 2.0 cm/yr which corresponds to a tidal quality factor of Saturn Q ≈ 100 while the standard estimate yields Q ≥ 6 · 104 . It was assumed that such a large speed v is due to a resonance locking mechanism of five inner mid-sized moons of Saturn. In this paper, we show that an essential part of v may come from a local Hubble expansion, where the Hubble-Lemaˆıtre constant H0 recalculated to the Saturn-Titan distance D is 8.15 cm/(yrD). Our hypothesis is based on many other observations showing a slight expansion of the Solar system and also of our Galaxy at a rate comparable with H0. We demonstrate that the large disproportion in estimating the Q factor can be just caused by the local expansion effect. [Accepted for publication in "Gravitation and Cosmology". The paper is to appear in Vol. 28, Issue 2 (2022) of the journal Gravitation and Cosmology.]
We present a summary of the main results within the Scale Invariant Vacuum (SIV) paradigm as rela... more We present a summary of the main results within the Scale Invariant Vacuum (SIV) paradigm as related to the Weyl Integrable Geometry (WIG) as an extension to the standard Einstein General Relativity (EGR). After a brief review of the mathematical framework, we will highlight the main results related to inflation within the SIV, the growth of the density fluctuations, and the application of the SIV to scale-invariant dynamics of galaxies, MOND, dark matter, and the dwarf spheroidals. The possible connection between the weak-field SIV equations and the notion of un-proper time parametrization within the reparametrization paradigm is also discussed.
The properties of atomic nuclei far from the line of stability is of major current interest in nu... more The properties of atomic nuclei far from the line of stability is of major current interest in nuclear physics. A factor limiting reliable theoretical calculations in such domains is the size of the valence model space that is required for realistic calculations. This same challenge arises for upper pf-shell nuclei. Using symmetries of the system, one may identify a solvable shell-model scheme that can be used to focus on essential characteristics of the system without requiring full-space calculations that are difficult to carryout and understand. In particular, it has been suggested that pseudo-SU(4) might be relevant symmetry for nuclei beyond ^56Ni. This, in turn, suggests that the pseudo-SU(3) scheme might be a good symmetry for these nuclei. We evaluate the applicability of pseudo-SU(3) in this region by calculating the strength distribution of the second order Casimir operator of pseudo-SU(3) in realistic eigenstates.
The growth of the density fluctuations is considered to be an important cosmological test. In the... more The growth of the density fluctuations is considered to be an important cosmological test. In the standard ΛCDM cosmological model, it is assumed that to form galaxies the baryons settle down in the potential well of dark matter previously assembled during the radiation era of the universe. As such, it has been previously used to infer the presence of dark matter in our universe that is needed to provide the seeds for the formation and growth of the matter inhomogeneities at the recombination epoch and onward until the current epoch. This view is challenged in the present paper by using the recently proposed model of a scale-invariant framework for cosmology that is based on the Weyl conformal geometry. The model has already been shown to be in a position to describe observational data to a level compatible to the standard ΛCDM cosmology model but without the need to invoke dark matter and dark energy. The current paper provides the first application of the scale-invariant framework to the growth of the density fluctuations δ. The equation governing the evolution of δ is derived from the continuity equation, the Euler and Poisson equations written within the scale-invariant framework. Numerical solutions for various background densities are obtained by starting with δ = 10^(−5) at a redshift around z ≈ 10^3. The growth of the density fluctuations is much faster than in the standard EdS model, where the growth of the density perturbations evolves with redshift z like (1/ 1+z)^s with s = 1, which is not fast enough to account for the observed present-day inhomogeneities without invoking dark matter. However, the scale-invariant framework results in values of s from 2.2 to 2.9 for Ω_m between 0.30 and 0.02. This enables the density fluctuations to enter the non-linear regime long before the present time, typically at redshifts of a few tens, without requiring the presence of dark matter.
On Nov. 8th, 2018 I gave a broad overview of the Quantum Computing - its past and present at a lo... more On Nov. 8th, 2018 I gave a broad overview of the Quantum Computing - its past and present at a local Software Developer hub in Modesto - the ValleyWorX. Here is the pdf copy of my slides which is also available form LinkedIn Slides: https://www.slideshare.net/VGGConsultingVGGueor/quantum-computing-history-and-prospects
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https://www.slideshare.net/VGGConsultingVGGueor/quantum-computing-history-and-prospects