TY  - JOUR
AU  - Andreev, V. A.
AU  - Davidović, Dragomir M.
AU  - Davidović, Ljubica D.
AU  - Davidović, Milena D.
AU  - Davidović, Miloš D.
PY  - 2017
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/1685
AB  - We consider scale transformations (q, p) - GT (lambda q, lambda p) in phase space. They induce transformations of the Husimi functions H(q, p) defined in this space. We consider the Husimi functions for states that are arbitrary superpositions of n-particle states of a harmonic oscillator. We develop a method that allows finding so-called stretched states to which these superpositions transform under such a scale transformation. We study the properties of the stretched states and calculate their density matrices in explicit form. We establish that the density matrix structure can be described using negative binomial distributions. We find expressions for the energy and entropy of stretched states and calculate the means of the number-ofstates operator. We give the form of the Heisenberg and Robertson-Schrodinger uncertainty relations for stretched states.
T2  - Theoretical and Mathematical Physics
T1  - Scale Transformations in Phase Space and Stretched States of a Harmonic Oscillator
VL  - 192
IS  - 1
SP  - 1080
EP  - 1096
DO  - 10.1134/S0040577917070091
ER  - 

@article{
author = "Andreev, V. A. and Davidović, Dragomir M. and Davidović, Ljubica D. and Davidović, Milena D. and Davidović, Miloš D.",
year = "2017",
abstract = "We consider scale transformations (q, p) - GT (lambda q, lambda p) in phase space. They induce transformations of the Husimi functions H(q, p) defined in this space. We consider the Husimi functions for states that are arbitrary superpositions of n-particle states of a harmonic oscillator. We develop a method that allows finding so-called stretched states to which these superpositions transform under such a scale transformation. We study the properties of the stretched states and calculate their density matrices in explicit form. We establish that the density matrix structure can be described using negative binomial distributions. We find expressions for the energy and entropy of stretched states and calculate the means of the number-ofstates operator. We give the form of the Heisenberg and Robertson-Schrodinger uncertainty relations for stretched states.",
journal = "Theoretical and Mathematical Physics",
title = "Scale Transformations in Phase Space and Stretched States of a Harmonic Oscillator",
volume = "192",
number = "1",
pages = "1080-1096",
doi = "10.1134/S0040577917070091"
}

Andreev, V. A., Davidović, D. M., Davidović, L. D., Davidović, M. D.,& Davidović, M. D.. (2017). Scale Transformations in Phase Space and Stretched States of a Harmonic Oscillator. in Theoretical and Mathematical Physics, 192(1), 1080-1096.
https://doi.org/10.1134/S0040577917070091

Andreev VA, Davidović DM, Davidović LD, Davidović MD, Davidović MD. Scale Transformations in Phase Space and Stretched States of a Harmonic Oscillator. in Theoretical and Mathematical Physics. 2017;192(1):1080-1096.
doi:10.1134/S0040577917070091 .

Andreev, V. A., Davidović, Dragomir M., Davidović, Ljubica D., Davidović, Milena D., Davidović, Miloš D., "Scale Transformations in Phase Space and Stretched States of a Harmonic Oscillator" in Theoretical and Mathematical Physics, 192, no. 1 (2017):1080-1096,
https://doi.org/10.1134/S0040577917070091 . .

TY  - JOUR
AU  - Andreev, V. A.
AU  - Davidović, Ljubica D.
AU  - Davidović, Milena D.
AU  - Davidović, Miloš D.
AU  - Manko, V. I.
AU  - Manko, M. A.
PY  - 2014
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6033
AB  - We propose a new method for calculating Husimi symbols of operators. In contrast to the standard method, it does not require using the anti-normal-ordering procedure. According to this method, the coordinate and momentum operators (q) over cap and (p) over cap are assigned other operators (X) over cap and (P) over cap satisfying the same commutation relations. We then find the result of acting with the (X) over cap and (P) over cap operators and also polynomials in these operators on the Husimi function. After the obtained expression is integrated over the phase space coordinates, the integrand becomes a Husimi function times the symbol of the operator chosen to act on that function. We explicitly evaluate the Husimi symbols for operators that are powers of (X) over cap or (P) over cap.
T2  - Theoretical and Mathematical Physics
T1  - Operator Method for Calculating Q Symbols and Their Relation to Weyl-Wigner Symbols and Symplectic Tomogram Symbols
VL  - 179
IS  - 2
SP  - 559
EP  - 573
DO  - 10.1007/s11232-014-0162-1
ER  - 

@article{
author = "Andreev, V. A. and Davidović, Ljubica D. and Davidović, Milena D. and Davidović, Miloš D. and Manko, V. I. and Manko, M. A.",
year = "2014",
abstract = "We propose a new method for calculating Husimi symbols of operators. In contrast to the standard method, it does not require using the anti-normal-ordering procedure. According to this method, the coordinate and momentum operators (q) over cap and (p) over cap are assigned other operators (X) over cap and (P) over cap satisfying the same commutation relations. We then find the result of acting with the (X) over cap and (P) over cap operators and also polynomials in these operators on the Husimi function. After the obtained expression is integrated over the phase space coordinates, the integrand becomes a Husimi function times the symbol of the operator chosen to act on that function. We explicitly evaluate the Husimi symbols for operators that are powers of (X) over cap or (P) over cap.",
journal = "Theoretical and Mathematical Physics",
title = "Operator Method for Calculating Q Symbols and Their Relation to Weyl-Wigner Symbols and Symplectic Tomogram Symbols",
volume = "179",
number = "2",
pages = "559-573",
doi = "10.1007/s11232-014-0162-1"
}

Andreev, V. A., Davidović, L. D., Davidović, M. D., Davidović, M. D., Manko, V. I.,& Manko, M. A.. (2014). Operator Method for Calculating Q Symbols and Their Relation to Weyl-Wigner Symbols and Symplectic Tomogram Symbols. in Theoretical and Mathematical Physics, 179(2), 559-573.
https://doi.org/10.1007/s11232-014-0162-1

Andreev VA, Davidović LD, Davidović MD, Davidović MD, Manko VI, Manko MA. Operator Method for Calculating Q Symbols and Their Relation to Weyl-Wigner Symbols and Symplectic Tomogram Symbols. in Theoretical and Mathematical Physics. 2014;179(2):559-573.
doi:10.1007/s11232-014-0162-1 .

Andreev, V. A., Davidović, Ljubica D., Davidović, Milena D., Davidović, Miloš D., Manko, V. I., Manko, M. A., "Operator Method for Calculating Q Symbols and Their Relation to Weyl-Wigner Symbols and Symplectic Tomogram Symbols" in Theoretical and Mathematical Physics, 179, no. 2 (2014):559-573,
https://doi.org/10.1007/s11232-014-0162-1 . .

TY  - JOUR
AU  - Andreev, V. A.
AU  - Davidović, Dragomir M.
AU  - Davidović, Ljubica D.
AU  - Davidović, Milena D.
AU  - Man'ko, V. I.
AU  - Man'ko, M. A.
PY  - 2011
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/4443
AB  - We consider the Husimi Q-functions, which are quantum quasiprobability distributions in the phase space, and investigate their transformation properties under a scale transformation (q, p) - GT (lambda q, lambda p). We prove a theorem that under this transformation, the Husimi function of a physical state is transformed into a function that is also a Husimi function of some physical state. Therefore, the scale transformation defines a positive map of density operators. We investigate the relation of Husimi functions to Wigner functions and symplectic tomograms and establish how they transform under the scale transformation. As an example, we consider the harmonic oscillator and show how its states transform under the scale transformation.
T2  - Theoretical and Mathematical Physics
T1  - A Transformational Property of the Husimi Function and Its Relation to the Wigner Function and Symplectic Tomograms
VL  - 166
IS  - 3
SP  - 356
EP  - 368
DO  - 10.1007/s11232-011-0028-8
ER  - 

@article{
author = "Andreev, V. A. and Davidović, Dragomir M. and Davidović, Ljubica D. and Davidović, Milena D. and Man'ko, V. I. and Man'ko, M. A.",
year = "2011",
abstract = "We consider the Husimi Q-functions, which are quantum quasiprobability distributions in the phase space, and investigate their transformation properties under a scale transformation (q, p) - GT (lambda q, lambda p). We prove a theorem that under this transformation, the Husimi function of a physical state is transformed into a function that is also a Husimi function of some physical state. Therefore, the scale transformation defines a positive map of density operators. We investigate the relation of Husimi functions to Wigner functions and symplectic tomograms and establish how they transform under the scale transformation. As an example, we consider the harmonic oscillator and show how its states transform under the scale transformation.",
journal = "Theoretical and Mathematical Physics",
title = "A Transformational Property of the Husimi Function and Its Relation to the Wigner Function and Symplectic Tomograms",
volume = "166",
number = "3",
pages = "356-368",
doi = "10.1007/s11232-011-0028-8"
}

Andreev, V. A., Davidović, D. M., Davidović, L. D., Davidović, M. D., Man'ko, V. I.,& Man'ko, M. A.. (2011). A Transformational Property of the Husimi Function and Its Relation to the Wigner Function and Symplectic Tomograms. in Theoretical and Mathematical Physics, 166(3), 356-368.
https://doi.org/10.1007/s11232-011-0028-8

Andreev VA, Davidović DM, Davidović LD, Davidović MD, Man'ko VI, Man'ko MA. A Transformational Property of the Husimi Function and Its Relation to the Wigner Function and Symplectic Tomograms. in Theoretical and Mathematical Physics. 2011;166(3):356-368.
doi:10.1007/s11232-011-0028-8 .

Andreev, V. A., Davidović, Dragomir M., Davidović, Ljubica D., Davidović, Milena D., Man'ko, V. I., Man'ko, M. A., "A Transformational Property of the Husimi Function and Its Relation to the Wigner Function and Symplectic Tomograms" in Theoretical and Mathematical Physics, 166, no. 3 (2011):356-368,
https://doi.org/10.1007/s11232-011-0028-8 . .

TY  - JOUR
AU  - Andreev, V. A.
AU  - Davidović, Dragomir M.
AU  - Davidović, Ljubica D.
AU  - Davidović, Milena D.
PY  - 2011
UR  - https://vinar.vin.bg.ac.rs/handle/123456789/6898
AB  - Husimi Q-functions are the only functions from the class of Cohen quasi-distributions on phase space that after scaling transformation (q, p) - GT (lambda q, lambda p) remain in the same class when the modulus of the scaling parameter is smaller than unity and so, in this case, describe a physical state. We found the Wigner functions and symplectic tomograms of such states. We applied the obtained general results to the Fock states of the harmonic oscillator.
T2  - Physica Scripta
T1  - Relations between scaling-transformed Husimi functions, Wigner functions and symplectic tomograms describing corresponding physical states
VL  - T143
DO  - 10.1088/0031-8949/2011/T143/014003
ER  - 

@article{
author = "Andreev, V. A. and Davidović, Dragomir M. and Davidović, Ljubica D. and Davidović, Milena D.",
year = "2011",
abstract = "Husimi Q-functions are the only functions from the class of Cohen quasi-distributions on phase space that after scaling transformation (q, p) - GT (lambda q, lambda p) remain in the same class when the modulus of the scaling parameter is smaller than unity and so, in this case, describe a physical state. We found the Wigner functions and symplectic tomograms of such states. We applied the obtained general results to the Fock states of the harmonic oscillator.",
journal = "Physica Scripta",
title = "Relations between scaling-transformed Husimi functions, Wigner functions and symplectic tomograms describing corresponding physical states",
volume = "T143",
doi = "10.1088/0031-8949/2011/T143/014003"
}

Andreev, V. A., Davidović, D. M., Davidović, L. D.,& Davidović, M. D.. (2011). Relations between scaling-transformed Husimi functions, Wigner functions and symplectic tomograms describing corresponding physical states. in Physica Scripta, T143.
https://doi.org/10.1088/0031-8949/2011/T143/014003

Andreev VA, Davidović DM, Davidović LD, Davidović MD. Relations between scaling-transformed Husimi functions, Wigner functions and symplectic tomograms describing corresponding physical states. in Physica Scripta. 2011;T143.
doi:10.1088/0031-8949/2011/T143/014003 .

Andreev, V. A., Davidović, Dragomir M., Davidović, Ljubica D., Davidović, Milena D., "Relations between scaling-transformed Husimi functions, Wigner functions and symplectic tomograms describing corresponding physical states" in Physica Scripta, T143 (2011),
https://doi.org/10.1088/0031-8949/2011/T143/014003 . .