| |
Records |
Links |
|
Author |
Blanes, S.; Casas, F.; Oteo, J.A.; Ros, J. |
|
| |
Title |
A pedagogical approach to the Magnus expansion |
Type |
Journal Article |
| |
Year |
2010 |
Publication |
European Journal of Physics |
Abbreviated Journal |
Eur. J. Phys. |
|
| |
Volume |
31 |
Issue |
4 |
Pages  |
907-918 |
|
| |
Keywords |
|
|
| |
Abstract |
Time-dependent perturbation theory as a tool to compute approximate solutions of the Schrodinger equation does not preserve unitarity. Here we present, in a simple way, how the Magnus expansion (also known as exponential perturbation theory) provides such unitary approximate solutions. The purpose is to illustrate the importance and consequences of such a property. We suggest that the Magnus expansion may be introduced to students in advanced courses of quantum mechanics. |
|
| |
Address |
[Blanes, S.] Univ Politecn Valencia, Inst Matemat Multidisciplinar, E-46022 Valencia, Spain, Email: serblaza@imm.upv.es |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Iop Publishing Ltd |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0143-0807 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
ISI:000279393800024 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
no |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
259 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Casas, F.; Oteo, J.A.; Ros, J. |
|
| |
Title |
Unitary transformations depending on a small parameter |
Type |
Journal Article |
| |
Year |
2012 |
Publication |
Proceedings of the Royal Society A |
Abbreviated Journal |
Proc. R. Soc. A |
|
| |
Volume |
468 |
Issue |
2139 |
Pages |
685-700 |
|
| |
Keywords |
perturbation theory; quantum mechanics; unitary transformation; Magnus expansion |
|
| |
Abstract |
We formulate a unitary perturbation theory for quantum mechanics inspired by the Lie-Deprit formulation of canonical transformations. The original Hamiltonian is converted into a solvable one by a transformation obtained through a Magnus expansion. This ensures unitarity at every order in a small parameter. A comparison with the standard perturbation theory is provided. We work out the scheme up to order ten with some simple examples. |
|
| |
Address |
[Oteo, J. A.; Ros, J.] Univ Valencia, Dept Fis Teor, E-46100 Valencia, Spain, Email: rosj@uv.es |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Royal Soc |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1364-5021 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000300185400005 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
no |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
893 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Botella-Soler, V.; Oteo, J.A.; Ros, J. |
|
| |
Title |
Coexistence of periods in a bifurcation |
Type |
Journal Article |
| |
Year |
2012 |
Publication |
Chaos, Solitons & Fractals |
Abbreviated Journal |
Chaos Solitons Fractals |
|
| |
Volume |
45 |
Issue |
5 |
Pages |
681-686 |
|
| |
Keywords |
|
|
| |
Abstract |
A particular type of order-to-chaos transition mediated by an infinite set of coexisting neutrally stable limit cycles of different periods is studied in the Varley-Gradwell-Hassell population model. We prove by an algebraic method that this kind of transition can only happen for a particular bifurcation parameter value. Previous results on the structure of the attractor at the transition point are here simplified and extended. |
|
| |
Address |
[Botella-Soler, V.; Oteo, J. A.; Ros, J.] Univ Valencia, Dept Fis Teor, E-46100 Valencia, Spain, Email: vicente.botella@uv.es |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Pergamon-Elsevier Science Ltd |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
0960-0779 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000303785300014 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
no |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
1005 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Baeza-Ballesteros, J.; Donini, A.; Molina-Terriza, G.; Monrabal, F.; Simon, A. |
|
| |
Title |
Towards a realistic setup for a dynamical measurement of deviations from Newton's 1/r2 law: the impact of air viscosity |
Type |
Journal Article |
| |
Year |
2024 |
Publication |
European Physical Journal C |
Abbreviated Journal |
Eur. Phys. J. C |
|
| |
Volume |
84 |
Issue |
6 |
Pages |
596 - 20pp |
|
| |
Keywords |
|
|
| |
Abstract |
A novel experimental setup to measure deviations from the 1/r(2) distance dependence of Newtonian gravity was proposed in Donini and Marimon (Eur Phys J C 76:696, 2016). The underlying theoretical idea was to study the orbits of a microscopically-sized planetary system composed of a “Satellite”, with mass m(S) similar to O(10-9) g, and a “Planet”, with mass M-P similar to O(10-5) g at an initial distance of hundreds of microns. The detection of precession of the orbit in this system would be an unambiguous indication of a central potential with terms that scale with the distance differently from 1/r. This is a huge advantage with respect to the measurement of the absolute strength of the attraction between two bodies, as most electrically-induced background potentials do indeed scale as 1/r. Detection of orbit precession is unaffected by these effects, allowing for better sensitivities. In Baeza-Ballesteros et al. (Eur Phys J C 82:154, 2022), the impact of other subleading backgrounds that may induce orbit precession, such as, e.g., the electrical Casimir force or general relativity, was studied in detail. It was found that the proposed setup could test Yukawa-like corrections, alpha x exp(-r/lambda), to the 1/r potential with couplings as low as alpha similar to 10(-2) for distances as small as lambda similar to 10 μm, improving by roughly an order of magnitude present bounds. In this paper, we start to move from a theoretical study of the proposal to a more realistic implementation of the experimental setup. As a first step, we study the impact of air viscosity on the proposed setup and see how the setup should be modified in order to preserve the theoretical sensitivity achieved in Donini and Marimon (2016) and Baeza-Ballesteros et al. (2022). |
|
| |
Address |
[Baeza-Ballesteros, J.; Donini, A.] Univ Valencia, Inst Fis Corpuscular, CSIC, Calle Catedrat Jose Beltran Martinez 2, Paterna 46980, Spain, Email: jorge.baeza@ific.uv.es |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Springer |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1434-6044 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:001243830900015 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
6156 |
|
| Permanent link to this record |
| |
|
| |
|
Author |
Baeza-Ballesteros, J.; Bijnens, J.; Husek, T.; Romero-Lopez, F.; Sharpe, S.R.; Sjo, M. |
|
| |
Title |
The isospin-3 three-particle K-matrix at NLO in ChPT |
Type |
Journal Article |
| |
Year |
2023 |
Publication |
Journal of High Energy Physics |
Abbreviated Journal |
J. High Energy Phys. |
|
| |
Volume |
05 |
Issue |
5 |
Pages |
187 - 56pp |
|
| |
Keywords |
Chiral Lagrangian; Hadronic Spectroscopy; Structure and Interactions; Lattice QCD |
|
| |
Abstract |
The three-particle K-matrix, K-df,K-3, is a scheme-dependent quantity that parametrizes short-range three-particle interactions in the relativistic-field-theory three particle finite-volume formalism. In this work, we compute its value for systems of three pions at maximal isospin through next-to-leading order (NLO) in Chiral Perturbation Theory (ChPT). We compare the values to existing lattice QCD results and find that the agreement between lattice QCD data and ChPT in the first two coefficients of the threshold expansion of K-df,K-3 is significantly improved with respect to leading order once NLO effects are incorporated. |
|
| |
Address |
[Baeza-Ballesteros, Jorge] Univ Valencia, IFIC, CSIC, Paterna 46980, Spain, Email: jorge.baeza@ific.uv.es; |
|
| |
Corporate Author |
|
Thesis |
|
|
| |
Publisher |
Springer |
Place of Publication |
|
Editor |
|
|
| |
Language |
English |
Summary Language |
|
Original Title |
|
|
| |
Series Editor |
|
Series Title |
|
Abbreviated Series Title |
|
|
| |
Series Volume |
|
Series Issue |
|
Edition |
|
|
| |
ISSN |
1029-8479 |
ISBN |
|
Medium |
|
|
| |
Area |
|
Expedition |
|
Conference |
|
|
| |
Notes |
WOS:000994292300001 |
Approved |
no |
|
| |
Is ISI |
yes |
International Collaboration |
yes |
|
| |
Call Number |
IFIC @ pastor @ |
Serial |
5540 |
|
| Permanent link to this record |
