Pith. sign in

REVIEW 3 major objections 4 minor 1 cited by

A Bogomol'nyi-Prasad-Sommerfield bound with a first-order system in the $2D$ Gross-Pitaevskii equation

T0 review · 3 major / 4 minor · reviewed 2026-08-10 · deepseek-v4-flash

Pith's one-line read Static 2D Gross-Pitaevskii equation admits a BPS bound whose first-order system yields fractional-vorticity solutions.

desk verdict The BPS bound and first-order system for the 2D GPE are real and correct, but the flagship 'fractional vorticity in an annulus' solutions are multi-valued on the annulus and should be framed as cone/cover solutions. read the letter →

arxiv 2501.04092 v4 pith:F6Z2M6ED submitted 2025-01-07 cond-mat.quant-gas hep-phhep-thnlin.SInucl-th

classification cond-mat.quant-gashep-phhep-thnlin.SInucl-th MSC 35Q55 PACS 03.75.Lm
keywords Bogomol'nyi-Prasad-SommerfieldboundGross-Pitaevskiiequationfractionalvorticityfirst-orderBPSsystemtopologicalchargesuperfluidityannularcondensateamplitude-phaserelation
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The reading

The paper's central claim is that the static two-dimensional Gross-Pitaevskii equation (GPE), contrary to the common assumption, admits a Bogomol'nyi-Prasad-Sommerfield (BPS) bound. The energy $E$ can be written as the integral of two non-negative squares plus two boundary terms $Q_1$ and $Q_2$, so $E\ge Q_1+Q_2$; here $Q_1$ is the condensate-dressed circulation and $Q_2$ is a new 'skewness' charge. Setting the square terms to zero yields a first-order BPS system whose solutions automatically satisfy the second-order GPE. From this system the authors construct analytic solutions with phase winding $2\pi/3$, i.e. fractional vorticity $1/3$, living on an annulus, and they present these as the first analytic fractional-vorticity configurations in the GPE. What makes this valuable is that exact solutions and energy bounds of this kind are rare tools for non-perturbative superfluid physics.

What carries the argument

The load-bearing object is the sum-of-squares energy identity (8), whose zero-square conditions define the first-order BPS system (13)--(14). The identity is completed by two boundary charges: $Q_1=(\hbar^2/M)\int_\Gamma d\phi_1\wedge d\phi_2$, the vorticity dressed by the condensate profile, and $Q_2=(\hbar^2\kappa/\sqrt{2}M)\oint_{\partial\Gamma}\hat n\cdot\vec J\,ds$, the flux of the cubic current $(J_x,J_y)=\frac{1}{3}(\mathrm{Re}(\phi_1+i\phi_2)^3,\mathrm{Im}(\phi_1+i\phi_2)^3)$, which measures the configuration's skewness. In amplitude-phase variables the BPS system becomes two first-order equations for $(\rho,S)$; their compatibility yields the master relation $\Delta S=\sqrt{2}\rho[\cos(3S-\gamma-\theta)\partial_r S+\sin(3S-\gamma-\theta)r^{-1}\partial_\theta S]$, which reduces the GPE's two unknown functions to one. The same machinery, with cubic combinations replaced by appropriate degree-three polynomials, produces the sixth-order generalization.

What would settle it

Integrate the energy identity (8) for the explicit solution (31) over the annulus and compare the two sides. A nonzero difference, or a divergence of $E$, $Q_1$, or $Q_2$ as the outer radius approaches the zero of $2\sqrt{2}A\,r^{1/3}-3\kappa r$, would falsify the claim that the first-order system yields finite-energy saturated configurations. As a second check, test whether the phase $S=\theta/3$ can be consistently extended across the branch cut on a cone or Riemann surface without violating the GPE.

Watch

Extended reading notes

Core claim

The central discovery is a BPS reformulation of the static GPE with $V=\mu=0$. For the two real components $\phi_1,\phi_2$ of the condensate, the energy identity $$E=\frac{\$hbar^{2}$}{2M}\int_\Gamma \left[(\partial_x\phi_1+\partial_y\phi_2+A)^2+(\partial_y\phi_1-\partial_x\phi_2+B)^2\right]+Q_1+Q_2$$ holds with $A=\frac{\kappa}{\sqrt{2}}(\phi_2^2-\phi_1^2)$ and $B=-\sqrt{2}\kappa\phi_1\phi_2$, so the energy is bounded below by $Q_1+Q_2$. The first-order system obtained by zeroing the two squares actually implies the second-order GPE system (6). The authors derive explicit solutions: a $1/3$-fractional-vorticity configuration on an annulus, with amplitude $\rho(r)=2\sqrt{2}/(2\sqrt{2}A\,r^{1/3}-3\kappa r)$ and phase $S=\theta/3+\theta_0$, and a domain-wall solution with constant phase. They also show the same construction works for a sixth-order interaction, where the winding fraction becomes $1/4$, and they derive a master amplitude-phase relation (41) valid for all BPS solutions.

Load-bearing premise

The load-bearing premise is that a condensate whose phase winds by $2\pi/3$ is an admissible configuration: the paper itself notes such a phase is not single-valued in a plane and must live on an annulus, cone, or Riemann surface, with the boundary charges $Q_1+Q_2$ finite there.

Editorial extensions

If this is right

  • Because the square terms in the energy identity are non-negative, any BPS solution is an energy minimizer in its topological sector, with energy exactly $Q_1+Q_2$.
  • The static GPE can be attacked through a first-order system, which is numerically and analytically simpler than the second-order equations and opens a route to multi-vortex constructions.
  • Fractional vorticity arises from the cubic nonlinearity alone, without extra fields or interactions, as long as the phase lives on an annulus, a cone, or a Riemann surface.
  • The master amplitude-phase relation reduces the two unknown functions of the GPE to one, so multi-soliton configurations can be sought by solving a single scalar equation for the phase.
  • The hydrodynamical form of the BPS equations ties radial superfluid velocity to angular density gradients, giving exact statements about superflow in these configurations.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • If the BPS system is a genuine zero-curvature condition, as the paper's comparison with non-Abelian connections suggests, integrable-system methods could build multi-vortex superpositions whose low-energy motion follows geodesics on a moduli space.
  • The rational winding fractions tied to interaction power ($1/3$ for cubic, $1/4$ for sixth-order) imply a general rule: choosing the degree of the nonlinearity should select the fractional vorticity, which could be checked by direct substitution for other powers.
  • An annular trap with pure cubic interactions might be a laboratory test: if fractional-winding states are stable, the measured circulation around the ring would be $2\pi/3$ rather than $2\pi$.
  • The charge $Q_2$ offers a time-dependent diagnostic for two-dimensional quantum turbulence: tracking its value would reveal when the cubic current develops sources inside the region, something the usual circulation $Q_1$ alone cannot see.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

3 major / 4 minor

Summary. The paper derives an energy identity for the static two-dimensional Gross-Pitaevskii equation with no potential or chemical potential, rewriting the energy as a sum of two positive squares plus two boundary terms Q1 and Q2. It then observes that setting the squares to zero gives a first-order BPS system whose smooth solutions satisfy the second-order GPE. Two explicit solutions are presented: a radially symmetric amplitude with phase S=θ/3, claimed to be a fractional-vorticity configuration on an annulus, and a domain-wall solution with constant phase. The paper also generalizes the construction to a sextic interaction, gives charge formulas, and derives an amplitude-phase relation.

Significance. The BPS identity and the implication (13)-(14) imply (6) are correct and constitute a genuine and useful reformulation of the static GPE; the paper also correctly identifies the need for dressed, rather than bare, topological charges. The generalized first-order system and the amplitude-phase equation (62) are clean consequences of the construction. However, the advertised explicit fractional-vorticity solution is not a single-valued function on a flat annulus, and the plotted amplitude diverges at the outer radius; these are load-bearing defects because the abstract and conclusions advertise the first analytic fractional-vorticity solutions in an annulus. With the solution moved to a cone or covering space and with the claims adjusted accordingly, the framework would retain substantial value.

major comments (3)
  1. [Section 4.1, Eq. (31)] The field Φ=ρe^{iS} with S=θ/3 is not single-valued on an annulus, since θ and θ+2π label the same point but the phase changes by 2π/3. Consequently φ1 and φ2 are discontinuous across any branch cut, the second derivatives in (6) acquire distributional terms localized on the cut, and (31) is not a solution of the BPS system (13)-(14) or of the GPE (6) on a flat annulus. The paper's own caveat in Section 4.1 that such configurations 'cannot appear in isolation in a two-dimensional plane' and require a cone or Riemann surface confirms this. The abstract's claim of 'fractional vorticity living in an annulus' and the conclusion's claim of 'first analytic examples... defined within an annulus' are therefore not supported by the construction as stated.
  2. [Section 4.1, Eq. (33) and Figure 1] The denominator 2√2 A r^{1/3} - 3κ r vanishes at r=(2√2 A/(3κ))^{3/2} for κ>0, A>0. For the parameters A=1, κ=1 used in Figure 1, this pole is at r≈0.915, so the outer radius R≈0.91 shown in the figure is essentially at the divergence. At that radius ρ, Q1 in (34), and Q2 in (36) are singular, and the assertion that the solution is regular on [R1,R2] is false for the plotted configuration. The paper must either restrict R2 strictly below the pole and state the resulting interval, or explain why an infinite-energy limiting configuration is admissible.
  3. [Section 4, Eqs. (34)-(36)] The topological charge formulas are evaluated for the multi-valued phase S=θ/3 without accounting for the branch cut. The definitions (10) are integrals of total derivatives over a domain on which the fields are assumed smooth; for a discontinuous field those integrals are not well-defined, and the displayed boundary expressions do not follow from (29)-(30) unless an additional contribution along the cut is included. The energy-balance statement E=Q1+Q2 for the explicit solution therefore requires a separate derivation on the cone or covering space where the field is single-valued.
minor comments (4)
  1. [Abstract and Section 6] The wording 'living in an annulus' should be changed to 'on a cone or three-fold cover' (or accompanied by a proof that a flat-annulus interpretation is valid despite the branch cut).
  2. [Figure 1 and surrounding text] Specify that R must be chosen below the pole of (33); the current caption labels R≈0.91 as if it were a regular outer radius.
  3. [Section 2.1] The text 'bΘ1 and bΘ1' should read 'bΘ1 and bΘ2'; the definition g_eff=κ in the line after Eq. (20) is inconsistent with κ²=g_eff used elsewhere and should be clarified.
  4. [Section 4.2 and Figure 3] The text uses 3S0−γ=π/4, while the captions of Figure 3 state 3S0+γ=π/4; the sign convention should be made consistent.

Circularity Check

0 steps flagged · score 0.0 of 10

No circular derivation: the BPS identity is an explicit completion of squares and the first-order system is checked independently; the multi-valued phase concern is a correctness issue, not a circular one.

full rationale

The central identity (8) is an explicit completion of squares with A and B defined in Eq. (9), so the bound E ≥ Q1 + Q2 is a written-out algebraic identity rather than a quantity fitted to the desired result. The implication that the first-order system (13)–(14) implies the second-order system (6) is verified in Appendix A by differentiating the BPS equations and does not presuppose Eq. (6). The explicit solutions (31) and (38) are produced by inserting the phase ansatz into the first-order system and solving an ODE for u = 1/ρ; no parameter is fitted to the energy, to Q1, or to Q2, and the “first analytic examples” claim is an interpretation of the resulting phase profile rather than a restatement of an input. The self-citations [36], [37], and [39] are used only as motivational analogies or as pointers to generalizations, not as load-bearing justifications for the present derivation. The objection that solution (31) has S(θ + 2π) = S(θ) + 2π/3 and is therefore multi-valued on a flat annulus, and that the denominator in (33) can vanish, is a substantive correctness and admissibility concern for the physical application, but it is not circular: the algebraic BPS identity and the implication (13)–(14) ⇒ (6) would remain exactly as written even if the explicit solution were rejected.

Assumptions & free parameters 1 free parameters · 5 assumptions · 2 invented entities

The derivation is self-contained and does not fit parameters to external data. The main additional assumptions are the restriction to V=μ=0 static GPE, the acceptance of multi-valued phases, and the treatment of divergent boundary amplitudes as legitimate configurations.

free parameters (1)
  • Radial integration constant A = Chosen as 1 in the figures
    Integration constant setting the radial scale of the solution; not determined by the equations, chosen by hand to make the amplitude positive on the annulus.
assumptions (5)
  • domain assumption Static, potential-free, zero-chemical-potential GPE (Eq. 3) is taken as the system of interest.
    The BPS bound is derived only for this restricted case, not the general trapped GPE, which limits applicability.
  • standard math The square-completion identity Eq. (8) is asserted as a direct computation.
    Algebraically verifiable by expanding the squares; no external input.
  • standard math Solutions of the first-order BPS system (13)-(14) satisfy the second-order GPE (6).
    Demonstrated by differentiation and substitution; can be checked independently.
  • ad hoc to paper The multi-valued phase S=θ/3 defines a valid configuration on an annulus or cone.
    Standard condensate wavefunctions must be single-valued; the paper accepts a branch cut and a conical geometry without further physical justification.
  • ad hoc to paper Divergent amplitude at the annulus boundary is an acceptable solution feature.
    The solution (31) diverges at the outer radius shown in Figure 1, but the paper still calls it regular and computes boundary charges; this is an unstated assumption about how to handle singular boundaries.
invented entities (2)
  • Dressed vorticity charge Q1
    purpose: First boundary term in the BPS lower bound, equal to the integral of dρ∧dS; reduces to ordinary vorticity when ρ is constant at the boundary.
    A profile-weighted circulation, not the standard quantized vorticity; no independent measurement proposed.
  • Skewness charge Q2
    purpose: Second boundary term in the BPS lower bound, measuring the divergence of the cubic vector current J; interpreted as the skewness of the configuration.
    New charge introduced in this paper; no independent verification outside the theoretical construction.

how reviews work

0 comments
Cite this review

Pith. "Pith review of A Bogomol'nyi-Prasad-Sommerfield bound with a first-order system in the $2D$ Gross-Pitaevskii equation." pith.science (2026). https://pith.science/paper/F6Z2M6ED

@misc{pith2026250104092,
  author       = {Pith},
  title        = {Pith review of: A Bogomol'nyi-Prasad-Sommerfield bound with a first-order system in the $2D$ Gross-Pitaevskii equation},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/F6Z2M6ED}},
  note         = {Machine review of arXiv:2501.04092}
}
read the original abstract

A novel Bogomol'nyi-Prasad-Sommerfield (BPS) bound for the Gross-Pitaevskii equations in two spatial dimensions is presented. The energy can be bounded from below in terms of the combination of two boundary terms, one related to the vorticity (but ``dressed'' by the condensate profile) and the second to the ``skewness'' of the configurations. The bound is saturated by configurations that satisfy a system of two first-order partial differential equations. When such a BPS system is satisfied, the Gross-Pitaevskii equations are also satisfied. The analytic solutions of this BPS system in the present manuscript represent configurations with fractional vorticity living in an annulus. Using these techniques, we present the first analytic examples of this kind. The hydrodynamical interpretation of the BPS system is discussed, and the implications of these results are outlined.

Figures

Figures reproduced from arXiv: 2501.04092 by the authors.

Figure 1
Figure 1. The profile ρ vs. the radial coordinate r for the fractional vorticity solution found with BPS bounds. We took κ = 1 and A = 1, and internal radius a = 0.3 (red dot) while the external one is R ≈ 0.91 (dark-green dot) in arbitrary units. surface as it happens in the cases of defects with angular excess living on surfaces with negative intrinsic curvature (see [57] and references therein). These kinds of defects are … view at source ↗
Figure 2
Figure 2. Level curves for solution (31). We took κ = 1 and A = 1, and internal radius a = 0.3 while the external one is R ≈ 0.91 in arbitrary units. For the solution defined above, the two boundary terms Q1 and Q2 contributing to the topo￾logical charge can be computed explicitly. Taking into account Eq. (29) for S0 = 0, in an annulus one gets Q1 = − ℏ 2 M Z 2π 0 ρ 2 cos2 S ∂θS dθ = − (8π + 3√ 3) ℏ 2 3M(2 √ 2 A R1 3 − 3κ R) … view at source ↗
Figure 3
Figure 3. The profile ρ vs. the radial coordinate r for the second solution found with BPS bounds. We took A = 0, κ = 1, and 3S0 + γ = π 4 . The profile was taken such that the points closer than a ≈ 0.05 to the line x + y = 0 were excluded. -3 -2 -1 0 1 2 3 -3 -2 -1 0 1 2 3 x y [PITH_FULL_IMAGE:figures/full_fig_p011_3.png] view at source ↗
Figures from the paper (1 more)
Figure 4
Figure 4. Figure 4: The vector plot of J⃗, where it is always perpendicular to the line √ 2 A − κ (x cos (3S0 − γ) + y sin (3S0 − γ)) = 0. In this case, A = 0, κ = 1 and 3S0 + γ = π 4 . 5 Amplitude-phase Relation Besides the construction of the exact solutions of GPE described in the prev…

Discussion (0). Continue with ORCID to comment.

Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score. Full citation record

  1. Fractional vorticity, Bogomol'nyi-Prasad-Sommerfield systems and complex structures for the (generalized) spinor Gross-Pitaevskii equations

    cond-mat.quant-gas 2025-02 reject novelty 6.0 of 10

    First-order BPS systems and explicit fractional-vorticity solutions are derived for generalized 2D Gross-Pitaevskii equations with fifth- and sixth-order self-interactions.

Reference graph

Works this paper leans on

63 extracted references · 22 canonical work pages · cited by 1 Pith paper

  1. [39]

    Fractional vorticity, Bogomol’nyi-Prasad-Sommerfield systems and complex structures for the (generalized) spinor Gross-Pitaevskii equations,

    F. Canfora and P. Pais, “Fractional vorticity, Bogomol’nyi-Prasad-Sommerfield systems and complex structures for the (generalized) spinor Gross-Pitaevskii equations,”Nucl. Phys. B 1017(2025) 116955,arXiv:2502.00578 [cond-mat.quant-gas]

  2. [1]

    Pitaevskii and S

    L. Pitaevskii and S. Stringari,Bose-Einstein Condensation and Superfluidity. International Series of Monographs on Physics. OUP Oxford, 2016. https://books.google.cl/books?id=yHByCwAAQBAJ

  3. [2]

    Barenghi and N

    C. Barenghi and N. Parker,A Primer on Quantum Fluids. SpringerBriefs in Physics. Springer International Publishing, 2016. https://books.google.cl/books?id=qi3RDAAAQBAJ

  4. [3]

    Theory of Bose-Einstein condensation in trapped gases,

    F. Dalfovo, S. Giorgini, L. P. Pitaevskii, and S. Stringari, “Theory of Bose-Einstein condensation in trapped gases,”Rev. Mod. Phys.71(1999) 463–512, arXiv:cond-mat/9806038

  5. [4]

    Nobel Lecture: Bose-Einstein condensation in a dilute gas, the first 70 years and some recent experiments,

    E. A. Cornell and C. E. Wieman, “Nobel Lecture: Bose-Einstein condensation in a dilute gas, the first 70 years and some recent experiments,”Rev. Mod. Phys.74(2002) 875–893

  6. [5]

    Nobel lecture: When atoms behave as waves: Bose-Einstein condensation and the atom laser,

    W. Ketterle, “Nobel lecture: When atoms behave as waves: Bose-Einstein condensation and the atom laser,”Rev. Mod. Phys.74(2002) 1131–1151

  7. [6]

    Spinor bose gases: Symmetries, magnetism, and quantum dynamics,

    D. M. Stamper-Kurn and M. Ueda, “Spinor bose gases: Symmetries, magnetism, and quantum dynamics,”Rev. Mod. Phys.85(Jul, 2013) 1191–1244. https://link.aps.org/doi/10.1103/RevModPhys.85.1191

  8. [7]

    Vortices in multicomponent bose–einstein condensates,

    K. Kasamatsu, M. Tsubota, and M. Ueda, “Vortices in multicomponent bose–einstein condensates,”International Journal of Modern Physics B19no. 11, (Apr., 2005) 1835–1904. http://dx.doi.org/10.1142/S0217979205029602

Show all 63 references
  1. [8]

    Classification of the ground states and topological defects in a rotating two-component bose-einstein condensate,

    P. Mason and A. Aftalion, “Classification of the ground states and topological defects in a rotating two-component bose-einstein condensate,”Phys. Rev. A84(Sep, 2011) 033611. https://link.aps.org/doi/10.1103/PhysRevA.84.033611

  2. [9]

    Leggett,Quantum Liquids: Bose condensation and Cooper pairing in condensed-matter systems

    A. Leggett,Quantum Liquids: Bose condensation and Cooper pairing in condensed-matter systems. Oxford Graduate Texts. OUP Oxford, 2006. https://books.google.cl/books?id=HnlPAwAAQBAJ

  3. [10]

    Schmitt,Introduction to Superfluidity: Field-theoretical Approach and Applications

    A. Schmitt,Introduction to Superfluidity: Field-theoretical Approach and Applications. Lecture Notes in Physics. Springer International Publishing, 2014. https://books.google.cl/books?id=vtQlBAAAQBAJ

  4. [11]

    Pethick and H

    C. Pethick and H. Smith,Bose–Einstein Condensation in Dilute Gases. Cambridge University Press, 2008.https://books.google.cl/books?id=G8kgAwAAQBAJ. 18

  5. [12]

    Barenghi, R

    C. Barenghi, R. Donnelly, and W. Vinen,Quantized Vortex Dynamics and Superfluid Turbulence. Lecture Notes in Physics. Springer Berlin Heidelberg, 2001. https://books.google.cl/books?id=GBIgF9X56_oC

  6. [13]

    Colloquium: Supersolids: What and where are they?

    M. Boninsegni and N. V. Prokof’ev, “Colloquium: Supersolids: What and where are they?” Rev. Mod. Phys.84(May, 2012) 759–776. https://link.aps.org/doi/10.1103/RevModPhys.84.759

  7. [14]

    The enigma of supersolidity,

    S. Balibar, “The enigma of supersolidity,”Nature464no. 7286, (Mar, 2010) 176–182. https://doi.org/10.1038/nature08913

  8. [15]

    What makes a crystal supersolid?

    N. Prokof’ev, “What makes a crystal supersolid?”Advances in Physics56no. 2, (2007) 381–402,https://doi.org/10.1080/00018730601183025. https://doi.org/10.1080/00018730601183025

  9. [16]

    Saga of superfluid solids,

    V. I. Yukalov, “Saga of superfluid solids,”Physics2no. 1, (2020) 49–66. https://www.mdpi.com/2624-8174/2/1/6

  10. [17]

    Observation of a dipolar quantum gas with metastable supersolid properties,

    L. Tanzi, E. Lucioni, F. Fam` a, J. Catani, A. Fioretti, C. Gabbanini, R. N. Bisset, L. Santos, and G. Modugno, “Observation of a dipolar quantum gas with metastable supersolid properties,”Phys. Rev. Lett.122(Apr, 2019) 130405. https://link.aps.org/doi/10.1103/PhysRevLett.122.130405

  11. [18]

    Transient supersolid properties in an array of dipolar quantum droplets,

    F. B¨ ottcher, J.-N. Schmidt, M. Wenzel, J. Hertkorn, M. Guo, T. Langen, and T. Pfau, “Transient supersolid properties in an array of dipolar quantum droplets,”Phys. Rev. X9 (Mar, 2019) 011051.https://link.aps.org/doi/10.1103/PhysRevX.9.011051

  12. [19]

    Long-lived and transient supersolid behaviors in dipolar quantum gases,

    L. Chomaz, D. Petter,et al., “Long-lived and transient supersolid behaviors in dipolar quantum gases,”Phys. Rev. X9(Apr, 2019) 021012. https://link.aps.org/doi/10.1103/PhysRevX.9.021012

  13. [20]

    Two-dimensional supersolid formation in dipolar condensates,

    T. Bland, E. Poli, C. Politi, L. Klaus, M. A. Norcia, F. Ferlaino, L. Santos, and R. N. Bisset, “Two-dimensional supersolid formation in dipolar condensates,”Phys. Rev. Lett.128(May,

  14. [21]

    Birth, life, and death of a dipolar supersolid,

    M. Sohmen, C. Politi, L. Klaus, L. Chomaz, M. J. Mark, M. A. Norcia, and F. Ferlaino, “Birth, life, and death of a dipolar supersolid,”Phys. Rev. Lett.126(Jun, 2021) 233401. https://link.aps.org/doi/10.1103/PhysRevLett.126.233401

  15. [22]

    Supersolid symmetry breaking from compressional oscillations in a dipolar quantum gas,

    L. Tanzi, S. M. Roccuzzo, E. Lucioni, F. Fam` a, A. Fioretti, C. Gabbanini, G. Modugno, A. Recati, and S. Stringari, “Supersolid symmetry breaking from compressional oscillations in a dipolar quantum gas,”Nature574no. 7778, (Oct, 2019) 382–385. https://doi.org/10.1038/s41586-0...

  16. [23]

    A new form of liquid matter: Quantum droplets,

    Z.-H. Luo, W. Pang, B. Liu, Y.-Y. Li, and B. A. Malomed, “A new form of liquid matter: Quantum droplets,”Frontiers of Physics16no. 3, (Dec, 2020) 32201. https://doi.org/10.1007/s11467-020-1020-2

  17. [24]

    A new state of matter of quantum droplets,

    M. Guo and T. Pfau, “A new state of matter of quantum droplets,”Frontiers of Physics16 no. 3, (Dec, 2020) 32202.https://doi.org/10.1007/s11467-020-1035-8

  18. [25]

    New states of matter with fine-tuned interactions: quantum droplets and dipolar supersolids,

    F. B¨ ottcher, J.-N. Schmidt, J. Hertkorn, K. S. H. Ng, S. D. Graham, M. Guo, T. Langen, and T. Pfau, “New states of matter with fine-tuned interactions: quantum droplets and dipolar supersolids,”Reports on Progress in Physics84no. 1, (Dec, 2020) 012403. https://dx.doi.org/10....

  19. [26]

    Eigenvalues and eigenfunctions of a bose system of hard spheres and its low-temperature properties,

    T. D. Lee, K. Huang, and C. N. Yang, “Eigenvalues and eigenfunctions of a bose system of hard spheres and its low-temperature properties,”Phys. Rev.106(Jun, 1957) 1135–1145. https://link.aps.org/doi/10.1103/PhysRev.106.1135

  20. [27]

    Quantum mechanical stabilization of a collapsing bose-bose mixture,

    D. S. Petrov, “Quantum mechanical stabilization of a collapsing bose-bose mixture,”Phys. Rev. Lett.115(Oct, 2015) 155302. https://link.aps.org/doi/10.1103/PhysRevLett.115.155302

  21. [28]

    Self-trapped quantum balls in binary bose–einstein condensates,

    S. Gautam and S. K. Adhikari, “Self-trapped quantum balls in binary bose–einstein condensates,”Journal of Physics B: Atomic, Molecular and Optical Physics52no. 5, (Feb,

  22. [29]

    Qcd at finite isospin density,

    D. T. Son and M. A. Stephanov, “Qcd at finite isospin density,”Phys. Rev. Lett.86(Jan,

  23. [30]

    Qcd at finite isospin chemical potential,

    Brandt, Bastian B., Endr˝ odi, Gergely, and Schmalzbauer, Sebastian, “Qcd at finite isospin chemical potential,”EPJ Web Conf.175(2018) 07020. https://doi.org/10.1051/epjconf/201817507020

  24. [33]

    Volume of vortex moduli spaces,

    N. S. Manton and S. M. Nasir, “Volume of vortex moduli spaces,”Communications in Mathematical Physics199no. 3, (Jan, 1999) 591–604. https://doi.org/10.1007/s002200050513

  25. [34]

    The Moduli space metric for well separated BPS monopoles,

    G. W. Gibbons and N. S. Manton, “The Moduli space metric for well separated BPS monopoles,”Phys. Lett. B356(1995) 32–38,arXiv:hep-th/9506052

  26. [35]

    E. J. Weinberg,Classical Solutions in Quantum Field Theory: Solitons and Instantons in High Energy Physics. Cambridge Monographs on Mathematical Physics. Cambridge University Press, 2012

  27. [36]

    Magnetized baryonic layer and a novel bps bound in the gauged-non-linear-sigma-model-maxwell theory in (3+1)-dimensions through hamilton-jacobi equation,

    F. Canfora, “Magnetized baryonic layer and a novel bps bound in the gauged-non-linear-sigma-model-maxwell theory in (3+1)-dimensions through hamilton-jacobi equation,”Journal of High Energy Physics2023no. 11, (Nov, 2023) 7. https://doi.org/10.1007/JHEP11(2023)007

  28. [37]

    Superconducting multi-vortices and a novel bps bound in chiral perturbation theory,

    F. Canfora, M. Lagos, and A. Vera, “Superconducting multi-vortices and a novel bps bound in chiral perturbation theory,”Journal of High Energy Physics2024no. 10, (Oct, 2024) 224. https://doi.org/10.1007/JHEP10(2024)224

  29. [38]

    Turbulence in the two-dimensional fourier-truncated gross–pitaevskii equation,

    V. Shukla, M. Brachet, and R. Pandit, “Turbulence in the two-dimensional fourier-truncated gross–pitaevskii equation,”New Journal of Physics15no. 11, (Nov., 2013) 113025. http://dx.doi.org/10.1088/1367-2630/15/11/113025

  30. [40]

    Hitchin, G

    N. Hitchin, G. Segal, N. Woodhouse, and R. Ward,Integrable Systems: Twistors, Loop Groups, and Riemann Surfaces. Oxford Graduate Texts in Mathematics. Clarendon Press, 1999.https://books.google.cl/books?id=B8gNPwEssmgC

  31. [41]

    Babelon, D

    O. Babelon, D. Bernard, and M. Talon,Introduction to Classical Integrable Systems. Cambridge Monographs on Mathematical Physics. Cambridge University Press, 2003

  32. [42]

    Jurdjevic,Optimal Control and Geometry: Integrable Systems

    V. Jurdjevic,Optimal Control and Geometry: Integrable Systems. Cambridge Studies in Advanced Mathematics. Cambridge University Press, 2016

  33. [43]

    Wilczek,Fractional Statistics and Anyon Superconductivity

    F. Wilczek,Fractional Statistics and Anyon Superconductivity. World Scientific, 1990. https://www.worldscientific.com/doi/abs/10.1142/0961

  34. [44]

    Ezawa,Quantum Hall Effects: Recent Theoretical And Experimental Developments (3rd Edition)

    Z. Ezawa,Quantum Hall Effects: Recent Theoretical And Experimental Developments (3rd Edition). World Scientific Publishing Company, 2013. https://books.google.cl/books?id=6io8DQAAQBAJ

  35. [45]

    Effective-field-theory model for the fractional quantum hall effect,

    S. C. Zhang, T. H. Hansson, and S. Kivelson, “Effective-field-theory model for the fractional quantum hall effect,”Phys. Rev. Lett.62(Jan, 1989) 82–85. https://link.aps.org/doi/10.1103/PhysRevLett.62.82

  36. [46]

    Vortex Motion Quantifies Strong Dissipation in a Holographic Superfluid,

    P. Wittmer, C.-M. Schmied, T. Gasenzer, and C. Ewerz, “Vortex Motion Quantifies Strong Dissipation in a Holographic Superfluid,”Phys. Rev. Lett.127no. 10, (2021) 101601, arXiv:2011.12968 [hep-th]. 20

  37. [47]

    Energy-dependent scattering and the Gross-Pitaevskii equation in two-dimensional Bose-Einstein condensates,

    M. D. Lee, S. A. Morgan, M. J. Davis, and K. Burnett, “Energy-dependent scattering and the Gross-Pitaevskii equation in two-dimensional Bose-Einstein condensates,”Phys. Rev. A 65(Apr, 2002) 043617.https://link.aps.org/doi/10.1103/PhysRevA.65.043617

  38. [48]

    Vortices with fractional flux in two-gap superconductors and in extended faddeev model,

    E. Babaev, “Vortices with fractional flux in two-gap superconductors and in extended faddeev model,”Phys. Rev. Lett.89(Jul, 2002) 067001. https://link.aps.org/doi/10.1103/PhysRevLett.89.067001

  39. [49]

    Ground states of one and two fractional vortices in long josephson 0−κjunctions,

    E. Goldobin, D. Koelle, and R. Kleiner, “Ground states of one and two fractional vortices in long josephson 0−κjunctions,”Phys. Rev. B70(Nov, 2004) 174519. https://link.aps.org/doi/10.1103/PhysRevB.70.174519

  40. [50]

    Superconducting vortices carrying a temperature-dependent fraction of the flux quantum,

    Y. Iguchi, R. A. Shi, K. Kihou, C.-H. Lee, M. Barkman, A. L. Benfenati, V. Grinenko, E. Babaev, and K. A. Moler, “Superconducting vortices carrying a temperature-dependent fraction of the flux quantum,”Science380no. 6651, (2023) 1244–1247, https://www.science.org/doi/pdf/10.11...

  41. [51]

    Quantum liquid crystals in an imbalanced fermi gas: Fluctuations and fractional vortices in larkin-ovchinnikov states,

    L. Radzihovsky and A. Vishwanath, “Quantum liquid crystals in an imbalanced fermi gas: Fluctuations and fractional vortices in larkin-ovchinnikov states,”Phys. Rev. Lett.103(Jul,

  42. [52]

    Quantum Fluctuations of Instantons in the Nonlinear Sigma Model,

    V. A. Fateev, I. V. Frolov, and A. S. Shvarts, “Quantum Fluctuations of Instantons in the Nonlinear Sigma Model,”Nucl. Phys. B154(1979) 1–20

  43. [53]

    Some twisted self-dual solutions for the yang-mills equations on a hypertorus,

    G. Hooft, “Some twisted self-dual solutions for the yang-mills equations on a hypertorus,” Communications in Mathematical Physics81no. 2, (Jun, 1981) 267–275. https://doi.org/10.1007/BF01208900

  44. [54]

    Three-dimensional gauge configurations and their properties in qcd,

    J. M. Cornwall and G. Tiktopoulos, “Three-dimensional gauge configurations and their properties in qcd,”Physics Letters B181no. 3, (1986) 353–358. https://www.sciencedirect.com/science/article/pii/0370269386900626

  45. [55]

    Fractional topological charge insu(n) gauge theories without dynamical quarks,

    V. P. Nair and R. D. Pisarski, “Fractional topological charge insu(n) gauge theories without dynamical quarks,”Phys. Rev. D108(Oct, 2023) 074007. https://link.aps.org/doi/10.1103/PhysRevD.108.074007

  46. [56]

    Review on fractional vortex beam,

    H. Zhang, J. Zeng, X. Lu, Z. Wang, C. Zhao, and Y. Cai, “Review on fractional vortex beam,”Nanophotonics11no. 2, (2022) 241–273. https://doi.org/10.1515/nanoph-2021-0616

  47. [57]

    Kleinert,Gauge fields in condensed matter

    H. Kleinert,Gauge fields in condensed matter. Vol. 2: Stresses and defects. Differential geometry, crystal melting. 1989

  48. [58]

    Quantum field theory in curved graphene spacetimes, Lobachevsky geometry, Weyl symmetry, Hawking effect, and all that,

    A. Iorio and G. Lambiase, “Quantum field theory in curved graphene spacetimes, Lobachevsky geometry, Weyl symmetry, Hawking effect, and all that,”Phys. Rev.D90 no. 2, (2014) 025006,arXiv:1308.0265 [hep-th]

  49. [59]

    Curved Spacetimes and Curved Graphene: a status report of the Weyl-symmetry approach,

    A. Iorio, “Curved Spacetimes and Curved Graphene: a status report of the Weyl-symmetry approach,”Int. J. Mod. Phys.D24no. 05, (2015) 1530013,arXiv:1412.4554 [hep-th]

  50. [60]

    (anti-)de sitter, poincar´ e, super symmetries, and the two dirac points of graphene,

    A. Iorio and P. Pais, “(anti-)de sitter, poincar´ e, super symmetries, and the two dirac points of graphene,”Annals of Physics398(2018) 265 – 286. http://www.sciencedirect.com/science/article/pii/S0003491618302495

  51. [61]

    Comparison of splitting methods for deterministic/stochastic gross–pitaevskii equation,

    J. Geiser and A. Nasari, “Comparison of splitting methods for deterministic/stochastic gross–pitaevskii equation,”Mathematical and Computational Applications24no. 3, (2019) . https://www.mdpi.com/2297-8747/24/3/76. 21

  52. [2001]

    592–595.https://link.aps.org/doi/10.1103/PhysRevLett.86.592

  53. [2009]

    010404.https://link.aps.org/doi/10.1103/PhysRevLett.103.010404

  54. [2019]

    055302.https://dx.doi.org/10.1088/1361-6455/aafb92. 19

  55. [2022]

    195302.https://link.aps.org/doi/10.1103/PhysRevLett.128.195302

Pith tools

Reviewed August 10, 2026 · model on record in the stance chip above.