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REVIEW 4 major objections 6 minor 37 references

Structure of a single-quantum vortex in $^3$He-A

T0 review · 4 major / 6 minor · reviewed 2026-08-11 · deepseek-v4-flash

Pith's one-line read The internal structure of a single-quantum vortex in superfluid 3He-A has been calculated for the first time at both core scales, giving a 55.4° disgyration tilt, offset hard and soft cores, and a polar core that carries 18.2% of the…

desk verdict First simultaneous resolution of hard and soft cores of the 3He-A single-quantum vortex, with a clean analytic cross-check; needs a convergence study before the headline numbers are taken as precise. read the letter →

arxiv 2412.13764 v1 pith:KYHCG3JR submitted 2024-12-18 cond-mat.other

classification cond-mat.other
keywords Superfluid3He-AQuantizedvorticesGinzburg-LandaueccentricfractionalskyrmionradialdisgyrationpolarcoremasscurrentMermin-Horelation
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

This paper reports the first numerical calculation of the internal structure of a single-quantum vortex in the A phase of superfluid helium-3 that resolves both the tiny hard core (coherence length, about ten nanometres) and the much larger soft core (dipole length, about ten micrometres) in a single simulation. The calculation pins down the l-vector texture around the vortex, giving a tilt angle of roughly 55.4 degrees for the radial disgyration, and shows the hard and soft cores are offset from the vortex centre by -22.67ξ and +44.50ξ respectively. It also reveals that the superfluid mass current is highly asymmetric and flows mostly through the polar-phase hard core, and an analytic model reproduces this current without any fitting parameters. The polar core is found to carry about 18.2 percent of the total vortex energy, much larger than the few percent estimated earlier.

What carries the argument

The load-bearing object is the tilted radial disgyration, Eq. (21): $\hat{l} = s[\hat{y}\sin\phi + \cos\phi(\hat{x}\cos\eta + \hat{z}\nu\sin\eta)]$, with a constant tilt angle $\eta$, surrounding a polar-phase hard core where the $\hat{n}$ component vanishes. The Mermin-Ho relation $\nabla\times\mathbf{v}_s = (\hbar/4m_3)\sum_{ijk}\epsilon_{ijk}\hat{l}_i(\nabla\hat{l}_j\times\nabla\hat{l}_k)$ ties circulation to the skyrmion number $N = \frac{1}{4\pi}\int \hat{l}\cdot(\partial_x\hat{l}\times\partial_y\hat{l})\,dx\,dy$ through $\nu = 2N$; for the single-quantum vortex $N = 1/2$, which requires the hard core and disgyration. The analytic current model, Eqs. (26)-(27), derived from this texture plus the core suppression function $f(r)$, reproduces the numerical superflow without fitting parameters and shows the polar core acts as a channel for the mass current.

What would settle it

A nuclear magnetic resonance measurement of a single-quantum vortex in 3He-A: if the measured satellite spectrum does not match the spectrum computed from the predicted l-vector texture (η ≈ 55.4°, hard and soft cores separated by about 67ξ), the quantitative structure presented here is refuted.

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Extended reading notes

Core claim

The single-quantum vortex in $^3$He-A is an eccentric fractional skyrmion: the orbital angular momentum unit vector $\hat{l}$ rotates over half the unit sphere, forcing a hard core in the polar phase and a tilted radial disgyration around it, together with a hyperbolic soft core on the opposite side. Minimizing the Ginzburg-Landau free energy on a tetrahedral mesh that resolves both the coherence-length hard core and the dipolar-length soft core yields quantitative values: the disgyration is tilted out of the $xy$-plane by $\eta \approx 55.4^\circ$, the hard core sits at $x = -22.67\xi$, the soft core at $x = 44.50\xi$, and the polar core contributes $18.2\%$ of the total vortex energy when the circulating flow outside the simulation box is included. The paper's new result is the mass current: $j_y(x,y) = -(4m_3 K \Delta_A^2/\hbar)\sin\eta\,\sin^2\phi/r$ away from the core and $j_y(x,0) = -(4m_3 K \Delta_A^2/\hbar)\sin\eta\, f'(|x|)$ on the axis through the core, where $f(r)$ is the suppression of the $\hat{n}$ amplitude inside the hard core. This analytic form reproduces the numerical flow without fitting parameters, establishing that the asymmetric channeling of superflow through the polar core is a direct consequence of the tilted $\hat{l}$-texture, analogous to a magnetization current.

Load-bearing premise

All quantitative numbers rest on the Ginzburg-Landau free energy functional with coefficients from reference [31] being accurate at p = 30 bar and T = 0.9Tc, a temperature not very close to Tc, and the paper reports no sensitivity, convergence, or mesh-resolution tests to support the quoted precision.

Editorial extensions

If this is right

  • The quantitative texture allows computing experimental signatures such as the NMR response of the single-quantum vortex, enabling direct comparison with existing and future observations.
  • The phase diagram of vortices in $^3$He-A can now be completed theoretically, because the SQV energy and structure are known quantitatively.
  • The strong flow through the polar core provides a concrete setting for studying core-bound fermion states and Weyl quasiparticles in a controlled laboratory system.
  • The eccentric fractional skyrmion structure confirms the analogy with spinor Bose-Einstein condensate vortices, where such structures have been predicted and observed.
  • The 18.2% polar-core energy share, much larger than earlier few-percent estimates, may change the relative stability of single- and double-quantum vortices under different conditions.

Reading between the lines

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

  • If the analytic current model is exact in the Ginzburg-Landau limit, the total current through the polar core depends only on the tilt angle $\eta$ and not on the shape of the core suppression function; this could be tested in spinor Bose-Einstein condensates, where analogous eccentric fractional skyrmion structures can be imaged directly.
  • The 18.2% polar-core energy share, if correct at 30 bar and 0.9Tc, suggests that at other pressures or temperatures the single-quantum vortex may change stability relative to the double-quantum vortex; a phase-diagram scan across the p-T plane would reveal such a transition.
  • The asymmetric current channeling implies a transverse force on the vortex line (a Hall-like response) that should enter the equations of vortex motion; if measured, it would provide an independent check of the model beyond NMR.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

4 major / 6 minor

Summary. The manuscript reports a finite-element Ginzburg-Landau minimization of a single-quantum vortex (SQV) in superfluid 3He-A at p=30 bar and T=0.9Tc, with boundary conditions l=d=x and a magnetic field along z. The mesh resolves the hard core with spacing xi/3 out to r=100xi and extends to Rcalc=1000xi with periodic boundary conditions in z. The resulting texture has a tilted radial disgyration with eta~55.4 deg, a hard core shifted to x=-22.67xi, a hyperbolic soft core at x=44.50xi, and a strongly asymmetric superfluid mass current that is largest in the polar hard core. An analytic current model based on an ansatz with constant tilt eta and order-parameter suppression f(r) reproduces the numerical current. The polar core is estimated to contribute ~18.2% of the vortex energy for an outer cutoff at the intervortex distance corresponding to Omega=1 rad/s. The four (nu,s) vortex variants are found to be degenerate within 0.04%. The authors conclude that this is the first quantitative determination of the SQV structure and note connections to eccentric fractional skyrmions in spinor BECs.

Significance. If the quantitative claims survive the numerical verification requested below, this is a genuinely useful contribution: it is, to my knowledge, the first GL calculation that resolves both the coherence-length hard core and the dipole-length soft core of the SQV in the same simulation. The paper is self-contained methodologically: it gives the tetrahedral discretization, analytic integrals for bulk and gradient terms, the functional gradients, and the GPU L-BFGS minimization, which would allow reproduction. The analytic current model of Sec. 4 is a valuable physical explanation of the asymmetric flow and channeling through the polar core. The connection to eccentric fractional skyrmions in spinor BECs gives the work broader relevance. The predicted texture and current profile are, in principle, falsifiable via NMR signatures and transverse-current experiments, which adds value. The main limitations are an absence of numerical convergence studies and of error estimates for the headline numbers; these are fixable but currently prevent the paper from supporting 'quantitative determination' as strongly as claimed.

major comments (4)
  1. [Section 2 and Section 4] The central quantitative claims are reported for a single mesh with near-core spacing xi/3 and Rcalc=1000xi, and no mesh-convergence or domain-size study is presented. With b~67xi~0.25xi_d, the dipole length is xi_d~268xi, so Rcalc~3.7xi_d and the soft-core texture cannot be assumed free of finite-size effects. The values eta~55.4 deg, x=-22.67xi, x=44.50xi, and the 18.2% energy fraction are quoted to 2-3 significant figures without error bars. Please add systematic studies varying the near-core spacing (e.g. xi/6 and xi/9) and the outer radius (e.g. 1500xi and 2000xi), and report the resulting changes in these observables; a minimization stopping criterion should also be stated.
  2. [Section 4 (polar-core energy)] The 18.2% polar-core energy contribution depends on two choices that are not given sensitivity tests: the definition of the hard core as the region where the order-parameter amplitude deviates by more than 5% from bulk, and the outer cutoff rv in Eq. (19) evaluated at Omega=1 rad/s. Since previous estimates are 'a few percent,' the discrepancy makes the new value physically interesting only if its dependence on these choices is shown. Please report the energy fraction for thresholds (e.g. 3%, 7%, 10%) and for at least one other realistic rotation rate or cutoff.
  3. [Section 4, Eqs. (26)-(27)] The statement that the model current matches 'without fitting parameters' should be qualified. The model uses eta=55.39 deg and the hard-core position x=-22.67xi taken directly from the minimized texture, so the agreement is an internal consistency check of the ansatz rather than an independent validation of those two numbers. The paper should state this explicitly and, if possible, show the model current for eta varied within the numerical uncertainty to indicate the precision of the match.
  4. [Section 4, GL input (Ref. [31])] The quantitative outputs inherit the accuracy of the GL functional and its coefficients at p=30 bar and T=0.9Tc, a temperature not very close to Tc. No discussion of the expected systematic error of the GL approximation, nor of sensitivity to the beta coefficients or the magnetic-field term, is given. This is not a reason to doubt the qualitative structure, but it limits the precision that can be claimed for eta and the core positions; please add an explicit statement of expected GL-level uncertainty and, if feasible, a calculation at one additional temperature.
minor comments (6)
  1. [Eq. (17)] The typeset expression 'A. µm' in the last term appears to be a subscript artifact; the index structure of this K3 term should be corrected or clarified.
  2. [Eqs. (3), (18), (19), (21)] The symbol nu is used both for the circulation quantum number and for the +/-1 vortex/antivortex sign in Eq. (21); using a different symbol, such as sigma, would avoid confusion.
  3. [Fig. 5 and Sec. 4] The caption of Fig. 5 gives eta=55.39 deg, while the text and Fig. 1 give eta~55.4 deg; the precision of the value should be made consistent, and an error estimate should be attached if the value is meant literally.
  4. [Section 4] The statement that external rotation is neglected 'as it is not expected to have an effect on the length scales of a single vortex' needs a brief justification, since the energy fraction computed in the same section explicitly uses an outer cutoff from rotation.
  5. [Section 4] The four degenerate vortex variants are reported to be equivalent within 0.04%, but no absolute energy per unit length is given; providing the vortex energy in units such as Delta_A^2 xi^2 would allow quantitative comparison with future calculations.
  6. [General] A data or code availability statement for the minimized order-parameter textures would aid reproducibility and is recommended.

Circularity Check

1 steps flagged · score 2.0 of 10

Simulation is self-contained; the analytic current model is a consistency check that reuses simulation-derived η and core position, not an independent prediction.

  1. fitted input called prediction [Section 4, Eqs. (23)–(27) and Fig. 5 caption]
    "The solid lines are values from the numerical calculation, and dashed lines represent the model in Eq. (26), evaluated without fitting parameters with the tilt η = 55.39◦ and with the location of the hard core x = −22.67ξ as in the structure in Fig. 1."

    The 'model' is not an independent prediction of the vortex structure: its tilt angle η = 55.39° and core position x = −22.67ξ are read off from the very same GL minimization that produces the numerical current curves shown as solid lines. Moreover, Eq. (27) evaluates j_y(x,0) using the suppression factor f(r) from the numerical order-parameter solution, so the on-axis current is essentially the derivative of the computed amplitude. The excellent agreement is therefore a self-consistency check of the ansatz/current formula, not an external validation of the quoted structural parameters. The paper is transparent about using these inputs, so this is mild circularity rather than a fabricated prediction.

full rationale

The central calculation is a direct numerical minimization of the Ginzburg-Landau free energy with specified mesh, boundary conditions, and initial winding; the resulting texture, core locations, tilt angle, and energy contributions are outputs of that minimization and are not identical to the inputs by construction. The only close-to-circular validation is the analytic current model in Section 4: it takes η and the hard-core location from the same minimized texture, and Eq. (27) uses the numerical suppression factor f(r), so the claimed 'excellent match without fitting parameters' is best described as a self-consistency check. The paper states these parameters explicitly, and the main structural claims do not depend on the analytic model being an independent prediction. The GL coefficients are cited to the authors' prior work [31], but they are a standard parameter set external to this vortex calculation and are not fitted to the SQV data, so that self-citation is not circular. The absence of a mesh-convergence or domain-size study is a numerical robustness concern and a limitation on the quoted precision, but it is not a circularity of the derivation chain.

Assumptions & free parameters 2 free parameters · 5 assumptions · 0 invented entities

The central numerical results rest on the GL functional taken from prior work by the same group, on straight-vortex and large-domain assumptions, and on convergence of L-BFGS; none of these are independently verified in the paper. The analytic current model imports the numerically obtained tilt angle and core position, so it is a consistency check.

free parameters (2)
  • Hard-core boundary threshold = 5% amplitude deviation from bulk
    Defines the hard-core region and its energy contribution; the quoted 18.2% energy share changes if this threshold is varied.
  • Inter-vortex distance cutoff = r_v about 0.01 cm (Omega=1 rad/s)
    Used to estimate the flow energy outside the simulation domain via Eq. (19); the polar-core energy fraction depends on this arbitrarily chosen cutoff.
assumptions (5)
  • domain assumption The Ginzburg-Landau free energy with coefficients from Ref [31] accurately describes the vortex structure in 3He-A at p=30 bar and T=0.9Tc.
    All quantitative outputs depend on this functional; no sensitivity check is provided, and GL accuracy at T=0.9Tc is not established.
  • domain assumption The vortex is straight and uniform along the z axis, represented by two periodic layers with spacing xi.
    Used to reduce a 3D vortex to a 2D problem; justified for an infinitely long straight vortex.
  • domain assumption The boundary condition at R_calc=1000xi with bulk A-phase order parameter and 2π phase winding represents an isolated SQV with negligible finite-size effects.
    The soft core extends to about 0.25 xi_d; the domain radius of 1000xi should be sufficient but is not tested against larger domains.
  • domain assumption L-BFGS minimization converges to the lowest-energy vortex state; the four symmetry classes are the only relevant local minima.
    The paper states the four types have equal energy within 0.04%, but no convergence criterion or global-minimum search is reported.
  • ad hoc to paper The order parameter near the hard core takes the ansatz (23)-(24) with constant tilt angle eta, enabling the analytic current model.
    This assumption is introduced solely to derive Eqs. (26)-(27); the match to numerics is a consistency check, not an independent validation.

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Pith. "Pith review of Structure of a single-quantum vortex in $^3$He-A." pith.science (2026). https://pith.science/paper/KYHCG3JR

@misc{pith2026241213764,
  author       = {Pith},
  title        = {Pith review of: Structure of a single-quantum vortex in $^3$He-A},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/KYHCG3JR}},
  note         = {Machine review of arXiv:2412.13764}
}
abstract

We have performed numerical calculations of the structure of the single-quantum vortex in superfluid $^3$He-A. The GPU-accelerated large-scale numerical simulation is performed in the Ginzburg-Landau model and resolves length scales of both coherence-length-sized hard core and dipolar-length-sized soft core of the vortex. The calculations support previously suggested qualitative structure of the vortex, recently named as eccentric fractional skyrmion, and provide numerical values for the vortex energy, sizes and locations of the hard and soft cores and highly-asymmetric flow profile of the vortex.

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Works this paper leans on

37 extracted references · 32 canonical work pages

  1. [1]

    Mermin, N.D., Ho, T.-L.: Circulation and angular momentum in the A phase of superfluid helium-3. Phys. Rev. Lett. 36, 594–597 (1976) https://doi.org/10. 1103/PhysRevLett.36.594

  2. [2]

    Ambegaokar, V., deGennes, P.G., Rainer, D.: Landau-Ginsburg equations for an anisotropic superfluid. Phys. Rev. A 9, 2676–2685 (1974) https://doi.org/10. 1103/PhysRevA.9.2676

  3. [3]

    Physics Letters A 44(4), 271–272 (1973) https://doi.org/10.1016/0375-9601(73)90916-X

    De Gennes, P.G.: Long range distortions in an anisotropic superfluid. Physics Letters A 44(4), 271–272 (1973) https://doi.org/10.1016/0375-9601(73)90916-X

  4. [4]

    JETP Lett

    Volovik, G.E., Kopnin, N.B.: Rotating 3He − A. JETP Lett. 25, 22 (1977)

  5. [5]

    Jour- nal of Low Temperature Physics 42, 503–514 (1981) https://doi.org/10.1007/ BF00117428

    Volovik, G.E., Hakonen, P.J.: Vortices in 3He-A in a weak magnetic field. Jour- nal of Low Temperature Physics 42, 503–514 (1981) https://doi.org/10.1007/ BF00117428

  6. [6]

    Maki, K.: Analytic vortices and magnetic resonances in rotating superfluid 3He − A. Phys. Rev. B 27, 4173–4180 (1983) https://doi.org/10.1103/PhysRevB.27. 14 4173

  7. [7]

    Maki, K.: Analytic vortices and magnetic resonances in rotating superfluid 3He − A ii. Phys. Rev. B 28, 2452–2454 (1983) https://doi.org/10.1103/PhysRevB.28. 2452

  8. [8]

    Journal of Low Temperature Physics51, 279–290 (1983) https://doi.org/10.1007/BF00683557

    Sepp¨ al¨ a, H.K., Volovik, G.E.: Evidence for nonsingular vorticity in the Helsinki experiments on rotating 3He-A. Journal of Low Temperature Physics51, 279–290 (1983) https://doi.org/10.1007/BF00683557

Show all 37 references
  1. [9]

    Fetter, A.L., Sauls, J.A., Stein, D.L.: Vortices in rotating superfluid 3He-A. Phys. Rev. B 28, 5061–5074 (1983) https://doi.org/10.1103/PhysRevB.28.5061

  2. [10]

    Sepp¨ al¨ a, H.K., Hakonen, P.J., Krusius, M., Ohmi, T., Salomaa, M.M., Simola, J.T., Volovik, G.E.: Continuous vortices with broken symmetry in rotating super- fluid 3He-A. Phys. Rev. Lett. 52, 1802–1805 (1984) https://doi.org/10.1103/ PhysRevLett.52.1802

  3. [11]

    Vulovic, V.Z., Stein, D.L., Fetter, A.L.: NMR of textures in rotating 3He − A. Phys. Rev. B 29, 6090–6095 (1984) https://doi.org/10.1103/PhysRevB.29.6090

  4. [12]

    Zotos, X., Maki, K.: Analytic vortices and magnetic resonances in rotating super- fluid 3He-A. III. Phys. Rev. B 30, 145–151 (1984) https://doi.org/10.1103/ PhysRevB.30.145

  5. [13]

    Hakonen, P.J., Ikkala, O.T., Islander, S.T.: Experiments on vortices in rotating superfluid 3He-A. Phys. Rev. Lett.49, 1258–1261 (1982) https://doi.org/10.1103/ PhysRevLett.49.1258

  6. [14]

    Journal of Low Temperature Physics 53, 425–476 (1983) https://doi.org/10.1007/BF00682488

    Hakonen, P.J., Ikkala, O.T., Islander, S.T.: NMR experiments on rotating super- fluid 3He-A and 3He-B and their theoretical interpretation. Journal of Low Temperature Physics 53, 425–476 (1983) https://doi.org/10.1007/BF00682488

  7. [15]

    Journal of Low Temperature Physics 67, 145–153 (1987) https://doi.org/10.1007/BF00681825

    Fetter, A.L.: Vortex structures in rotating 3He-A. Journal of Low Temperature Physics 67, 145–153 (1987) https://doi.org/10.1007/BF00681825

  8. [16]

    Salomaa, M.M., Volovik, G.E.: Quantized vortices in superfluid 3He. Rev. Mod. Phys. 59, 533–613 (1987) https://doi.org/10.1103/RevModPhys.59.533

  9. [17]

    Parts, U., Karim¨ aki, J.M., Koivuniemi, J.H., Krusius, M., Ruutu, V.M.H., Thuneberg, E.V., Volovik, G.E.: Phase diagram of vortices in superfluid3 He −A. Phys. Rev. Lett. 75, 3320–3323 (1995) https://doi.org/10.1103/PhysRevLett.75. 3320

  10. [18]

    Journal of Low Temperature Physics 103, 331–343 (1996) https://doi.org/10.1007/BF00754793 15

    Ruutu, V.M.H., Parts, U., Krusius, M.: NMR signatures of topological objects in rotating superfluid 3He-A. Journal of Low Temperature Physics 103, 331–343 (1996) https://doi.org/10.1007/BF00754793 15

  11. [19]

    Nature 404, 471–473 (2000) https://doi.org/10.1038/35006583

    Blaauwgeers, R., Eltsov, V.B., Krusius, M., Ruohio, J.J., Schanen, R., Volovik, G.E.: Double-quantum vortex in superfluid 3He-A. Nature 404, 471–473 (2000) https://doi.org/10.1038/35006583

  12. [20]

    Czech J Phys 46 (Suppl 1), 13–14 (1996) https://doi.org/10.1007/ BF02569422

    Parts, U., Avilov, V.V., Koivuniemi, J.H., Krusius, M., Ruohio, J.J., Ruutu, V.M.H.: Vortex arrays of coexisting singly and doubly quantized vortex lines in 3He-A. Czech J Phys 46 (Suppl 1), 13–14 (1996) https://doi.org/10.1007/ BF02569422

  13. [21]

    Parts, U., Avilov, V.V., Koivuniemi, J.H., Kopnin, N.B., Krusius, M., Ruohio, J.J., Ruutu, V.M.H.: Coexistence of single and double quantum vortex lines. Phys. Rev. B 62, 5865–5876 (2000) https://doi.org/10.1103/PhysRevB.62.5865

  14. [22]

    Journal of Low Temperature Physics 25, 225–243 (1976) https://doi.org/ 10.1007/BF00654831

    Fishman, F., Privorotskii, I.A.: Theory of the de Gennes disgyration in superfluid 3He. Journal of Low Temperature Physics 25, 225–243 (1976) https://doi.org/ 10.1007/BF00654831

  15. [23]

    Muzikar, P.: The internal structure of a de Gennes disgyration in 3He-A. J. Phys. Colloques 39, 53 (1978) https://doi.org/10.1051/jphyscol:1978625

  16. [24]

    Karim¨ aki, J.M., Thuneberg, E.V.: Periodic vortex structures in superfluid 3He − A. Phys. Rev. B 60, 15290–15301 (1999) https://doi.org/10.1103/PhysRevB.60. 15290

  17. [25]

    Rantanen, R., Eltsov, V.B.: Transition in vortex skyrmion structures in superfluid 3He−A driven by an analog of the zero-charge effect. Phys. Rev. B 107, 104505 (2023) https://doi.org/10.1103/PhysRevB.107.104505

  18. [26]

    Takeuchi, H.: Spin-current instability at a magnetic domain wall in a ferromag- netic superfluid: A generation mechanism of eccentric fractional skyrmions. Phys. Rev. A 105, 013328 (2022) https://doi.org/10.1103/PhysRevA.105.013328

  19. [27]

    https://arxiv.org/abs/2408.11217

    Huh, S., Yun, W., Yun, G., Hwang, S., Kwon, K., Hur, J., Lee, S., Takeuchi, H., Kim, S.K., Choi, J.-y.: Beyond skyrmion spin texture from quantum Kelvin- Helmholtz instability (2024). https://arxiv.org/abs/2408.11217

  20. [28]

    Lovegrove, J., Borgh, M.O., Ruostekoski, J.: Stability and internal structure of vortices in spin-1 Bose-Einstein condensates with conserved magnetization. Phys. Rev. A 93, 033633 (2016) https://doi.org/10.1103/PhysRevA.93.033633

  21. [29]

    Nature 443, 312–315 (2006) https://doi.org/10.1038/nature05094

    Sadler, L.E., Higbie, J.M., Leslie, S.R., Vengalattore, M., Stamper-Kurn, D.M.: Spontenous symmetry breaking in a quenched ferromagnetic spinor Bose-Einstein condensate. Nature 443, 312–315 (2006) https://doi.org/10.1038/nature05094

  22. [30]

    Nat Commun 10, 4772 (2019) https://doi.org/10.1038/ 16 s41467-019-12787-1

    Weiss, L.S., Borgh, M.O., Blinova, A., Ollikainen, T., M¨ ott¨ onen, M., Ruostekoski, J., Hall, D.S.: Controlled creation of a singular spinor vortex by circumvent- ing the dirac belt trick. Nat Commun 10, 4772 (2019) https://doi.org/10.1038/ 16 s41467-019-12787-1

  23. [31]

    Rantanen, R., Eltsov, V.: Competition of vortex core structures in super- fluid 3He−B. Phys. Rev. Res. 6, 043112 (2024) https://doi.org/10.1103/ PhysRevResearch.6.043112

  24. [32]

    Mathematical Programming 45, 503–528 (1989) https://doi.org/ 10.1007/BF01589116

    Liu, D.C., Nocedal, J.: On the limited memory BFGS method for large scale optimization. Mathematical Programming 45, 503–528 (1989) https://doi.org/ 10.1007/BF01589116

  25. [33]

    GitHub (2012)

    Wetzl, J., Taubmann, O.: CudaLBFGS. GitHub (2012). https://github.com/ jwetzl/CudaLBFGS

  26. [34]

    Thuneberg, E.V.: Ginzburg-Landau theory of vortices in superfluid 3He-B. Phys. Rev. B 36, 3583–3597 (1987) https://doi.org/10.1103/PhysRevB.36.3583

  27. [35]

    Journal of Low Temperature Physics 21, 525–534 (1975) https://doi

    Cross, M.C.: A generalized Ginzburg-Landau approach to the superfluidity of helium 3. Journal of Low Temperature Physics 21, 525–534 (1975) https://doi. org/10.1007/BF01141607

  28. [36]

    Nissinen, J., Volovik, G.E.: Dimensional crossover of effective orbital dynamics in polar distorted 3He−A: Transitions to antispacetime. Phys. Rev. D 97, 025018 (2018) https://doi.org/10.1103/PhysRevD.97.025018

  29. [37]

    Boyle, L., Finn, K., Turok, N.: CP T-symmetric universe. Phys. Rev. Lett. 121, 251301 (2018) https://doi.org/10.1103/PhysRevLett.121.251301 17

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