We study the existence and multiplicity of positive solutions for a class of nonlocal elliptic equations involving the bosonic operator $ -\Delta e^{-c\Delta} $, which arises in models from bosonic string theory and nonlocal cosmology.
For the parametric problem with a nonlinearity that is sublinear at infinity,
$ -\Delta e^{-c\Delta}u + u = \lambda a(x)g(u) \quad \text{in } \mathbb{R}^N, $
we use tools tailored to the nonlocal framework, including sharp decay estimates for the associated kernel, a strong maximum principle, and the method of lower and upper solutions.
Our main result identifies a critical parameter $ \lambda^*>0 $ such that the problem admits no positive solutions for $ \lambda<\lambda^* $, at least one solution for $ \lambda = \lambda^* $, and at least two ordered positive solutions for $ \lambda>\lambda^* $. One solution follows from coercivity arguments together with the method of lower and upper solutions, whereas the second is obtained through a nontrivial linking argument. This multiplicity pattern reveals that the problem exhibits a structure that can be viewed as a dual counterpart to the classical concave-convex type equations. A key ingredient in this analysis is a local minimizer equivalence principle between the natural energy space and a suitable weighted space with nonempty interior, which enables comparison and minimization techniques in the whole space.
| Citation: |
| [1] |
C. O. Alves, T. Boudjeriou and H. Prado, Existence of solution and qualitative behavior for a class of heat equations, J. Differ. Equ., 400 (2024), 457-486.
doi: 10.1016/j.jde.2024.04.019.
|
| [2] |
C. O. Alves, H. Prado and E. G. Reyes, Existence of smooth solutions for a class of Euclidean bosonic equations, J. Differ. Equ., 323 (2022), 229-252.
doi: 10.1016/j.jde.2022.03.031.
|
| [3] |
J. Arratia and P. Ubilla, An Ambrosetti–Prodi problem involving the bosonic operator, submitted.
|
| [4] |
H. Brézis and L. Nirenberg, $H^1$ versus $C^1$ local minimizers, C. R. Acad. Sci. Paris, 317 (1993), 465-472.
|
| [5] |
G. Calcagni, M. Montobbio and G. Nardelli, Localization of nonlocal theories, Phys. Lett. B, 662 (2008), 285-289.
doi: 10.1016/j.physletb.2008.03.024.
|
| [6] |
S. Carl, D. G. Costa and H. Tehrani, $\mathcal{D}^{1, 2}(\mathbb{R}^N)$ versus $C(\mathbb{R}^N)$ local minimizers and a Hopf-type maximum principle, J. Differ. Equ., 261 (2016), 2006-2025.
doi: 10.1016/j.jde.2016.04.019.
|
| [7] |
F. J. S. A. Corrêa, A. B. Nóbrega and L. S. Tavares, Solutions for an Euclidean bosonic equation via variational and bifurcation methods, J. Differ. Equ., 363 (2023), 491-517.
doi: 10.1016/j.jde.2023.03.033.
|
| [8] |
Y. Du, A deformation lemma and some critical point theorems, Bull. Aust. Math. Soc., 43 (1991), 161-168.
doi: 10.1017/S0004972700028896.
|
| [9] |
P. Górka, H. Prado and E. G. Reyes, Generalized Euclidean bosonic string equations, Oper. Theory Adv. Appl., 224 (2012), 147-169.
doi: 10.1007/978-3-0348-0414-1_8.
|
| [10] |
C. Long, J. Tan and A. Xia, Asymptotically linear Euclidean bosonic equations, Acta Appl. Math., 193 (2024), 13, 12 pp.
doi: 10.1007/s10440-024-00693-8.
|
| [11] |
D. Montreanu and C. Varga, Some critical point results for locally Lipschitz functionals, Commun. Appl. Nonlinear Anal., 4 (1997), 17-33.
|
| [12] |
H. Prado and E. G. Reyes, Nonlinear evolution equations with infinitely many derivatives, Complex Anal. Oper. Theory, 10 (2016), 1577-1590.
doi: 10.1007/s11785-016-0534-7.
|
| [13] |
E. M. Stein and G. Weiss, Introduction to Fourier Analysis on Euclidean Spaces, Princeton Univ. Press, Princeton, 1971.
|
| [14] |
C. A. Stuart, An introduction to elliptic equations on $\mathbb{R}^N$, in: Nonlinear Functional Analysis and Applications to Differential Equations (Trieste, 1997), World Sci. Publ., River Edge, NJ, 1998,237-285.
|
| [15] |
G. N. Watson, A Treatise on the Theory of Bessel Functions, Cambridge Univ. Press, Cambridge, 1922; 2nd ed. 1944.
|
| [16] |
H. Wendland, Scattered Data Approximation, Cambridge Monogr. Appl. Comput. Math., Cambridge Univ. Press, Cambridge, 2004.
|
| [17] |
M. Yang, J. Abrantes, P. Ubilla and J. Zhou, Global multiplicity of positive solutions for a sublinear elliptic equation in $\mathbb{R}^N$, J. Differ. Equ., 416 (2025), 159-189.
doi: 10.1016/j.jde.2024.09.052.
|