| Title:
             | 
Methods of analysis of the condition for correct solvability in $L_p (\mathbb R)$ of general Sturm-Liouville equations (English) | 
| Author:
             | 
Chernyavskaya, Nina A. | 
| Author:
             | 
Shuster, Leonid A. | 
| Language:
             | 
English | 
| Journal:
             | 
Czechoslovak Mathematical Journal | 
| ISSN:
             | 
0011-4642 (print) | 
| ISSN:
             | 
1572-9141 (online) | 
| Volume:
             | 
64 | 
| Issue:
             | 
4 | 
| Year:
             | 
2014 | 
| Pages:
             | 
1067-1098 | 
| Summary lang:
             | 
English | 
| . | 
| Category:
             | 
math | 
| . | 
| Summary:
             | 
We consider the equation $$\label {1} - (r(x)y'(x))'+q(x)y(x)=f(x),\quad x\in \mathbb R \eqno {(*)} $$ where $f\in L_p(\mathbb R)$, $p\in (1,\infty )$ and \begin {gather} r>0,\quad q\ge 0,\quad \frac {1}{r}\in L_1^{\rm loc}(\mathbb R),\quad q\in L_1^{\rm loc}(\mathbb R), \nonumber \\ \lim _{|d|\to \infty }\int _{x-d}^x \frac {{\rm d} t}{r(t)}\cdot \int _{x-d}^x q(t) {\rm d} t=\infty . \nonumber \end {gather} In an earlier paper, we obtained a criterion for correct solvability of ($*$) in $L_p(\mathbb R),$ $p\in (1,\infty ).$ In this criterion, we use values of some auxiliary implicit functions in the coefficients $r$ and $q$ of equation ($*$). Unfortunately, it is usually impossible to compute values of these functions. In the present paper we obtain sharp by order, two-sided estimates (an estimate of a function $f(x)$ for $x\in (a,b)$ through a function $g(x)$ is sharp by order if $c^{-1}|g(x)|\le |f(x)|\le c|g(x)|,$ $x\in (a,b),$ $c=\rm const$) of auxiliary functions, which guarantee efficient study of the problem of correct solvability of ($*$) in $L_p(\mathbb R),$ $p\in (1,\infty ).$ (English) | 
| Keyword:
             | 
correct solvability | 
| Keyword:
             | 
Sturm-Liouville equation | 
| MSC:
             | 
34B24 | 
| idZBL:
             | 
Zbl 06433715 | 
| idMR:
             | 
MR3304799 | 
| DOI:
             | 
10.1007/s10587-014-0154-1 | 
| . | 
| Date available:
             | 
2015-02-09T17:42:34Z | 
| Last updated:
             | 
2020-07-03 | 
| Stable URL:
             | 
http://hdl.handle.net/10338.dmlcz/144162 | 
| . | 
| Reference:
             | 
[1] Chernyavskaya, N. A., El-Natanov, N., Shuster, L. A.: Weighted estimates for solutions of a Sturm-Liouville equation in the space $L_1(\mathbb R)$.Proc. R. Soc. Edinb., Sect. A, Math. 141 (2011), 1175-1206. MR 2855893 | 
| Reference:
             | 
[2] Chernyavskaya, N., Shuster, L.: A criterion for correct solvability in $L_p(\mathbb R)$ of a general Sturm-Liouville equation.J. Lond. Math. Soc., II. Ser. 80 (2009), 99-120. MR 2520380, 10.1112/jlms/jdp012 | 
| Reference:
             | 
[3] Chernyavskaya, N., Shuster, L.: A criterion for correct solvability of the Sturm-Liouville equation in the space $L_p(R)$.Proc. Am. Math. Soc. 130 (2002), 1043-1054. Zbl 0994.34014, MR 1873778, 10.1090/S0002-9939-01-06145-7 | 
| Reference:
             | 
[4] Chernyavskaya, N., Shuster, L.: Regularity of the inversion problem for a Sturm-Liouville equation in $L_p(\mathbb R)$.Methods Appl. Anal. 7 (2000), 65-84. MR 1796006 | 
| Reference:
             | 
[5] Chernyavskaya, N., Shuster, L.: Estimates for the Green function of a general Sturm-Liouville operator and their applications.Proc. Am. Math. Soc. 127 (1999), 1413-1426. Zbl 0918.34032, MR 1625725, 10.1090/S0002-9939-99-05049-2 | 
| Reference:
             | 
[6] Chernyavskaya, N., Shuster, L.: Solvability in $L_p$ of the Neumann problem for a singular non-homogeneous Sturm-Liouville equation.Mathematika 46 (1999), 453-470. MR 1832636, 10.1112/S0025579300007919 | 
| Reference:
             | 
[7] Chernyavskaya, N., Shuster, L.: Solvability in $L_p$ of the Dirichlet problem for a singular nonhomogeneous Sturm-Liouville equation.Methods Appl. Anal. 5 (1998), 259-272. Zbl 0924.34012, MR 1659147 | 
| Reference:
             | 
[8] Mynbaev, K. T., Otelbaev, M. O.: Weighted Function Spaces and the Spectrum of Differential Operators.Nauka, Moskva Russian (1988). MR 0950172 | 
| Reference:
             | 
[9] Titchmarsh, E. C.: The Theory of Functions. (2. ed.).University Press, Oxford (1939). MR 0197687 | 
| . |