Constantin Apostol

662 total citations
40 papers, 418 citations indexed

About

Constantin Apostol is a scholar working on Mathematical Physics, Computational Theory and Mathematics and Applied Mathematics. According to data from OpenAlex, Constantin Apostol has authored 40 papers receiving a total of 418 indexed citations (citations by other indexed papers that have themselves been cited), including 22 papers in Mathematical Physics, 20 papers in Computational Theory and Mathematics and 20 papers in Applied Mathematics. Recurrent topics in Constantin Apostol's work include Matrix Theory and Algorithms (19 papers), Holomorphic and Operator Theory (17 papers) and Spectral Theory in Mathematical Physics (11 papers). Constantin Apostol is often cited by papers focused on Matrix Theory and Algorithms (19 papers), Holomorphic and Operator Theory (17 papers) and Spectral Theory in Mathematical Physics (11 papers). Constantin Apostol collaborates with scholars based in United States, Romania and Czechia. Constantin Apostol's co-authors include Ciprian Foiaş, Carl Pearcy, Lawrence A. Fialkow, Hari Bercovici, Norberto Salinas, Kevin F. Clancey, Frank Gilfeather, R. G. Douglas, B. Nagy and Dan-Virgil Voiculescu and has published in prestigious journals such as Transactions of the American Mathematical Society, Journal of Functional Analysis and Pacific Journal of Mathematics.

In The Last Decade

Constantin Apostol

36 papers receiving 298 citations

Peers — A (Enhanced Table)

Peers by citation overlap · career bar shows stage (early→late) cites · hero ref

Name h Career Trend Papers Cites
Constantin Apostol United States 11 297 249 163 140 44 40 418
Jaroslav Zemánek Poland 12 280 0.9× 272 1.1× 138 0.8× 131 0.9× 49 1.1× 43 411
Takahiko Nakazi Japan 10 327 1.1× 154 0.6× 108 0.7× 72 0.5× 89 2.0× 83 410
Douglas N. Clark United States 11 487 1.6× 256 1.0× 145 0.9× 96 0.7× 115 2.6× 29 569
Alan Lambert United States 13 371 1.2× 268 1.1× 234 1.4× 104 0.7× 57 1.3× 39 463
Klaus Floret Germany 11 299 1.0× 430 1.7× 116 0.7× 101 0.7× 147 3.3× 36 519
Christian Le Merdy France 11 437 1.5× 586 2.4× 260 1.6× 74 0.5× 79 1.8× 61 679
Richard J. Fleming United States 10 214 0.7× 272 1.1× 185 1.1× 63 0.5× 66 1.5× 32 364
Ching Chou United States 13 146 0.5× 350 1.4× 153 0.9× 71 0.5× 208 4.7× 41 465
Richard Bouldin United States 9 199 0.7× 179 0.7× 54 0.3× 177 1.3× 24 0.5× 40 309
Colin C. Graham United States 8 189 0.6× 302 1.2× 98 0.6× 48 0.3× 142 3.2× 60 408

Countries citing papers authored by Constantin Apostol

Since Specialization
Citations

This map shows the geographic impact of Constantin Apostol's research. It shows the number of citations coming from papers published by authors working in each country. You can also color the map by specialization and compare the number of citations received by Constantin Apostol with the expected number of citations based on a country's size and research output (numbers larger than one mean the country cites Constantin Apostol more than expected).

Fields of papers citing papers by Constantin Apostol

Since Specialization
Physical SciencesHealth SciencesLife SciencesSocial Sciences

This network shows the impact of papers produced by Constantin Apostol. Nodes represent research fields, and links connect fields that are likely to share authors. Colored nodes show fields that tend to cite the papers produced by Constantin Apostol. The network helps show where Constantin Apostol may publish in the future.

Co-authorship network of co-authors of Constantin Apostol

This figure shows the co-authorship network connecting the top 25 collaborators of Constantin Apostol. A scholar is included among the top collaborators of Constantin Apostol based on the total number of citations received by their joint publications. Widths of edges represent the number of papers authors have co-authored together. Node borders signify the number of papers an author published with Constantin Apostol. Constantin Apostol is excluded from the visualization to improve readability, since they are connected to all nodes in the network.

All Works

20 of 20 papers shown
1.
Apostol, Constantin, Hari Bercovici, Ciprian Foiaş, & Carl Pearcy. (1985). Invariant subspaces, dilation theory, and the structure of the predual of a dual algebra, I. Journal of Functional Analysis. 63(3). 369–404. 61 indexed citations
2.
Apostol, Constantin. (1984). Hyperinvariant subspaces for bilateral weighted shifts. Integral Equations and Operator Theory. 7(1). 1–9. 30 indexed citations
3.
Apostol, Constantin. (1983). Dilation theory, Toeplitz operators, and other topics : 7th International Conference on Operator Theory, Timişoara and Herculane (Romania), June 7-17, 1982. Birkhäuser-Verlag eBooks. 1 indexed citations
4.
Apostol, Constantin, et al.. (1982). Invariant Subspaces and Other Topics. CERN Document Server (European Organization for Nuclear Research). 9 indexed citations
5.
6.
Apostol, Constantin, et al.. (1981). Topics in Modern Operator Theory. CERN Document Server (European Organization for Nuclear Research). 19 indexed citations
7.
Apostol, Constantin, Ciprian Foiaş, & Carl Pearcy. (1979). That quasinilpotent operators are norm-limits of nilpotent operators revisited. Proceedings of the American Mathematical Society. 73(1). 61–64. 5 indexed citations
8.
Apostol, Constantin, et al.. (1977). . Indiana University Mathematics Journal. 26(3). 427–427. 15 indexed citations
9.
Apostol, Constantin, R. G. Douglas, & Ciprian Foiaş. (1976). Quasi-similar models for nilpotent operators. Transactions of the American Mathematical Society. 224(2). 407–415. 10 indexed citations
10.
Apostol, Constantin & Kevin F. Clancey. (1976). Generalized inverses and spectral theory. Transactions of the American Mathematical Society. 215(0). 293–300. 9 indexed citations
11.
Apostol, Constantin & Kevin F. Clancey. (1976). Local Resolvents of Operators with One-Dimensional Self-Commutator. Proceedings of the American Mathematical Society. 58(1). 158–158. 2 indexed citations
12.
Apostol, Constantin & Kevin F. Clancey. (1976). Generalized Inverses and Spectral Theory. Transactions of the American Mathematical Society. 215. 293–293. 4 indexed citations
13.
Apostol, Constantin. (1976). On the operator equation 𝑇𝑋-𝑋𝑉=𝐴. Proceedings of the American Mathematical Society. 59(1). 115–118. 2 indexed citations
14.
Apostol, Constantin. (1975). Operators quasisimilar to a normal operator. Proceedings of the American Mathematical Society. 53(1). 104–106. 17 indexed citations
15.
Apostol, Constantin & C. K. Fong. (1975). Invariant subspaces for algebras generated by strongly reductive operators. Duke Mathematical Journal. 42(3). 4 indexed citations
16.
Apostol, Constantin. (1975). Matrix models for operators. Duke Mathematical Journal. 42(4). 1 indexed citations
17.
Apostol, Constantin. (1971). B ∗-Algebras and their Representation. Journal of the London Mathematical Society. s2-3(1). 30–38. 15 indexed citations
18.
Apostol, Constantin. (1968). Remarks on the perturbation and a topology for operators. Journal of Functional Analysis. 2(4). 395–408. 3 indexed citations
19.
Apostol, Constantin. (1968). Roots of scalar operator-valued analytic functions and their functional calculus. Hiroshima Mathematical Journal. 32(1). 1 indexed citations
20.
Apostol, Constantin. (1968). On the Roots of Spectral Operators. Proceedings of the American Mathematical Society. 19(4). 811–811. 2 indexed citations

Rankless uses publication and citation data sourced from OpenAlex, an open and comprehensive bibliographic database. While OpenAlex provides broad and valuable coverage of the global research landscape, it—like all bibliographic datasets—has inherent limitations. These include incomplete records, variations in author disambiguation, differences in journal indexing, and delays in data updates. As a result, some metrics and network relationships displayed in Rankless may not fully capture the entirety of a scholar's output or impact.

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