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            <front>

                <journal-meta>
                                                                <journal-id>ieja</journal-id>
            <journal-title-group>
                                                                                    <journal-title>International Electronic Journal of Algebra</journal-title>
            </journal-title-group>
                            <issn pub-type="ppub">1306-6048</issn>
                                                                                                        <publisher>
                    <publisher-name>Abdullah HARMANCI</publisher-name>
                </publisher>
                    </journal-meta>
                <article-meta>
                                        <article-id pub-id-type="doi">10.24330/ieja.440239</article-id>
                                                                <article-categories>
                                            <subj-group  xml:lang="en">
                                                            <subject>Mathematical Sciences</subject>
                                                    </subj-group>
                                            <subj-group  xml:lang="tr">
                                                            <subject>Matematik</subject>
                                                    </subj-group>
                                    </article-categories>
                                                                                                                                                        <title-group>
                                                                                                                                                            <article-title>A CATEGORICAL APPROACH TO ALGEBRAS AND COALGEBRAS</article-title>
                                                                                                    </title-group>
            
                                                    <contrib-group content-type="authors">
                                                                        <contrib contrib-type="author">
                                                                <name>
                                    <surname>Wisbauer</surname>
                                    <given-names>Robert</given-names>
                                </name>
                                                            </contrib>
                                                                                </contrib-group>
                        
                                        <pub-date pub-type="pub" iso-8601-date="20180705">
                    <day>07</day>
                    <month>05</month>
                    <year>2018</year>
                </pub-date>
                                        <volume>24</volume>
                                        <issue>24</issue>
                                        <fpage>153</fpage>
                                        <lpage>173</lpage>
                        
                        <history>
                                    <date date-type="received" iso-8601-date="20171219">
                        <day>12</day>
                        <month>19</month>
                        <year>2017</year>
                    </date>
                                            </history>
                                        <permissions>
                    <copyright-statement>Copyright © 2007, International Electronic Journal of Algebra</copyright-statement>
                    <copyright-year>2007</copyright-year>
                    <copyright-holder>International Electronic Journal of Algebra</copyright-holder>
                </permissions>
            
                                                                                                                        <abstract><p>Algebraic and coalgebraic structures are often handled independently.In this survey we want to show that they both show up naturally whenapproaching them from a categorical point of view. Azumaya, Frobenius, separable,and Hopf algebras are obtained when both notions are combined. Thestarting point and guiding lines for this approach are given by adjoint pairs offunctors and their elementary properties.</p></abstract>
                                                            
            
                                                                                        <kwd-group>
                                                    <kwd>(Co)algebras</kwd>
                                                    <kwd>  (co)monads</kwd>
                                                    <kwd>  Frobenius algebras</kwd>
                                                    <kwd>  separable algebras</kwd>
                                                    <kwd>  Hopf algebras</kwd>
                                            </kwd-group>
                            
                                                                                                                                                    </article-meta>
    </front>
    <back>
                            <ref-list>
                                    <ref id="ref1">
                        <label>1</label>
                        <mixed-citation publication-type="journal">J. Beck, Distributive laws, in Seminar on Triples and Categorical Homology
Theory, B. Eckmann (ed.), Springer, Berlin, 80 (1969), 119-140.</mixed-citation>
                    </ref>
                                    <ref id="ref2">
                        <label>2</label>
                        <mixed-citation publication-type="journal">G. Bohm, T. Brzezinski and R. Wisbauer, Monads and comonads on module
categories, J. Algebra, 322(5) (2009), 1719-1747.</mixed-citation>
                    </ref>
                                    <ref id="ref3">
                        <label>3</label>
                        <mixed-citation publication-type="journal">T. Brzezinski and R. Wisbauer, Corings and Comodules, London Mathematical
Society Lecture Note Series, 309, Cambridge University Press, Cambridge,
2003.</mixed-citation>
                    </ref>
                                    <ref id="ref4">
                        <label>4</label>
                        <mixed-citation publication-type="journal">J. Clark and R. Wisbauer, Idempotent monads and ?-functors, J. Pure Appl.
Algebra, 215(2) (2011), 145-153.</mixed-citation>
                    </ref>
                                    <ref id="ref5">
                        <label>5</label>
                        <mixed-citation publication-type="journal">S. Eilenberg and S. Mac Lane, General theory of natural equivalences, Trans.
Amer. Math. Soc., 58(2) (1945), 231-294.</mixed-citation>
                    </ref>
                                    <ref id="ref6">
                        <label>6</label>
                        <mixed-citation publication-type="journal">S. Eilenberg and J. C. Moore, Adjoint functors and triples, Illinois. J. Math.,
9 (1965), 381-398.</mixed-citation>
                    </ref>
                                    <ref id="ref7">
                        <label>7</label>
                        <mixed-citation publication-type="journal">F. Frobenius, Theorie der hypercomplexen Groben, Sitz. Kon. Preuss. Akad.
Wiss., (1903), 504-537; Gesammelte Abhandlungen, art. 70, 284-317.</mixed-citation>
                    </ref>
                                    <ref id="ref8">
                        <label>8</label>
                        <mixed-citation publication-type="journal">H. Hopf,  Uber die Topologie der Gruppen-Mannigfaltigkeiten und ihre
Verallgemeinerungen, Ann. of Math., 42(2) (1941), 22-52.</mixed-citation>
                    </ref>
                                    <ref id="ref9">
                        <label>9</label>
                        <mixed-citation publication-type="journal">S. O. Ivanov, Nakayama functors and Eilenberg-Watts theorems, J. Math. Sci.,
183(5) (2012), 675-680.</mixed-citation>
                    </ref>
                                    <ref id="ref10">
                        <label>10</label>
                        <mixed-citation publication-type="journal">D. M. Kan, Adjoint functors, Trans. Amer. Math. Soc., 87 (1958), 294-329.</mixed-citation>
                    </ref>
                                    <ref id="ref11">
                        <label>11</label>
                        <mixed-citation publication-type="journal">H. Kleisli, Every standard construction is induced by a pair of adjoint functors,
Proc. Amer. Math. Soc., 16 (1965), 544-546.</mixed-citation>
                    </ref>
                                    <ref id="ref12">
                        <label>12</label>
                        <mixed-citation publication-type="journal">S. Mac Lane, Categories for the Working Mathematician, 2nd edn, Graduate
Texts in Mathematics, 5, Springer-Verlag, New York, 1998.</mixed-citation>
                    </ref>
                                    <ref id="ref13">
                        <label>13</label>
                        <mixed-citation publication-type="journal">R. Marczinzik, A bocs theoretic characterization of gendo-symmetric algebras,
J. Algebra, 470 (2017), 160-171.</mixed-citation>
                    </ref>
                                    <ref id="ref14">
                        <label>14</label>
                        <mixed-citation publication-type="journal">B. Mesablishvili, Entwining structures in monoidal categories, J. Algebra,
319(6) (2008), 2496-2517.</mixed-citation>
                    </ref>
                                    <ref id="ref15">
                        <label>15</label>
                        <mixed-citation publication-type="journal">B. Mesablishvili and R. Wisbauer, Galois functors and entwining structures,
J. Algebra, 324(3) (2010), 464-506.</mixed-citation>
                    </ref>
                                    <ref id="ref16">
                        <label>16</label>
                        <mixed-citation publication-type="journal">B. Mesablishvili and R. Wisbauer, Bimonads and Hopf monads on categories,
J. K-Theory, 7(2) (2011), 349-388.</mixed-citation>
                    </ref>
                                    <ref id="ref17">
                        <label>17</label>
                        <mixed-citation publication-type="journal">B. Mesablishvili and R. Wisbauer, Notes on bimonads and Hopf monads, Theory
Appl. Categ., 26(10) (2012), 281-303.</mixed-citation>
                    </ref>
                                    <ref id="ref18">
                        <label>18</label>
                        <mixed-citation publication-type="journal">B. Mesablishvili and R. Wisbauer, QF functors and (co)monads, J. Algebra,
376 (2013), 101-122.</mixed-citation>
                    </ref>
                                    <ref id="ref19">
                        <label>19</label>
                        <mixed-citation publication-type="journal">B. Mesablishvili and R. Wisbauer, The fundamental theorem for weak braided
bimonads, J. Algebra, 490 (2017), 55-103.</mixed-citation>
                    </ref>
                                    <ref id="ref20">
                        <label>20</label>
                        <mixed-citation publication-type="journal">J. W. Milnor and J. C. Moore, On the structure of Hopf algebras, Ann. of
Math., 81(2) (1965), 211-264.</mixed-citation>
                    </ref>
                                    <ref id="ref21">
                        <label>21</label>
                        <mixed-citation publication-type="journal">K. Morita, Duality for modules and its applications to the theory of rings with
minimum condition, Sci. Rep. Tokyo Kyoiku Daigaku Sect. A, 6 (1958), 83-142.</mixed-citation>
                    </ref>
                                    <ref id="ref22">
                        <label>22</label>
                        <mixed-citation publication-type="journal">A. V. Roiter, Matrix problems and representations of BOCSs, Representation
Theory I, Lecture Notes in Math., 831, Springer, Berlin-New York, (1980),
288-324.</mixed-citation>
                    </ref>
                                    <ref id="ref23">
                        <label>23</label>
                        <mixed-citation publication-type="journal">M. Sato, Fuller&#039;s theorem on equivalences, J. Algebra, 52(1) (1978), 274-284.</mixed-citation>
                    </ref>
                                    <ref id="ref24">
                        <label>24</label>
                        <mixed-citation publication-type="journal">M. Sato, On equivalences between module subcategories, J. Algebra, 59(2)
(1979), 412-420.</mixed-citation>
                    </ref>
                                    <ref id="ref25">
                        <label>25</label>
                        <mixed-citation publication-type="journal">R. Street, Frobenius monads and pseudomonoids, J. Math. Phys., 45(10)
(2004), 3930-3948.</mixed-citation>
                    </ref>
                                    <ref id="ref26">
                        <label>26</label>
                        <mixed-citation publication-type="journal">D. Turi and G. Plotkin, Towards a mathematical operational semantics, Proceedings
12th Ann. IEEE Symp. on Logic in Computer Science, LICS&#039;97, Warsaw,
Poland, (1997).</mixed-citation>
                    </ref>
                                    <ref id="ref27">
                        <label>27</label>
                        <mixed-citation publication-type="journal">R. Wisbauer, Foundations of Module and Ring Theory, Algebra, Logic and
Applications, 3, Gordon and Breach Science Publishers, Philadelphia, PA,
1991.</mixed-citation>
                    </ref>
                                    <ref id="ref28">
                        <label>28</label>
                        <mixed-citation publication-type="journal">R. Wisbauer, Tilting in module categories, Abelian groups, module theory, and
topology (Padua, 1997), Lecture Notes in Pure and Appl. Math., 201, Dekker,
New York, (1998), 421-444.</mixed-citation>
                    </ref>
                                    <ref id="ref29">
                        <label>29</label>
                        <mixed-citation publication-type="journal">R. Wisbauer, Static modules and equivalences, Interactions between ring theory
and representations of algebras (Murcia), Lecture Notes in Pure and Appl.
Math., 210, Dekker, New York, (2000), 423-449.</mixed-citation>
                    </ref>
                                    <ref id="ref30">
                        <label>30</label>
                        <mixed-citation publication-type="journal">R. Wisbauer, Algebra versus coalgebras, Appl. Categ. Structures, 16 (2008),
255-295.</mixed-citation>
                    </ref>
                                    <ref id="ref31">
                        <label>31</label>
                        <mixed-citation publication-type="journal">R. Wisbauer, Comodules and contramodules, Glasg. Math. J., 52(A) (2010),
151-162.</mixed-citation>
                    </ref>
                                    <ref id="ref32">
                        <label>32</label>
                        <mixed-citation publication-type="journal">R. Wisbauer, Regular pairings of functors and weak (co)monads, Algebra Discrete
Math., 15(1) (2013), 127-154.</mixed-citation>
                    </ref>
                                    <ref id="ref33">
                        <label>33</label>
                        <mixed-citation publication-type="journal">R. Wisbauer, Weak Frobenius monads and Frobenius bimodules, Algebra Discrete
Math., 21(2) (2016), 287-308.</mixed-citation>
                    </ref>
                                    <ref id="ref34">
                        <label>34</label>
                        <mixed-citation publication-type="journal">R. Wisbauer, Separability in algebra and category theory, Proc. Aligarh, (2016).</mixed-citation>
                    </ref>
                                    <ref id="ref35">
                        <label>35</label>
                        <mixed-citation publication-type="journal">J. Worthington, A bialgebraic approach to automata and formal language theory,
Ann. Pure Appl. Logic, 163(7) (2012), 745-762.</mixed-citation>
                    </ref>
                            </ref-list>
                    </back>
    </article>
