| Title:
             | 
The nil radical of an Archimedean partially ordered ring with positive squares (English) | 
| Author:
             | 
Lavrič, Boris | 
| Language:
             | 
English | 
| Journal:
             | 
Commentationes Mathematicae Universitatis Carolinae | 
| ISSN:
             | 
0010-2628 (print) | 
| ISSN:
             | 
1213-7243 (online) | 
| Volume:
             | 
35 | 
| Issue:
             | 
2 | 
| Year:
             | 
1994 | 
| Pages:
             | 
231-238 | 
| . | 
| Category:
             | 
math | 
| . | 
| Summary:
             | 
Let $R$ be an Archimedean partially ordered ring in which the square of every element is positive, and $N(R)$ the set of all nilpotent elements of $R$. It is shown that $N(R)$ is the unique nil radical of $R$, and that $N(R)$ is locally nilpotent and even nilpotent with exponent at most $3$ when $R$ is 2-torsion-free. $R$ is without non-zero nilpotents if and only if it is 2-torsion-free and has zero annihilator. The results are applied on partially ordered rings in which every element $a$ is expressed as $a=a_1-a_2$ with positive $a_1$, $a_2$ satisfying $a_1a_2=a_2a_1=0$. (English) | 
| Keyword:
             | 
partially ordered ring | 
| Keyword:
             | 
Archimedean | 
| Keyword:
             | 
nil radical | 
| Keyword:
             | 
nilpotent | 
| MSC:
             | 
06F25 | 
| MSC:
             | 
16N40 | 
| MSC:
             | 
16W80 | 
| idZBL:
             | 
Zbl 0805.06017 | 
| idMR:
             | 
MR1286569 | 
| . | 
| Date available:
             | 
2009-01-08T18:10:32Z | 
| Last updated:
             | 
2012-04-30 | 
| Stable URL:
             | 
http://hdl.handle.net/10338.dmlcz/118661 | 
| . | 
| Reference:
             | 
[1] Bernau S.J., Huijsmans C.B.: Almost $f$-algebras and $d$-algebras.Proc. Cambridge Philos. Soc. 107 (1990), 287-308. Zbl 0707.06009, MR 1027782 | 
| Reference:
             | 
[2] Birkhoff G., Pierce R.S.: Lattice-ordered rings.An. Acad. Brasil Ci\^enc. 28 (1956), 41-69. Zbl 0070.26602, MR 0080099 | 
| Reference:
             | 
[3] Diem J.E.: A radical for lattice-ordered rings.Pacific J. Math. 25 (1968), 71-82. Zbl 0157.08004, MR 0227068 | 
| Reference:
             | 
[4] Divinsky N.: Rings and Radicals.Allen, London, 1965. Zbl 0138.26303, MR 0197489 | 
| Reference:
             | 
[5] Fuchs L.: Partially Ordered Algebraic Systems.Pergamon Press, Oxford-London-New YorkParis, 1963. Zbl 0137.02001, MR 0171864 | 
| Reference:
             | 
[6] Hayes A.: A characterization of $f$-rings without non-zero nilpotents.J. London Math. Soc. 39 (1964), 706-707. Zbl 0126.06502, MR 0167501 | 
| Reference:
             | 
[7] Jacobson N.: Structure of Rings.Colloquium Publication 37, Amer. Math. Soc., Providence, 1956. Zbl 0098.25901, MR 0081264 | 
| Reference:
             | 
[8] Steinberg S.A.: On lattice-ordered rings in which the square of every element is positive.J. Austral. Math. Soc. Ser. A 22 (1976), 362-370. Zbl 0352.06017, MR 0427198 | 
| Reference:
             | 
[9] Szász F.A.: Radicals of Rings.Akademiai Kiado - John Wiley & Sons, Budapest-ChichesterNew York-Brisbane-Toronto, 1981. MR 0636787 | 
| . |