Available in electronic format
Available in print format
Transactions of the American Mathematical Society
Transactions of the American Mathematical Society
ISSN 1088-6850(e) ISSN 0002-9947(p)
     

On the averages of Darboux functions

Author(s): Aleksander Maliszewski
Journal: Trans. Amer. Math. Soc. 350 (1998), 2833-2846.
MSC (1991): Primary 26A21, 54C30.; Secondary 26A15, 54C08
Retrieve article in: PDF
This article is available free of charge

Abstract | References | Similar articles | Additional information

Abstract: Let $\mathbf{A} $ be the family of functions which can be written as the average of two comparable Darboux functions. In 1974 A. M. Bruckner, J. G. Ceder, and T. L. Pearson characterized the family $\mathbf{A}  $ and showed that if $\alpha \ge 2$, then $\mathbf{A} \cap {\mathbf B}_\alpha$ is the family of the averages of comparable Darboux functions in Baire class $\alpha$. They also asked whether the latter result holds true also for $\alpha =1$. The main goal of this paper is to answer this question in the negative and to characterize the family of the averages of comparable Darboux Baire one functions.


References:

1.
J. B. Brown, Almost continuous Darboux functions and Reed's pointwise convergence criteria, Fund. Math. 86 (1974), 1-7. MR 50:4845
2.
A. M. Bruckner, Differentiation of real functions, Lecture Notes in Math., no. 659, Springer Verlag, 1978. MR 80h:26002
3.
A. M. Bruckner and J. G. Ceder, Darboux continuity, Jahresber. Deutsch. Math.-Verein. 67 (1965), 93-117. MR 32:4217
4.
A. M. Bruckner, J. G. Ceder, and T. L. Pearson, On Darboux functions, Rev. Roumaine Math. Pures Appl. 19 (1974), no. 3, 977-988. MR 50:4846
5.
A. M. Bruckner and J. L. Leonard, Stationary sets and determining sets for certain classes of Darboux functions, Proc. Amer. Math. Soc. 16 (1965), 935-940. MR 32:1303
6.
J. G. Ceder, Differentiable roads for real functions, Fund. Math. 65 (1969), 351-358. MR 40:4398
7.
J. G. Ceder and T. L. Pearson, Insertion of open functions, Duke Math. J. 35 (1968), 277-288. MR 36:6556
8.
-, A survey of Darboux Baire $1$ functions, Real Anal. Exchange 9 (1983-84), no. 1, 179-194. MR 86a:26003
9.
K. Ciesielski and A. W. Miller, Cardinal invariants concerning functions whose sum is almost continuous, Real Anal. Exchange 20 (1994-95), no. 2, 657-672. MR 96h:26003
10.
Z. Grande, On the Darboux property of the sum of cliquish functions, Real Anal. Exchange 17 (1991-92), no. 2, 571-576. MR 93f:26001

11.
A. Maliszewski, Sums of bounded Darboux functions, Real Anal. Exchange 20 (1994-95), no. 2, 673-680. MR 96f:26002
12.
-, On theorems of Pu & Pu and Grande, Math. Bohemica 121 (1996), no. 1, 83-87. MR 97c:26006
13.
I. Maximoff, Sur les fonctions ayant la propriété de Darboux, Prace Mat.-Fiz. 43 (1936), 241-265.
14.
-, Sur la transformation continue de fonctions, Bull. Soc. Phys. Math. Kazan 12 (1940), 9-41. MR 7:420g
15.
-, On functions of class $1$ having the property of Darboux, Amer. J. Math. 65 (1943), 161-170. MR 4:213b
16.
R. J. O'Malley, Baire* $1$, Darboux functions, Proc. Amer. Math. Soc. 60 (1976), 187-192. MR 54:5405
17.
D. Preiss, Maximoff's theorem, Real Anal. Exchange 5 (1979-80), no. 1, 92-104. MR 80m:26007
18.
J. Smítal, On approximation of Baire functions by Darboux functions, Czechoslovak Math. J. 21 (1971), no. 96, 418-423. MR 45:470
19.
J. Stallings, Fixed point theorem for connectivity maps, Fund. Math. 47 (1959), 249-263. MR 22:8485
20.
J. Young, A theorem in the theory of functions of a real variable, Rend. Circ. Mat. Palermo 24 (1907), 187-192.
21.
Z. Zahorski, Sur la première dérivée, Trans. Amer. Math. Soc. 69 (1950), 1-54. MR 12:247c


Similar Articles:

Retrieve articles in Transactions of the American Mathematical Society with MSC (1991): 26A21, 54C30., 26A15, 54C08

Retrieve articles in all Journals with MSC (1991): 26A21, 54C30., 26A15, 54C08


Additional Information:

Aleksander Maliszewski
Affiliation: Department of Mathematics, Pedagogical University, pl. Weyssenhoffa 11, 85-042 Bydgoszcz, Poland
Email: amal@wsp.bydgoszcz.pl

DOI: 10.1090/S0002-9947-98-02267-3
PII: S 0002-9947(98)02267-3
Keywords: Darboux function, comparable functions, average of functions
Received by editor(s): July 30, 1996
Additional Notes: Partially supported by NSF Cooperative Research Grant INT-9600548, with its Polish part being financed by the Polish Academy of Sciences
Copyright of article: Copyright 1998, American Mathematical Society


  AMS Website Logo Small Comments: webmaster@ams.org
© Copyright 2009, American Mathematical Society
Privacy Statement
Search the AMSPowered by Google