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EXPANDING THE REALS BY CONTINUOUS FUNCTIONS ADDS NO COMPUTATIONAL POWER

Published online by Cambridge University Press:  26 September 2022

URI ANDREWS
Affiliation:
DEPARTMENT OF MATHEMATICS UNIVERSITY OF WISCONSIN–MADISON, MADISON, WI, USA E-mail: andrews@math.wisc.edu E-mail: jmiller@math.wisc.edu
JULIA F. KNIGHT
Affiliation:
DEPARTMENT OF MATHEMATICS UNIVERSITY OF NOTRE DAME, SOUTH BEND, IN, USA E-mail: Julia.F.Knight.1@nd.edu
RUTGER KUYPER
Affiliation:
METASWITCH WELLINGTON, NEW ZEALAND E-mail: mail@rutgerkuyper.com
JOSEPH S. MILLER
Affiliation:
DEPARTMENT OF MATHEMATICS UNIVERSITY OF WISCONSIN–MADISON, MADISON, WI, USA E-mail: andrews@math.wisc.edu E-mail: jmiller@math.wisc.edu
MARIYA I. SOSKOVA*
Affiliation:
DEPARTMENT OF MATHEMATICS UNIVERSITY OF WISCONSIN–MADISON, MADISON, WI, USA E-mail: andrews@math.wisc.edu E-mail: jmiller@math.wisc.edu

Abstract

We study the relative computational power of structures related to the ordered field of reals, specifically using the notion of generic Muchnik reducibility. We show that any expansion of the reals by a continuous function has no more computing power than the reals, answering a question of Igusa, Knight, and Schweber [7]. On the other hand, we show that there is a certain Borel expansion of the reals that is strictly more powerful than the reals and such that any Borel quotient of the reals reduces to it.

Type
Article
Copyright
© The Author(s), 2022. Published by Cambridge University Press on behalf of The Association for Symbolic Logic

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References

Allen, K., Bienvenu, L., and Slaman, T. A., On zeros of Martin-Löf random Brownian motion . Journal of Logic and Analysis , vol. 6 (2014), Article no. 9, 34 pp.Google Scholar
Andrews, U., Miller, J. S., Schweber, N. D., and Soskova, M. I., Complexity profiles and generic Muchnik reducibility, submitted. Available at https://people.math.wisc.edu/jmiller/Papers/GenericMuchnik3.pdf.Google Scholar
Downey, R., Greenberg, N., and Miller, J. S., Generic Muchnik reducibility and presentations of fields . Israel Journal of Mathematics , vol. 216 (2016), no. 1, pp. 371387.CrossRefGoogle Scholar
Hjorth, G., Khoussainov, B., Montalbán, A., and Nies, A., From automatic structures to Borel structures , Proceedings of the Twenty-Third Annual IEEE Symposium on Logic in Computer Science (LICS 2008) , IEEE Computer Society, 2008, pp. 431441.10.1109/LICS.2008.28CrossRefGoogle Scholar
Hjorth, G. and Nies, A., Borel structures and Borel theories, this Journal, vol. 76 (2011), no. 2, pp. 461–476.Google Scholar
Igusa, G. and Knight, J. F., Comparing two versions of the reals, this Journal, vol. 81 (2016), no. 3, pp. 1115–1123.Google Scholar
Igusa, G., Knight, J. F., and Schweber, N. D., Computing strength of structures related to the field of real numbers, this Journal, vol. 82 (2017), no. 1, pp. 137–150.Google Scholar
Jockusch, C. G. Jr. and Soare, R. I., ${\varPi}_1^0$ classes and degrees of theories . Transactions of the American Mathematical Society , vol. 173 (1972), pp. 3356.Google Scholar
Knight, J. F., Montalbán, A., and Schweber, N. D., Computable structures in generic extensions, this Journal, vol. 81 (2016), no. 3, pp. 814–832.Google Scholar
Louveau, A., Classifying Borel structures , Set Theory and the Continuum (Meeting at Berkeley, 1989) (Judah, H., Just, W., and Woodin, H., editors), Mathematical Sciences Research Institute Publications, vol 26, Springer, New York, 1989, pp. 103112.CrossRefGoogle Scholar
MacIntyre, A. and Marker, D., Degrees of recursively saturated models . Transactions of the American Mathematical Society , vol. 282 (1984), no. 2, pp. 539554.10.1090/S0002-9947-1984-0732105-5CrossRefGoogle Scholar
Montalbán, A., Notes on the jump of a structure , Mathematical Theory and Computational Practice , Lecture Notes in Computer Science, vol. 5635, Springer, Berlin, 2009, pp. 372378.10.1007/978-3-642-03073-4_38CrossRefGoogle Scholar
Montalbán, A., A fixed point for the jump operator on structures, this Journal, vol. 78 (2013), no. 2, pp. 425438.Google Scholar
Montalbán, A. and Nies, A., Borel structures: A brief survey , Effective Mathematics of the Uncountable (Greenberg, N., Hirschfeldt, D., Hamkins, J. D., and Miller, R., editors), Lecture Notes in Logic, vol. 41, Association for Symbolic Logic, La Jolla, 2013, pp. 124134.CrossRefGoogle Scholar
Moschovakis, Y. N., Abstract first order computability. I, II. Transactions of the American Mathematical Society , vol. 138 (1969), pp. 427464.Google Scholar
Puzarenko, V. G., On a certain reducibility on admissible sets . Sibirskii Matematicheskii Zhurnal , vol. 50 (2009), no. 2, pp. 415429.Google Scholar
Puzarenko, V. G., Fixed points for the jump operator . Algebra Logika , vol. 50 (2011), no. 5, pp. 615646, 693, 695.CrossRefGoogle Scholar
Shoenfield, J. R., The problem of predicativity , Essays on the Foundations of Mathematics , Magnes Press and Hebrew University, Jerusalem, 1961, pp. 132139.Google Scholar
Soskova, A. A., A jump inversion theorem for the degree spectra , Computation and Logic in the Real World (Cooper, S. B., Löwe, B., and Sorbi, A., editors), Lecture Notes in Computer Science, vol. 4497, Springer, Berlin, 2007, pp. 716726.CrossRefGoogle Scholar
Soskova, A. A. and Soskov, I. N., A jump inversion theorem for the degree spectra . Journal of Logic and Computation , vol. 19 (2009), no. 1, pp. 199215.CrossRefGoogle Scholar
Steinhorn, C., Borel structures for first-order and extended logics , Harvey Friedman’s Research on the Foundations of Mathematics (Harrington, A., Morley, M. D., ŠĊedrov, A., and Simpson, S. G., editors), Studies in Logic and the Foundations of Mathematics, vol. 117, North-Holland, Amsterdam, 1985, pp. 161178.CrossRefGoogle Scholar
Steinhorn, C. I., Borel structures and measure and category logics , Model-Theoretic Logics (Barwise, J. and Feferman, S., editors), Perspectives in Mathematical Logic, Springer, New York, 1985, pp. 579596.Google Scholar
Stukachev, A. I., A jump inversion theorem for the semilattices of Sigma-degrees. Siberian Advances in Mathematics , vol. 20 (2010), no. 1, pp. 6874.CrossRefGoogle Scholar