Reminiscences “Back in the Good Old Days...” column edited by George F. Corliss by Svetoslav Markov Interval functions have often been discussed in relation to Hausdorff approxima- tions  at Blagovest Sendov’s seminar on Approximation Theory held regularly in the Bulgarian Academy of Sciences since 1964. Numerical computations related to the best polynomial Hausdorff approximations of certain interval functions require special attention to round-off errors . In 1975 Sendov, who was my PhD super- visor, gave me reprints of papers by T. Sunaga, H. Ratschek and G. Schroder ¨ on interval arithmetic and differentiation of interval functions. I was very impressed by these papers, especially by the one from Sunaga, which I enjoyed studying thoroughly . It took many centuries to human mind to grasp the mystery of numbers. G. Birkhoff notes: “We should not forget that zero and negative numbers were among the last to be accepted” . The primary use of negative numbers (and zero) is to make the equation A + X = B always solvable, i.e. to make the additive semigroup (R , +) of nonnegative numbers a group. The isomorphic extension (embedding) of an Abelian semigroup into a group is now a common mathematical
Reliable Computing – Springer Journals
Published: Oct 3, 2004
It’s your single place to instantly
discover and read the research
that matters to you.
Enjoy affordable access to
over 18 million articles from more than
15,000 peer-reviewed journals.
All for just $49/month
Query the DeepDyve database, plus search all of PubMed and Google Scholar seamlessly
Save any article or search result from DeepDyve, PubMed, and Google Scholar... all in one place.
All the latest content is available, no embargo periods.
“Whoa! It’s like Spotify but for academic articles.”@Phil_Robichaud