Towards Flexiformal Mathematics By
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Study Program Handbook Society, Media and Politics
Study Program Handbook Society, Media and Politics Bachelor of Arts Subject-specific Examination Regulations for Society, Media and Politics (Fachspezifische Prüfungsordnung) The subject-specific examination regulations for Society, Media and Politics are defined by this program handbook and are valid only in combination with the General Examination Regulations for Undergraduate degree programs (General Examination Regulations = Rahmenprüfungsordnung). This handbook also contains the program-specific Study and Examination Plan (Chapter 6). Upon graduation, students in this program will receive a Bachelor of Arts (BA) degree with a scope of 180 ECTS (for specifics see Chapter 6 of this handbook). Version Valid as of Decision Details Fall 2020 – V1.1 Sep 01, 2020 Approved by the V1 Master version Academic Senate on V1.1 Editorial Changes, June 26, 2019. indicative literature added Contents 1 Program Overview ..................................................................................................... 5 Concept .................................................................................................................................... 5 1.1.1 The Jacobs University Educational Concept..................................................................... 5 1.1.2 Program Concept ............................................................................................................. 6 Specific Advantages of SMP at Jacobs University .................................................................... 7 Program-Specific Educational -
The Future Starts Here
THE FUTURE STARTS HERE SUCCESSES EXPECTATIONS DEVELOPMENTS Custom-tailored medication, better Living diversity, using networks, Space scientist, Facebook star, batteries, the power of positive think- having better training opportunities: award-winning IT entrepreneur: ing: the things Jacobs University’s the things Jacobs University’s What Jacobs University’s researchers are studying. employees look forward to. graduates have become. Pages 4-7 Pages 8-9 Pages 10-13 WWW.JACOBS-UNIVERSITY.DE THE FUTURE STARTS HERE THE FUTURE STARTS HERE THE CASE FOR ,, ,, ACADEMIC FREEDOM It was a strong, dedicated, encouraging presentation: “Never before have there been so many opportunities for making discoveries as there are now”, said Professor Randy Schekman. Academia has never been so strong, and no temporary political influence can stop the advances in and Open to the world, transfer of knowledge. The biochemist, who together with I believe in two other scientists received the medical Nobel prize for his discoveries in cell transport processes, was awarded an communicative, honorary doctorate by Jacobs University at the graduation Jacobs University’s ceremony in 2017, at which he thanked the University in a receptive to new much-applauded speech. philosophy. ideas – that is how Schekman had already argued for free access to scientific Students get so knowledge the evening before the ceremony in a panel Bremen has always debate at Jacobs University. This is now at risk, as a small much more than Dear reader, club of scientific journals controls and limits the publication of important findings. In order to change this, the American been, and how it “The future starts here” – Jacobs University lives by this motto. -
Chapter 1 Preliminaries
Chapter 1 Preliminaries 1.1 First-order theories In this section we recall some basic definitions and facts about first-order theories. Most proofs are postponed to the end of the chapter, as exercises for the reader. 1.1.1 Definitions Definition 1.1 (First-order theory) —A first-order theory T is defined by: A first-order language L , whose terms (notation: t, u, etc.) and formulas (notation: φ, • ψ, etc.) are constructed from a fixed set of function symbols (notation: f , g, h, etc.) and of predicate symbols (notation: P, Q, R, etc.) using the following grammar: Terms t ::= x f (t1,..., tk) | Formulas φ, ψ ::= t1 = t2 P(t1,..., tk) φ | | > | ⊥ | ¬ φ ψ φ ψ φ ψ x φ x φ | ⇒ | ∧ | ∨ | ∀ | ∃ (assuming that each use of a function symbol f or of a predicate symbol P matches its arity). As usual, we call a constant symbol any function symbol of arity 0. A set of closed formulas of the language L , written Ax(T ), whose elements are called • the axioms of the theory T . Given a closed formula φ of the language of T , we say that φ is derivable in T —or that φ is a theorem of T —and write T φ when there are finitely many axioms φ , . , φ Ax(T ) such ` 1 n ∈ that the sequent φ , . , φ φ (or the formula φ φ φ) is derivable in a deduction 1 n ` 1 ∧ · · · ∧ n ⇒ system for classical logic. The set of all theorems of T is written Th(T ). Conventions 1.2 (1) In this course, we only work with first-order theories with equality. -
Documents with Flexible Notation Contexts As Interfaces To
Documents with flexible Notation Contexts as Interfaces to Mathematical Knowledge Michael Kohlhase, Christine Muller,¨ Normen Muller¨ Computer Science, Jacobs University Bremen, Germany m.kohlhase/c.mueller/[email protected] In this paper we explore the use of documents as interfaces to mathematical knowledge. We propose an augmented document model that facilitates the explication of a document’s notation context, i.e. the selection of appropriate presentations for all symbols in the docu- ment. By separating the notation context from the structure and content of a document, we aim at identifying the author’s selection of notation, i.e. his notation practices. This facili- tates both, the identification of communities of practice (COP) that share specific notation preferences and, conversely, the adaptation of documents to the notation preferences of iden- tified COPs, e.g. groups of readers and co-authors. Furthermore, explicating a document’s notation context allows for referencing and, particularly, reusing contexts, which reduces the author’s workload during the authoring process. 1 Introduction In this paper we will re-evaluate the concept of a document in the age of digital media. Since the development of writing, documents have become one of the primary means of passing on knowledge. If we take the view that knowledge is a state of the (human) mind where concepts and experiences are highly interlinked, and interpret “documents” broadly to include spoken language or action sequences played out1, then we can see that documents are almost the only means to communicate knowledge: quite literally, documents are interfaces to knowledge. Here, we will look at mathematical documents as interfaces to mathematical knowledge, since they have special complexities that reveal the underlying nature of documents and knowledge. -
Automated ZFC Theorem Proving with E
Automated ZFC Theorem Proving with E John Hester Department of Mathematics, University of Florida, Gainesville, Florida, USA https://people.clas.ufl.edu/hesterj/ [email protected] Abstract. I introduce an approach for automated reasoning in first or- der set theories that are not finitely axiomatizable, such as ZFC, and describe its implementation alongside the automated theorem proving software E. I then compare the results of proof search in the class based set theory NBG with those of ZFC. Keywords: ZFC · ATP · E. 1 Introduction Historically, automated reasoning in first order set theories has faced a fun- damental problem in the axiomatizations. Some theories such as ZFC widely considered as candidates for the foundations of mathematics are not finitely axiomatizable. Axiom schemas such as the schema of comprehension and the schema of replacement in ZFC are infinite, and so cannot be entirely incorpo- rated in to the prover at the beginning of a proof search. Indeed, there is no finite axiomatization of ZFC [1]. As a result, when reasoning about sufficiently strong set theories that could no longer be considered naive, some have taken the alternative approach of using extensions of ZFC that admit objects such as proper classes as first order objects, but this is not without its problems for the individual interested in proving set-theoretic propositions. As an alternative, I have programmed an extension to the automated the- orem prover E [2] that generates instances of parameter free replacement and comprehension from well formuled formulas of ZFC that are passed to it, when eligible, and adds them to the proof state while the prover is running. -
(Aka “Geometric”) Iff It Is Axiomatised by “Coherent Implications”
GEOMETRISATION OF FIRST-ORDER LOGIC ROY DYCKHOFF AND SARA NEGRI Abstract. That every first-order theory has a coherent conservative extension is regarded by some as obvious, even trivial, and by others as not at all obvious, but instead remarkable and valuable; the result is in any case neither sufficiently well-known nor easily found in the literature. Various approaches to the result are presented and discussed in detail, including one inspired by a problem in the proof theory of intermediate logics that led us to the proof of the present paper. It can be seen as a modification of Skolem's argument from 1920 for his \Normal Form" theorem. \Geometric" being the infinitary version of \coherent", it is further shown that every infinitary first-order theory, suitably restricted, has a geometric conservative extension, hence the title. The results are applied to simplify methods used in reasoning in and about modal and intermediate logics. We include also a new algorithm to generate special coherent implications from an axiom, designed to preserve the structure of formulae with relatively little use of normal forms. x1. Introduction. A theory is \coherent" (aka \geometric") iff it is axiomatised by \coherent implications", i.e. formulae of a certain simple syntactic form (given in Defini- tion 2.4). That every first-order theory has a coherent conservative extension is regarded by some as obvious (and trivial) and by others (including ourselves) as non- obvious, remarkable and valuable; it is neither well-enough known nor easily found in the literature. We came upon the result (and our first proof) while clarifying an argument from our paper [17]. -
1.4 Theories
1.4 Theories Before we start to work with one of the most central notions of mathematical logic – that of a theory – it will be useful to make some observations about countable sets. Lemma 1.3. 1. A set X is countable iff there is a surjection ψ : N X. 2. If X is countable and Y X then Y is countable. 3. If X and Y are countable, then X Y is countable. 4. If X and Y are countable, then X ¢ Y is countable. k 5. If X is countable and k 1 then X is countable. ä 6. If Xi is countable for each i È N, then Xi is countable. iÈN 7. If X is countable, then ä Xk is countable. k ÈN Ø Ù Proof. 1. If X is countably infinite note that every bijection is a surjection. If X x0,...,xn Õ Ô Õ is finite, let ψ Ôi xi for 0 i n and ψ j xn for j n. For the other direction, Ô Õ Ô Õ Ô Õ Ù let ψ be a surjection, then X is Øψ 0 , ψ 1 , ψ 2 ,... and removing duplicates from the Ô ÕÕ Ô N sequence ψ i i¥0 yields a bijective ϕ : X. È 2. Obvious if Y is finite. Otherwise, let ϕ : N X be a bijection and let y0 Y . Define " Õ Ô Õ È ϕÔn if ϕ n Y ψ : N Y,n y0 otherwise which is a surjection. 3. Let ϕ : N X and ψ : N Y be bijections. -
Editing Knowledge in Large Mathematical Corpora. a Case Study with Semantic LATEX(STEX)
Editing Knowledge in Large Mathematical Corpora. A case study with Semantic LATEX(STEX). Constantin Jucovschi Computer Science Jacobs University Bremen Supervisor: Prof. Dr. Michael Kohlhase arXiv:1010.5935v1 [cs.DL] 28 Oct 2010 A thesis submitted for the degree of Master of Science 2010 August Declaration The research subsumed in this thesis has been conducted under the supervision of Prof. Dr. Michael Kohlhase from Jacobs University Bremen. All material presented in this Master Thesis is my own, unless specifically stated. I, Constantin Jucovschi, hereby declare, that, to the best of my knowl- edge, the research presented in this Master Thesis contains original and independent results, and it has not been submitted elsewhere for the conferral of a degree. Constantin Jucovschi, Bremen, August 23rd, 2010 Acknowledgements I would like to thank my supervisor, Prof. Dr. Michael Kohlhase, for the opportunity to do great research with him, for the guidance I have received for the past 3 years and for his genuine interest in finding the topic I \tick for". I want to thank him for the great deal of support and understanding he showed when it came to more personal matters. I could not be happier to have Prof. Dr. Kohlhase as supervisor for my doctoral studies. I would also like to thank the members of the KWARC group for creating such a motivating and in the same time pleasant research environment. Thank you for all the questions, hints and discussions { they helped a lot; and special thanks for the ability to interact with you also outside academic environment. I would like to express my appreciation and gratitude to my family, for their long-term engagement to support and encourage me in all my beginnings. -
Lipics-FSCD-2021-29.Pdf (0.9
On the Logical Strength of Confluence and Normalisation for Cyclic Proofs Anupam Das ! Ï University of Birmingham, UK Abstract In this work we address the logical strength of confluence and normalisation for non-wellfounded typing derivations, in the tradition of “cyclic proof theory” . We present a circular version CT of Gödel’ s system T, with the aim of comparing the relative expressivity of the theories CT and T. We approach this problem by formalising rewriting-theoretic results such as confluence and normalisation for the underlying “coterm” rewriting system of CT within fragments of second-order arithmetic. We establish confluence of CT within the theory RCA0, a conservative extension of primitive recursive arithmetic and IΣ1. This allows us to recast type structures of hereditarily recursive operations as “coterm” models of T. We show that these also form models of CT, by formalising a totality argument for circular typing derivations within suitable fragments of second-order arithmetic. Relying on well-known proof mining results, we thus obtain an interpretation of CT into T; in fact, more precisely, we interpret level-n-CT into level-(n + 1)-T, an optimum result in terms of abstraction complexity. A direct consequence of these model-theoretic results is weak normalisation for CT. As further results, we also show strong normalisation for CT and continuity of functionals computed by its type 2 coterms. 2012 ACM Subject Classification Theory of computation → Equational logic and rewriting; Theory of computation → Proof theory; Theory of computation → Higher order logic; Theory of computation → Lambda calculus Keywords and phrases confluence, normalisation, system T, circular proofs, reverse mathematics, type structures Digital Object Identifier 10.4230/LIPIcs.FSCD.2021.29 Related Version This work is based on part of the following preprint, where related results, proofs and examples may be found. -
Inseparability and Conservative Extensions of Description Logic Ontologies: a Survey
Inseparability and Conservative Extensions of Description Logic Ontologies: A Survey Elena Botoeva1, Boris Konev2, Carsten Lutz3, Vladislav Ryzhikov1, Frank Wolter2, and Michael Zakharyaschev4 1 Free University of Bozen-Bolzano, Italy fbotoeva,[email protected] 2 University of Liverpool, UK fkonev,[email protected] 3 University of Bremen, Germany [email protected] 4 Birkbeck, University of London, UK [email protected] Abstract. The question whether an ontology can safely be replaced by another, possibly simpler, one is fundamental for many ontology engi- neering and maintenance tasks. It underpins, for example, ontology ver- sioning, ontology modularization, forgetting, and knowledge exchange. What `safe replacement' means depends on the intended application of the ontology. If, for example, it is used to query data, then the answers to any relevant ontology-mediated query should be the same over any relevant data set; if, in contrast, the ontology is used for conceptual reasoning, then the entailed subsumptions between concept expressions should coincide. This gives rise to different notions of ontology insep- arability such as query inseparability and concept inseparability, which generalize corresponding notions of conservative extensions. We survey results on various notions of inseparability in the context of descrip- tion logic ontologies, discussing their applications, useful model-theoretic characterizations, algorithms for determining whether two ontologies are inseparable (and, sometimes, for computing the difference between them if they are not), and the computational complexity of this problem. 1 Introduction Description logic (DL) ontologies provide a common vocabulary for a domain of interest together with a formal modeling of the semantics of the vocabulary items (concept names and role names). -
The Strength of Mac Lane Set Theory
The Strength of Mac Lane Set Theory A. R. D. MATHIAS D´epartement de Math´ematiques et Informatique Universit´e de la R´eunion To Saunders Mac Lane on his ninetieth birthday Abstract AUNDERS MAC LANE has drawn attention many times, particularly in his book Mathematics: Form and S Function, to the system ZBQC of set theory of which the axioms are Extensionality, Null Set, Pairing, Union, Infinity, Power Set, Restricted Separation, Foundation, and Choice, to which system, afforced by the principle, TCo, of Transitive Containment, we shall refer as MAC. His system is naturally related to systems derived from topos-theoretic notions concerning the category of sets, and is, as Mac Lane emphasizes, one that is adequate for much of mathematics. In this paper we show that the consistency strength of Mac Lane's system is not increased by adding the axioms of Kripke{Platek set theory and even the Axiom of Constructibility to Mac Lane's axioms; our method requires a close study of Axiom H, which was proposed by Mitchell; we digress to apply these methods to subsystems of Zermelo set theory Z, and obtain an apparently new proof that Z is not finitely axiomatisable; we study Friedman's strengthening KPP + AC of KP + MAC, and the Forster{Kaye subsystem KF of MAC, and use forcing over ill-founded models and forcing to establish independence results concerning MAC and KPP ; we show, again using ill-founded models, that KPP + V = L proves the consistency of KPP ; turning to systems that are type-theoretic in spirit or in fact, we show by arguments of Coret -
Student Financial Services Payment and Financial Aid Policies
Student Financial Services Payment and Financial Aid Policies Last Updated on 08.06.2015 Student Financial Services 2015-06-08 page 1 of 1 TABLE OF CONTENTS 1. INTRODUCTION ...................................................................................................................................................... 3 2. STUDENT ACCOUNT PAYMENT POLICIES ................................................................................................................ 3 2.1 Undergraduate Student Charges .................................................................................................................. 3 2.2 Undergraduate Financial Aid Packages ........................................................................................................ 4 2.3 Graduate Student Charges ............................................................................................................................ 5 2.4 Withdrawal Policy - Undergraduate Students ............................................................................................... 6 2.5 Refund Policy – Undergraduate Students .................................................................................................... 6 2.6 Withdrawal and Refund Policy for Non-degree Students ............................................................................. 6 2.7 Graduating from Jacobs University ............................................................................................................... 7 3. UNDERGRADUATE FINANCIAL AID POLICIES ..........................................................................................................