233,170 research outputs found
James C. Furman to Reverend A.D. Cohen
No full textA three page letter from James C. Furman to Reverend A.D. Cohen
On the local-indicability cohen–lyndon theorem
No full textFor a group H and a subset X of H, we let HX denote the set {hxh?1 | h ? H, x ? X}, and when X is a free-generating set of H, we say that the set HX is a Whitehead subset of H. For a group F and an element r of F, we say that r is Cohen–Lyndon aspherical in F if F{r} is a Whitehead subset of the subgroup of F that is generated by F{r}. In 1963, Cohen and Lyndon (D. E. Cohen and R. C. Lyndon, Free bases for normal subgroups of free groups, Trans. Amer. Math. Soc. 108 (1963), 526–537) independently showed that in each free group each non-trivial element is Cohen–Lyndon aspherical. Their proof used the celebrated induction method devised by Magnus in 1930 to study one-relator groups. In 1987, Edjvet and Howie (M. Edjvet and J. Howie, A Cohen–Lyndon theorem for free products of locally indicable groups, J. Pure Appl. Algebra 45 (1987), 41–44) showed that if A and B are locally indicable groups, then each cyclically reduced element of A*B that does not lie in A ? B is Cohen–Lyndon aspherical in A*B. Their proof used the original Cohen–Lyndon theorem. Using Bass–Serre theory, the original Cohen–Lyndon theorem and the Edjvet–Howie theorem, one can deduce the local-indicability Cohen–Lyndon theorem: if F is a locally indicable group and T is an F-tree with trivial edge stabilisers, then each element of F that fixes no vertex of T is Cohen–Lyndon aspherical in F. Conversely, by Bass–Serre theory, the original Cohen–Lyndon theorem and the Edjvet–Howie theorem are immediate consequences of the local-indicability Cohen–Lyndon theorem. In this paper we give a detailed review of a Bass–Serre theoretical form of Howie induction and arrange the arguments of Edjvet and Howie into a Howie-inductive proof of the local-indicability Cohen–Lyndon theorem that uses neither Magnus induction nor the original Cohen–Lyndon theorem. We conclude with a review of some standard applications of Cohen–Lyndon asphericit
Oral history interview with Arnold A. Cohen
No full textTranscript, 48 pp. Audio file available at http://purl.umn.edu/95550The interview focuses on Engineering Research Associates (ERA). Cohen begins the interview by briefly describing most of the early ERA personnel. He discusses his own work and that of C. B. Tompkins on various ERA projects including the Goldberg Project and the design of memory systems.Cohen, Arnold A.. (1987). Oral history interview with Arnold A. Cohen. Retrieved from the University Digital Conservancy, https://hdl.handle.net/11299/107221
Humanics: Creed vs. Deed - Joel R. Cohen (c. 1991)
No full textThis document titled “Humanics: Creed vs. Deed” is the Humanics Lecture that was given at Springfield College by Distinguished Professor of Humanics Joel R. Cohen on April 24, 1991.
Upon being appointed Distinguished Professor of Humanics at Springfield College, Cohen, part-time archivist and historian, admits that at first his response was “let me think about it.” Cohen decided to accept the honor, only after convincing the Dean to go back to the original tradition of presenting the lecture at the end of the spring semester rather than at the beginning of the fall semester. Cohen looks back on the history of Humanics and what previous speakers have said. He points out that Humanics has been defined from two different perspectives: it has been characterized as a philosophy by some (Doggett, Arenian, Congdon), and as a way of life by others (Holmes, VanDerbeck, Paar, Ross). Cohen references Robertson’s 1988 Humanics Lecture, “Connections,” and discusses four examples deficiencies in our Humanics philosophy and why our connections have become dimmed.
First is volunteerism. Cohen describes a memo he distributed during the fall term of 1989 requesting Alzheimer’s Disease Respite Volunteers. The memo was run for four consecutive weeks in the Springfield Student as well as six weeks in Communications. Cohen received three calls from students, in which one followed through with a visit to his office, but after that, no one contacted Baystate Medical Center. There were no responses from faculty, administration, or staff. Cohen suggested the need to make volunteerism a part of the All-College Requirements. The next example has to do with internal relations. Cohen discusses a draft published in May 1988 to address this topic by developing a system of governance that is consistent with the Humanics Philosophy. This will be done through restructuring and consolidation of personnel groups to strengthen a sense of community. Commitment to the local community is the next topic, in which Cohen discusses expanding external relations to improve the quality of life in the local community by developing a public relations program to educate students to serve others. Last is commitment to minority students and/ or cultural diversity. Cohen states the College’s current plan to have a minority population of approximately 10% enrollment by 1992. On February 25, 1991 he reported that the college only had 5.26% of minorities making up the student body, a far cry from the 10% goal. Cohen concludes by stating that these deficiencies should not contribute to making Humanics a deed, rather Humanics should be a creed.Humanics is a word that has a special meaning in the history and philosophy of Springfield College, as well as in the college’s motto of “Spirit, Mind, and Body.” The Oxford English Dictionary defines Humanics as, “the subject or study of human affairs or relations, especially of the human element of a problem or situation as opposed to the mechanical.” In 1962, Dr. Glenn Olds, President of Springfield College at the time, began to wonder why this name was given to the intended philosophy of the college by Dr. Laurence Locke Doggett, Springfield College’s first full-time president. Olds acknowledged that the practices of the faculty were in large part consistent with the Humanics philosophy, but he believed that a more self-conscious application would improve chances of its continuity and survival. To ensure this, a Distinguished Professor of Humanics position was created at the college, first filled by Dr. Seth Arsenian from 1966-1969. The purpose of this position was to catalyze a renewal of consciousness in the philosophy. This was done by annually mandating the Distinguished Professor of Humanics to give a Humanics lecture on the definition of Humanics and what the concept means to them. Arsenian started this tradition in 1967 with his speech titled, “The Meaning of Humanics,” in which he described the concept as a set of ideas, values, and goals that make our college distinct from other colleges and make commitment and unity toward commonly sought goals possible
The cohomology of the braid group and of with coefficients in a geometric representation
No full textThis article is a short version of a paper which addresses the cohomology of the third braid group and of with coefficients in geometric representations.We give precise statements of the results, some tools and some proofs, avoiding very technical computations here
C. Cohen, Le destin du mamouth
No full textDuvernay-Bolens Jacqueline. C. Cohen, Le destin du mamouth. In: L'Homme, 1997, tome 37 n°141. pp. 161-162
C. Cohen, Le destin du mamouth
No full textDuvernay-Bolens Jacqueline. C. Cohen, Le destin du mamouth. In: L'Homme, 1997, tome 37 n°141. pp. 161-162
Business Papers (MS 80-0003)
No full textHandwritten letter from C. E. Smith to Sass & Cohen discussing how debts will get paid
Is the discount on the secondary market a case for LDC debt relief?
No full textIn 1988, the prices on the secondary market of LDC debt averaged 50 cents per dollar of face value. From the observation of such discount, this paper goes one step further and argues thatthe debt should be written down in order to account for the discrepancy between the face and market value of the debt. The paper is structured as follows. Section 1 spells out the model, section 2 calculates the socially efficient and the post-default growth rates of the economy. Section 3 shows that the lenders, if they were to monitor the investment and the consumption strategy of the borrower, would choose a lower investment strategy than the socially efficient one. Section 4 shows how an optimum rescheduling can achieve the equilibrium described in section 3. Section 5 shows the dynamic inconsistency of the optimal strategy spelled out in section 4, and shows the link with the"debt overhang"literature. Section 6 investigates the empirical relevance of the"debt overhang".Economic Theory&Research,Banks&Banking Reform,Environmental Economics&Policies,Strategic Debt Management,Financial Intermediation
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