Knowledge

Lars Svenonius

Source 📝

142:(The Theory of Models, North-Holland Publishing Co., 1965) as "On the denumerable models of theories with extra predicates", pp 376–389. In this paper he characterizes the countable ("denumerable") structures which can be made into models of a theory by adding interpretations of the extra predicates used in defining the theory. His characterization involves (infinite) expressions beginning with an infinite sequence of alternating quantifiers. Such expressions are now interpreted using infinite two-person games. The importance of this work was only realized after it was rediscovered and extended by Robert Vaught in his work on 123:
first-order theory is invariant under permutations ("automorphisms") of the model fixing the other predicates, then the interpretation of that predicate is definable in every model by a formula involving only the other predicates; furthermore only finitely many such defining formulas are required. Beth's earlier
122:
In particular, paper (2) contains what is now called "Svenonius' Theorem", an important result on definability of predicates in first order theories. Even the statement of this result requires mathematical model-theoretic concepts. It states that if the interpretation of a predicate in any model of a
141:
Presumably as a result of these papers he was named a visiting associate professor at The University of California, Berkeley, for 1962–1963, and gave an Invited Address at the International Symposium on the Theory of Models held there in 1963. His address was published in the Conference Proceedings
73:
Lars Svenonius' early work was in the field of logic known as model theory, in which properties of the interpretations ("models") of theories are studied. This field was the object of intense study and saw great progress in the 1950s, largely due to the work of
56:(for which the University of Uppsala awarded him a doctorate in 1960). His early work was in formal logic, and he established a reputation for brilliance early in his career with a series of proofs, including an independent proof of 78:
and his students at the University of California, Berkeley. At the same time it became much more mathematical, both in techniques and in the concepts used. Svenonius' work was of the modern mathematical variety.
41:
He was a visiting professor at University of California at Berkeley in 1962–63, then held a position at the University of Chicago from 1963 to 1969, and was professor of philosophy at the
45:
from 1969 to 2009. He retired in 2009, but was awarded the position of emeritus professor, and continued to teach courses and advise students until his death at 83 years of age.
110: 234: 194: 82:
Svenonius' reputation as a mathematical model theorist was established with the publication of three papers in Theoria in 1959 and 1960:
154:
who defines "Svenonius games" and "Svenonius sentences" in his encyclopedic treatise Model Theory (Cambridge University Press, 1993).
178: 130:
The other two papers include a characterization of theories having only one countable model, obtained also by the Polish logician
239: 199: 62: 66:
establishes what is still referred to as the 'Svenonius theorem' on decidability. One of his proponents in Sweden was
219: 131: 204: 57: 27: 143: 42: 229: 224: 88: 174: 124: 147: 67: 151: 213: 135: 75: 23: 200:
Washington Post: Lars Svenonius, 83, emeritus professor of philosophy at U-Md., dies
49: 35: 31: 138:
at Berkeley. All of these results are classics of modern model theory.
58:
equivalent characterizations of omega-categorical theories
150:. Svenonius' role is well recognized, for example, by 91: 104: 134:, and results on prime models, obtained also by 112:-categoricity in first-order predicate calculus, 48:He was the first Swedish logician to work on 8: 118:On minimal models of first-order systems. 96: 90: 127:is a consequence of Svenonius' Theorem. 163: 7: 115:A theorem on permutations in models, 235:People from Skellefteå Municipality 93: 14: 16:Swedish logician and philosopher 195:University of Maryland Faculty 1: 205:Lars S. E. Svenonius obituary 54:Some problems in Model Theory 171:Handbook of world philosophy 105:{\displaystyle \aleph _{0}} 256: 60:. A 1959 paper of his in 173:by John Roy Burr, 1980. 132:Czesław Ryll-Nardzewski 28:Silver Spring, Maryland 144:descriptive set theory 106: 52:with his dissertation 43:University of Maryland 26:– September 27, 2010, 107: 240:Swedish philosophers 125:definability theorem 89: 102: 220:Swedish logicians 148:infinitary logics 247: 182: 168: 111: 109: 108: 103: 101: 100: 30:) was a Swedish 22:(June 16, 1927, 255: 254: 250: 249: 248: 246: 245: 244: 210: 209: 191: 186: 185: 169: 165: 160: 92: 87: 86: 17: 12: 11: 5: 253: 251: 243: 242: 237: 232: 227: 222: 212: 211: 208: 207: 202: 197: 190: 189:External links 187: 184: 183: 162: 161: 159: 156: 152:Wilfrid Hodges 120: 119: 116: 113: 99: 95: 20:Lars Svenonius 15: 13: 10: 9: 6: 4: 3: 2: 252: 241: 238: 236: 233: 231: 228: 226: 223: 221: 218: 217: 215: 206: 203: 201: 198: 196: 193: 192: 188: 180: 179:0-313-22381-5 176: 172: 167: 164: 157: 155: 153: 149: 145: 139: 137: 136:Robert Vaught 133: 128: 126: 117: 114: 97: 85: 84: 83: 80: 77: 76:Alfred Tarski 71: 69: 68:Per Lindström 65: 64: 59: 55: 51: 46: 44: 39: 37: 33: 29: 25: 21: 170: 166: 140: 129: 121: 81: 72: 61: 53: 50:model theory 47: 40: 19: 18: 230:2010 deaths 225:1927 births 36:philosopher 214:Categories 181:(page 186) 158:References 24:Skellefteå 94:ℵ 32:logician 63:Theoria 177:  175:ISBN 146:and 34:and 70:. 38:. 216:: 98:0

Index

Skellefteå
Silver Spring, Maryland
logician
philosopher
University of Maryland
model theory
equivalent characterizations of omega-categorical theories
Theoria
Per Lindström
Alfred Tarski
definability theorem
Czesław Ryll-Nardzewski
Robert Vaught
descriptive set theory
infinitary logics
Wilfrid Hodges
ISBN
0-313-22381-5
University of Maryland Faculty
Washington Post: Lars Svenonius, 83, emeritus professor of philosophy at U-Md., dies
Lars S. E. Svenonius obituary
Categories
Swedish logicians
1927 births
2010 deaths
People from Skellefteå Municipality
Swedish philosophers

Text is available under the Creative Commons Attribution-ShareAlike License. Additional terms may apply.