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Unfoldable cardinal

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406: 187:. Many theorems related to these cardinals have generalizations to their unfoldable or strongly unfoldable counterparts. For example, the existence of a strongly unfoldable implies the consistency of a slightly weaker version of the 199:
Assuming V = L, the least unfoldable cardinal is greater than the least indescribable cardinal. Assuming a Ramsey cardinal exists, it is less than the least Ramsey cardinal.
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In L, any unfoldable cardinal is strongly unfoldable; thus unfoldable and strongly unfoldable have the same
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is unfoldable and will be strongly unfoldable in L. It may fail to be strongly unfoldable in V, however.
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Villaveces, Andres (1996). "Chains of End Elementary Extensions of Models of Set Theory".
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Johnstone, Thomas A. (2008). "Strongly unfoldable cardinals made indestructible".
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A cardinal k is κ-strongly unfoldable, and κ-unfoldable, if and only if it is
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contains all its sequences of length less than κ, there is a non-trivial
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contains all its sequences of length less than κ, there is a non-trivial
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and preceded by a stationary set of totally indescribable cardinals.
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if and only if it is strongly λ-unfoldable for all λ.
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These properties are essentially weaker versions of
374: 372: 441: 92:if and only if it is an λ-unfoldable for all 8: 238:(2001). "Unfoldable cardinals and the GCH". 195:Relations between large cardinal properties 448: 434: 384: 335: 253: 165:contains all its sequences of length λ. 368: 141:into a transitive model "N" with the 7: 402: 400: 14: 153:(κ) ≥ λ, and V(λ) is a subset of 73:into a transitive model with the 404: 324:Annals of Pure and Applied Logic 220:. A κ+ω-unfoldable cardinal is 1: 241:The Journal of Symbolic Logic 420:. You can help Knowledge by 183:cardinals, consistent with 488: 399: 346:10.1016/j.apal.2006.05.001 161:, we can demand also that 159:Without loss of generality 290:Journal of Symbolic Logic 107:if and only if for every 39:if and only if for every 168:Likewise, a cardinal is 416:-related article is a 303:10.2178/jsl/1230396915 105:strongly λ-unfoldable 24:is a certain kind of 211:consistency strength 189:proper forcing axiom 132:elementary embedding 114:of cardinality κ of 64:elementary embedding 46:of cardinality κ of 320:Hamkins, Joel David 236:Hamkins, Joel David 170:strongly unfoldable 22:unfoldable cardinal 122:such that κ is in 54:such that κ is in 429: 428: 318:Džamonja, Mirna; 479: 472:Set theory stubs 450: 443: 436: 408: 401: 391: 390: 388: 376: 357: 339: 314: 297:(4): 1215–1248. 283: 257: 248:(3): 1186–1198. 109:transitive model 41:transitive model 487: 486: 482: 481: 480: 478: 477: 476: 467:Large cardinals 457: 456: 455: 454: 397: 395: 394: 378: 377: 370: 365: 360: 317: 286: 264:10.2307/2695100 234: 230: 204:Ramsey cardinal 197: 101:cardinal number 33:cardinal number 12: 11: 5: 485: 483: 475: 474: 469: 459: 458: 453: 452: 445: 438: 430: 427: 426: 409: 393: 392: 367: 366: 364: 361: 359: 358: 330:(1–3): 83–95. 315: 284: 231: 229: 226: 218:weakly compact 196: 193: 143:critical point 88:A cardinal is 75:critical point 26:large cardinal 13: 10: 9: 6: 4: 3: 2: 484: 473: 470: 468: 465: 464: 462: 451: 446: 444: 439: 437: 432: 431: 425: 423: 419: 415: 410: 407: 403: 398: 387: 382: 375: 373: 369: 362: 355: 351: 347: 343: 338: 333: 329: 325: 321: 316: 312: 308: 304: 300: 296: 292: 291: 285: 281: 277: 273: 269: 265: 261: 256: 251: 247: 243: 242: 237: 233: 232: 227: 225: 223: 222:indescribable 219: 214: 212: 207: 205: 200: 194: 192: 190: 186: 182: 178: 173: 171: 166: 164: 160: 156: 152: 148: 144: 140: 136: 133: 129: 125: 121: 117: 113: 110: 106: 102: 97: 95: 91: 86: 84: 80: 76: 72: 68: 65: 61: 57: 53: 49: 45: 42: 38: 34: 29: 27: 23: 19: 422:expanding it 411: 396: 386:math/9611209 337:math/0409304 327: 323: 294: 288: 255:math/9909029 245: 239: 215: 208: 201: 198: 181:supercompact 174: 169: 167: 162: 154: 150: 146: 138: 134: 127: 123: 111: 104: 98: 89: 87: 82: 81:being κ and 78: 70: 66: 59: 55: 43: 37:λ-unfoldable 36: 31:Formally, a 30: 21: 15: 18:mathematics 461:Categories 414:set theory 228:References 90:unfoldable 363:Citations 149:being κ, 120:power set 85:(κ) ≥ λ. 52:power set 311:30534686 94:ordinals 28:number. 354:2279655 280:6269487 272:2695100 118:-minus- 50:-minus- 352:  309:  278:  270:  177:strong 412:This 381:arXiv 332:arXiv 307:S2CID 276:S2CID 268:JSTOR 250:arXiv 185:V = L 103:κ is 35:κ is 20:, an 418:stub 179:and 126:and 58:and 342:doi 328:144 299:doi 260:doi 145:of 137:of 116:ZFC 96:λ. 77:of 69:of 48:ZFC 16:In 463:: 371:^ 350:MR 348:. 340:. 326:. 305:. 295:73 293:. 274:. 266:. 258:. 246:66 244:. 213:. 202:A 191:. 157:. 99:A 449:e 442:t 435:v 424:. 389:. 383:: 356:. 344:: 334:: 313:. 301:: 282:. 262:: 252:: 163:N 155:N 151:j 147:j 139:M 135:j 128:M 124:M 112:M 83:j 79:j 71:M 67:j 60:M 56:M 44:M

Index

mathematics
large cardinal
cardinal number
transitive model
ZFC
power set
elementary embedding
critical point
ordinals
cardinal number
transitive model
ZFC
power set
elementary embedding
critical point
Without loss of generality
strong
supercompact
V = L
proper forcing axiom
Ramsey cardinal
consistency strength
weakly compact
indescribable
Hamkins, Joel David
The Journal of Symbolic Logic
arXiv
math/9909029
doi
10.2307/2695100

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