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Bour's minimal surface

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Bour's surface crosses itself on three coplanar rays, meeting at equal angles at the origin of the space. The rays partition the surface into six sheets, topologically equivalent to half-planes; three sheets lie in the halfspace above the plane of the rays, and three below. Four of the sheets are
365:{\displaystyle {\begin{aligned}x(r,\theta )&=r\cos(\theta )-{\tfrac {1}{2}}r^{2}\cos(2\theta )\\y(r,\theta )&=-r\sin(\theta )(r\cos(\theta )+1)\\z(r,\theta )&={\tfrac {4}{3}}r^{3/2}\cos \left({\tfrac {3}{2}}\theta \right).\end{aligned}}} 96: 450: 545: 385: 487: 658: 538: 585: 638: 575: 590: 688: 531: 492: 395: 668: 653: 457: 52:, whose work on minimal surfaces won him the 1861 mathematics prize of the French Academy of Sciences. 373: 478: 453: 86: 517:
Ulrich Dierkes, Stefan Hildebrandt, Friedrich Sauvigny, Minimal Surfaces, Volume 1. Springer 2010
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The surface can also be expressed as the solution to a polynomial equation of order 16 in the
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Weisstein, Eric W. "Bour's Minimal Surface." From MathWorld--A Wolfram Web Resource.
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into minimal surfaces, produces this surface for the two functions
23: 15: 527: 32: < 0.5 to show the self-crossings more clearly. 388:, a method for turning certain pairs of functions over the 452:. It was proved by Bour that surfaces in this family are 44:, embedded with self-crossings into three-dimensional 336: 295: 146: 507:
http://mathworld.wolfram.com/BoursMinimalSurface.html
398: 94: 444: 364: 69:The points on the surface may be parameterized in 539: 8: 28:Bour's surface, leaving out the points with 546: 532: 524: 435: 397: 335: 314: 310: 294: 161: 145: 95: 93: 488:MacTutor History of Mathematics Archive 469: 445:{\displaystyle f(z)=1,g(z)={\sqrt {z}}} 7: 386:Weierstrass–Enneper parameterization 14: 61:mutually tangent along each ray. 667: 376:of the three-dimensional space. 429: 423: 408: 402: 284: 272: 262: 253: 247: 235: 232: 226: 204: 192: 182: 173: 139: 133: 114: 102: 1: 705: 665: 561: 493:University of St Andrews 446: 366: 38:Bour's minimal surface 33: 21: 458:surface of revolution 447: 374:Cartesian coordinates 367: 73:by a pair of numbers 40:is a two-dimensional 27: 19: 479:Robertson, Edmund F. 396: 92: 87:parametric equations 48:. It is named after 477:O'Connor, John J.; 442: 362: 360: 345: 304: 155: 34: 22: 676: 675: 440: 344: 303: 154: 71:polar coordinates 696: 689:Minimal surfaces 671: 586:Chen–Gackstatter 566:Associate family 555:Minimal surfaces 548: 541: 534: 525: 518: 515: 509: 503: 497: 495: 474: 451: 449: 448: 443: 441: 436: 371: 369: 368: 363: 361: 354: 350: 346: 337: 323: 322: 318: 305: 296: 166: 165: 156: 147: 84: 36:In mathematics, 704: 703: 699: 698: 697: 695: 694: 693: 679: 678: 677: 672: 663: 659:Triply periodic 557: 552: 522: 521: 516: 512: 504: 500: 476: 475: 471: 466: 394: 393: 390:complex numbers 382: 359: 358: 334: 330: 306: 287: 266: 265: 207: 186: 185: 157: 117: 90: 89: 74: 67: 58: 46:Euclidean space 42:minimal surface 20:Bour's surface. 12: 11: 5: 702: 700: 692: 691: 681: 680: 674: 673: 666: 664: 662: 661: 656: 651: 646: 641: 636: 631: 626: 621: 613: 608: 603: 598: 593: 588: 583: 578: 573: 568: 562: 559: 558: 553: 551: 550: 543: 536: 528: 520: 519: 510: 498: 468: 467: 465: 462: 439: 434: 431: 428: 425: 422: 419: 416: 413: 410: 407: 404: 401: 381: 378: 357: 353: 349: 343: 340: 333: 329: 326: 321: 317: 313: 309: 302: 299: 293: 290: 288: 286: 283: 280: 277: 274: 271: 268: 267: 264: 261: 258: 255: 252: 249: 246: 243: 240: 237: 234: 231: 228: 225: 222: 219: 216: 213: 210: 208: 206: 203: 200: 197: 194: 191: 188: 187: 184: 181: 178: 175: 172: 169: 164: 160: 153: 150: 144: 141: 138: 135: 132: 129: 126: 123: 120: 118: 116: 113: 110: 107: 104: 101: 98: 97: 66: 63: 57: 54: 13: 10: 9: 6: 4: 3: 2: 701: 690: 687: 686: 684: 670: 660: 657: 655: 652: 650: 647: 645: 642: 640: 637: 635: 632: 630: 627: 625: 622: 620: 618: 614: 612: 609: 607: 604: 602: 599: 597: 594: 592: 589: 587: 584: 582: 579: 577: 574: 572: 569: 567: 564: 563: 560: 556: 549: 544: 542: 537: 535: 530: 529: 526: 514: 511: 508: 502: 499: 494: 490: 489: 484: 483:"Edmond Bour" 480: 473: 470: 463: 461: 459: 455: 437: 432: 426: 420: 417: 414: 411: 405: 399: 391: 387: 379: 377: 375: 355: 351: 347: 341: 338: 331: 327: 324: 319: 315: 311: 307: 300: 297: 291: 289: 281: 278: 275: 269: 259: 256: 250: 244: 241: 238: 229: 223: 220: 217: 214: 211: 209: 201: 198: 195: 189: 179: 176: 170: 167: 162: 158: 151: 148: 142: 136: 130: 127: 124: 121: 119: 111: 108: 105: 99: 88: 82: 78: 72: 64: 62: 55: 53: 51: 47: 43: 39: 31: 26: 18: 644:Saddle tower 616: 570: 513: 501: 486: 472: 383: 80: 76: 68: 59: 37: 35: 29: 454:developable 56:Description 50:Edmond Bour 464:References 380:Properties 639:Riemann's 611:Henneberg 576:Catalan's 348:θ 328:⁡ 282:θ 251:θ 245:⁡ 230:θ 224:⁡ 215:− 202:θ 180:θ 171:⁡ 143:− 137:θ 131:⁡ 112:θ 683:Category 634:Richmond 624:Lidinoid 606:Helicoid 581:Catenoid 65:Equation 654:Schwarz 629:Neovius 596:Enneper 591:Costa's 456:onto a 649:Scherk 601:Gyroid 571:Bour's 619:-noid 384:The 325:cos 242:cos 221:sin 168:cos 128:cos 685:: 491:, 485:, 481:, 460:. 79:, 617:k 547:e 540:t 533:v 496:. 438:z 433:= 430:) 427:z 424:( 421:g 418:, 415:1 412:= 409:) 406:z 403:( 400:f 356:. 352:) 342:2 339:3 332:( 320:2 316:/ 312:3 308:r 301:3 298:4 292:= 285:) 279:, 276:r 273:( 270:z 263:) 260:1 257:+ 254:) 248:( 239:r 236:( 233:) 227:( 218:r 212:= 205:) 199:, 196:r 193:( 190:y 183:) 177:2 174:( 163:2 159:r 152:2 149:1 140:) 134:( 125:r 122:= 115:) 109:, 106:r 103:( 100:x 83:) 81:θ 77:r 75:( 30:r

Index



minimal surface
Euclidean space
Edmond Bour
polar coordinates
parametric equations
Cartesian coordinates
Weierstrass–Enneper parameterization
complex numbers
developable
surface of revolution
Robertson, Edmund F.
"Edmond Bour"
MacTutor History of Mathematics Archive
University of St Andrews
http://mathworld.wolfram.com/BoursMinimalSurface.html
v
t
e
Minimal surfaces
Associate family
Bour's
Catalan's
Catenoid
Chen–Gackstatter
Costa's
Enneper
Gyroid
Helicoid

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