An Adaptive Time-Stepping Algorithm for the Allen–Cahn Equation

<div>Temporal evolution with the initial states (16): (a) zero level contour of <svg height="12.7178pt" id="M189" style="vertical-align:-3.42947pt" version="1.1" viewbox="-0.0498162 -9.28833 46.1094 12.7178" width="46.1094pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M542 242C542 369 469 429 379 468C370 472 372 496 376 513L416 681L400 691L344 648L219 51C167 69 113 128 113 217C113 324 166 387 266 428L252 459C124 418 23 336 23 202C23 95 90 13 205 -8L182 -132C165 -222 191 -254 209 -261L215 -258L270 -7C415 -4 542 98 542 242ZM469 232C469 126 403 33 279 39L355 409C399 394 469 331 469 232Z"></path></g><g transform="matrix(.013,0,0,-0.013,7.346,0)"><path d="M300 -147C201 -63 143 98 143 270S200 602 300 686L282 710C136 610 70 450 70 271V270C70 89 136 -72 282 -170L300 -147Z"></path></g><g transform="matrix(.013,0,0,-0.013,11.844,0)"><path d="M536 404C536 423 520 448 491 448C445 448 398 404 308 283L286 338C255 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the discrete total energy <span class="nowrap"><svg height="12.5794pt" id="M193" style="vertical-align:-3.29107pt" version="1.1" viewbox="-0.0498162 -9.28833 28.6774 12.5794" width="28.6774pt" xmlns="http://www.w3.org/2000/svg" xmlns:xlink="http://www.w3.org/1999/xlink"><g transform="matrix(.013,0,0,-0.013,0,0)"><path d="M421 658C372 683 338 687 289 687C174 687 100 624 100 549C100 458 196 404 336 401C341 401 342 386 347 381V379C196 347 110 258 110 154C110 43 211 -15 326 -15C463 -15 584 71 584 161C584 228 542 276 450 276C352 276 275 206 248 98L269 92C293 177 364 234 433 234C485 234 520 207 520 160C520 131 509 102 485 75C454 40 404 15 336 15C244 15 192 73 192 134C192 220 267 311 387 343C403 334 419 329 440 329C464 329 482 338 482 357C482 377 454 385 407 388C404 392 404 393 403 400C588 413 734 506 734 585C734 633 698 658 634 658C511 658 343 568 332 432C229 432 141 472 141 546C141 610 204 657 301 657C356 657 372 656 411 640L421 658ZM693 588C693 524 566 441 403 430C416 521 546 621 641 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Journal of Function Spaces

An Adaptive Time-Stepping Algorithm for the Allen–Cahn Equation

Figure 7