Hide keyboard shortcuts

Hot-keys on this page

r m x p   toggle line displays

j k   next/prev highlighted chunk

0   (zero) top of page

1   (one) first highlighted chunk

1

2

3

4

5

6

7

8

9

10

11

12

13

14

15

16

17

18

19

20

21

22

23

24

25

26

27

28

29

30

31

32

33

34

35

36

37

38

39

40

41

42

43

44

45

46

47

48

49

50

51

52

53

54

55

56

57

58

59

60

61

62

63

64

65

66

67

68

69

70

71

72

73

74

75

76

77

78

79

80

81

82

83

84

85

86

87

88

89

90

91

92

93

94

95

96

97

98

99

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

176

177

178

179

180

181

182

183

184

185

186

187

188

189

190

191

192

193

194

195

196

197

198

199

200

201

202

203

204

205

206

207

208

209

210

211

212

213

214

215

216

217

218

219

220

221

222

223

224

225

226

227

228

229

230

231

232

233

234

235

236

237

238

239

240

241

242

243

244

245

246

247

248

249

250

251

252

253

254

255

256

257

258

259

260

261

262

263

264

265

266

267

268

269

270

271

272

273

274

275

276

277

278

279

280

281

282

283

284

285

286

287

288

289

290

291

292

293

294

295

296

297

298

299

300

301

302

303

304

305

306

307

308

309

310

311

312

313

314

315

316

317

318

319

320

321

322

323

324

325

326

327

328

329

330

331

332

333

334

335

336

337

338

339

340

341

342

343

344

345

346

347

348

349

350

351

352

353

354

355

356

357

358

359

360

361

362

363

364

365

366

367

368

369

370

371

372

373

374

375

376

377

378

379

380

381

382

383

384

385

386

387

388

389

390

391

392

393

394

395

396

397

398

399

400

401

402

403

404

405

406

407

408

409

410

411

412

413

414

415

416

417

418

419

420

421

422

423

424

425

426

427

428

429

430

431

432

433

434

435

436

437

438

439

440

441

442

443

444

445

446

447

448

449

450

451

452

453

454

455

456

457

458

459

460

461

462

463

464

465

466

467

468

469

470

471

472

473

474

475

476

477

478

479

480

481

482

483

484

485

486

487

488

489

490

491

492

493

494

495

496

497

498

499

500

501

502

503

504

505

506

507

508

509

510

511

512

513

514

515

516

517

518

519

520

521

522

523

524

525

526

527

528

529

530

531

532

533

534

535

536

r""" 

Rigged Configurations of `\mathcal{B}(\infty)` 

 

AUTHORS: 

 

- Travis Scrimshaw (2013-04-16): Initial version 

""" 

 

#***************************************************************************** 

# Copyright (C) 2013 Travis Scrimshaw <tscrim@ucdavis.edu> 

# 

# Distributed under the terms of the GNU General Public License (GPL) 

# 

# This code is distributed in the hope that it will be useful, 

# but WITHOUT ANY WARRANTY; without even the implied warranty of 

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU 

# General Public License for more details. 

# 

# The full text of the GPL is available at: 

# 

# http://www.gnu.org/licenses/ 

#***************************************************************************** 

 

from sage.misc.lazy_attribute import lazy_attribute 

from sage.structure.unique_representation import UniqueRepresentation 

from sage.structure.parent import Parent 

from sage.categories.highest_weight_crystals import HighestWeightCrystals 

from sage.categories.homset import Hom 

from sage.combinat.root_system.cartan_type import CartanType 

from sage.combinat.rigged_configurations.rigged_configuration_element import ( 

RiggedConfigurationElement, RCNonSimplyLacedElement) 

from sage.combinat.rigged_configurations.rigged_configurations import RiggedConfigurations 

from sage.combinat.rigged_configurations.rigged_partition import RiggedPartition 

 

# Note on implementation, this class is used for simply-laced types only 

class InfinityCrystalOfRiggedConfigurations(UniqueRepresentation, Parent): 

r""" 

Rigged configuration model for `\mathcal{B}(\infty)`. 

 

The crystal is generated by the empty rigged configuration with the same 

crystal structure given by the :class:`highest weight model 

<sage.combinat.rigged_configurations.rc_crystal.CrystalOfRiggedConfigurations>` 

except we remove the condition that the resulting rigged configuration 

needs to be valid when applying `f_a`. 

 

INPUT: 

 

- ``cartan_type`` -- a Cartan type 

 

EXAMPLES: 

 

For simplicity, we display all of the rigged configurations 

horizontally:: 

 

sage: RiggedConfigurations.options(display='horizontal') 

 

We begin with a simply-laced finite type:: 

 

sage: RC = crystals.infinity.RiggedConfigurations(['A', 3]); RC 

The infinity crystal of rigged configurations of type ['A', 3] 

 

sage: RC.options(display='horizontal') 

 

sage: mg = RC.highest_weight_vector(); mg 

(/) (/) (/) 

sage: elt = mg.f_string([2,1,3,2]); elt 

0[ ]0 -2[ ]-1 0[ ]0 

-2[ ]-1 

sage: elt.e(1) 

sage: elt.e(3) 

sage: mg.f_string([2,1,3,2]).e(2) 

-1[ ]-1 0[ ]1 -1[ ]-1 

sage: mg.f_string([2,3,2,1,3,2]) 

0[ ]0 -3[ ][ ]-1 -1[ ][ ]-1 

-2[ ]-1 

 

Next we consider a non-simply-laced finite type:: 

 

sage: RC = crystals.infinity.RiggedConfigurations(['C', 3]) 

sage: mg = RC.highest_weight_vector() 

sage: mg.f_string([2,1,3,2]) 

0[ ]0 -1[ ]0 0[ ]0 

-1[ ]-1 

sage: mg.f_string([2,3,2,1,3,2]) 

0[ ]-1 -1[ ][ ]-1 -1[ ][ ]0 

-1[ ]0 

 

We can construct rigged configurations using a diagram folding of 

a simply-laced type. This yields an equivalent but distinct crystal:: 

 

sage: vct = CartanType(['C', 3]).as_folding() 

sage: VRC = crystals.infinity.RiggedConfigurations(vct) 

sage: mg = VRC.highest_weight_vector() 

sage: mg.f_string([2,1,3,2]) 

0[ ]0 -2[ ]-1 0[ ]0 

-2[ ]-1 

sage: mg.f_string([2,3,2,1,3,2]) 

-1[ ]-1 -2[ ][ ][ ]-1 -1[ ][ ]0 

 

sage: G = RC.subcrystal(max_depth=5).digraph() 

sage: VG = VRC.subcrystal(max_depth=5).digraph() 

sage: G.is_isomorphic(VG, edge_labels=True) 

True 

 

We can also construct `B(\infty)` using rigged configurations in 

affine types:: 

 

sage: RC = crystals.infinity.RiggedConfigurations(['A', 3, 1]) 

sage: mg = RC.highest_weight_vector() 

sage: mg.f_string([0,1,2,3,0,1,3]) 

-1[ ]0 -1[ ]-1 1[ ]1 -1[ ][ ]-1 

-1[ ]0 -1[ ]-1 

 

sage: RC = crystals.infinity.RiggedConfigurations(['C', 3, 1]) 

sage: mg = RC.highest_weight_vector() 

sage: mg.f_string([1,2,3,0,1,2,3,3,0]) 

-2[ ][ ]-1 0[ ]1 0[ ]0 -4[ ][ ][ ]-2 

0[ ]0 0[ ]-1 

 

sage: RC = crystals.infinity.RiggedConfigurations(['A', 6, 2]) 

sage: mg = RC.highest_weight_vector() 

sage: mg.f_string([1,2,3,0,1,2,3,3,0]) 

0[ ]-1 0[ ]1 0[ ]0 -4[ ][ ][ ]-2 

0[ ]-1 0[ ]1 0[ ]-1 

 

We reset the global options:: 

 

sage: RiggedConfigurations.options._reset() 

""" 

@staticmethod 

def __classcall_private__(cls, cartan_type): 

r""" 

Normalize the input arguments to ensure unique representation. 

 

EXAMPLES:: 

 

sage: RC1 = crystals.infinity.RiggedConfigurations(CartanType(['A',3])) 

sage: RC2 = crystals.infinity.RiggedConfigurations(['A',3]) 

sage: RC2 is RC1 

True 

""" 

from sage.combinat.root_system.type_folded import CartanTypeFolded 

if isinstance(cartan_type, CartanTypeFolded): 

return InfinityCrystalOfNonSimplyLacedRC(cartan_type) 

 

cartan_type = CartanType(cartan_type) 

return super(InfinityCrystalOfRiggedConfigurations, cls).__classcall__(cls, cartan_type) 

 

def __init__(self, cartan_type): 

r""" 

Initialize ``self``. 

 

EXAMPLES:: 

 

sage: RC = crystals.infinity.RiggedConfigurations(['A', 2]) 

sage: TestSuite(RC).run() 

sage: RC = crystals.infinity.RiggedConfigurations(['A', 2, 1]) 

sage: TestSuite(RC).run() # long time 

sage: RC = crystals.infinity.RiggedConfigurations(['C', 2]) 

sage: TestSuite(RC).run() # long time 

sage: RC = crystals.infinity.RiggedConfigurations(['C', 2, 1]) 

sage: TestSuite(RC).run() # long time 

""" 

self._cartan_type = cartan_type 

Parent.__init__(self, category=HighestWeightCrystals().Infinite()) 

self._rc_index = self._cartan_type.index_set() 

self._rc_index_inverse = {i: ii for ii,i in enumerate(self._rc_index)} 

# We store the Cartan matrix for the vacancy number calculations for speed 

self._cartan_matrix = self._cartan_type.cartan_matrix() 

self.module_generators = (self.element_class(self, rigging_list=[[]]*cartan_type.rank()),) 

 

options = RiggedConfigurations.options 

 

def _repr_(self): 

""" 

Return a string representation of ``self``. 

 

EXAMPLES:: 

 

sage: crystals.infinity.RiggedConfigurations(['A', 3]) 

The infinity crystal of rigged configurations of type ['A', 3] 

""" 

return "The infinity crystal of rigged configurations of type {}".format(self._cartan_type) 

 

def _element_constructor_(self, lst=None, **options): 

""" 

Construct an element of ``self`` from ``lst``. 

 

EXAMPLES:: 

 

sage: RC = crystals.infinity.RiggedConfigurations(['A', 3, 1]) 

sage: ascii_art(RC(partition_list=[[1,1]]*4, rigging_list=[[1,1], [0,0], [0,0], [-1,-1]])) 

0[ ]1 0[ ]0 0[ ]0 0[ ]-1 

0[ ]1 0[ ]0 0[ ]0 0[ ]-1 

 

sage: RC = crystals.infinity.RiggedConfigurations(['C', 3]) 

sage: ascii_art(RC(partition_list=[[1],[1,1],[1]], rigging_list=[[0],[0,-1],[0]])) 

0[ ]0 -1[ ]0 0[ ]0 

-1[ ]-1 

 

TESTS: 

 

Check that :trac:`17054` is fixed:: 

 

sage: RC = RiggedConfigurations(['A',2,1], [[1,1]]*4 + [[2,1]]*4) 

sage: B = crystals.infinity.RiggedConfigurations(['A',2]) 

sage: x = RC().f_string([2,2,1,1,2,1,2,1]) 

sage: ascii_art(x) 

0[ ][ ][ ][ ]-4 0[ ][ ][ ][ ]0 

sage: ascii_art(B(x)) 

-4[ ][ ][ ][ ]-4 -4[ ][ ][ ][ ]0 

sage: x == RC().f_string([2,2,1,1,2,1,2,1]) 

True 

""" 

if isinstance(lst, RiggedConfigurationElement): 

lst = [p._clone() for p in lst] # Make a deep copy 

elif isinstance(lst, list) and bool(lst) and isinstance(lst[0], RiggedPartition): 

lst = [p._clone() for p in lst] # Make a deep copy 

return self.element_class(self, lst, **options) 

 

def _coerce_map_from_(self, P): 

""" 

Return ``True`` or the coerce map from ``P`` if a map exists. 

 

EXAMPLES:: 

 

sage: T = crystals.infinity.Tableaux(['A',3]) 

sage: RC = crystals.infinity.RiggedConfigurations(['A',3]) 

sage: RC._coerce_map_from_(T) 

Crystal Isomorphism morphism: 

From: The infinity crystal of tableaux of type ['A', 3] 

To: The infinity crystal of rigged configurations of type ['A', 3] 

""" 

if self.cartan_type().is_finite(): 

from sage.combinat.crystals.infinity_crystals import InfinityCrystalOfTableaux 

if (isinstance(P, InfinityCrystalOfTableaux) 

and self.cartan_type().is_simply_laced()): 

from sage.combinat.rigged_configurations.bij_infinity import FromTableauIsomorphism 

return FromTableauIsomorphism(Hom(P, self)) 

return super(InfinityCrystalOfRiggedConfigurations, self)._coerce_map_from_(P) 

 

def _calc_vacancy_number(self, partitions, a, i, **options): 

r""" 

Calculate the vacancy number `p_i^{(a)}(\nu)` in ``self``. 

 

This assumes that `\gamma_a = 1` for all `a` and `(\alpha_a \mid 

\alpha_b ) = A_{ab}`. 

 

INPUT: 

 

- ``partitions`` -- the list of rigged partitions we are using 

 

- ``a`` -- the rigged partition index 

 

- ``i`` -- the row length 

 

TESTS:: 

 

sage: RC = crystals.infinity.RiggedConfigurations(['A', 4]) 

sage: elt = RC(partition_list=[[1], [1], [], []]) 

sage: RC._calc_vacancy_number(elt.nu(), 0, 1) 

-1 

""" 

if i == float('inf'): 

return -sum(self._cartan_matrix[a,b] * sum(nu) 

for b,nu in enumerate(partitions)) 

 

return -sum(self._cartan_matrix[a,b] * nu.get_num_cells_to_column(i) 

for b,nu in enumerate(partitions)) 

 

# FIXME: Remove this method!!! 

def weight_lattice_realization(self): 

""" 

Return the weight lattice realization used to express the weights 

of elements in ``self``. 

 

EXAMPLES:: 

 

sage: RC = crystals.infinity.RiggedConfigurations(['A', 2, 1]) 

sage: RC.weight_lattice_realization() 

Extended weight lattice of the Root system of type ['A', 2, 1] 

""" 

R = self._cartan_type.root_system() 

if self._cartan_type.is_affine(): 

return R.weight_lattice(extended=True) 

if self._cartan_type.is_finite() and R.ambient_space(): 

return R.ambient_space() 

return R.weight_lattice() 

 

class Element(RiggedConfigurationElement): 

""" 

A rigged configuration in `\mathcal{B}(\infty)` in simply-laced types. 

 

TESTS:: 

 

sage: RC = crystals.infinity.RiggedConfigurations(['A', 3, 1]) 

sage: elt = RC(partition_list=[[1,1]]*4, rigging_list=[[1,1], [0,0], [0,0], [-1,-1]]) 

sage: TestSuite(elt).run() 

""" 

def weight(self): 

""" 

Return the weight of ``self``. 

 

EXAMPLES:: 

 

sage: RC = crystals.infinity.RiggedConfigurations(['A', 3, 1]) 

sage: elt = RC(partition_list=[[1,1]]*4, rigging_list=[[1,1], [0,0], [0,0], [-1,-1]]) 

sage: elt.weight() 

-2*delta 

""" 

P = self.parent().weight_lattice_realization() 

alpha = list(P.simple_roots()) 

return -sum(sum(x) * alpha[i] for i,x in enumerate(self)) 

 

class InfinityCrystalOfNonSimplyLacedRC(InfinityCrystalOfRiggedConfigurations): 

r""" 

Rigged configurations for `\mathcal{B}(\infty)` in non-simply-laced types. 

""" 

def __init__(self, vct): 

""" 

Initialize ``self``. 

 

EXAMPLES:: 

 

sage: vct = CartanType(['C', 2]).as_folding() 

sage: RC = crystals.infinity.RiggedConfigurations(vct) 

sage: TestSuite(RC).run() # long time 

sage: vct = CartanType(['C', 2, 1]).as_folding() 

sage: RC = crystals.infinity.RiggedConfigurations(vct) 

sage: TestSuite(RC).run() # long time 

""" 

self._folded_ct = vct 

InfinityCrystalOfRiggedConfigurations.__init__(self, vct._cartan_type) 

 

def _coerce_map_from_(self, P): 

""" 

Return ``True`` or the coerce map from ``P`` if a map exists. 

 

EXAMPLES:: 

 

sage: T = crystals.infinity.Tableaux(['C',3]) 

sage: vct = CartanType(['C',3]).as_folding() 

sage: RC = crystals.infinity.RiggedConfigurations(vct) 

sage: RC._coerce_map_from_(T) 

Crystal Isomorphism morphism: 

From: The infinity crystal of tableaux of type ['C', 3] 

To: The infinity crystal of rigged configurations of type ['C', 3] 

""" 

if self.cartan_type().is_finite(): 

from sage.combinat.crystals.infinity_crystals import InfinityCrystalOfTableaux 

if isinstance(P, InfinityCrystalOfTableaux): 

from sage.combinat.rigged_configurations.bij_infinity import FromTableauIsomorphism 

return FromTableauIsomorphism(Hom(P, self)) 

return super(InfinityCrystalOfNonSimplyLacedRC, self)._coerce_map_from_(P) 

 

def _calc_vacancy_number(self, partitions, a, i): 

r""" 

Calculate the vacancy number `p_i^{(a)}(\nu)` in ``self``. 

 

INPUT: 

 

- ``partitions`` -- the list of rigged partitions we are using 

 

- ``a`` -- the rigged partition index 

 

- ``i`` -- the row length 

 

TESTS:: 

 

sage: La = RootSystem(['C', 2]).weight_lattice().fundamental_weights() 

sage: vct = CartanType(['C', 2]).as_folding() 

sage: RC = crystals.RiggedConfigurations(vct, La[1]) 

sage: elt = RC(partition_list=[[1], [1]]) 

sage: RC._calc_vacancy_number(elt.nu(), 0, 1) 

0 

sage: RC._calc_vacancy_number(elt.nu(), 1, 1) 

-1 

""" 

I = self.index_set() 

ia = I[a] 

vac_num = 0 

 

if i == float('inf'): 

return -sum(self._cartan_matrix[a,b] * sum(nu) 

for b,nu in enumerate(partitions)) 

 

gamma = self._folded_ct.scaling_factors() 

g = gamma[ia] 

for b in range(self._cartan_matrix.ncols()): 

ib = I[b] 

q = partitions[b].get_num_cells_to_column(g*i, gamma[ib]) 

vac_num -= self._cartan_matrix[a,b] * q / gamma[ib] 

 

return vac_num 

 

@lazy_attribute 

def virtual(self): 

""" 

Return the corresponding virtual crystal. 

 

EXAMPLES:: 

 

sage: vct = CartanType(['C', 3]).as_folding() 

sage: RC = crystals.infinity.RiggedConfigurations(vct) 

sage: RC 

The infinity crystal of rigged configurations of type ['C', 3] 

sage: RC.virtual 

The infinity crystal of rigged configurations of type ['A', 5] 

""" 

return InfinityCrystalOfRiggedConfigurations(self._folded_ct._folding) 

 

def to_virtual(self, rc): 

""" 

Convert ``rc`` into a rigged configuration in the virtual crystal. 

 

INPUT: 

 

- ``rc`` -- a rigged configuration element 

 

EXAMPLES:: 

 

sage: vct = CartanType(['C', 2]).as_folding() 

sage: RC = crystals.infinity.RiggedConfigurations(vct) 

sage: mg = RC.highest_weight_vector() 

sage: elt = mg.f_string([1,2,2,1,1]); elt 

<BLANKLINE> 

-3[ ][ ][ ]-2 

<BLANKLINE> 

-1[ ][ ]0 

<BLANKLINE> 

sage: velt = RC.to_virtual(elt); velt 

<BLANKLINE> 

-3[ ][ ][ ]-2 

<BLANKLINE> 

-2[ ][ ][ ][ ]0 

<BLANKLINE> 

-3[ ][ ][ ]-2 

<BLANKLINE> 

sage: velt.parent() 

The infinity crystal of rigged configurations of type ['A', 3] 

""" 

gamma = [int(_) for _ in self._folded_ct.scaling_factors()] 

sigma = self._folded_ct._orbit 

n = self._folded_ct._folding.rank() 

vindex = self._folded_ct._folding.index_set() 

partitions = [None] * n 

riggings = [None] * n 

for a, rp in enumerate(rc): 

for i in sigma[a]: 

k = vindex.index(i) 

partitions[k] = [row_len*gamma[a] for row_len in rp._list] 

riggings[k] = [rig_val*gamma[a] for rig_val in rp.rigging] 

return self.virtual.element_class(self.virtual, partition_list=partitions, 

rigging_list=riggings) 

 

def from_virtual(self, vrc): 

""" 

Convert ``vrc`` in the virtual crystal into a rigged configuration of 

the original Cartan type. 

 

INPUT: 

 

- ``vrc`` -- a virtual rigged configuration 

 

EXAMPLES:: 

 

sage: vct = CartanType(['C', 2]).as_folding() 

sage: RC = crystals.infinity.RiggedConfigurations(vct) 

sage: elt = RC(partition_list=[[3],[2]], rigging_list=[[-2],[0]]) 

sage: vrc_elt = RC.to_virtual(elt) 

sage: ret = RC.from_virtual(vrc_elt); ret 

<BLANKLINE> 

-3[ ][ ][ ]-2 

<BLANKLINE> 

-1[ ][ ]0 

<BLANKLINE> 

sage: ret == elt 

True 

""" 

gamma = list(self._folded_ct.scaling_factors()) #map(int, self._folded_ct.scaling_factors()) 

sigma = self._folded_ct._orbit 

n = self._cartan_type.rank() 

partitions = [None] * n 

riggings = [None] * n 

vindex = self._folded_ct._folding.index_set() 

# TODO: Handle special cases for A^{(2)} even and its dual? 

for a in range(n): 

index = vindex.index(sigma[a][0]) 

partitions[a] = [row_len // gamma[a] for row_len in vrc[index]._list] 

riggings[a] = [rig_val / gamma[a] for rig_val in vrc[index].rigging] 

return self.element_class(self, partition_list=partitions, 

rigging_list=riggings) 

 

class Element(RCNonSimplyLacedElement): 

""" 

A rigged configuration in `\mathcal{B}(\infty)` in 

non-simply-laced types. 

 

TESTS:: 

 

sage: vct = CartanType(['C', 3]).as_folding() 

sage: RC = crystals.infinity.RiggedConfigurations(vct) 

sage: elt = RC(partition_list=[[1],[1,1],[1]]) 

sage: TestSuite(elt).run() 

""" 

def weight(self): 

""" 

Return the weight of ``self``. 

 

EXAMPLES:: 

 

sage: vct = CartanType(['C', 3]).as_folding() 

sage: RC = crystals.infinity.RiggedConfigurations(vct) 

sage: elt = RC(partition_list=[[1],[1,1],[1]], rigging_list=[[0],[-1,-1],[0]]) 

sage: elt.weight() 

(-1, -1, 0) 

 

sage: vct = CartanType(['F', 4, 1]).as_folding() 

sage: RC = crystals.infinity.RiggedConfigurations(vct) 

sage: mg = RC.highest_weight_vector() 

sage: elt = mg.f_string([1,0,3,4,2,2]); ascii_art(elt) 

-1[ ]-1 0[ ]1 -2[ ][ ]-2 0[ ]1 -1[ ]-1 

sage: wt = elt.weight(); wt 

-Lambda[0] + Lambda[1] - 2*Lambda[2] + 3*Lambda[3] - Lambda[4] - delta 

sage: al = RC.weight_lattice_realization().simple_roots() 

sage: wt == -(al[0] + al[1] + 2*al[2] + al[3] + al[4]) 

True 

""" 

P = self.parent().weight_lattice_realization() 

alpha = list(P.simple_roots()) 

return -sum(sum(x) * alpha[i] for i,x in enumerate(self)) 

 

# deprecations from trac:18555 

from sage.misc.superseded import deprecated_function_alias 

InfinityCrystalOfRiggedConfigurations.global_options = deprecated_function_alias(18555, InfinityCrystalOfRiggedConfigurations.options)