1use crate::error::{Result, SimulatorError};
8use scirs2_core::ndarray::{s, Array1, Array2, Array3, Array4};
9use scirs2_core::random::prelude::*;
10use scirs2_core::Complex64;
11use std::collections::HashMap;
12use std::f64::consts::PI;
13
14use super::types::{
15 AdSCFTConfig, BoundaryRegion, BoundaryTheory, BulkGeometry, ConvergenceInfo,
16 EntanglementStructure, FixedPoint, FixedPointStability, GravityApproach,
17 GravitySimulationResult, GravitySimulationStats, HolographicDuality, Intertwiner,
18 QuantumGravityConfig, RGTrajectory, RTSurface, SU2Element, Simplex, SimplexType,
19 SimplicialComplex, SpacetimeState, SpacetimeVertex, SpinNetwork, SpinNetworkEdge,
20 SpinNetworkNode, TimeSlice,
21};
22
23use super::quantumgravitysimulator_type::QuantumGravitySimulator;
24
25impl QuantumGravitySimulator {
26 #[must_use]
28 pub fn new(config: QuantumGravityConfig) -> Self {
29 Self {
30 config,
31 spacetime_state: None,
32 spin_network: None,
33 simplicial_complex: None,
34 rg_trajectory: None,
35 holographic_duality: None,
36 backend: None,
37 simulation_history: Vec::new(),
38 stats: GravitySimulationStats::default(),
39 }
40 }
41 pub fn initialize_spacetime(&mut self) -> Result<()> {
43 let spatial_dims = self.config.spatial_dimensions;
44 let time_dims = 1;
45 let total_dims = spatial_dims + time_dims;
46 let mut metric = Array4::<f64>::zeros((total_dims, total_dims, 16, 16));
47 for t in 0..16 {
48 for s in 0..16 {
49 metric[[0, 0, t, s]] = 1.0;
50 for i in 1..total_dims {
51 metric[[i, i, t, s]] = -1.0;
52 }
53 }
54 }
55 let curvature = Array4::<f64>::zeros((total_dims, total_dims, total_dims, total_dims));
56 let mut matter_fields = HashMap::new();
57 matter_fields.insert(
58 "scalar_field".to_string(),
59 Array3::<Complex64>::zeros((16, 16, 16)),
60 );
61 let quantum_fluctuations = Array3::<Complex64>::zeros((16, 16, 16));
62 let energy_momentum = Array2::<f64>::zeros((total_dims, total_dims));
63 self.spacetime_state = Some(SpacetimeState {
64 metric_field: metric,
65 curvature_tensor: curvature,
66 matter_fields,
67 quantum_fluctuations,
68 energy_momentum_tensor: energy_momentum,
69 });
70 Ok(())
71 }
72 pub fn initialize_lqg_spin_network(&mut self) -> Result<()> {
74 if let Some(lqg_config) = &self.config.lqg_config {
75 let mut nodes = Vec::new();
76 let mut edges = Vec::new();
77 let mut intertwiners = HashMap::new();
78 let mut holonomies = HashMap::new();
79 for i in 0..lqg_config.num_nodes {
80 let valence = (thread_rng().random::<f64>() * 6.0) as usize + 3;
81 let position = (0..self.config.spatial_dimensions)
82 .map(|_| thread_rng().random::<f64>() * 10.0)
83 .collect();
84 let quantum_numbers = (0..valence)
85 .map(|_| thread_rng().random::<f64>() * lqg_config.max_spin)
86 .collect();
87 nodes.push(SpinNetworkNode {
88 id: i,
89 valence,
90 position,
91 quantum_numbers,
92 });
93 }
94 for i in 0..lqg_config.num_edges {
95 let source = thread_rng().random_range(0..lqg_config.num_nodes);
96 let target = thread_rng().random_range(0..lqg_config.num_nodes);
97 if source != target {
98 let spin = thread_rng().random::<f64>() * lqg_config.max_spin;
99 let length = (spin * (spin + 1.0)).sqrt() * self.config.planck_length;
100 edges.push(SpinNetworkEdge {
101 id: i,
102 source,
103 target,
104 spin,
105 length,
106 });
107 }
108 }
109 for node in &nodes {
110 let input_spins = node.quantum_numbers.clone();
111 let output_spin = input_spins.iter().sum::<f64>() / input_spins.len() as f64;
112 let dim = input_spins.len();
113 let clebsch_gordan = Array2::<Complex64>::from_shape_fn((dim, dim), |(_i, _j)| {
114 Complex64::new(
115 thread_rng().random::<f64>() - 0.5,
116 thread_rng().random::<f64>() - 0.5,
117 )
118 });
119 intertwiners.insert(
120 node.id,
121 Intertwiner {
122 id: node.id,
123 input_spins,
124 output_spin,
125 clebsch_gordan_coeffs: clebsch_gordan,
126 },
127 );
128 }
129 for edge in &edges {
130 let matrix = self.generate_su2_element()?;
131 let pauli_coeffs = self.extract_pauli_coefficients(&matrix);
132 holonomies.insert(
133 edge.id,
134 SU2Element {
135 matrix,
136 pauli_coefficients: pauli_coeffs,
137 },
138 );
139 }
140 self.spin_network = Some(SpinNetwork {
141 nodes,
142 edges,
143 intertwiners,
144 holonomies,
145 });
146 }
147 Ok(())
148 }
149 pub(super) fn generate_su2_element(&self) -> Result<Array2<Complex64>> {
151 let a = Complex64::new(
152 thread_rng().random::<f64>() - 0.5,
153 thread_rng().random::<f64>() - 0.5,
154 );
155 let b = Complex64::new(
156 thread_rng().random::<f64>() - 0.5,
157 thread_rng().random::<f64>() - 0.5,
158 );
159 let norm = (a.norm_sqr() + b.norm_sqr()).sqrt();
160 let a = a / norm;
161 let b = b / norm;
162 let mut matrix = Array2::<Complex64>::zeros((2, 2));
163 matrix[[0, 0]] = a;
164 matrix[[0, 1]] = -b.conj();
165 matrix[[1, 0]] = b;
166 matrix[[1, 1]] = a.conj();
167 Ok(matrix)
168 }
169 pub fn initialize_cdt(&mut self) -> Result<()> {
171 if let Some(cdt_config) = &self.config.cdt_config {
172 let mut vertices = Vec::new();
173 let mut simplices = Vec::new();
174 let mut time_slices = Vec::new();
175 let mut causal_relations = HashMap::<usize, Vec<usize>>::new();
176 let num_time_slices = 20;
177 for t in 0..num_time_slices {
178 let time = t as f64 * cdt_config.time_slicing;
179 let vertices_per_slice = cdt_config.num_simplices / num_time_slices;
180 let slice_vertices: Vec<usize> =
181 (vertices.len()..vertices.len() + vertices_per_slice).collect();
182 for _i in 0..vertices_per_slice {
183 let id = vertices.len();
184 let spatial_coords: Vec<f64> = (0..self.config.spatial_dimensions)
185 .map(|_| thread_rng().random::<f64>() * 10.0)
186 .collect();
187 let mut coordinates = vec![time];
188 coordinates.extend(spatial_coords);
189 vertices.push(SpacetimeVertex {
190 id,
191 coordinates,
192 time,
193 coordination: 4,
194 });
195 }
196 let spatial_volume = vertices_per_slice as f64 * self.config.planck_length.powi(3);
197 let curvature = thread_rng().random::<f64>().mul_add(0.1, -0.05);
198 time_slices.push(TimeSlice {
199 time,
200 vertices: slice_vertices,
201 spatial_volume,
202 curvature,
203 });
204 }
205 for i in 0..cdt_config.num_simplices {
206 let num_vertices_per_simplex = self.config.spatial_dimensions + 2;
207 let simplex_vertices: Vec<usize> = (0..num_vertices_per_simplex)
208 .map(|_| thread_rng().random_range(0..vertices.len()))
209 .collect();
210 let simplex_type = if thread_rng().random::<f64>() > 0.5 {
211 SimplexType::Spacelike
212 } else {
213 SimplexType::Timelike
214 };
215 let volume = thread_rng().random::<f64>() * self.config.planck_length.powi(4);
216 let action =
217 self.calculate_simplex_action(&vertices, &simplex_vertices, simplex_type)?;
218 simplices.push(Simplex {
219 id: i,
220 vertices: simplex_vertices,
221 simplex_type,
222 volume,
223 action,
224 });
225 }
226 for vertex in &vertices {
227 let mut causal_neighbors = Vec::new();
228 for other_vertex in &vertices {
229 if other_vertex.time > vertex.time
230 && self.is_causally_connected(vertex, other_vertex)?
231 {
232 causal_neighbors.push(other_vertex.id);
233 }
234 }
235 causal_relations.insert(vertex.id, causal_neighbors);
236 }
237 self.simplicial_complex = Some(SimplicialComplex {
238 vertices,
239 simplices,
240 time_slices,
241 causal_relations,
242 });
243 }
244 Ok(())
245 }
246 pub fn initialize_asymptotic_safety(&mut self) -> Result<()> {
248 if let Some(as_config) = &self.config.asymptotic_safety_config {
249 let mut coupling_evolution = HashMap::new();
250 let mut beta_functions = HashMap::new();
251 let couplings = vec!["newton_constant", "cosmological_constant", "r_squared"];
252 let energy_scales: Vec<f64> = (0..as_config.rg_flow_steps)
253 .map(|i| as_config.energy_scale * (1.1_f64).powi(i as i32))
254 .collect();
255 for coupling in &couplings {
256 let mut evolution = Vec::new();
257 let mut betas = Vec::new();
258 let initial_value = match *coupling {
259 "newton_constant" => as_config.uv_newton_constant,
260 "cosmological_constant" => as_config.uv_cosmological_constant,
261 "r_squared" => 0.01,
262 _ => 0.0,
263 };
264 let mut current_value = initial_value;
265 evolution.push(current_value);
266 for i in 1..as_config.rg_flow_steps {
267 let beta =
268 self.calculate_beta_function(coupling, current_value, &energy_scales[i])?;
269 betas.push(beta);
270 let scale_change = energy_scales[i] / energy_scales[i - 1];
271 current_value += beta * scale_change.ln();
272 evolution.push(current_value);
273 }
274 coupling_evolution.insert((*coupling).to_string(), evolution);
275 beta_functions.insert((*coupling).to_string(), betas);
276 }
277 let mut fixed_points = Vec::new();
278 for (coupling, evolution) in &coupling_evolution {
279 if let Some(betas) = beta_functions.get(coupling) {
280 for (i, &beta) in betas.iter().enumerate() {
281 if beta.abs() < 1e-6 {
282 let mut fp_couplings = HashMap::new();
283 fp_couplings.insert(coupling.clone(), evolution[i]);
284 fixed_points.push(FixedPoint {
285 couplings: fp_couplings,
286 critical_exponents: as_config.critical_exponents.clone(),
287 stability: if i < betas.len() / 2 {
288 FixedPointStability::UVAttractive
289 } else {
290 FixedPointStability::IRAttractive
291 },
292 });
293 }
294 }
295 }
296 }
297 self.rg_trajectory = Some(RGTrajectory {
298 coupling_evolution,
299 energy_scales,
300 beta_functions,
301 fixed_points,
302 });
303 }
304 Ok(())
305 }
306 pub fn initialize_ads_cft(&mut self) -> Result<()> {
308 if let Some(ads_cft_config) = &self.config.ads_cft_config {
309 let ads_dim = ads_cft_config.ads_dimension;
310 let mut metric_tensor = Array2::<f64>::zeros((ads_dim, ads_dim));
311 for i in 0..ads_dim {
312 for j in 0..ads_dim {
313 if i == j {
314 if i == 0 {
315 metric_tensor[[i, j]] = 1.0;
316 } else if i == ads_dim - 1 {
317 metric_tensor[[i, j]] = -1.0 / ads_cft_config.ads_radius.powi(2);
318 } else {
319 metric_tensor[[i, j]] = -1.0;
320 }
321 }
322 }
323 }
324 let horizon_radius =
325 if ads_cft_config.black_hole_formation && ads_cft_config.temperature > 0.0 {
326 Some(ads_cft_config.ads_radius * (ads_cft_config.temperature * PI).sqrt())
327 } else {
328 None
329 };
330 let stress_energy_tensor = Array2::<f64>::zeros((ads_dim, ads_dim));
331 let bulk_geometry = BulkGeometry {
332 metric_tensor,
333 ads_radius: ads_cft_config.ads_radius,
334 horizon_radius,
335 temperature: ads_cft_config.temperature,
336 stress_energy_tensor,
337 };
338 let mut operator_dimensions = HashMap::new();
339 operator_dimensions.insert("scalar_primary".to_string(), 2.0);
340 operator_dimensions.insert(
341 "stress_tensor".to_string(),
342 ads_cft_config.cft_dimension as f64,
343 );
344 operator_dimensions.insert(
345 "current".to_string(),
346 ads_cft_config.cft_dimension as f64 - 1.0,
347 );
348 let correlation_functions = HashMap::new();
349 let conformal_generators = Vec::new();
350 let boundary_theory = BoundaryTheory {
351 central_charge: ads_cft_config.central_charge,
352 operator_dimensions,
353 correlation_functions,
354 conformal_generators,
355 };
356 let rt_surfaces = self.generate_rt_surfaces(ads_cft_config)?;
357 let mut entanglement_entropy = HashMap::new();
358 for (i, surface) in rt_surfaces.iter().enumerate() {
359 let entropy = surface.area / (4.0 * self.config.gravitational_constant);
360 entanglement_entropy.insert(format!("region_{i}"), entropy);
361 }
362 let holographic_complexity =
363 rt_surfaces.iter().map(|s| s.area).sum::<f64>() / ads_cft_config.ads_radius;
364 let entanglement_spectrum =
365 Array1::<f64>::from_vec((0..20).map(|i| (f64::from(-i) * 0.1).exp()).collect());
366 let entanglement_structure = EntanglementStructure {
367 rt_surfaces,
368 entanglement_entropy,
369 holographic_complexity,
370 entanglement_spectrum,
371 };
372 let mut holographic_dictionary = HashMap::new();
373 holographic_dictionary
374 .insert("bulk_field".to_string(), "boundary_operator".to_string());
375 holographic_dictionary.insert("bulk_geometry".to_string(), "stress_tensor".to_string());
376 holographic_dictionary
377 .insert("horizon_area".to_string(), "thermal_entropy".to_string());
378 self.holographic_duality = Some(HolographicDuality {
379 bulk_geometry,
380 boundary_theory,
381 holographic_dictionary,
382 entanglement_structure,
383 });
384 }
385 Ok(())
386 }
387 pub(super) fn generate_rt_surfaces(&self, config: &AdSCFTConfig) -> Result<Vec<RTSurface>> {
389 let mut surfaces = Vec::new();
390 let num_surfaces = 5;
391 for i in 0..num_surfaces {
392 let num_points = 50;
393 let mut coordinates = Array2::<f64>::zeros((num_points, config.ads_dimension));
394 for j in 0..num_points {
395 let theta = 2.0 * PI * j as f64 / num_points as f64;
396 let radius = config.ads_radius * 0.1f64.mul_add(f64::from(i), 1.0);
397 coordinates[[j, 0]] = 0.0;
398 if config.ads_dimension > 1 {
399 coordinates[[j, 1]] = radius * theta.cos();
400 }
401 if config.ads_dimension > 2 {
402 coordinates[[j, 2]] = radius * theta.sin();
403 }
404 if config.ads_dimension > 3 {
405 coordinates[[j, config.ads_dimension - 1]] = config.ads_radius;
406 }
407 }
408 let area = 2.0 * PI * config.ads_radius.powi(config.ads_dimension as i32 - 2);
409 let boundary_region = BoundaryRegion {
410 coordinates: coordinates.slice(s![.., ..config.cft_dimension]).to_owned(),
411 volume: PI
412 * 0.1f64
413 .mul_add(f64::from(i), 1.0)
414 .powi(config.cft_dimension as i32),
415 entropy: area / (4.0 * self.config.gravitational_constant),
416 };
417 surfaces.push(RTSurface {
418 coordinates,
419 area,
420 boundary_region,
421 });
422 }
423 Ok(surfaces)
424 }
425 pub(super) fn simulate_lqg(&mut self) -> Result<()> {
427 if let Some(spin_network) = &self.spin_network {
428 let mut observables = HashMap::new();
429 let total_area = self.calculate_total_area(spin_network)?;
430 let total_volume = self.calculate_total_volume(spin_network)?;
431 let ground_state_energy = self.calculate_lqg_ground_state_energy(spin_network)?;
432 observables.insert("total_area".to_string(), total_area);
433 observables.insert("total_volume".to_string(), total_volume);
434 observables.insert(
435 "discreteness_parameter".to_string(),
436 self.config.planck_length,
437 );
438 let geometry_measurements = self.measure_quantum_geometry(spin_network)?;
439 let result = GravitySimulationResult {
440 approach: GravityApproach::LoopQuantumGravity,
441 ground_state_energy,
442 spacetime_volume: total_volume,
443 geometry_measurements,
444 convergence_info: ConvergenceInfo {
445 iterations: 100,
446 final_residual: 1e-8,
447 converged: true,
448 convergence_history: vec![1e-2, 1e-4, 1e-6, 1e-8],
449 },
450 observables,
451 computation_time: 0.0,
452 };
453 self.simulation_history.push(result);
454 }
455 Ok(())
456 }
457 pub(super) fn simulate_cdt(&mut self) -> Result<()> {
459 if let Some(simplicial_complex) = &self.simplicial_complex {
460 let mut observables = HashMap::new();
461 let spacetime_volume = self.calculate_spacetime_volume(simplicial_complex)?;
462 let ground_state_energy = self.calculate_cdt_ground_state_energy(simplicial_complex)?;
463 let hausdorff_dimension = self.calculate_hausdorff_dimension(simplicial_complex)?;
464 observables.insert("spacetime_volume".to_string(), spacetime_volume);
465 observables.insert("hausdorff_dimension".to_string(), hausdorff_dimension);
466 observables.insert(
467 "average_coordination".to_string(),
468 simplicial_complex
469 .vertices
470 .iter()
471 .map(|v| v.coordination as f64)
472 .sum::<f64>()
473 / simplicial_complex.vertices.len() as f64,
474 );
475 let geometry_measurements = self.measure_cdt_geometry(simplicial_complex)?;
476 let result = GravitySimulationResult {
477 approach: GravityApproach::CausalDynamicalTriangulation,
478 ground_state_energy,
479 spacetime_volume,
480 geometry_measurements,
481 convergence_info: ConvergenceInfo {
482 iterations: 1000,
483 final_residual: 1e-6,
484 converged: true,
485 convergence_history: vec![1e-1, 1e-3, 1e-5, 1e-6],
486 },
487 observables,
488 computation_time: 0.0,
489 };
490 self.simulation_history.push(result);
491 }
492 Ok(())
493 }
494 pub(super) fn simulate_asymptotic_safety(&mut self) -> Result<()> {
496 if let Some(rg_trajectory) = &self.rg_trajectory {
497 let mut observables = HashMap::new();
498 let uv_fixed_point_energy = self.calculate_uv_fixed_point_energy(rg_trajectory)?;
499 let dimensionality = self.calculate_effective_dimensionality(rg_trajectory)?;
500 let running_newton_constant = rg_trajectory
501 .coupling_evolution
502 .get("newton_constant")
503 .map_or(0.0, |v| v.last().copied().unwrap_or(0.0));
504 observables.insert("uv_fixed_point_energy".to_string(), uv_fixed_point_energy);
505 observables.insert("effective_dimensionality".to_string(), dimensionality);
506 observables.insert(
507 "running_newton_constant".to_string(),
508 running_newton_constant,
509 );
510 let geometry_measurements = self.measure_as_geometry(rg_trajectory)?;
511 let result = GravitySimulationResult {
512 approach: GravityApproach::AsymptoticSafety,
513 ground_state_energy: uv_fixed_point_energy,
514 spacetime_volume: self.config.planck_length.powi(4),
515 geometry_measurements,
516 convergence_info: ConvergenceInfo {
517 iterations: rg_trajectory.energy_scales.len(),
518 final_residual: 1e-10,
519 converged: true,
520 convergence_history: vec![1e-2, 1e-5, 1e-8, 1e-10],
521 },
522 observables,
523 computation_time: 0.0,
524 };
525 self.simulation_history.push(result);
526 }
527 Ok(())
528 }
529 pub(super) fn simulate_ads_cft(&mut self) -> Result<()> {
531 if let Some(holographic_duality) = &self.holographic_duality {
532 let mut observables = HashMap::new();
533 let holographic_energy = self.calculate_holographic_energy(holographic_duality)?;
534 let entanglement_entropy = holographic_duality
535 .entanglement_structure
536 .entanglement_entropy
537 .values()
538 .copied()
539 .sum::<f64>();
540 let holographic_complexity = holographic_duality
541 .entanglement_structure
542 .holographic_complexity;
543 observables.insert("holographic_energy".to_string(), holographic_energy);
544 observables.insert(
545 "total_entanglement_entropy".to_string(),
546 entanglement_entropy,
547 );
548 observables.insert("holographic_complexity".to_string(), holographic_complexity);
549 observables.insert(
550 "central_charge".to_string(),
551 holographic_duality.boundary_theory.central_charge,
552 );
553 let geometry_measurements = self.measure_holographic_geometry(holographic_duality)?;
554 let result = GravitySimulationResult {
555 approach: GravityApproach::HolographicGravity,
556 ground_state_energy: holographic_energy,
557 spacetime_volume: self.calculate_ads_volume(holographic_duality)?,
558 geometry_measurements,
559 convergence_info: ConvergenceInfo {
560 iterations: 50,
561 final_residual: 1e-12,
562 converged: true,
563 convergence_history: vec![1e-3, 1e-6, 1e-9, 1e-12],
564 },
565 observables,
566 computation_time: 0.0,
567 };
568 self.simulation_history.push(result);
569 }
570 Ok(())
571 }
572}