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C10-2 范畴论形式化规范

模块依赖​

from typing import Set, Dict, Tuple, List, Optional, Callable, Generic, TypeVar
from dataclasses import dataclass, field
from abc import ABC, abstractmethod
from enum import Enum
import hashlib
from no11_number_system import No11Number
from test_C10_1 import (
FormalSystem, Formula, Proof, Symbol, SymbolType,
Model, Interpretation, GödelEncoder
)

核心数据结构​

基本范畴元素​

@dataclass(frozen=True)
class CategoryObject:
"""范畴中的对象"""
name: str
data: any # 可以是形式系统、集合、空间等

def encode(self) -> No11Number:
"""对象的No-11编码"""
hash_val = hash((self.name, type(self.data).__name__))
return No11Number(abs(hash_val) % 10000)

def __hash__(self) -> int:
return hash((self.name, id(self.data)))

@dataclass(frozen=True)
class Morphism:
"""范畴中的态射"""
source: CategoryObject
target: CategoryObject
name: str
mapping: Optional[Callable] = None

def __post_init__(self):
if self.mapping is None:
# 默认为恒等映射的标记
object.__setattr__(self, 'mapping', lambda x: x)

def apply(self, element: any) -> any:
"""应用态射"""
if self.mapping:
return self.mapping(element)
return element

def encode(self) -> No11Number:
"""态射的No-11编码"""
src_code = self.source.encode().value
tgt_code = self.target.encode().value
name_hash = sum(ord(c) for c in self.name) % 100
return No11Number((src_code * 100 + tgt_code) * 100 + name_hash)

def __hash__(self) -> int:
return hash((self.source, self.target, self.name))

@dataclass(frozen=True)
class IdentityMorphism(Morphism):
"""恒等态射"""
def __init__(self, obj: CategoryObject):
super().__init__(
source=obj,
target=obj,
name=f"id_{obj.name}",
mapping=lambda x: x
)

@dataclass(frozen=True)
class ComposedMorphism(Morphism):
"""复合态射"""
first: Morphism # f: A → B
second: Morphism # g: B → C

def __post_init__(self):
# 验证可复合性
if self.first.target != self.second.source:
raise ValueError(f"Morphisms {self.first.name} and {self.second.name} are not composable")

# 设置复合态射的源和目标
object.__setattr__(self, 'source', self.first.source)
object.__setattr__(self, 'target', self.second.target)
object.__setattr__(self, 'name', f"{self.second.name}∘{self.first.name}")

# 复合映射
def composed_mapping(x):
return self.second.apply(self.first.apply(x))
object.__setattr__(self, 'mapping', composed_mapping)

范畴定义​

class CategoryError(Exception):
"""范畴论错误基类"""
pass

class Category:
"""范畴的完整实现"""
def __init__(self, name: str):
self.name = name
self.objects: Set[CategoryObject] = set()
self.morphisms: Dict[Tuple[CategoryObject, CategoryObject], Set[Morphism]] = {}
self._identity_morphisms: Dict[CategoryObject, IdentityMorphism] = {}

def add_object(self, obj: CategoryObject):
"""添加对象到范畴"""
if obj in self.objects:
return

self.objects.add(obj)
# 自动创建恒等态射
id_mor = IdentityMorphism(obj)
self._identity_morphisms[obj] = id_mor
self.add_morphism(id_mor)

def add_morphism(self, morphism: Morphism):
"""添加态射到范畴"""
# 确保源和目标对象都在范畴中
if morphism.source not in self.objects:
self.add_object(morphism.source)
if morphism.target not in self.objects:
self.add_object(morphism.target)

key = (morphism.source, morphism.target)
if key not in self.morphisms:
self.morphisms[key] = set()
self.morphisms[key].add(morphism)

def compose(self, g: Morphism, f: Morphism) -> Morphism:
"""复合两个态射: g ∘ f"""
if f.target != g.source:
raise CategoryError(f"Cannot compose {f.name}: {f.source.name}→{f.target.name} "
f"with {g.name}: {g.source.name}→{g.target.name}")

# 检查特殊情况
if isinstance(f, IdentityMorphism):
return g
if isinstance(g, IdentityMorphism):
return f

return ComposedMorphism(f, g)

def identity(self, obj: CategoryObject) -> IdentityMorphism:
"""获取对象的恒等态射"""
if obj not in self.objects:
raise CategoryError(f"Object {obj.name} not in category")
return self._identity_morphisms[obj]

def hom(self, source: CategoryObject, target: CategoryObject) -> Set[Morphism]:
"""获取hom-集 Hom(source, target)"""
return self.morphisms.get((source, target), set())

def is_isomorphism(self, f: Morphism) -> bool:
"""检查态射是否是同构"""
# 寻找逆态射
candidates = self.hom(f.target, f.source)
for g in candidates:
if (self.compose(g, f) == self.identity(f.source) and
self.compose(f, g) == self.identity(f.target)):
return True
return False

def verify_axioms(self) -> bool:
"""验证范畴公理"""
# 1. 恒等态射存在性
for obj in self.objects:
if obj not in self._identity_morphisms:
return False

# 2. 复合的结合律
# 选择三个可复合的态射进行测试
for morphisms_list in self.morphisms.values():
for f in morphisms_list:
for g_set in self.morphisms.get((f.target, f.target), []):
for g in g_set:
for h_set in self.morphisms.get((g.target, g.target), []):
for h in h_set:
# 验证 h∘(g∘f) = (h∘g)∘f
left = self.compose(h, self.compose(g, f))
right = self.compose(self.compose(h, g), f)
if left != right:
return False

# 3. 单位律
for mor in sum(self.morphisms.values(), []):
id_src = self.identity(mor.source)
id_tgt = self.identity(mor.target)
if (self.compose(mor, id_src) != mor or
self.compose(id_tgt, mor) != mor):
return False

return True

def encode(self) -> No11Number:
"""范畴的No-11编码"""
obj_sum = sum(obj.encode().value for obj in self.objects)
mor_sum = sum(mor.encode().value for mors in self.morphisms.values() for mor in mors)
return No11Number((obj_sum + mor_sum) % 100000)

函子定义​

@dataclass
class Functor:
"""函子 F: C → D"""
name: str
source: Category
target: Category
object_map: Dict[CategoryObject, CategoryObject] = field(default_factory=dict)
morphism_map: Dict[Morphism, Morphism] = field(default_factory=dict)

def map_object(self, obj: CategoryObject) -> CategoryObject:
"""对象的函子映射"""
if obj not in self.object_map:
raise CategoryError(f"Object {obj.name} not in functor domain")
return self.object_map[obj]

def map_morphism(self, mor: Morphism) -> Morphism:
"""态射的函子映射"""
if mor not in self.morphism_map:
# 尝试从已知映射推导
if isinstance(mor, IdentityMorphism):
# F(id_A) = id_F(A)
f_obj = self.map_object(mor.source)
return self.target.identity(f_obj)
elif isinstance(mor, ComposedMorphism):
# F(g∘f) = F(g)∘F(f)
f_first = self.map_morphism(mor.first)
f_second = self.map_morphism(mor.second)
return self.target.compose(f_second, f_first)
else:
raise CategoryError(f"Morphism {mor.name} not in functor domain")
return self.morphism_map[mor]

def verify_functoriality(self) -> bool:
"""验证函子性质"""
# 1. 保持恒等态射
for obj in self.source.objects:
if obj in self.object_map:
id_obj = self.source.identity(obj)
f_id = self.map_morphism(id_obj)
expected_id = self.target.identity(self.map_object(obj))
if f_id != expected_id:
return False

# 2. 保持态射复合
for mor_set in self.source.morphisms.values():
for f in mor_set:
if f not in self.morphism_map:
continue
for g_set in self.source.hom(f.target, f.target):
for g in g_set:
if g not in self.morphism_map:
continue
# 验证 F(g∘f) = F(g)∘F(f)
composed = self.source.compose(g, f)
f_composed = self.map_morphism(composed)
f_f = self.map_morphism(f)
f_g = self.map_morphism(g)
expected = self.target.compose(f_g, f_f)
if f_composed != expected:
return False

return True

def is_faithful(self) -> bool:
"""检查函子是否忠实"""
# 单射性检查:不同的态射映射到不同的态射
mapped_morphisms = set()
for mor in self.morphism_map:
f_mor = self.morphism_map[mor]
if f_mor in mapped_morphisms:
return False
mapped_morphisms.add(f_mor)
return True

def is_full(self) -> bool:
"""检查函子是否满"""
# 对每对映射后的对象,检查是否所有态射都来自原范畴
for obj1 in self.object_map:
for obj2 in self.object_map:
f_obj1 = self.map_object(obj1)
f_obj2 = self.map_object(obj2)

# 目标范畴中的所有态射
target_hom = self.target.hom(f_obj1, f_obj2)

# 源范畴中对应态射的像
source_hom = self.source.hom(obj1, obj2)
mapped_hom = {self.map_morphism(f) for f in source_hom if f in self.morphism_map}

if mapped_hom != target_hom:
return False

return True

自然变换定义​

@dataclass
class NaturalTransformation:
"""自然变换 η: F ⇒ G"""
name: str
source: Functor # F: C → D
target: Functor # G: C → D
components: Dict[CategoryObject, Morphism] = field(default_factory=dict)

def __post_init__(self):
# 验证源函子和目标函子有相同的域和陪域
if self.source.source != self.target.source:
raise CategoryError("Source functors must have same domain")
if self.source.target != self.target.target:
raise CategoryError("Target functors must have same codomain")

def component_at(self, obj: CategoryObject) -> Morphism:
"""获取在对象处的分量 η_A: F(A) → G(A)"""
if obj not in self.components:
raise CategoryError(f"No component at object {obj.name}")
return self.components[obj]

def verify_naturality(self) -> bool:
"""验证自然性条件"""
C = self.source.source # 源范畴
D = self.source.target # 目标范畴

# 对源范畴中的每个态射 f: A → B
for mor_set in C.morphisms.values():
for f in mor_set:
A, B = f.source, f.target

# 检查分量是否都存在
if A not in self.components or B not in self.components:
continue

# 获取相关的对象和态射
FA = self.source.map_object(A)
FB = self.source.map_object(B)
GA = self.target.map_object(A)
GB = self.target.map_object(B)

Ff = self.source.map_morphism(f) # F(f): F(A) → F(B)
Gf = self.target.map_morphism(f) # G(f): G(A) → G(B)

eta_A = self.component_at(A) # η_A: F(A) → G(A)
eta_B = self.component_at(B) # η_B: F(B) → G(B)

# 验证交换性: η_B ∘ F(f) = G(f) ∘ η_A
left = D.compose(eta_B, Ff)
right = D.compose(Gf, eta_A)

if left != right:
return False

return True

def is_isomorphism(self) -> bool:
"""检查是否是自然同构"""
# 每个分量都必须是同构
for obj, component in self.components.items():
if not self.source.target.is_isomorphism(component):
return False
return True

极限和余极限​

@dataclass
class Cone:
"""锥:极限的候选"""
apex: CategoryObject
diagram: Dict[CategoryObject, CategoryObject] # 图表
projections: Dict[CategoryObject, Morphism] # 投影态射

def verify_commutativity(self, category: Category) -> bool:
"""验证锥的交换性"""
# 对图表中的每个态射,验证相应的三角交换
return True

@dataclass
class Limit:
"""极限"""
cone: Cone
universal_property: Callable[[Cone], Morphism] # 泛性质

def is_product(self) -> bool:
"""检查是否是积"""
return len(self.cone.diagram) == 2

def is_equalizer(self) -> bool:
"""检查是否是等化子"""
# 特殊的极限类型
return False

@dataclass
class Colimit:
"""余极限"""
cocone: 'Cocone'
universal_property: Callable[['Cocone'], Morphism]

def is_coproduct(self) -> bool:
"""检查是否是余积"""
return len(self.cocone.diagram) == 2

def is_coequalizer(self) -> bool:
"""检查是否是余等化子"""
return False

伴随函子​

@dataclass
class Adjunction:
"""伴随 F ⊣ G"""
left: Functor # F: C → D
right: Functor # G: D → C
unit: NaturalTransformation # η: Id_C ⇒ G∘F
counit: NaturalTransformation # ε: F∘G ⇒ Id_D

def verify_triangle_identities(self) -> bool:
"""验证三角恒等式"""
# 1. (ε * F) ∘ (F * η) = id_F
# 2. (G * ε) ∘ (η * G) = id_G
return True

def hom_isomorphism(self, c: CategoryObject, d: CategoryObject) -> Tuple[Callable, Callable]:
"""同构 Hom_D(F(c), d) ≅ Hom_C(c, G(d))"""
def forward(f: Morphism) -> Morphism:
# f: F(c) → d 映射到 G(f) ∘ η_c: c → G(d)
pass

def backward(g: Morphism) -> Morphism:
# g: c → G(d) 映射到 ε_d ∘ F(g): F(c) → d
pass

return forward, backward

2-范畴结构​

class TwoCategory:
"""2-范畴"""
def __init__(self, name: str):
self.name = name
self.objects: Set[Category] = set() # 0-胞
self.morphisms: Dict[Tuple[Category, Category], Set[Functor]] = {} # 1-胞
self.two_morphisms: Dict[Tuple[Functor, Functor], Set[NaturalTransformation]] = {} # 2-胞

def vertical_composition(self, beta: NaturalTransformation,
alpha: NaturalTransformation) -> NaturalTransformation:
"""垂直复合 β • α"""
if alpha.target != beta.source:
raise CategoryError("Natural transformations not vertically composable")

# (β • α)_A = β_A ∘ α_A
components = {}
for obj in alpha.components:
components[obj] = alpha.source.target.compose(
beta.component_at(obj),
alpha.component_at(obj)
)

return NaturalTransformation(
name=f"{beta.name}•{alpha.name}",
source=alpha.source,
target=beta.target,
components=components
)

def horizontal_composition(self, beta: NaturalTransformation,
alpha: NaturalTransformation) -> NaturalTransformation:
"""水平复合 β * α"""
# 需要函子复合
pass

Topos结构​

class ElementaryTopos(Category):
"""初等topos"""
def __init__(self, name: str):
super().__init__(name)
self.terminal_object: Optional[CategoryObject] = None
self.subobject_classifier: Optional[CategoryObject] = None
self.truth_morphism: Optional[Morphism] = None

def has_finite_limits(self) -> bool:
"""检查是否有有限极限"""
return True

def has_exponentials(self) -> bool:
"""检查是否有指数对象"""
return True

def internal_logic(self) -> 'InternalLogic':
"""获取内部逻辑"""
return InternalLogic(self)

def is_boolean(self) -> bool:
"""检查是否是布尔topos"""
# 子对象格是布尔代数
return False

范畴等价​

@dataclass
class Equivalence:
"""范畴等价"""
functor: Functor # F: C → D
quasi_inverse: Functor # G: D → C
unit_iso: NaturalTransformation # η: Id_C ⇒ G∘F (自然同构)
counit_iso: NaturalTransformation # ε: F∘G ⇒ Id_D (自然同构)

def verify_equivalence(self) -> bool:
"""验证等价条件"""
# 1. η 和 ε 都是自然同构
if not self.unit_iso.is_isomorphism() or not self.counit_iso.is_isomorphism():
return False

# 2. 函子是本质满的
# 3. 函子是忠实的
return True

算法实现​

Collapse函子​

class CollapseFunctor(Functor):
"""Collapse函子的特殊实现"""
def __init__(self, category: Category):
super().__init__(
name="Collapse",
source=category,
target=category
)
self._compute_collapse_mapping()

def _compute_collapse_mapping(self):
"""计算collapse映射"""
# 移除冗余结构
for obj in self.source.objects:
collapsed_obj = self._collapse_object(obj)
self.object_map[obj] = collapsed_obj

for mor_set in self.source.morphisms.values():
for mor in mor_set:
collapsed_mor = self._collapse_morphism(mor)
self.morphism_map[mor] = collapsed_mor

def _collapse_object(self, obj: CategoryObject) -> CategoryObject:
"""对象的collapse"""
# 如果对象包含形式系统,移除冗余公理
if isinstance(obj.data, FormalSystem):
collapsed_system = self._collapse_formal_system(obj.data)
return CategoryObject(f"collapsed_{obj.name}", collapsed_system)
return obj

def _collapse_morphism(self, mor: Morphism) -> Morphism:
"""态射的collapse"""
# 简化复合态射链
if isinstance(mor, ComposedMorphism):
# 尝试简化
return self._simplify_composition(mor)
return mor

def _collapse_formal_system(self, system: FormalSystem) -> FormalSystem:
"""形式系统的collapse"""
# 实现来自C10-1
pass

def _simplify_composition(self, mor: ComposedMorphism) -> Morphism:
"""简化复合态射"""
# 递归简化
return mor

Yoneda嵌入​

class YonedaEmbedding:
"""Yoneda嵌入 Y: C → [C^op, Set]"""
def __init__(self, category: Category):
self.category = category
self.presheaf_category = self._construct_presheaf_category()

def _construct_presheaf_category(self) -> Category:
"""构造预层范畴"""
presheaves = Category(f"[{self.category.name}^op, Set_no11]")

# 每个对象A产生预层Hom(-, A)
for obj in self.category.objects:
presheaf = self._hom_presheaf(obj)
presheaves.add_object(presheaf)

return presheaves

def _hom_presheaf(self, obj: CategoryObject) -> CategoryObject:
"""构造Hom(-, A)预层"""
def presheaf_data(x: CategoryObject) -> Set[Morphism]:
return self.category.hom(x, obj)

return CategoryObject(f"Hom(-,{obj.name})", presheaf_data)

def embed(self, obj: CategoryObject) -> CategoryObject:
"""嵌入对象"""
return self._hom_presheaf(obj)

def yoneda_lemma(self, presheaf: CategoryObject, obj: CategoryObject) -> bool:
"""验证Yoneda引理:Nat(Hom(-,A), F) ≅ F(A)"""
# 自然变换与元素的双射
return True

接口规范​

范畴论系统接口​

class CategoryTheoryInterface:
"""范畴论系统的标准接口"""
def create_category(self, name: str) -> Category:
"""创建范畴"""
pass

def create_functor(self, name: str, source: Category, target: Category) -> Functor:
"""创建函子"""
pass

def create_natural_transformation(self, name: str,
source: Functor,
target: Functor) -> NaturalTransformation:
"""创建自然变换"""
pass

def compute_limit(self, diagram: Dict[CategoryObject, Morphism]) -> Limit:
"""计算极限"""
pass

def find_adjunction(self, left: Functor, right: Functor) -> Optional[Adjunction]:
"""寻找伴随"""
pass

def check_equivalence(self, C: Category, D: Category) -> Optional[Equivalence]:
"""检查范畴等价"""
pass

验证规范​

公理验证​

def verify_category_axioms(category: Category) -> bool:
"""验证范畴公理"""
# 1. 态射复合的结合律
# 2. 恒等态射的存在性
# 3. 单位律
return category.verify_axioms()

函子性验证​

def verify_functor_properties(functor: Functor) -> bool:
"""验证函子性质"""
# 1. 保持恒等态射
# 2. 保持态射复合
return functor.verify_functoriality()

自然性验证​

def verify_naturality(nat: NaturalTransformation) -> bool:
"""验证自然性"""
return nat.verify_naturality()

错误处理规范​

所有范畴操作必须进行严格的错误检查:

  1. 对象错误: 对象必须在范畴中
  2. 态射错误: 态射的源和目标必须正确
  3. 复合错误: 只有可复合的态射才能复合
  4. 函子错误: 映射必须保持结构
  5. 自然性错误: 必须满足交换图

性能要求​

  1. 对象查找: O(1) 使用集合
  2. 态射查找: O(1) 使用字典
  3. 复合运算: O(1) 对简单态射
  4. 公理验证: O(n³) 其中n是态射数
  5. 等价判定: 指数级,需要优化

测试规范​

每个范畴组件必须通过以下测试:

  1. 基础测试: 对象和态射的创建
  2. 复合测试: 态射复合的正确性
  3. 公理测试: 范畴公理的满足
  4. 函子测试: 函子性质的保持
  5. 极限测试: 极限的构造和泛性质
  6. 高级测试: 伴随、等价等高级概念