Home | Metamath
Proof Explorer Theorem List (p. 72 of 450) | < Previous Next > |
Bad symbols? Try the
GIF version. |
||
Mirrors > Metamath Home Page > MPE Home Page > Theorem List Contents > Recent Proofs This page: Page List |
Color key: | Metamath Proof Explorer
(1-28697) |
Hilbert Space Explorer
(28698-30220) |
Users' Mathboxes
(30221-44913) |
Type | Label | Description |
---|---|---|
Statement | ||
Theorem | isopo 7101 | An isomorphism preserves partial ordering. (Contributed by Stefan O'Rear, 16-Nov-2014.) |
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝑅 Po 𝐴 ↔ 𝑆 Po 𝐵)) | ||
Theorem | isosolem 7102 | Lemma for isoso 7103. (Contributed by Stefan O'Rear, 16-Nov-2014.) |
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝑆 Or 𝐵 → 𝑅 Or 𝐴)) | ||
Theorem | isoso 7103 | An isomorphism preserves strict ordering. (Contributed by Stefan O'Rear, 16-Nov-2014.) |
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝑅 Or 𝐴 ↔ 𝑆 Or 𝐵)) | ||
Theorem | isowe 7104 | An isomorphism preserves well-ordering. Proposition 6.32(3) of [TakeutiZaring] p. 33. (Contributed by NM, 30-Apr-2004.) (Revised by Mario Carneiro, 18-Nov-2014.) |
⊢ (𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) → (𝑅 We 𝐴 ↔ 𝑆 We 𝐵)) | ||
Theorem | isowe2 7105* | A weak form of isowe 7104 that does not need Replacement. (Contributed by Mario Carneiro, 18-Nov-2014.) |
⊢ ((𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ ∀𝑥(𝐻 “ 𝑥) ∈ V) → (𝑆 We 𝐵 → 𝑅 We 𝐴)) | ||
Theorem | f1oiso 7106* | Any one-to-one onto function determines an isomorphism with an induced relation 𝑆. Proposition 6.33 of [TakeutiZaring] p. 34. (Contributed by NM, 30-Apr-2004.) |
⊢ ((𝐻:𝐴–1-1-onto→𝐵 ∧ 𝑆 = {〈𝑧, 𝑤〉 ∣ ∃𝑥 ∈ 𝐴 ∃𝑦 ∈ 𝐴 ((𝑧 = (𝐻‘𝑥) ∧ 𝑤 = (𝐻‘𝑦)) ∧ 𝑥𝑅𝑦)}) → 𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵)) | ||
Theorem | f1oiso2 7107* | Any one-to-one onto function determines an isomorphism with an induced relation 𝑆. (Contributed by Mario Carneiro, 9-Mar-2013.) |
⊢ 𝑆 = {〈𝑥, 𝑦〉 ∣ ((𝑥 ∈ 𝐵 ∧ 𝑦 ∈ 𝐵) ∧ (◡𝐻‘𝑥)𝑅(◡𝐻‘𝑦))} ⇒ ⊢ (𝐻:𝐴–1-1-onto→𝐵 → 𝐻 Isom 𝑅, 𝑆 (𝐴, 𝐵)) | ||
Theorem | f1owe 7108* | Well-ordering of isomorphic relations. (Contributed by NM, 4-Mar-1997.) |
⊢ 𝑅 = {〈𝑥, 𝑦〉 ∣ (𝐹‘𝑥)𝑆(𝐹‘𝑦)} ⇒ ⊢ (𝐹:𝐴–1-1-onto→𝐵 → (𝑆 We 𝐵 → 𝑅 We 𝐴)) | ||
Theorem | weniso 7109 | A set-like well-ordering has no nontrivial automorphisms. (Contributed by Stefan O'Rear, 16-Nov-2014.) (Revised by Mario Carneiro, 25-Jun-2015.) |
⊢ ((𝑅 We 𝐴 ∧ 𝑅 Se 𝐴 ∧ 𝐹 Isom 𝑅, 𝑅 (𝐴, 𝐴)) → 𝐹 = ( I ↾ 𝐴)) | ||
Theorem | weisoeq 7110 | Thus, there is at most one isomorphism between any two set-like well-ordered classes. Class version of wemoiso 7676. (Contributed by Mario Carneiro, 25-Jun-2015.) |
⊢ (((𝑅 We 𝐴 ∧ 𝑅 Se 𝐴) ∧ (𝐹 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐺 Isom 𝑅, 𝑆 (𝐴, 𝐵))) → 𝐹 = 𝐺) | ||
Theorem | weisoeq2 7111 | Thus, there is at most one isomorphism between any two set-like well-ordered classes. Class version of wemoiso2 7677. (Contributed by Mario Carneiro, 25-Jun-2015.) |
⊢ (((𝑆 We 𝐵 ∧ 𝑆 Se 𝐵) ∧ (𝐹 Isom 𝑅, 𝑆 (𝐴, 𝐵) ∧ 𝐺 Isom 𝑅, 𝑆 (𝐴, 𝐵))) → 𝐹 = 𝐺) | ||
Theorem | knatar 7112* | The Knaster-Tarski theorem says that every monotone function over a complete lattice has a (least) fixpoint. Here we specialize this theorem to the case when the lattice is the powerset lattice 𝒫 𝐴. (Contributed by Mario Carneiro, 11-Jun-2015.) |
⊢ 𝑋 = ∩ {𝑧 ∈ 𝒫 𝐴 ∣ (𝐹‘𝑧) ⊆ 𝑧} ⇒ ⊢ ((𝐴 ∈ 𝑉 ∧ (𝐹‘𝐴) ⊆ 𝐴 ∧ ∀𝑥 ∈ 𝒫 𝐴∀𝑦 ∈ 𝒫 𝑥(𝐹‘𝑦) ⊆ (𝐹‘𝑥)) → (𝑋 ⊆ 𝐴 ∧ (𝐹‘𝑋) = 𝑋)) | ||
Theorem | canth 7113 | No set 𝐴 is equinumerous to its power set (Cantor's theorem), i.e. no function can map 𝐴 it onto its power set. Compare Theorem 6B(b) of [Enderton] p. 132. For the equinumerosity version, see canth2 8672. Note that 𝐴 must be a set: this theorem does not hold when 𝐴 is too large to be a set; see ncanth 7114 for a counterexample. (Use nex 1801 if you want the form ¬ ∃𝑓𝑓:𝐴–onto→𝒫 𝐴.) (Contributed by NM, 7-Aug-1994.) (Proof shortened by Mario Carneiro, 7-Jun-2016.) |
⊢ 𝐴 ∈ V ⇒ ⊢ ¬ 𝐹:𝐴–onto→𝒫 𝐴 | ||
Theorem | ncanth 7114 |
Cantor's theorem fails for the universal class (which is not a set but a
proper class by vprc 5221). Specifically, the identity function maps
the
universe onto its power class. Compare canth 7113 that works for sets.
This failure comes from a limitation of the collection principle (which is necessary to avoid Russell's paradox ru 3773): 𝒫 V, being a class, cannot contain proper classes, so it is no larger than V, which is why the identity function "succeeds" in being surjective onto 𝒫 V (see pwv 4837). See also the remark in ru 3773 about NF, in which Cantor's theorem fails for sets that are "too large". This theorem gives some intuition behind that failure: in NF the universal class is a set, and it equals its own power set. (Contributed by NM, 29-Jun-2004.) (Proof shortened by BJ, 29-Dec-2023.) |
⊢ I :V–onto→𝒫 V | ||
Syntax | crio 7115 | Extend class notation with restricted description binder. |
class (℩𝑥 ∈ 𝐴 𝜑) | ||
Definition | df-riota 7116 | Define restricted description binder. In case there is no unique 𝑥 such that (𝑥 ∈ 𝐴 ∧ 𝜑) holds, it evaluates to the empty set. See also comments for df-iota 6316. (Contributed by NM, 15-Sep-2011.) (Revised by Mario Carneiro, 15-Oct-2016.) (Revised by NM, 2-Sep-2018.) |
⊢ (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑥(𝑥 ∈ 𝐴 ∧ 𝜑)) | ||
Theorem | riotaeqdv 7117* | Formula-building deduction for iota. (Contributed by NM, 15-Sep-2011.) |
⊢ (𝜑 → 𝐴 = 𝐵) ⇒ ⊢ (𝜑 → (℩𝑥 ∈ 𝐴 𝜓) = (℩𝑥 ∈ 𝐵 𝜓)) | ||
Theorem | riotabidv 7118* | Formula-building deduction for restricted iota. (Contributed by NM, 15-Sep-2011.) |
⊢ (𝜑 → (𝜓 ↔ 𝜒)) ⇒ ⊢ (𝜑 → (℩𝑥 ∈ 𝐴 𝜓) = (℩𝑥 ∈ 𝐴 𝜒)) | ||
Theorem | riotaeqbidv 7119* | Equality deduction for restricted universal quantifier. (Contributed by NM, 15-Sep-2011.) |
⊢ (𝜑 → 𝐴 = 𝐵) & ⊢ (𝜑 → (𝜓 ↔ 𝜒)) ⇒ ⊢ (𝜑 → (℩𝑥 ∈ 𝐴 𝜓) = (℩𝑥 ∈ 𝐵 𝜒)) | ||
Theorem | riotaex 7120 | Restricted iota is a set. (Contributed by NM, 15-Sep-2011.) |
⊢ (℩𝑥 ∈ 𝐴 𝜓) ∈ V | ||
Theorem | riotav 7121 | An iota restricted to the universe is unrestricted. (Contributed by NM, 18-Sep-2011.) |
⊢ (℩𝑥 ∈ V 𝜑) = (℩𝑥𝜑) | ||
Theorem | riotauni 7122 | Restricted iota in terms of class union. (Contributed by NM, 11-Oct-2011.) |
⊢ (∃!𝑥 ∈ 𝐴 𝜑 → (℩𝑥 ∈ 𝐴 𝜑) = ∪ {𝑥 ∈ 𝐴 ∣ 𝜑}) | ||
Theorem | nfriota1 7123* | The abstraction variable in a restricted iota descriptor isn't free. (Contributed by NM, 12-Oct-2011.) (Revised by Mario Carneiro, 15-Oct-2016.) |
⊢ Ⅎ𝑥(℩𝑥 ∈ 𝐴 𝜑) | ||
Theorem | nfriotadw 7124* | Deduction version of nfriota 7128 with a disjoint variable condition, which contrary to nfriotad 7127 does not require ax-13 2390. (Contributed by NM, 18-Feb-2013.) (Revised by Gino Giotto, 26-Jan-2024.) |
⊢ Ⅎ𝑦𝜑 & ⊢ (𝜑 → Ⅎ𝑥𝜓) & ⊢ (𝜑 → Ⅎ𝑥𝐴) ⇒ ⊢ (𝜑 → Ⅎ𝑥(℩𝑦 ∈ 𝐴 𝜓)) | ||
Theorem | cbvriotaw 7125* | Change bound variable in a restricted description binder. Version of cbvriota 7129 with a disjoint variable condition, which does not require ax-13 2390. (Contributed by NM, 18-Mar-2013.) (Revised by Gino Giotto, 26-Jan-2024.) |
⊢ Ⅎ𝑦𝜑 & ⊢ Ⅎ𝑥𝜓 & ⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓)) ⇒ ⊢ (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑦 ∈ 𝐴 𝜓) | ||
Theorem | cbvriotavw 7126* | Change bound variable in a restricted description binder. Version of cbvriotav 7130 with a disjoint variable condition, which does not require ax-13 2390. (Contributed by NM, 18-Mar-2013.) (Revised by Gino Giotto, 26-Jan-2024.) |
⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓)) ⇒ ⊢ (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑦 ∈ 𝐴 𝜓) | ||
Theorem | nfriotad 7127 | Deduction version of nfriota 7128. Usage of this theorem is discouraged because it depends on ax-13 2390. Use the weaker nfriotadw 7124 when possible. (Contributed by NM, 18-Feb-2013.) (Revised by Mario Carneiro, 15-Oct-2016.) (New usage is discouraged.) |
⊢ Ⅎ𝑦𝜑 & ⊢ (𝜑 → Ⅎ𝑥𝜓) & ⊢ (𝜑 → Ⅎ𝑥𝐴) ⇒ ⊢ (𝜑 → Ⅎ𝑥(℩𝑦 ∈ 𝐴 𝜓)) | ||
Theorem | nfriota 7128* | A variable not free in a wff remains so in a restricted iota descriptor. (Contributed by NM, 12-Oct-2011.) |
⊢ Ⅎ𝑥𝜑 & ⊢ Ⅎ𝑥𝐴 ⇒ ⊢ Ⅎ𝑥(℩𝑦 ∈ 𝐴 𝜑) | ||
Theorem | cbvriota 7129* | Change bound variable in a restricted description binder. Usage of this theorem is discouraged because it depends on ax-13 2390. Use the weaker cbvriotaw 7125 when possible. (Contributed by NM, 18-Mar-2013.) (Revised by Mario Carneiro, 15-Oct-2016.) (New usage is discouraged.) |
⊢ Ⅎ𝑦𝜑 & ⊢ Ⅎ𝑥𝜓 & ⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓)) ⇒ ⊢ (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑦 ∈ 𝐴 𝜓) | ||
Theorem | cbvriotav 7130* | Change bound variable in a restricted description binder. Usage of this theorem is discouraged because it depends on ax-13 2390. Use the weaker cbvriotavw 7126 when possible. (Contributed by NM, 18-Mar-2013.) (Revised by Mario Carneiro, 15-Oct-2016.) (New usage is discouraged.) |
⊢ (𝑥 = 𝑦 → (𝜑 ↔ 𝜓)) ⇒ ⊢ (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑦 ∈ 𝐴 𝜓) | ||
Theorem | csbriota 7131* | Interchange class substitution and restricted description binder. (Contributed by NM, 24-Feb-2013.) (Revised by NM, 2-Sep-2018.) |
⊢ ⦋𝐴 / 𝑥⦌(℩𝑦 ∈ 𝐵 𝜑) = (℩𝑦 ∈ 𝐵 [𝐴 / 𝑥]𝜑) | ||
Theorem | riotacl2 7132 | Membership law for "the unique element in 𝐴 such that 𝜑". (Contributed by NM, 21-Aug-2011.) (Revised by Mario Carneiro, 23-Dec-2016.) |
⊢ (∃!𝑥 ∈ 𝐴 𝜑 → (℩𝑥 ∈ 𝐴 𝜑) ∈ {𝑥 ∈ 𝐴 ∣ 𝜑}) | ||
Theorem | riotacl 7133* | Closure of restricted iota. (Contributed by NM, 21-Aug-2011.) |
⊢ (∃!𝑥 ∈ 𝐴 𝜑 → (℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐴) | ||
Theorem | riotasbc 7134 | Substitution law for descriptions. Compare iotasbc 40758. (Contributed by NM, 23-Aug-2011.) (Proof shortened by Mario Carneiro, 24-Dec-2016.) |
⊢ (∃!𝑥 ∈ 𝐴 𝜑 → [(℩𝑥 ∈ 𝐴 𝜑) / 𝑥]𝜑) | ||
Theorem | riotabidva 7135* | Equivalent wff's yield equal restricted class abstractions (deduction form). (rabbidva 3480 analog.) (Contributed by NM, 17-Jan-2012.) |
⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → (𝜓 ↔ 𝜒)) ⇒ ⊢ (𝜑 → (℩𝑥 ∈ 𝐴 𝜓) = (℩𝑥 ∈ 𝐴 𝜒)) | ||
Theorem | riotabiia 7136 | Equivalent wff's yield equal restricted iotas (inference form). (rabbiia 3474 analog.) (Contributed by NM, 16-Jan-2012.) |
⊢ (𝑥 ∈ 𝐴 → (𝜑 ↔ 𝜓)) ⇒ ⊢ (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑥 ∈ 𝐴 𝜓) | ||
Theorem | riota1 7137* | Property of restricted iota. Compare iota1 6334. (Contributed by Mario Carneiro, 15-Oct-2016.) |
⊢ (∃!𝑥 ∈ 𝐴 𝜑 → ((𝑥 ∈ 𝐴 ∧ 𝜑) ↔ (℩𝑥 ∈ 𝐴 𝜑) = 𝑥)) | ||
Theorem | riota1a 7138 | Property of iota. (Contributed by NM, 23-Aug-2011.) |
⊢ ((𝑥 ∈ 𝐴 ∧ ∃!𝑥 ∈ 𝐴 𝜑) → (𝜑 ↔ (℩𝑥(𝑥 ∈ 𝐴 ∧ 𝜑)) = 𝑥)) | ||
Theorem | riota2df 7139* | A deduction version of riota2f 7140. (Contributed by NM, 17-Feb-2013.) (Revised by Mario Carneiro, 15-Oct-2016.) |
⊢ Ⅎ𝑥𝜑 & ⊢ (𝜑 → Ⅎ𝑥𝐵) & ⊢ (𝜑 → Ⅎ𝑥𝜒) & ⊢ (𝜑 → 𝐵 ∈ 𝐴) & ⊢ ((𝜑 ∧ 𝑥 = 𝐵) → (𝜓 ↔ 𝜒)) ⇒ ⊢ ((𝜑 ∧ ∃!𝑥 ∈ 𝐴 𝜓) → (𝜒 ↔ (℩𝑥 ∈ 𝐴 𝜓) = 𝐵)) | ||
Theorem | riota2f 7140* | This theorem shows a condition that allows us to represent a descriptor with a class expression 𝐵. (Contributed by NM, 23-Aug-2011.) (Revised by Mario Carneiro, 15-Oct-2016.) |
⊢ Ⅎ𝑥𝐵 & ⊢ Ⅎ𝑥𝜓 & ⊢ (𝑥 = 𝐵 → (𝜑 ↔ 𝜓)) ⇒ ⊢ ((𝐵 ∈ 𝐴 ∧ ∃!𝑥 ∈ 𝐴 𝜑) → (𝜓 ↔ (℩𝑥 ∈ 𝐴 𝜑) = 𝐵)) | ||
Theorem | riota2 7141* | This theorem shows a condition that allows us to represent a descriptor with a class expression 𝐵. (Contributed by NM, 23-Aug-2011.) (Revised by Mario Carneiro, 10-Dec-2016.) |
⊢ (𝑥 = 𝐵 → (𝜑 ↔ 𝜓)) ⇒ ⊢ ((𝐵 ∈ 𝐴 ∧ ∃!𝑥 ∈ 𝐴 𝜑) → (𝜓 ↔ (℩𝑥 ∈ 𝐴 𝜑) = 𝐵)) | ||
Theorem | riotaeqimp 7142* | If two restricted iota descriptors for an equality are equal, then the terms of the equality are equal. (Contributed by AV, 6-Dec-2020.) |
⊢ 𝐼 = (℩𝑎 ∈ 𝑉 𝑋 = 𝐴) & ⊢ 𝐽 = (℩𝑎 ∈ 𝑉 𝑌 = 𝐴) & ⊢ (𝜑 → ∃!𝑎 ∈ 𝑉 𝑋 = 𝐴) & ⊢ (𝜑 → ∃!𝑎 ∈ 𝑉 𝑌 = 𝐴) ⇒ ⊢ ((𝜑 ∧ 𝐼 = 𝐽) → 𝑋 = 𝑌) | ||
Theorem | riotaprop 7143* | Properties of a restricted definite description operator. (Contributed by NM, 23-Nov-2013.) |
⊢ Ⅎ𝑥𝜓 & ⊢ 𝐵 = (℩𝑥 ∈ 𝐴 𝜑) & ⊢ (𝑥 = 𝐵 → (𝜑 ↔ 𝜓)) ⇒ ⊢ (∃!𝑥 ∈ 𝐴 𝜑 → (𝐵 ∈ 𝐴 ∧ 𝜓)) | ||
Theorem | riota5f 7144* | A method for computing restricted iota. (Contributed by NM, 16-Apr-2013.) (Revised by Mario Carneiro, 15-Oct-2016.) |
⊢ (𝜑 → Ⅎ𝑥𝐵) & ⊢ (𝜑 → 𝐵 ∈ 𝐴) & ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → (𝜓 ↔ 𝑥 = 𝐵)) ⇒ ⊢ (𝜑 → (℩𝑥 ∈ 𝐴 𝜓) = 𝐵) | ||
Theorem | riota5 7145* | A method for computing restricted iota. (Contributed by NM, 20-Oct-2011.) (Revised by Mario Carneiro, 6-Dec-2016.) |
⊢ (𝜑 → 𝐵 ∈ 𝐴) & ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → (𝜓 ↔ 𝑥 = 𝐵)) ⇒ ⊢ (𝜑 → (℩𝑥 ∈ 𝐴 𝜓) = 𝐵) | ||
Theorem | riotass2 7146* | Restriction of a unique element to a smaller class. (Contributed by NM, 21-Aug-2011.) (Revised by NM, 22-Mar-2013.) |
⊢ (((𝐴 ⊆ 𝐵 ∧ ∀𝑥 ∈ 𝐴 (𝜑 → 𝜓)) ∧ (∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜓)) → (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑥 ∈ 𝐵 𝜓)) | ||
Theorem | riotass 7147* | Restriction of a unique element to a smaller class. (Contributed by NM, 19-Oct-2005.) (Revised by Mario Carneiro, 24-Dec-2016.) |
⊢ ((𝐴 ⊆ 𝐵 ∧ ∃𝑥 ∈ 𝐴 𝜑 ∧ ∃!𝑥 ∈ 𝐵 𝜑) → (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑥 ∈ 𝐵 𝜑)) | ||
Theorem | moriotass 7148* | Restriction of a unique element to a smaller class. (Contributed by NM, 19-Feb-2006.) (Revised by NM, 16-Jun-2017.) |
⊢ ((𝐴 ⊆ 𝐵 ∧ ∃𝑥 ∈ 𝐴 𝜑 ∧ ∃*𝑥 ∈ 𝐵 𝜑) → (℩𝑥 ∈ 𝐴 𝜑) = (℩𝑥 ∈ 𝐵 𝜑)) | ||
Theorem | snriota 7149 | A restricted class abstraction with a unique member can be expressed as a singleton. (Contributed by NM, 30-May-2006.) |
⊢ (∃!𝑥 ∈ 𝐴 𝜑 → {𝑥 ∈ 𝐴 ∣ 𝜑} = {(℩𝑥 ∈ 𝐴 𝜑)}) | ||
Theorem | riotaxfrd 7150* | Change the variable 𝑥 in the expression for "the unique 𝑥 such that 𝜓 " to another variable 𝑦 contained in expression 𝐵. Use reuhypd 5322 to eliminate the last hypothesis. (Contributed by NM, 16-Jan-2012.) (Revised by Mario Carneiro, 15-Oct-2016.) |
⊢ Ⅎ𝑦𝐶 & ⊢ ((𝜑 ∧ 𝑦 ∈ 𝐴) → 𝐵 ∈ 𝐴) & ⊢ ((𝜑 ∧ (℩𝑦 ∈ 𝐴 𝜒) ∈ 𝐴) → 𝐶 ∈ 𝐴) & ⊢ (𝑥 = 𝐵 → (𝜓 ↔ 𝜒)) & ⊢ (𝑦 = (℩𝑦 ∈ 𝐴 𝜒) → 𝐵 = 𝐶) & ⊢ ((𝜑 ∧ 𝑥 ∈ 𝐴) → ∃!𝑦 ∈ 𝐴 𝑥 = 𝐵) ⇒ ⊢ ((𝜑 ∧ ∃!𝑥 ∈ 𝐴 𝜓) → (℩𝑥 ∈ 𝐴 𝜓) = 𝐶) | ||
Theorem | eusvobj2 7151* | Specify the same property in two ways when class 𝐵(𝑦) is single-valued. (Contributed by NM, 1-Nov-2010.) (Proof shortened by Mario Carneiro, 24-Dec-2016.) |
⊢ 𝐵 ∈ V ⇒ ⊢ (∃!𝑥∃𝑦 ∈ 𝐴 𝑥 = 𝐵 → (∃𝑦 ∈ 𝐴 𝑥 = 𝐵 ↔ ∀𝑦 ∈ 𝐴 𝑥 = 𝐵)) | ||
Theorem | eusvobj1 7152* | Specify the same object in two ways when class 𝐵(𝑦) is single-valued. (Contributed by NM, 1-Nov-2010.) (Proof shortened by Mario Carneiro, 19-Nov-2016.) |
⊢ 𝐵 ∈ V ⇒ ⊢ (∃!𝑥∃𝑦 ∈ 𝐴 𝑥 = 𝐵 → (℩𝑥∃𝑦 ∈ 𝐴 𝑥 = 𝐵) = (℩𝑥∀𝑦 ∈ 𝐴 𝑥 = 𝐵)) | ||
Theorem | f1ofveu 7153* | There is one domain element for each value of a one-to-one onto function. (Contributed by NM, 26-May-2006.) |
⊢ ((𝐹:𝐴–1-1-onto→𝐵 ∧ 𝐶 ∈ 𝐵) → ∃!𝑥 ∈ 𝐴 (𝐹‘𝑥) = 𝐶) | ||
Theorem | f1ocnvfv3 7154* | Value of the converse of a one-to-one onto function. (Contributed by NM, 26-May-2006.) (Proof shortened by Mario Carneiro, 24-Dec-2016.) |
⊢ ((𝐹:𝐴–1-1-onto→𝐵 ∧ 𝐶 ∈ 𝐵) → (◡𝐹‘𝐶) = (℩𝑥 ∈ 𝐴 (𝐹‘𝑥) = 𝐶)) | ||
Theorem | riotaund 7155* | Restricted iota equals the empty set when not meaningful. (Contributed by NM, 16-Jan-2012.) (Revised by Mario Carneiro, 15-Oct-2016.) (Revised by NM, 13-Sep-2018.) |
⊢ (¬ ∃!𝑥 ∈ 𝐴 𝜑 → (℩𝑥 ∈ 𝐴 𝜑) = ∅) | ||
Theorem | riotassuni 7156* | The restricted iota class is limited in size by the base set. (Contributed by Mario Carneiro, 24-Dec-2016.) |
⊢ (℩𝑥 ∈ 𝐴 𝜑) ⊆ (𝒫 ∪ 𝐴 ∪ ∪ 𝐴) | ||
Theorem | riotaclb 7157* | Bidirectional closure of restricted iota when domain is not empty. (Contributed by NM, 28-Feb-2013.) (Revised by Mario Carneiro, 24-Dec-2016.) (Revised by NM, 13-Sep-2018.) |
⊢ (¬ ∅ ∈ 𝐴 → (∃!𝑥 ∈ 𝐴 𝜑 ↔ (℩𝑥 ∈ 𝐴 𝜑) ∈ 𝐴)) | ||
Syntax | co 7158 | Extend class notation to include the value of an operation 𝐹 (such as +) for two arguments 𝐴 and 𝐵. Note that the syntax is simply three class symbols in a row surrounded by parentheses. Since operation values are the only possible class expressions consisting of three class expressions in a row surrounded by parentheses, the syntax is unambiguous. (For an example of how syntax could become ambiguous if we are not careful, see the comment in cneg 10873.) |
class (𝐴𝐹𝐵) | ||
Syntax | coprab 7159 | Extend class notation to include class abstraction (class builder) of nested ordered pairs. |
class {〈〈𝑥, 𝑦〉, 𝑧〉 ∣ 𝜑} | ||
Syntax | cmpo 7160 | Extend the definition of a class to include maps-to notation for defining an operation via a rule. |
class (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝐶) | ||
Definition | df-ov 7161 | Define the value of an operation. Definition of operation value in [Enderton] p. 79. Note that the syntax is simply three class expressions in a row bracketed by parentheses. There are no restrictions of any kind on what those class expressions may be, although only certain kinds of class expressions - a binary operation 𝐹 and its arguments 𝐴 and 𝐵- will be useful for proving meaningful theorems. For example, if class 𝐹 is the operation + and arguments 𝐴 and 𝐵 are 3 and 2, the expression (3 + 2) can be proved to equal 5 (see 3p2e5 11791). This definition is well-defined, although not very meaningful, when classes 𝐴 and/or 𝐵 are proper classes (i.e. are not sets); see ovprc1 7197 and ovprc2 7198. On the other hand, we often find uses for this definition when 𝐹 is a proper class, such as +o in oav 8138. 𝐹 is normally equal to a class of nested ordered pairs of the form defined by df-oprab 7162. (Contributed by NM, 28-Feb-1995.) |
⊢ (𝐴𝐹𝐵) = (𝐹‘〈𝐴, 𝐵〉) | ||
Definition | df-oprab 7162* | Define the class abstraction (class builder) of a collection of nested ordered pairs (for use in defining operations). This is a special case of Definition 4.16 of [TakeutiZaring] p. 14. Normally 𝑥, 𝑦, and 𝑧 are distinct, although the definition doesn't strictly require it. See df-ov 7161 for the value of an operation. The brace notation is called "class abstraction" by Quine; it is also called a "class builder" in the literature. The value of the most common operation class builder is given by ovmpo 7312. (Contributed by NM, 12-Mar-1995.) |
⊢ {〈〈𝑥, 𝑦〉, 𝑧〉 ∣ 𝜑} = {𝑤 ∣ ∃𝑥∃𝑦∃𝑧(𝑤 = 〈〈𝑥, 𝑦〉, 𝑧〉 ∧ 𝜑)} | ||
Definition | df-mpo 7163* | Define maps-to notation for defining an operation via a rule. Read as "the operation defined by the map from 𝑥, 𝑦 (in 𝐴 × 𝐵) to 𝐶(𝑥, 𝑦)". An extension of df-mpt 5149 for two arguments. (Contributed by NM, 17-Feb-2008.) |
⊢ (𝑥 ∈ 𝐴, 𝑦 ∈ 𝐵 ↦ 𝐶) = {〈〈𝑥, 𝑦〉, 𝑧〉 ∣ ((𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵) ∧ 𝑧 = 𝐶)} | ||
Theorem | oveq 7164 | Equality theorem for operation value. (Contributed by NM, 28-Feb-1995.) |
⊢ (𝐹 = 𝐺 → (𝐴𝐹𝐵) = (𝐴𝐺𝐵)) | ||
Theorem | oveq1 7165 | Equality theorem for operation value. (Contributed by NM, 28-Feb-1995.) |
⊢ (𝐴 = 𝐵 → (𝐴𝐹𝐶) = (𝐵𝐹𝐶)) | ||
Theorem | oveq2 7166 | Equality theorem for operation value. (Contributed by NM, 28-Feb-1995.) |
⊢ (𝐴 = 𝐵 → (𝐶𝐹𝐴) = (𝐶𝐹𝐵)) | ||
Theorem | oveq12 7167 | Equality theorem for operation value. (Contributed by NM, 16-Jul-1995.) |
⊢ ((𝐴 = 𝐵 ∧ 𝐶 = 𝐷) → (𝐴𝐹𝐶) = (𝐵𝐹𝐷)) | ||
Theorem | oveq1i 7168 | Equality inference for operation value. (Contributed by NM, 28-Feb-1995.) |
⊢ 𝐴 = 𝐵 ⇒ ⊢ (𝐴𝐹𝐶) = (𝐵𝐹𝐶) | ||
Theorem | oveq2i 7169 | Equality inference for operation value. (Contributed by NM, 28-Feb-1995.) |
⊢ 𝐴 = 𝐵 ⇒ ⊢ (𝐶𝐹𝐴) = (𝐶𝐹𝐵) | ||
Theorem | oveq12i 7170 | Equality inference for operation value. (Contributed by NM, 28-Feb-1995.) (Proof shortened by Andrew Salmon, 22-Oct-2011.) |
⊢ 𝐴 = 𝐵 & ⊢ 𝐶 = 𝐷 ⇒ ⊢ (𝐴𝐹𝐶) = (𝐵𝐹𝐷) | ||
Theorem | oveqi 7171 | Equality inference for operation value. (Contributed by NM, 24-Nov-2007.) |
⊢ 𝐴 = 𝐵 ⇒ ⊢ (𝐶𝐴𝐷) = (𝐶𝐵𝐷) | ||
Theorem | oveq123i 7172 | Equality inference for operation value. (Contributed by FL, 11-Jul-2010.) |
⊢ 𝐴 = 𝐶 & ⊢ 𝐵 = 𝐷 & ⊢ 𝐹 = 𝐺 ⇒ ⊢ (𝐴𝐹𝐵) = (𝐶𝐺𝐷) | ||
Theorem | oveq1d 7173 | Equality deduction for operation value. (Contributed by NM, 13-Mar-1995.) |
⊢ (𝜑 → 𝐴 = 𝐵) ⇒ ⊢ (𝜑 → (𝐴𝐹𝐶) = (𝐵𝐹𝐶)) | ||
Theorem | oveq2d 7174 | Equality deduction for operation value. (Contributed by NM, 13-Mar-1995.) |
⊢ (𝜑 → 𝐴 = 𝐵) ⇒ ⊢ (𝜑 → (𝐶𝐹𝐴) = (𝐶𝐹𝐵)) | ||
Theorem | oveqd 7175 | Equality deduction for operation value. (Contributed by NM, 9-Sep-2006.) |
⊢ (𝜑 → 𝐴 = 𝐵) ⇒ ⊢ (𝜑 → (𝐶𝐴𝐷) = (𝐶𝐵𝐷)) | ||
Theorem | oveq12d 7176 | Equality deduction for operation value. (Contributed by NM, 13-Mar-1995.) (Proof shortened by Andrew Salmon, 22-Oct-2011.) |
⊢ (𝜑 → 𝐴 = 𝐵) & ⊢ (𝜑 → 𝐶 = 𝐷) ⇒ ⊢ (𝜑 → (𝐴𝐹𝐶) = (𝐵𝐹𝐷)) | ||
Theorem | oveqan12d 7177 | Equality deduction for operation value. (Contributed by NM, 10-Aug-1995.) |
⊢ (𝜑 → 𝐴 = 𝐵) & ⊢ (𝜓 → 𝐶 = 𝐷) ⇒ ⊢ ((𝜑 ∧ 𝜓) → (𝐴𝐹𝐶) = (𝐵𝐹𝐷)) | ||
Theorem | oveqan12rd 7178 | Equality deduction for operation value. (Contributed by NM, 10-Aug-1995.) |
⊢ (𝜑 → 𝐴 = 𝐵) & ⊢ (𝜓 → 𝐶 = 𝐷) ⇒ ⊢ ((𝜓 ∧ 𝜑) → (𝐴𝐹𝐶) = (𝐵𝐹𝐷)) | ||
Theorem | oveq123d 7179 | Equality deduction for operation value. (Contributed by FL, 22-Dec-2008.) |
⊢ (𝜑 → 𝐹 = 𝐺) & ⊢ (𝜑 → 𝐴 = 𝐵) & ⊢ (𝜑 → 𝐶 = 𝐷) ⇒ ⊢ (𝜑 → (𝐴𝐹𝐶) = (𝐵𝐺𝐷)) | ||
Theorem | fvoveq1d 7180 | Equality deduction for nested function and operation value. (Contributed by AV, 23-Jul-2022.) |
⊢ (𝜑 → 𝐴 = 𝐵) ⇒ ⊢ (𝜑 → (𝐹‘(𝐴𝑂𝐶)) = (𝐹‘(𝐵𝑂𝐶))) | ||
Theorem | fvoveq1 7181 | Equality theorem for nested function and operation value. Closed form of fvoveq1d 7180. (Contributed by AV, 23-Jul-2022.) |
⊢ (𝐴 = 𝐵 → (𝐹‘(𝐴𝑂𝐶)) = (𝐹‘(𝐵𝑂𝐶))) | ||
Theorem | ovanraleqv 7182* | Equality theorem for a conjunction with an operation values within a restricted universal quantification. Technical theorem to be used to reduce the size of a significant number of proofs. (Contributed by AV, 13-Aug-2022.) |
⊢ (𝐵 = 𝑋 → (𝜑 ↔ 𝜓)) ⇒ ⊢ (𝐵 = 𝑋 → (∀𝑥 ∈ 𝑉 (𝜑 ∧ (𝐴 · 𝐵) = 𝐶) ↔ ∀𝑥 ∈ 𝑉 (𝜓 ∧ (𝐴 · 𝑋) = 𝐶))) | ||
Theorem | imbrov2fvoveq 7183 | Equality theorem for nested function and operation value in an implication for a binary relation. Technical theorem to be used to reduce the size of a significant number of proofs. (Contributed by AV, 17-Aug-2022.) |
⊢ (𝑋 = 𝑌 → (𝜑 ↔ 𝜓)) ⇒ ⊢ (𝑋 = 𝑌 → ((𝜑 → (𝐹‘((𝐺‘𝑋) · 𝑂))𝑅𝐴) ↔ (𝜓 → (𝐹‘((𝐺‘𝑌) · 𝑂))𝑅𝐴))) | ||
Theorem | ovrspc2v 7184* | If an operation value is element of a class for all operands of two classes, then the operation value is an element of the class for specific operands of the two classes. (Contributed by Mario Carneiro, 6-Dec-2014.) |
⊢ (((𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐵) ∧ ∀𝑥 ∈ 𝐴 ∀𝑦 ∈ 𝐵 (𝑥𝐹𝑦) ∈ 𝐶) → (𝑋𝐹𝑌) ∈ 𝐶) | ||
Theorem | oveqrspc2v 7185* | Restricted specialization of operands, using implicit substitution. (Contributed by Mario Carneiro, 6-Dec-2014.) |
⊢ ((𝜑 ∧ (𝑥 ∈ 𝐴 ∧ 𝑦 ∈ 𝐵)) → (𝑥𝐹𝑦) = (𝑥𝐺𝑦)) ⇒ ⊢ ((𝜑 ∧ (𝑋 ∈ 𝐴 ∧ 𝑌 ∈ 𝐵)) → (𝑋𝐹𝑌) = (𝑋𝐺𝑌)) | ||
Theorem | oveqdr 7186 | Equality of two operations for any two operands. Useful in proofs using *propd theorems. (Contributed by Mario Carneiro, 29-Jun-2015.) |
⊢ (𝜑 → 𝐹 = 𝐺) ⇒ ⊢ ((𝜑 ∧ 𝜓) → (𝑥𝐹𝑦) = (𝑥𝐺𝑦)) | ||
Theorem | nfovd 7187 | Deduction version of bound-variable hypothesis builder nfov 7188. (Contributed by NM, 13-Dec-2005.) (Proof shortened by Andrew Salmon, 22-Oct-2011.) |
⊢ (𝜑 → Ⅎ𝑥𝐴) & ⊢ (𝜑 → Ⅎ𝑥𝐹) & ⊢ (𝜑 → Ⅎ𝑥𝐵) ⇒ ⊢ (𝜑 → Ⅎ𝑥(𝐴𝐹𝐵)) | ||
Theorem | nfov 7188 | Bound-variable hypothesis builder for operation value. (Contributed by NM, 4-May-2004.) |
⊢ Ⅎ𝑥𝐴 & ⊢ Ⅎ𝑥𝐹 & ⊢ Ⅎ𝑥𝐵 ⇒ ⊢ Ⅎ𝑥(𝐴𝐹𝐵) | ||
Theorem | oprabidw 7189* | The law of concretion. Special case of Theorem 9.5 of [Quine] p. 61. Version of oprabid 7190 with a disjoint variable condition, which does not require ax-13 2390. (Contributed by Mario Carneiro, 20-Mar-2013.) (Revised by Gino Giotto, 26-Jan-2024.) |
⊢ (〈〈𝑥, 𝑦〉, 𝑧〉 ∈ {〈〈𝑥, 𝑦〉, 𝑧〉 ∣ 𝜑} ↔ 𝜑) | ||
Theorem | oprabid 7190 | The law of concretion. Special case of Theorem 9.5 of [Quine] p. 61. Usage of this theorem is discouraged because it depends on ax-13 2390. Use the weaker oprabidw 7189 when possible. (Contributed by Mario Carneiro, 20-Mar-2013.) (New usage is discouraged.) |
⊢ (〈〈𝑥, 𝑦〉, 𝑧〉 ∈ {〈〈𝑥, 𝑦〉, 𝑧〉 ∣ 𝜑} ↔ 𝜑) | ||
Theorem | ovex 7191 | The result of an operation is a set. (Contributed by NM, 13-Mar-1995.) |
⊢ (𝐴𝐹𝐵) ∈ V | ||
Theorem | ovexi 7192 | The result of an operation is a set. (Contributed by Glauco Siliprandi, 26-Jun-2021.) |
⊢ 𝐴 = (𝐵𝐹𝐶) ⇒ ⊢ 𝐴 ∈ V | ||
Theorem | ovexd 7193 | The result of an operation is a set. (Contributed by Glauco Siliprandi, 23-Oct-2021.) |
⊢ (𝜑 → (𝐴𝐹𝐵) ∈ V) | ||
Theorem | ovssunirn 7194 | The result of an operation value is always a subset of the union of the range. (Contributed by Mario Carneiro, 12-Jan-2017.) |
⊢ (𝑋𝐹𝑌) ⊆ ∪ ran 𝐹 | ||
Theorem | 0ov 7195 | Operation value of the empty set. (Contributed by AV, 15-May-2021.) |
⊢ (𝐴∅𝐵) = ∅ | ||
Theorem | ovprc 7196 | The value of an operation when the one of the arguments is a proper class. Note: this theorem is dependent on our particular definitions of operation value, function value, and ordered pair. (Contributed by Mario Carneiro, 26-Apr-2015.) |
⊢ Rel dom 𝐹 ⇒ ⊢ (¬ (𝐴 ∈ V ∧ 𝐵 ∈ V) → (𝐴𝐹𝐵) = ∅) | ||
Theorem | ovprc1 7197 | The value of an operation when the first argument is a proper class. (Contributed by NM, 16-Jun-2004.) |
⊢ Rel dom 𝐹 ⇒ ⊢ (¬ 𝐴 ∈ V → (𝐴𝐹𝐵) = ∅) | ||
Theorem | ovprc2 7198 | The value of an operation when the second argument is a proper class. (Contributed by Mario Carneiro, 26-Apr-2015.) |
⊢ Rel dom 𝐹 ⇒ ⊢ (¬ 𝐵 ∈ V → (𝐴𝐹𝐵) = ∅) | ||
Theorem | ovrcl 7199 | Reverse closure for an operation value. (Contributed by Mario Carneiro, 5-May-2015.) |
⊢ Rel dom 𝐹 ⇒ ⊢ (𝐶 ∈ (𝐴𝐹𝐵) → (𝐴 ∈ V ∧ 𝐵 ∈ V)) | ||
Theorem | csbov123 7200 | Move class substitution in and out of an operation. (Contributed by NM, 12-Nov-2005.) (Revised by NM, 23-Aug-2018.) |
⊢ ⦋𝐴 / 𝑥⦌(𝐵𝐹𝐶) = (⦋𝐴 / 𝑥⦌𝐵⦋𝐴 / 𝑥⦌𝐹⦋𝐴 / 𝑥⦌𝐶) |
< Previous Next > |
Copyright terms: Public domain | < Previous Next > |