physics, language, maths & music

Physics, Language, Maths & Music(partly in arXiv:1204.3458)

Bob Coecke, Oxford, CS-Quantum

SyFest, Vienna, July 2013

=

f

f =

f f

f

ALICE

BOB

=

ALICE

BOB

f=

not

likeBobAlice

does

Alice not like

not

Bob

meaning vectors of words

pregroup grammar

. . . via (some sort of) Logic(partly in arXiv:1204.3458)

Bob Coecke, Oxford, CS-Quantum

SyFest, Vienna, July 2013

=

f

f =

f f

f

ALICE

BOB

=

ALICE

BOB

f=

not

likeBobAlice

does

Alice not like

not

Bob

meaning vectors of words

pregroup grammar

— PHYSICS —

Samson Abramsky & BC (2004) A categorical semantics for quantum proto-cols. In: IEEE-LiCS’04. quant-ph/0402130

BC (2005) Kindergarten quantum mechanics. quant-ph/0510032

— genesis —

[von Neumann 1932] Formalized quantum mechanicsin “Mathematische Grundlagen der Quantenmechanik”

— genesis —

[von Neumann 1932] Formalized quantum mechanicsin “Mathematische Grundlagen der Quantenmechanik”

[von Neumann to Birkhoff 1935] “I would like tomake a confession which may seem immoral: I do notbelieve absolutely in Hilbert space no more.” (sic)

— genesis —

[von Neumann 1932] Formalized quantum mechanicsin “Mathematische Grundlagen der Quantenmechanik”

[von Neumann to Birkhoff 1935] “I would like tomake a confession which may seem immoral: I do notbelieve absolutely in Hilbert space no more.” (sic)

[Birkhoff and von Neumann 1936] The Logic of Quan-tum Mechanics in Annals of Mathematics.

— genesis —

[von Neumann 1932] Formalized quantum mechanicsin “Mathematische Grundlagen der Quantenmechanik”

[von Neumann to Birkhoff 1935] “I would like tomake a confession which may seem immoral: I do notbelieve absolutely in Hilbert space no more.” (sic)

[Birkhoff and von Neumann 1936] The Logic of Quan-tum Mechanics in Annals of Mathematics.

[1936 – 2000] many followed them, ... and FAILED.

— genesis —

[von Neumann 1932] Formalized quantum mechanicsin “Mathematische Grundlagen der Quantenmechanik”

[von Neumann to Birkhoff 1935] “I would like tomake a confession which may seem immoral: I do notbelieve absolutely in Hilbert space no more.” (sic)

[Birkhoff and von Neumann 1936] The Logic of Quan-tum Mechanics in Annals of Mathematics.

[1936 – 2000] many followed them, ... and FAILED.

— the mathematics of it —

— the mathematics of it —

Hilbert space stuff: continuum, field structure of com-plex numbers, vector space over it, inner-product, etc.

— the mathematics of it —

Hilbert space stuff: continuum, field structure of com-plex numbers, vector space over it, inner-product, etc.

WHY?

— the mathematics of it —

Hilbert space stuff: continuum, field structure of com-plex numbers, vector space over it, inner-product, etc.

WHY?

von Neumann: only used it since it was ‘available’.

— the physics of it —

— the physics of it —

von Neumann crafted Birkhoff-von Neumann Quan-tum ‘Logic’ to capture the concept of superposition.

— the physics of it —

von Neumann crafted Birkhoff-von Neumann Quan-tum ‘Logic’ to capture the concept of superposition.

Schrodinger (1935): the stuff which is the true soul ofquantum theory is how quantum systems compose.

— the physics of it —

von Neumann crafted Birkhoff-von Neumann Quan-tum ‘Logic’ to capture the concept of superposition.

Schrodinger (1935): the stuff which is the true soul ofquantum theory is how quantum systems compose.

Quantum Computer Scientists: Schrodinger is right!

— the game plan —

— the game plan —

Task 0. Solve:tensor product structure

the other stuff= ???

— the game plan —

Task 0. Solve:tensor product structure

the other stuff= ???

i.e. axiomatize “⊗” without reference to spaces.

— the game plan —

Task 0. Solve:tensor product structure

the other stuff= ???

i.e. axiomatize “⊗” without reference to spaces.

Task 1. Investigate which assumptions (i.e. which struc-ture) on ⊗ is needed to deduce physical phenomena.

— the game plan —

Task 0. Solve:tensor product structure

the other stuff= ???

i.e. axiomatize “⊗” without reference to spaces.

Task 1. Investigate which assumptions (i.e. which struc-ture) on ⊗ is needed to deduce physical phenomena.

Task 2. Investigate wether such an “interaction struc-ture” appear elsewhere in “our classical reality”.

— wire and box language —

— wire and box language —

foutput wire(s)

input wire(s)Box =:

Interpretation: wire := system ; box := process

— wire and box language —

foutput wire(s)

input wire(s)Box =:

Interpretation: wire := system ; box := process

one system: n subsystems: no system:

︸︷︷︸1

. . .︸ ︷︷ ︸

n︸︷︷︸

0

— wire and box games —

sequential or causal or connected composition:

g ◦ f ≡g

f

parallel or acausal or disconnected composition:

f ⊗ g ≡ f fg

— merely a new notation? —

(g ◦ f ) ⊗ (k ◦ h) = (g ⊗ k) ◦ ( f ⊗ h)

=f h

g k

f h

g k

— quantitative metric —

f : A→ B

f

A

B

— quantitative metric —

f † : B→ A

f

B

A

— asserting (pure) entanglement —

quantumclassical

=

==

— asserting (pure) entanglement —

quantumclassical

=

==

⇒ introduce ‘parallel wire’ between systems:

subject to: only topology matters!

— quantum-like —

E.g.

=

Transpose:

ff

=Conjugate:

ff

=

classical data flow?

f

=

fff

classical data flow?

f

=

f

classical data flow?

f

=

f

classical data flow?

f

ALICE

BOB

=

ALICE

BOB

f

⇒ quantum teleportation

— symbolically: dagger compact categories —

Thm. [Kelly-Laplaza ’80; Selinger ’05] An equa-tional statement between expressions in dagger com-pact categorical language holds if and only if it isderivable in the graphical notation via homotopy.

Thm. [Hasegawa-Hofmann-Plotkin; Selinger ’08]An equational statement between expressions in dag-ger compact categorical language holds if and onlyif it is derivable in the dagger compact category of fi-nite dimensional Hilbert spaces, linear maps, tensorproduct and adjoints.

— LANGUAGE—

BC, Mehrnoosh Sadrzadeh & Stephen Clark (2010) Mathematical foundationsfor a compositional distributional model of meaning. arXiv:1003.4394

— the logic of it —

WHAT IS “LOGIC”?

— the logic of it —

WHAT IS “LOGIC”?

Pragmatic option 1: Logic is structure in language.

— the logic of it —

WHAT IS “LOGIC”?

Pragmatic option 1: Logic is structure in language.

“Alice and Bob ate everything or nothing, then got sick.”

connectives (∧,∨) : and, ornegation (¬) : not (cf. nothing = not something)entailment (⇒) : thenquantifiers (∀,∃) : every(thing), some(thing)constants (a, b) : thingvariable (x) : Alice, Bobpredicates (P(x),R(x, y)) : eating, getting sicktruth valuation (0, 1) : true, false

(∀z : Eat(a, z) ∧ Eat(b, z)) ∧ ¬(∃z : Eat(a, z) ∧ Eat(b, z))⇒ S ick(a), S ick(b)

— the logic of it —

WHAT IS “LOGIC”?

Pragmatic option 1: Logic is structure in language.

Pragmatic option 2: Logic lets machines reason.

— the logic of it —

WHAT IS “LOGIC”?

Pragmatic option 1: Logic is structure in language.

Pragmatic option 2: Logic lets machines reason.

E.g. automated theory exploration, ...

— the logic of it —

WHAT IS “LOGIC”?

Pragmatic option 1: Logic is structure in language.

Pragmatic option 2: Logic lets machines reason.

Our framework appeals to both senses of logic, andmoreover induces important new applications:From truth to meaning in natural language processing:

— (December 2010)

Automated theorem generation for graphical theories:

— http://sites.google.com/site/quantomatic/

— the from-words-to-a-sentence process —

Consider meanings of words, e.g. as vectors (cf. Google):

word 1 word 2 word n...

— the from-words-to-a-sentence process —

What is the meaning the sentence made up of these?

word 1 word 2 word n...

— the from-words-to-a-sentence process —

I.e. how do we/machines produce meanings of sentences?

word 1 word 2 word n...?

— the from-words-to-a-sentence process —

I.e. how do we/machines produce meanings of sentences?

word 1 word 2 word n...grammar

— the from-words-to-a-sentence process —

Information flow within a verb:

verb

object subject

— the from-words-to-a-sentence process —

Information flow within a verb:

verb

object subject

Again we have:

=

— pregoup grammar —

Lambek’s residuated monoids (1950’s):b ≤ a( c⇔ a · b ≤ c⇔ a ≤ c � b

— pregoup grammar —

Lambek’s residuated monoids (1950’s):b ≤ a( c⇔ a · b ≤ c⇔ a ≤ c � b

or equivalently,

a · (a( c) ≤ c ≤ a( (a · c)

(c � b) · b ≤ c ≤ (c · b) � b

— pregoup grammar —

Lambek’s residuated monoids (1950’s):b ≤ a( c⇔ a · b ≤ c⇔ a ≤ c � b

or equivalently,

a · (a( c) ≤ c ≤ a( (a · c)

(c � b) · b ≤ c ≤ (c · b) � b

Lambek’s pregroups (2000’s):a · ∗a ≤ 1 ≤ ∗a · ab∗ · b ≤ 1 ≤ b · b∗

— pregoup grammar —

Lambek’s residuated monoids (1950’s):b ≤ a( c⇔ a · b ≤ c⇔ a ≤ c � b

or equivalently,

a · (a( c) ≤ c ≤ a( (a · c)

(c � b) · b ≤ c ≤ (c · b) � b

Lambek’s pregroups (2000’s):a · −1a ≤ 1 ≤ −1a · a

b−1 · b ≤ 1 ≤ b · b−1

— pregoup grammar —

A A A AA A A A

-1

-1

-1

-1

=

A

A

A

A=A

A A

A=A

A

A

A=A

A A

A-1

-1

-1

-1 -1

-1 -1

-1

— pregoup grammar —

For noun type n, verb type is −1n · s · n−1, so:

— pregoup grammar —

For noun type n, verb type is −1n · s · n−1, so:

n · −1n · s · n−1 · n ≤ 1 · s · 1 ≤ s

— pregoup grammar —

For noun type n, verb type is −1n · s · n−1, so:

n · −1n · s · n−1 · n ≤ 1 · s · 1 ≤ s

— pregoup grammar —

For noun type n, verb type is −1n · s · n−1, so:

n · −1n · s · n−1 · n ≤ 1 · s · 1 ≤ s

— pregoup grammar —

For noun type n, verb type is −1n · s · n−1, so:

n · −1n · s · n−1 · n ≤ 1 · s · 1 ≤ s

Diagrammatic type reduction:

n nsn n-1 -1

— pregoup grammar —

For noun type n, verb type is −1n · s · n−1, so:

n · −1n · s · n−1 · n ≤ 1 · s · 1 ≤ s

Diagrammatic meaning:

verbn n

flow flow

— algorithm for meaning of sentences —

— algorithm for meaning of sentences —

1. Perform type reduction:

(word type 1) . . . (word type n) { sentence type

— algorithm for meaning of sentences —

1. Perform type reduction:

(word type 1) . . . (word type n) { sentence type

2. Interpret diagrammatic type reduction as linear map:

f :: 7→

∑i

〈ii|

⊗ id ⊗

∑i

〈ii|

— algorithm for meaning of sentences —

1. Perform type reduction:

(word type 1) . . . (word type n) { sentence type

2. Interpret diagrammatic type reduction as linear map:

f :: 7→

∑i

〈ii|

⊗ id ⊗

∑i

〈ii|

3. Apply this map to tensor of word meaning vectors:

f(−→v 1 ⊗ . . . ⊗

−→v n

)

—−−−−→Alice ⊗

−−−→does ⊗ −−→not ⊗

−−→like ⊗

−−→Bob —

—−−−−→Alice ⊗

−−−→does ⊗ −−→not ⊗

−−→like ⊗

−−→Bob —

Alice not like Bob

meaning vectors of words

not

grammar

does

—−−−−→Alice ⊗

−−−→does ⊗ −−→not ⊗

−−→like ⊗

−−→Bob —

Alice like Bob

meaning vectors of words

grammar

not

—−−−−→Alice ⊗

−−−→does ⊗ −−→not ⊗

−−→like ⊗

−−→Bob —

Alice like Bob

meaning vectors of words

grammar

not

—−−−−→Alice ⊗

−−−→does ⊗ −−→not ⊗

−−→like ⊗

−−→Bob —

Alice like Bob

meaning vectors of words

grammar

not= not

like

BobAlice

—−−−−→Alice ⊗

−−−→does ⊗ −−→not ⊗

−−→like ⊗

−−→Bob —

Alice like Bob

meaning vectors of words

grammar

not= not

like

BobAlice = not

likeBobAlice

Using: =

likelike

=

likelike

— experiment: word disambiguation —E.g. what is “saw”’ in: “Alice saw Bob with a saw”.

Edward Grefenstette & Mehrnoosh Sadrzadeh (2011) Experimental supportfor a categorical compositional distributional model of meaning. Acceptedfor: Empirical Methods in Natural Language Processing (EMNLP’11).

— Frobenius algebras —

— Frobenius algebras —

‘spiders’ =

m︷ ︸︸ ︷....

....︸ ︷︷ ︸n

such that, for k > 0:

m+m′−k︷ ︸︸ ︷........

....

....

....

︸ ︷︷ ︸n+n′−k

=

....

....

BC & Dusko Pavlovic (2007) Quantum measurement without sums. In: Math-ematics of Quantum Computing and Technology. quant-ph/0608035

BC, Dusko Pavlovic & Jamie Vicary (2008) A new description of orthogonalbases. Mathematical Structures in Computer Science. 0810.0812

— Frobenius algebras —

‘spiders’ =

m︷ ︸︸ ︷....

....︸ ︷︷ ︸n

such that, for k > 0:

m+m′−k︷ ︸︸ ︷........

....

....

....

︸ ︷︷ ︸n+n′−k

=

....

....

BC & Dusko Pavlovic (2007) Quantum measurement without sums. In: Math-ematics of Quantum Computing and Technology. quant-ph/0608035

BC, Dusko Pavlovic & Jamie Vicary (2008) A new description of orthogonalbases. Mathematical Structures in Computer Science. 0810.0812

— Frobenius algebras —Language-meaning:

Bob = (the) man who Alice hates = Bob

Stephen Clark, BC and Mehrnoosh Sadrzadeh (2013) The Frobenius Anatomyof Relative Pronouns. MOL ’13.

— Frobenius algebras —Language-meaning:

Bob = (the) man who Alice hates = Bob

Stephen Clark, BC and Mehrnoosh Sadrzadeh (2013) The Frobenius Anatomyof Relative Pronouns. MOL ’13.

— Frobenius algebras —Language-meaning:

Bob = (the) man who Alice hates = Bob

Stephen Clark, BC and Mehrnoosh Sadrzadeh (2013) The Frobenius Anatomyof Relative Pronouns. MOL ’13.

— MATHS —

— MATHS —

“Topological” QFT (Atiyah ’88):

F :: 7→ f : V ⊗ V → V

— MATHS —

“Topological” QFT (Atiyah ’88):

F :: 7→ f : V ⊗ V → V

“Grammatical” QFT:

F :: 7→

∑i

〈ii|

⊗id⊗

∑i

〈ii|

— MUSIC —

— MUSIC —