Majorization and Entanglement transformations

113

Transcript of Majorization and Entanglement transformations

Page 1: Majorization and Entanglement transformations

Majorization and Entanglement transformations

Gustavo Martín Bosyk

Instituto de Física La Plata, UNLP, CONICET, La Plata, Argentina

Università degli studi di Cagliari, Cagliari, Italia

In collaboration with:GMB, G. Sergioli, H. Freytes, F. Holik and G. Bellomo, arXiv:1608.04818v1 [quant-ph] (2016)

November 3, 2016

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 1 / 21

Page 2: Majorization and Entanglement transformations

Part I

Majorization

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Page 3: Majorization and Entanglement transformations

Situation A Situation B

Which situation has less uncertainty?

Game 1: what color is the ball? → A

Game 2: what color is NOT the ball? → B

How to compare probability vectors

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 3 / 21

Page 4: Majorization and Entanglement transformations

Situation A

Situation B

Which situation has less uncertainty?

Game 1: what color is the ball? → A

Game 2: what color is NOT the ball? → B

How to compare probability vectors

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 3 / 21

Page 5: Majorization and Entanglement transformations

Situation A Situation B

Which situation has less uncertainty?

Game 1: what color is the ball? → A

Game 2: what color is NOT the ball? → B

How to compare probability vectors

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 3 / 21

Page 6: Majorization and Entanglement transformations

Situation A Situation B

Which situation has less uncertainty?

Game 1: what color is the ball? → A

Game 2: what color is NOT the ball? → B

How to compare probability vectors

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 3 / 21

Page 7: Majorization and Entanglement transformations

Situation A Situation B

Which situation has less uncertainty?

Game 1: what color is the ball? → A

Game 2: what color is NOT the ball? → B

How to compare probability vectors

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 3 / 21

Page 8: Majorization and Entanglement transformations

Situation A Situation B

Which situation has less uncertainty?

Game 1: what color is the ball? → A

Game 2: what color is NOT the ball? → B

How to compare probability vectors

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 3 / 21

Page 9: Majorization and Entanglement transformations

Situation A Situation B

Which situation has less uncertainty?

Game 1: what color is the ball? → A

Game 2: what color is NOT the ball? → B

How to compare probability vectors

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 3 / 21

Page 10: Majorization and Entanglement transformations

Majorization

De�nition [Marshall, Olkin y Arnold, Inequalities: Theory of Majorization and Its Applications]

Let p = [p1, . . . pN ]t and q = [q1, . . . qN ]t be probability vectors: pi , qi ≥ 0

and∑N

i=1 pi = 1 =∑N

i=1 qi .p is majorized by q, denoted as p ≺ q, if

n∑i=1

p↓i ≤n∑

i=1

q↓i ∀n = 1 . . .N − 1

Example

[1

N. . .

1

N

]t≺ p ≺ [1, 0 . . . 0]t ∀p

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Page 11: Majorization and Entanglement transformations

Majorization

De�nition [Marshall, Olkin y Arnold, Inequalities: Theory of Majorization and Its Applications]

Let p = [p1, . . . pN ]t and q = [q1, . . . qN ]t be probability vectors: pi , qi ≥ 0

and∑N

i=1 pi = 1 =∑N

i=1 qi .

p is majorized by q, denoted as p ≺ q, if

n∑i=1

p↓i ≤n∑

i=1

q↓i ∀n = 1 . . .N − 1

Example

[1

N. . .

1

N

]t≺ p ≺ [1, 0 . . . 0]t ∀p

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 4 / 21

Page 12: Majorization and Entanglement transformations

Majorization

De�nition [Marshall, Olkin y Arnold, Inequalities: Theory of Majorization and Its Applications]

Let p = [p1, . . . pN ]t and q = [q1, . . . qN ]t be probability vectors: pi , qi ≥ 0

and∑N

i=1 pi = 1 =∑N

i=1 qi .p is majorized by q, denoted as p ≺ q, if

n∑i=1

p↓i ≤n∑

i=1

q↓i ∀n = 1 . . .N − 1

Example

[1

N. . .

1

N

]t≺ p ≺ [1, 0 . . . 0]t ∀p

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 4 / 21

Page 13: Majorization and Entanglement transformations

Majorization

De�nition [Marshall, Olkin y Arnold, Inequalities: Theory of Majorization and Its Applications]

Let p = [p1, . . . pN ]t and q = [q1, . . . qN ]t be probability vectors: pi , qi ≥ 0

and∑N

i=1 pi = 1 =∑N

i=1 qi .p is majorized by q, denoted as p ≺ q, if

n∑i=1

p↓i ≤n∑

i=1

q↓i ∀n = 1 . . .N − 1

Example

[1

N. . .

1

N

]t≺ p ≺ [1, 0 . . . 0]t ∀p

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 4 / 21

Page 14: Majorization and Entanglement transformations

Alternative de�nitions

De�nitions

p ≺ q sii

1 there exist a double stochastic matrix D such that

p = Dq with∑i

Dij =∑j

Dij = 1

2∑N

i=1 φ(pi ) ≤∑N

i=1 φ(qi ) for all concave function φ

Schur-concavity and entropies

Φ : RN 7→ R is Schur-concave if p ≺ q ⇒ Φ(p) ≥ Φ(q)

Shannon entropy: H(p) = −∑

pi ln pi

Tsallis entropy: Tq(p) =∑

pqi −1

1−q

Rényi entropy: Rq(p) =ln

∑pqi

1−q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 5 / 21

Page 15: Majorization and Entanglement transformations

Alternative de�nitions

De�nitions

p ≺ q sii

1 there exist a double stochastic matrix D such that

p = Dq with∑i

Dij =∑j

Dij = 1

2∑N

i=1 φ(pi ) ≤∑N

i=1 φ(qi ) for all concave function φ

Schur-concavity and entropies

Φ : RN 7→ R is Schur-concave if p ≺ q ⇒ Φ(p) ≥ Φ(q)

Shannon entropy: H(p) = −∑

pi ln pi

Tsallis entropy: Tq(p) =∑

pqi −1

1−q

Rényi entropy: Rq(p) =ln

∑pqi

1−q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 5 / 21

Page 16: Majorization and Entanglement transformations

Alternative de�nitions

De�nitions

p ≺ q sii

1 there exist a double stochastic matrix D such that

p = Dq with∑i

Dij =∑j

Dij = 1

2∑N

i=1 φ(pi ) ≤∑N

i=1 φ(qi ) for all concave function φ

Schur-concavity and entropies

Φ : RN 7→ R is Schur-concave if p ≺ q ⇒ Φ(p) ≥ Φ(q)

Shannon entropy: H(p) = −∑

pi ln pi

Tsallis entropy: Tq(p) =∑

pqi −1

1−q

Rényi entropy: Rq(p) =ln

∑pqi

1−q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 5 / 21

Page 17: Majorization and Entanglement transformations

Alternative de�nitions

De�nitions

p ≺ q sii

1 there exist a double stochastic matrix D such that

p = Dq with∑i

Dij =∑j

Dij = 1

2∑N

i=1 φ(pi ) ≤∑N

i=1 φ(qi ) for all concave function φ

Schur-concavity and entropies

Φ : RN 7→ R is Schur-concave if p ≺ q ⇒ Φ(p) ≥ Φ(q)

Shannon entropy: H(p) = −∑

pi ln pi

Tsallis entropy: Tq(p) =∑

pqi −1

1−q

Rényi entropy: Rq(p) =ln

∑pqi

1−q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 5 / 21

Page 18: Majorization and Entanglement transformations

Alternative de�nitions

De�nitions

p ≺ q sii

1 there exist a double stochastic matrix D such that

p = Dq with∑i

Dij =∑j

Dij = 1

2∑N

i=1 φ(pi ) ≤∑N

i=1 φ(qi ) for all concave function φ

Schur-concavity and entropies

Φ : RN 7→ R is Schur-concave if p ≺ q ⇒ Φ(p) ≥ Φ(q)

Shannon entropy: H(p) = −∑

pi ln pi

Tsallis entropy: Tq(p) =∑

pqi −1

1−q

Rényi entropy: Rq(p) =ln

∑pqi

1−q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 5 / 21

Page 19: Majorization and Entanglement transformations

Alternative de�nitions

De�nitions

p ≺ q sii

1 there exist a double stochastic matrix D such that

p = Dq with∑i

Dij =∑j

Dij = 1

2∑N

i=1 φ(pi ) ≤∑N

i=1 φ(qi ) for all concave function φ

Schur-concavity and entropies

Φ : RN 7→ R is Schur-concave if p ≺ q ⇒ Φ(p) ≥ Φ(q)

Shannon entropy: H(p) = −∑

pi ln pi

Tsallis entropy: Tq(p) =∑

pqi −1

1−q

Rényi entropy: Rq(p) =ln

∑pqi

1−q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 5 / 21

Page 20: Majorization and Entanglement transformations

Alternative de�nitions

De�nitions

p ≺ q sii

1 there exist a double stochastic matrix D such that

p = Dq with∑i

Dij =∑j

Dij = 1

2∑N

i=1 φ(pi ) ≤∑N

i=1 φ(qi ) for all concave function φ

Schur-concavity and entropies

Φ : RN 7→ R is Schur-concave if p ≺ q ⇒ Φ(p) ≥ Φ(q)

Shannon entropy: H(p) = −∑

pi ln pi

Tsallis entropy: Tq(p) =∑

pqi −1

1−q

Rényi entropy: Rq(p) =ln

∑pqi

1−q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 5 / 21

Page 21: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supreumum

Set of probability vectors

Let δN ={

[p1, . . . , pN ]t : pi ≥ pi+1 ≥ 0, and∑N

i=1 pi = 1 ≥ pi

}Partially ordered set (POSET)

For all p, q, r ∈ δN one has

re�exivity: p ≺ p

antisymmetry: if p ≺ q and q ≺ p, then p = q

transitivity: if p ≺ q and q ≺ r , then p ≺ r

Majorization is NOT a total order

If p = [0.6, 0.2, 0.2]t and q = [0.5, 0.4, 0.1]t , then p ⊀ q and q ⊀ p.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 6 / 21

Page 22: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supreumum

Set of probability vectors

Let δN ={

[p1, . . . , pN ]t : pi ≥ pi+1 ≥ 0, and∑N

i=1 pi = 1 ≥ pi

}

Partially ordered set (POSET)

For all p, q, r ∈ δN one has

re�exivity: p ≺ p

antisymmetry: if p ≺ q and q ≺ p, then p = q

transitivity: if p ≺ q and q ≺ r , then p ≺ r

Majorization is NOT a total order

If p = [0.6, 0.2, 0.2]t and q = [0.5, 0.4, 0.1]t , then p ⊀ q and q ⊀ p.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 6 / 21

Page 23: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supreumum

Set of probability vectors

Let δN ={

[p1, . . . , pN ]t : pi ≥ pi+1 ≥ 0, and∑N

i=1 pi = 1 ≥ pi

}Partially ordered set (POSET)

For all p, q, r ∈ δN one has

re�exivity: p ≺ p

antisymmetry: if p ≺ q and q ≺ p, then p = q

transitivity: if p ≺ q and q ≺ r , then p ≺ r

Majorization is NOT a total order

If p = [0.6, 0.2, 0.2]t and q = [0.5, 0.4, 0.1]t , then p ⊀ q and q ⊀ p.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 6 / 21

Page 24: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supreumum

Set of probability vectors

Let δN ={

[p1, . . . , pN ]t : pi ≥ pi+1 ≥ 0, and∑N

i=1 pi = 1 ≥ pi

}Partially ordered set (POSET)

For all p, q, r ∈ δN one has

re�exivity: p ≺ p

antisymmetry: if p ≺ q and q ≺ p, then p = q

transitivity: if p ≺ q and q ≺ r , then p ≺ r

Majorization is NOT a total order

If p = [0.6, 0.2, 0.2]t and q = [0.5, 0.4, 0.1]t , then p ⊀ q and q ⊀ p.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 6 / 21

Page 25: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supreumum

Set of probability vectors

Let δN ={

[p1, . . . , pN ]t : pi ≥ pi+1 ≥ 0, and∑N

i=1 pi = 1 ≥ pi

}Partially ordered set (POSET)

For all p, q, r ∈ δN one has

re�exivity: p ≺ p

antisymmetry: if p ≺ q and q ≺ p, then p = q

transitivity: if p ≺ q and q ≺ r , then p ≺ r

Majorization is NOT a total order

If p = [0.6, 0.2, 0.2]t and q = [0.5, 0.4, 0.1]t , then p ⊀ q and q ⊀ p.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 6 / 21

Page 26: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supreumum

Set of probability vectors

Let δN ={

[p1, . . . , pN ]t : pi ≥ pi+1 ≥ 0, and∑N

i=1 pi = 1 ≥ pi

}Partially ordered set (POSET)

For all p, q, r ∈ δN one has

re�exivity: p ≺ p

antisymmetry: if p ≺ q and q ≺ p, then p = q

transitivity: if p ≺ q and q ≺ r , then p ≺ r

Majorization is NOT a total order

If p = [0.6, 0.2, 0.2]t and q = [0.5, 0.4, 0.1]t , then p ⊀ q and q ⊀ p.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 6 / 21

Page 27: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supreumum

Set of probability vectors

Let δN ={

[p1, . . . , pN ]t : pi ≥ pi+1 ≥ 0, and∑N

i=1 pi = 1 ≥ pi

}Partially ordered set (POSET)

For all p, q, r ∈ δN one has

re�exivity: p ≺ p

antisymmetry: if p ≺ q and q ≺ p, then p = q

transitivity: if p ≺ q and q ≺ r , then p ≺ r

Majorization is NOT a total order

If p = [0.6, 0.2, 0.2]t and q = [0.5, 0.4, 0.1]t , then p ⊀ q and q ⊀ p.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 6 / 21

Page 28: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supreumum

Set of probability vectors

Let δN ={

[p1, . . . , pN ]t : pi ≥ pi+1 ≥ 0, and∑N

i=1 pi = 1 ≥ pi

}Partially ordered set (POSET)

For all p, q, r ∈ δN one has

re�exivity: p ≺ p

antisymmetry: if p ≺ q and q ≺ p, then p = q

transitivity: if p ≺ q and q ≺ r , then p ≺ r

Majorization is NOT a total order

If p = [0.6, 0.2, 0.2]t and q = [0.5, 0.4, 0.1]t , then p ⊀ q and q ⊀ p.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 6 / 21

Page 29: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supreumum

Set of probability vectors

Let δN ={

[p1, . . . , pN ]t : pi ≥ pi+1 ≥ 0, and∑N

i=1 pi = 1 ≥ pi

}Partially ordered set (POSET)

For all p, q, r ∈ δN one has

re�exivity: p ≺ p

antisymmetry: if p ≺ q and q ≺ p, then p = q

transitivity: if p ≺ q and q ≺ r , then p ≺ r

Majorization is NOT a total order

If p = [0.6, 0.2, 0.2]t and q = [0.5, 0.4, 0.1]t , then p ⊀ q and q ⊀ p.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 6 / 21

Page 30: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supremum

Majorization lattice [Cicalese y Vaccaro, IEEE Trans. Inf. Theory 48,933 (2002)]

Let 〈δN ,≺,∧,∨〉, where for all p, q ∈ δN there exists the in�mum p ∧ qand the supremum p ∨ q.

By de�ntion, one has

in�mum: p ∧ q i�p ∧ q ≺ p and p ∧ q ≺ q and s ≺ p ∧ qfor all s such that s ≺ p and s ≺ q

s

p ∧ q

p q

Infimum

supremum: p ∨ q siip ≺ p ∨ q y q ≺ p ∧ q and p ∨ q ≺ sfor all s such that p ≺ s and q ≺ s

s

p ∨ q

p q

Supremum

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 7 / 21

Page 31: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supremum

Majorization lattice [Cicalese y Vaccaro, IEEE Trans. Inf. Theory 48,933 (2002)]

Let 〈δN ,≺,∧,∨〉, where for all p, q ∈ δN there exists the in�mum p ∧ qand the supremum p ∨ q.

By de�ntion, one has

in�mum: p ∧ q i�p ∧ q ≺ p and p ∧ q ≺ q and s ≺ p ∧ qfor all s such that s ≺ p and s ≺ q

s

p ∧ q

p q

Infimum

supremum: p ∨ q siip ≺ p ∨ q y q ≺ p ∧ q and p ∨ q ≺ sfor all s such that p ≺ s and q ≺ s

s

p ∨ q

p q

Supremum

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 7 / 21

Page 32: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supremum

Majorization lattice [Cicalese y Vaccaro, IEEE Trans. Inf. Theory 48,933 (2002)]

Let 〈δN ,≺,∧,∨〉, where for all p, q ∈ δN there exists the in�mum p ∧ qand the supremum p ∨ q.

By de�ntion, one has

in�mum: p ∧ q i�p ∧ q ≺ p and p ∧ q ≺ q and s ≺ p ∧ qfor all s such that s ≺ p and s ≺ q

s

p ∧ q

p q

Infimum

supremum: p ∨ q siip ≺ p ∨ q y q ≺ p ∧ q and p ∨ q ≺ sfor all s such that p ≺ s and q ≺ s

s

p ∨ q

p q

Supremum

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 7 / 21

Page 33: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supremum

Majorization lattice [Cicalese y Vaccaro, IEEE Trans. Inf. Theory 48,933 (2002)]

Let 〈δN ,≺,∧,∨〉, where for all p, q ∈ δN there exists the in�mum p ∧ qand the supremum p ∨ q.

By de�ntion, one has

in�mum: p ∧ q i�p ∧ q ≺ p and p ∧ q ≺ q and s ≺ p ∧ qfor all s such that s ≺ p and s ≺ q

s

p ∧ q

p q

Infimum

supremum: p ∨ q siip ≺ p ∨ q y q ≺ p ∧ q and p ∨ q ≺ sfor all s such that p ≺ s and q ≺ s

s

p ∨ q

p q

Supremum

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 7 / 21

Page 34: Majorization and Entanglement transformations

Majorization lattice: POSET + in�mum and supremum

Majorization lattice [Cicalese y Vaccaro, IEEE Trans. Inf. Theory 48,933 (2002)]

Let 〈δN ,≺,∧,∨〉, where for all p, q ∈ δN there exists the in�mum p ∧ qand the supremum p ∨ q.

By de�ntion, one has

in�mum: p ∧ q i�p ∧ q ≺ p and p ∧ q ≺ q and s ≺ p ∧ qfor all s such that s ≺ p and s ≺ q

s

p ∧ q

p q

Infimum

supremum: p ∨ q siip ≺ p ∨ q y q ≺ p ∧ q and p ∨ q ≺ sfor all s such that p ≺ s and q ≺ s

s

p ∨ q

p q

Supremum

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 7 / 21

Page 35: Majorization and Entanglement transformations

Calculating the in�mum

In�mum

Let p, q ∈ δN , the in�mum s inf ≡ p ∧ q is such that

s infi = min

{i∑

l=1

pl ,i∑

l=1

ql

}−

i−1∑l=1

s infi ,

with s inf0 ≡ 0.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 8 / 21

Page 36: Majorization and Entanglement transformations

Calculating the in�mum

In�mum

Let p, q ∈ δN , the in�mum s inf ≡ p ∧ q is such that

s infi = min

{i∑

l=1

pl ,i∑

l=1

ql

}−

i−1∑l=1

s infi ,

with s inf0 ≡ 0.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 8 / 21

Page 37: Majorization and Entanglement transformations

Calculating the supremum

Supremum

Let p, q ∈ δN , the supremum, ssup ≡ p ∨ q, is obtained as follows

1 s = [s1, . . . , sN ]t : s1 = max {p1, q1} andsi = max

{∑il=1 pl ,

∑il=1 ql

}−∑i−1

l=1 sl with i ∈ [2,N]

2 r = [r1, . . . , rN ]t :

(a) let j be the smallest integer in [2,N] such that rj > rj−1

(b) let k be the greatest integer in [1, j − 1] such that rk−1 ≥∑j

l=k rlj−k+1

= a

with r0 > 1(c) let t the probability vector given by

tl ≡{

a for l = k , k + 1, . . . , jrl otherwise.

3 Applying transformations 2.(a)− 2.(c) with the input probability

vector s, one obtains the supremum in no more than N − 1 iterations.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 9 / 21

Page 38: Majorization and Entanglement transformations

Calculating the supremum

Supremum

Let p, q ∈ δN , the supremum, ssup ≡ p ∨ q, is obtained as follows

1 s = [s1, . . . , sN ]t : s1 = max {p1, q1} andsi = max

{∑il=1 pl ,

∑il=1 ql

}−∑i−1

l=1 sl with i ∈ [2,N]

2 r = [r1, . . . , rN ]t :

(a) let j be the smallest integer in [2,N] such that rj > rj−1

(b) let k be the greatest integer in [1, j − 1] such that rk−1 ≥∑j

l=k rlj−k+1

= a

with r0 > 1(c) let t the probability vector given by

tl ≡{

a for l = k , k + 1, . . . , jrl otherwise.

3 Applying transformations 2.(a)− 2.(c) with the input probability

vector s, one obtains the supremum in no more than N − 1 iterations.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 9 / 21

Page 39: Majorization and Entanglement transformations

Calculating the supremum

Supremum

Let p, q ∈ δN , the supremum, ssup ≡ p ∨ q, is obtained as follows

1 s = [s1, . . . , sN ]t : s1 = max {p1, q1} andsi = max

{∑il=1 pl ,

∑il=1 ql

}−∑i−1

l=1 sl with i ∈ [2,N]

2 r = [r1, . . . , rN ]t :

(a) let j be the smallest integer in [2,N] such that rj > rj−1

(b) let k be the greatest integer in [1, j − 1] such that rk−1 ≥∑j

l=k rlj−k+1

= a

with r0 > 1(c) let t the probability vector given by

tl ≡{

a for l = k, k + 1, . . . , jrl otherwise.

3 Applying transformations 2.(a)− 2.(c) with the input probability

vector s, one obtains the supremum in no more than N − 1 iterations.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 9 / 21

Page 40: Majorization and Entanglement transformations

Calculating the supremum

Supremum

Let p, q ∈ δN , the supremum, ssup ≡ p ∨ q, is obtained as follows

1 s = [s1, . . . , sN ]t : s1 = max {p1, q1} andsi = max

{∑il=1 pl ,

∑il=1 ql

}−∑i−1

l=1 sl with i ∈ [2,N]

2 r = [r1, . . . , rN ]t :

(a) let j be the smallest integer in [2,N] such that rj > rj−1

(b) let k be the greatest integer in [1, j − 1] such that rk−1 ≥∑j

l=k rlj−k+1

= a

with r0 > 1(c) let t the probability vector given by

tl ≡{

a for l = k, k + 1, . . . , jrl otherwise.

3 Applying transformations 2.(a)− 2.(c) with the input probability

vector s, one obtains the supremum in no more than N − 1 iterations.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 9 / 21

Page 41: Majorization and Entanglement transformations

Calculating the supremum

Supremum

Let p, q ∈ δN , the supremum, ssup ≡ p ∨ q, is obtained as follows

1 s = [s1, . . . , sN ]t : s1 = max {p1, q1} andsi = max

{∑il=1 pl ,

∑il=1 ql

}−∑i−1

l=1 sl with i ∈ [2,N]

2 r = [r1, . . . , rN ]t :

(a) let j be the smallest integer in [2,N] such that rj > rj−1

(b) let k be the greatest integer in [1, j − 1] such that rk−1 ≥∑j

l=k rlj−k+1

= a

with r0 > 1(c) let t the probability vector given by

tl ≡{

a for l = k, k + 1, . . . , jrl otherwise.

3 Applying transformations 2.(a)− 2.(c) with the input probability

vector s, one obtains the supremum in no more than N − 1 iterations.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 9 / 21

Page 42: Majorization and Entanglement transformations

Calculating the supremum

Supremum

Let p, q ∈ δN , the supremum, ssup ≡ p ∨ q, is obtained as follows

1 s = [s1, . . . , sN ]t : s1 = max {p1, q1} andsi = max

{∑il=1 pl ,

∑il=1 ql

}−∑i−1

l=1 sl with i ∈ [2,N]

2 r = [r1, . . . , rN ]t :

(a) let j be the smallest integer in [2,N] such that rj > rj−1

(b) let k be the greatest integer in [1, j − 1] such that rk−1 ≥∑j

l=k rlj−k+1

= a

with r0 > 1

(c) let t the probability vector given by

tl ≡{

a for l = k, k + 1, . . . , jrl otherwise.

3 Applying transformations 2.(a)− 2.(c) with the input probability

vector s, one obtains the supremum in no more than N − 1 iterations.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 9 / 21

Page 43: Majorization and Entanglement transformations

Calculating the supremum

Supremum

Let p, q ∈ δN , the supremum, ssup ≡ p ∨ q, is obtained as follows

1 s = [s1, . . . , sN ]t : s1 = max {p1, q1} andsi = max

{∑il=1 pl ,

∑il=1 ql

}−∑i−1

l=1 sl with i ∈ [2,N]

2 r = [r1, . . . , rN ]t :

(a) let j be the smallest integer in [2,N] such that rj > rj−1

(b) let k be the greatest integer in [1, j − 1] such that rk−1 ≥∑j

l=k rlj−k+1

= a

with r0 > 1(c) let t the probability vector given by

tl ≡{

a for l = k , k + 1, . . . , jrl otherwise.

3 Applying transformations 2.(a)− 2.(c) with the input probability

vector s, one obtains the supremum in no more than N − 1 iterations.

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 9 / 21

Page 44: Majorization and Entanglement transformations

Calculating the supremum

Supremum

Let p, q ∈ δN , the supremum, ssup ≡ p ∨ q, is obtained as follows

1 s = [s1, . . . , sN ]t : s1 = max {p1, q1} andsi = max

{∑il=1 pl ,

∑il=1 ql

}−∑i−1

l=1 sl with i ∈ [2,N]

2 r = [r1, . . . , rN ]t :

(a) let j be the smallest integer in [2,N] such that rj > rj−1

(b) let k be the greatest integer in [1, j − 1] such that rk−1 ≥∑j

l=k rlj−k+1

= a

with r0 > 1(c) let t the probability vector given by

tl ≡{

a for l = k , k + 1, . . . , jrl otherwise.

3 Applying transformations 2.(a)− 2.(c) with the input probability

vector s, one obtains the supremum in no more than N − 1 iterations.GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 9 / 21

Page 45: Majorization and Entanglement transformations

Continuation

Example

If p = [0.6, 0.15, 0.15, 0.1]t y q = [0.5, 0.25, 0.20, 0.05]t , then

p ∧ q = [0.5, 0.25, 0.15, 0.1]t

p ∨ q = [0.6, 0.175, 0.175, 0.05]t

Properties

bottom element: s0 ≡[1N . . .

1N

]ttop element: s1 ≡ [1, 0 . . . 0]t

majorization lattice is NOT modular:

if r ≺ q ; r ∨ (p ∧ q) = (r ∨ p) ∧ qp q

r

p ∧ q

p ∨ q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 10 / 21

Page 46: Majorization and Entanglement transformations

Continuation

Example

If p = [0.6, 0.15, 0.15, 0.1]t y q = [0.5, 0.25, 0.20, 0.05]t , then

p ∧ q = [0.5, 0.25, 0.15, 0.1]t

p ∨ q = [0.6, 0.175, 0.175, 0.05]t

Properties

bottom element: s0 ≡[1N . . .

1N

]ttop element: s1 ≡ [1, 0 . . . 0]t

majorization lattice is NOT modular:

if r ≺ q ; r ∨ (p ∧ q) = (r ∨ p) ∧ qp q

r

p ∧ q

p ∨ q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 10 / 21

Page 47: Majorization and Entanglement transformations

Continuation

Example

If p = [0.6, 0.15, 0.15, 0.1]t y q = [0.5, 0.25, 0.20, 0.05]t , then

p ∧ q = [0.5, 0.25, 0.15, 0.1]t

p ∨ q = [0.6, 0.175, 0.175, 0.05]t

Properties

bottom element: s0 ≡[1N . . .

1N

]ttop element: s1 ≡ [1, 0 . . . 0]t

majorization lattice is NOT modular:

if r ≺ q ; r ∨ (p ∧ q) = (r ∨ p) ∧ qp q

r

p ∧ q

p ∨ q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 10 / 21

Page 48: Majorization and Entanglement transformations

Continuation

Example

If p = [0.6, 0.15, 0.15, 0.1]t y q = [0.5, 0.25, 0.20, 0.05]t , then

p ∧ q = [0.5, 0.25, 0.15, 0.1]t

p ∨ q = [0.6, 0.175, 0.175, 0.05]t

Properties

bottom element: s0 ≡[1N . . .

1N

]ttop element: s1 ≡ [1, 0 . . . 0]t

majorization lattice is NOT modular:

if r ≺ q ; r ∨ (p ∧ q) = (r ∨ p) ∧ qp q

r

p ∧ q

p ∨ q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 10 / 21

Page 49: Majorization and Entanglement transformations

Continuation

Example

If p = [0.6, 0.15, 0.15, 0.1]t y q = [0.5, 0.25, 0.20, 0.05]t , then

p ∧ q = [0.5, 0.25, 0.15, 0.1]t

p ∨ q = [0.6, 0.175, 0.175, 0.05]t

Properties

bottom element: s0 ≡[1N . . .

1N

]ttop element: s1 ≡ [1, 0 . . . 0]t

majorization lattice is NOT modular:

if r ≺ q ; r ∨ (p ∧ q) = (r ∨ p) ∧ qp q

r

p ∧ q

p ∨ q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 10 / 21

Page 50: Majorization and Entanglement transformations

Continuation

Example

If p = [0.6, 0.15, 0.15, 0.1]t y q = [0.5, 0.25, 0.20, 0.05]t , then

p ∧ q = [0.5, 0.25, 0.15, 0.1]t

p ∨ q = [0.6, 0.175, 0.175, 0.05]t

Properties

bottom element: s0 ≡[1N . . .

1N

]ttop element: s1 ≡ [1, 0 . . . 0]t

majorization lattice is NOT modular:

if r ≺ q ; r ∨ (p ∧ q) = (r ∨ p) ∧ qp q

r

p ∧ q

p ∨ q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 10 / 21

Page 51: Majorization and Entanglement transformations

Continuation

Example

If p = [0.6, 0.15, 0.15, 0.1]t y q = [0.5, 0.25, 0.20, 0.05]t , then

p ∧ q = [0.5, 0.25, 0.15, 0.1]t

p ∨ q = [0.6, 0.175, 0.175, 0.05]t

Properties

bottom element: s0 ≡[1N . . .

1N

]t

top element: s1 ≡ [1, 0 . . . 0]t

majorization lattice is NOT modular:

if r ≺ q ; r ∨ (p ∧ q) = (r ∨ p) ∧ qp q

r

p ∧ q

p ∨ q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 10 / 21

Page 52: Majorization and Entanglement transformations

Continuation

Example

If p = [0.6, 0.15, 0.15, 0.1]t y q = [0.5, 0.25, 0.20, 0.05]t , then

p ∧ q = [0.5, 0.25, 0.15, 0.1]t

p ∨ q = [0.6, 0.175, 0.175, 0.05]t

Properties

bottom element: s0 ≡[1N . . .

1N

]ttop element: s1 ≡ [1, 0 . . . 0]t

majorization lattice is NOT modular:

if r ≺ q ; r ∨ (p ∧ q) = (r ∨ p) ∧ qp q

r

p ∧ q

p ∨ q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 10 / 21

Page 53: Majorization and Entanglement transformations

Continuation

Example

If p = [0.6, 0.15, 0.15, 0.1]t y q = [0.5, 0.25, 0.20, 0.05]t , then

p ∧ q = [0.5, 0.25, 0.15, 0.1]t

p ∨ q = [0.6, 0.175, 0.175, 0.05]t

Properties

bottom element: s0 ≡[1N . . .

1N

]ttop element: s1 ≡ [1, 0 . . . 0]t

majorization lattice is NOT modular:

if r ≺ q ; r ∨ (p ∧ q) = (r ∨ p) ∧ qp q

r

p ∧ q

p ∨ q

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 10 / 21

Page 54: Majorization and Entanglement transformations

Part II

Entanglement transformations

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 11 / 21

Page 55: Majorization and Entanglement transformations

Local operations and classical communication (LOCC)

Alice y Bob share an initial entangled pure state |ψ〉Goal: obtain the target entangled pure state |φ〉 by using

local operations and classical communications (LOCC)

which is the condition for this process of entanglementtransformation to be possible?

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 12 / 21

Page 56: Majorization and Entanglement transformations

Local operations and classical communication (LOCC)

Alice y Bob share an initial entangled pure state |ψ〉

Goal: obtain the target entangled pure state |φ〉 by using

local operations and classical communications (LOCC)

which is the condition for this process of entanglementtransformation to be possible?

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 12 / 21

Page 57: Majorization and Entanglement transformations

Local operations and classical communication (LOCC)

Alice y Bob share an initial entangled pure state |ψ〉Goal: obtain the target entangled pure state |φ〉 by using

local operations and classical communications (LOCC)

which is the condition for this process of entanglementtransformation to be possible?

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 12 / 21

Page 58: Majorization and Entanglement transformations

Local operations and classical communication (LOCC)

Alice y Bob share an initial entangled pure state |ψ〉Goal: obtain the target entangled pure state |φ〉 by using

local operations and classical communications (LOCC)

which is the condition for this process of entanglementtransformation to be possible?

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 12 / 21

Page 59: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 60: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 61: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 62: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 63: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉

if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 64: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if

ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 65: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 66: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 67: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 68: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 69: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 70: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 71: Majorization and Entanglement transformations

Entanglement transformation and majorization

Nielsen Theorem [Phys. Rev. Lett. 83, 436 (1999)]

Let consider the Schmidt decomposition of the states:

initial: |ψ〉 =∑N

i=1

√ψi |iA〉 |iB〉 con ψ = [ψ1, . . . , ψN ] ∈ δN

target: |φ〉 =∑N

j=1

√φj |jA〉 |jB〉 con φ = [φ1, . . . , φN ] ∈ δN

|ψ〉 →LOCC

|φ〉 if and only if ψ ≺ φ

This condition does not depend on the Schmidt basis

As it is expected, the Nielsen condition is not satis�ed in general

Example

|ψ〉 =√0.6 |00〉+

√0.15 |11〉+

√0.15 |22〉+

√0.1 |33〉

|φ〉 =√0.5 |00〉+

√0.25 |11〉+

√0.2 |22〉+

√0.05 |33〉

one has |ψ〉 =LOCC

|φ〉 due to ψ ⊀ φ and φ ⊀ ψ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 13 / 21

Page 72: Majorization and Entanglement transformations

Approximate entanglement transformations

initial state|ψ〉

target state

|φ〉

\

|χ1〉...|χM〉

Goal: �nd |χ〉 closest to |φ〉

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 14 / 21

Page 73: Majorization and Entanglement transformations

Approximate entanglement transformations

initial state|ψ〉

target state

|φ〉\

|χ1〉...|χM〉

Goal: �nd |χ〉 closest to |φ〉

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 14 / 21

Page 74: Majorization and Entanglement transformations

Approximate entanglement transformations

initial state|ψ〉

target state

|φ〉\

|χ1〉

...|χM〉

Goal: �nd |χ〉 closest to |φ〉

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 14 / 21

Page 75: Majorization and Entanglement transformations

Approximate entanglement transformations

initial state|ψ〉

target state

|φ〉\

|χ1〉

...

|χM〉

Goal: �nd |χ〉 closest to |φ〉

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 14 / 21

Page 76: Majorization and Entanglement transformations

Approximate entanglement transformations

initial state|ψ〉

target state

|φ〉\

|χ1〉...|χM〉

Goal: �nd |χ〉 closest to |φ〉

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 14 / 21

Page 77: Majorization and Entanglement transformations

Approximate entanglement transformations

initial state|ψ〉

target state

|φ〉\

|χ1〉...|χM〉

Goal: �nd |χ〉 closest to |φ〉

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 14 / 21

Page 78: Majorization and Entanglement transformations

Approximate entanglement transformations with Fidelity

Vidal et. al Criterion [Phys. Rev. A 62, 012304 (2000)]

Let |ψ〉 and |φ〉 be the initial and target such that |ψ〉 9LOCC

|φ〉.

They de�ne |χopt〉 as the closest to the target in the sense of maximal

�delity:

|χopt〉 = argmax|χ〉:|ψ〉 →

LOCC|χ〉F (|φ〉 , |χ〉),

where F (|φ〉 , |χ〉) = | 〈φ|χ〉 |2 is the �delity between the states |φ〉 and |χ〉

Equivalent problem

χopt = arg maxχ:ψ≺χ

F (φ, χ)

where F (φ, χ) =(∑

i

√φiχi

)2is the �delity between the vectors φ and χ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 15 / 21

Page 79: Majorization and Entanglement transformations

Approximate entanglement transformations with Fidelity

Vidal et. al Criterion [Phys. Rev. A 62, 012304 (2000)]

Let |ψ〉 and |φ〉 be the initial and target such that |ψ〉 9LOCC

|φ〉.They de�ne |χopt〉 as the closest to the target in the sense of maximal

�delity:

|χopt〉 = argmax|χ〉:|ψ〉 →

LOCC|χ〉F (|φ〉 , |χ〉),

where F (|φ〉 , |χ〉) = | 〈φ|χ〉 |2 is the �delity between the states |φ〉 and |χ〉

Equivalent problem

χopt = arg maxχ:ψ≺χ

F (φ, χ)

where F (φ, χ) =(∑

i

√φiχi

)2is the �delity between the vectors φ and χ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 15 / 21

Page 80: Majorization and Entanglement transformations

Approximate entanglement transformations with Fidelity

Vidal et. al Criterion [Phys. Rev. A 62, 012304 (2000)]

Let |ψ〉 and |φ〉 be the initial and target such that |ψ〉 9LOCC

|φ〉.They de�ne |χopt〉 as the closest to the target in the sense of maximal

�delity:

|χopt〉 = argmax|χ〉:|ψ〉 →

LOCC|χ〉F (|φ〉 , |χ〉),

where F (|φ〉 , |χ〉) = | 〈φ|χ〉 |2 is the �delity between the states |φ〉 and |χ〉

Equivalent problem

χopt = arg maxχ:ψ≺χ

F (φ, χ)

where F (φ, χ) =(∑

i

√φiχi

)2is the �delity between the vectors φ and χ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 15 / 21

Page 81: Majorization and Entanglement transformations

Approximate entanglement transformations with Fidelity

Vidal et. al Criterion [Phys. Rev. A 62, 012304 (2000)]

Let |ψ〉 and |φ〉 be the initial and target such that |ψ〉 9LOCC

|φ〉.They de�ne |χopt〉 as the closest to the target in the sense of maximal

�delity:

|χopt〉 = argmax|χ〉:|ψ〉 →

LOCC|χ〉F (|φ〉 , |χ〉),

where F (|φ〉 , |χ〉) = | 〈φ|χ〉 |2 is the �delity between the states |φ〉 and |χ〉

Equivalent problem

χopt = arg maxχ:ψ≺χ

F (φ, χ)

where F (φ, χ) =(∑

i

√φiχi

)2is the �delity between the vectors φ and χ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 15 / 21

Page 82: Majorization and Entanglement transformations

Expression of the optimum: χopt

χopt =

rk

φlk = φ1...

φlk−1−1

...

r2

φl2...

φl2−1−1

r1

φl1...

φl1−1−1 = φN

with lk the least integer in [1, lk − 1]such that

rk = minl∈[1,lk−1−1]

El(ψ)− Elk−1(ψ)

El(φ)− Elk−1(φ)

where El(ψ) =∑N

l ′=l ψl ′ for all

l = 1, . . . ,N

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 16 / 21

Page 83: Majorization and Entanglement transformations

Expression of the optimum: χopt

χopt =

rk

φlk = φ1...

φlk−1−1

...

r2

φl2...

φl2−1−1

r1

φl1...

φl1−1−1 = φN

with lk the least integer in [1, lk − 1]such that

rk = minl∈[1,lk−1−1]

El(ψ)− Elk−1(ψ)

El(φ)− Elk−1(φ)

where El(ψ) =∑N

l ′=l ψl ′ for all

l = 1, . . . ,N

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 16 / 21

Page 84: Majorization and Entanglement transformations

Expression of the optimum: χopt

χopt =

rk

φlk = φ1...

φlk−1−1

...

r2

φl2...

φl2−1−1

r1

φl1...

φl1−1−1 = φN

with lk the least integer in [1, lk − 1]such that

rk = minl∈[1,lk−1−1]

El(ψ)− Elk−1(ψ)

El(φ)− Elk−1(φ)

where El(ψ) =∑N

l ′=l ψl ′ for all

l = 1, . . . ,N

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 16 / 21

Page 85: Majorization and Entanglement transformations

Relationship with the supremum

Does the lattice structure of majorization play some role?

Theorem [GMB, G. Sergioli, H. Freytes, F. Holik and G. Bellomo]

Let |ψ〉 and |φ〉 the initial and target states, one has

φ ≺ χsup ≺ χopt

where χsup ≡ ψ ∨ φ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 17 / 21

Page 86: Majorization and Entanglement transformations

Relationship with the supremum

Does the lattice structure of majorization play some role?

Theorem [GMB, G. Sergioli, H. Freytes, F. Holik and G. Bellomo]

Let |ψ〉 and |φ〉 the initial and target states, one has

φ ≺ χsup ≺ χopt

where χsup ≡ ψ ∨ φ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 17 / 21

Page 87: Majorization and Entanglement transformations

Relationship with the supremum

Does the lattice structure of majorization play some role?

Theorem [GMB, G. Sergioli, H. Freytes, F. Holik and G. Bellomo]

Let |ψ〉 and |φ〉 the initial and target states, one has

φ ≺ χsup ≺ χopt

where χsup ≡ ψ ∨ φ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 17 / 21

Page 88: Majorization and Entanglement transformations

Relationship with the supremum

Does the lattice structure of majorization play some role?

Theorem [GMB, G. Sergioli, H. Freytes, F. Holik and G. Bellomo]

Let |ψ〉 and |φ〉 the initial and target states, one has

φ ≺ χsup ≺ χopt

where χsup ≡ ψ ∨ φ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 17 / 21

Page 89: Majorization and Entanglement transformations

Relationship with the supremum

Theorem [GMB, G. Sergioli, H. Freytes, F. Holik and G. Bellomo]

Let |ψ〉 and |φ〉 the initial and target states, one has

φ ≺ χsup ≺ χopt

where χsup ≡ ψ ∨ φ

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 18 / 21

Page 90: Majorization and Entanglement transformations

Relationship with the supremum

Theorem [GMB, G. Sergioli, H. Freytes, F. Holik and G. Bellomo]

Let |ψ〉 and |φ〉 the initial and target states, one has

φ ≺ χsup ≺ χopt

where χsup ≡ ψ ∨ φ

ψ

φ

Case 1: if |ψ〉 →LOCC

|φ〉

= χsup = χopt

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 18 / 21

Page 91: Majorization and Entanglement transformations

Relationship with the supremum

Theorem [GMB, G. Sergioli, H. Freytes, F. Holik and G. Bellomo]

Let |ψ〉 and |φ〉 the initial and target states, one has

φ ≺ χsup ≺ χopt

where χsup ≡ ψ ∨ φ

φ

ψ

χopt

Case 2: if |ψ〉 9LOCC

|φ〉 and |ψ〉 ←LOCC

|φ〉

= χsup

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 18 / 21

Page 92: Majorization and Entanglement transformations

Relationship with the supremum

Theorem [GMB, G. Sergioli, H. Freytes, F. Holik and G. Bellomo]

Let |ψ〉 and |φ〉 the initial and target states, one has

φ ≺ χsup ≺ χopt

where χsup ≡ ψ ∨ φ

χsup χopt

φ ψ

(a) χsup ⊀ χopt and χopt ⊀ χsup

χsup

χopt

φ ψ

(b) χopt ≺ χsup

χopt

χsup

φ ψ

(c) χsup ≺ χopt

Case 3: |ψ〉 =LOCC

|φ〉

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 18 / 21

Page 93: Majorization and Entanglement transformations

Fidelity vs. majorization

Example

Let:

ψ = [0.6, 0.15, 0.15, 0.1]t

φ = [0.5, 0.25, 0.2, 0.5]t

one has

χopt = [0.6, 0.2, 0.16, 0.4]t with �delity F (φ, χopt) ≈ 0.989

χsup = [0.6, 0.175, 0.175, 0.05]t with �delity F (φ, χsup) ≈ 0.987

But, we have seen that:

φ ≺ χsup ≺ χopt

Fidelity does not respect the majorization order in general

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 19 / 21

Page 94: Majorization and Entanglement transformations

Fidelity vs. majorization

Example

Let:

ψ = [0.6, 0.15, 0.15, 0.1]t

φ = [0.5, 0.25, 0.2, 0.5]t

one has

χopt = [0.6, 0.2, 0.16, 0.4]t with �delity F (φ, χopt) ≈ 0.989

χsup = [0.6, 0.175, 0.175, 0.05]t with �delity F (φ, χsup) ≈ 0.987

But, we have seen that:

φ ≺ χsup ≺ χopt

Fidelity does not respect the majorization order in general

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 19 / 21

Page 95: Majorization and Entanglement transformations

Fidelity vs. majorization

Example

Let:

ψ = [0.6, 0.15, 0.15, 0.1]t

φ = [0.5, 0.25, 0.2, 0.5]t

one has

χopt = [0.6, 0.2, 0.16, 0.4]t with �delity F (φ, χopt) ≈ 0.989

χsup = [0.6, 0.175, 0.175, 0.05]t with �delity F (φ, χsup) ≈ 0.987

But, we have seen that:

φ ≺ χsup ≺ χopt

Fidelity does not respect the majorization order in general

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 19 / 21

Page 96: Majorization and Entanglement transformations

Fidelity vs. majorization

Example

Let:

ψ = [0.6, 0.15, 0.15, 0.1]t

φ = [0.5, 0.25, 0.2, 0.5]t

one has

χopt = [0.6, 0.2, 0.16, 0.4]t with �delity F (φ, χopt) ≈ 0.989

χsup = [0.6, 0.175, 0.175, 0.05]t with �delity F (φ, χsup) ≈ 0.987

But, we have seen that:

φ ≺ χsup ≺ χopt

Fidelity does not respect the majorization order in general

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 19 / 21

Page 97: Majorization and Entanglement transformations

Fidelity vs. majorization

Example

Let:

ψ = [0.6, 0.15, 0.15, 0.1]t

φ = [0.5, 0.25, 0.2, 0.5]t

one has

χopt = [0.6, 0.2, 0.16, 0.4]t with �delity F (φ, χopt) ≈ 0.989

χsup = [0.6, 0.175, 0.175, 0.05]t with �delity F (φ, χsup) ≈ 0.987

But, we have seen that:

φ ≺ χsup ≺ χopt

Fidelity does not respect the majorization order in general

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 19 / 21

Page 98: Majorization and Entanglement transformations

Fidelity vs. majorization

Example

Let:

ψ = [0.6, 0.15, 0.15, 0.1]t

φ = [0.5, 0.25, 0.2, 0.5]t

one has

χopt = [0.6, 0.2, 0.16, 0.4]t with �delity F (φ, χopt) ≈ 0.989

χsup = [0.6, 0.175, 0.175, 0.05]t with �delity F (φ, χsup) ≈ 0.987

But, we have seen that:

φ ≺ χsup ≺ χopt

Fidelity does not respect the majorization order in general

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 19 / 21

Page 99: Majorization and Entanglement transformations

Fidelity vs. majorization

Example

Let:

ψ = [0.6, 0.15, 0.15, 0.1]t

φ = [0.5, 0.25, 0.2, 0.5]t

one has

χopt = [0.6, 0.2, 0.16, 0.4]t with �delity F (φ, χopt) ≈ 0.989

χsup = [0.6, 0.175, 0.175, 0.05]t with �delity F (φ, χsup) ≈ 0.987

But, we have seen that:

φ ≺ χsup ≺ χopt

Fidelity does not respect the majorization order in general

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 19 / 21

Page 100: Majorization and Entanglement transformations

Fidelity vs. majorization

Example

Let:

ψ = [0.6, 0.15, 0.15, 0.1]t

φ = [0.5, 0.25, 0.2, 0.5]t

one has

χopt = [0.6, 0.2, 0.16, 0.4]t with �delity F (φ, χopt) ≈ 0.989

χsup = [0.6, 0.175, 0.175, 0.05]t with �delity F (φ, χsup) ≈ 0.987

But, we have seen that:

φ ≺ χsup ≺ χopt

Fidelity does not respect the majorization order in general

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 19 / 21

Page 101: Majorization and Entanglement transformations

Fidelity vs. majorization

Example

Let:

ψ = [0.6, 0.15, 0.15, 0.1]t

φ = [0.5, 0.25, 0.2, 0.5]t

one has

χopt = [0.6, 0.2, 0.16, 0.4]t with �delity F (φ, χopt) ≈ 0.989

χsup = [0.6, 0.175, 0.175, 0.05]t with �delity F (φ, χsup) ≈ 0.987

But, we have seen that:

φ ≺ χsup ≺ χopt

Fidelity does not respect the majorization order in general

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 19 / 21

Page 102: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 103: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 104: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 105: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 106: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 107: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 108: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 109: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 110: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 111: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 112: Majorization and Entanglement transformations

Intepreting the supreum

Distance on the majorization lattice

Let two proability vectors p, q ∈ δN . A distance d is de�ned as:

d(p, q) = H(p) + H(q)− 2H(p ∨ q) con H(p) = −∑i

pi ln pi

positivity: d(p, q) ≥ 0 with d(p, q) = 0 i� p = q

symmetry: d(p, q) = d(q, p)

triangle inequality: d(p, r) + d(r , q) ≥ d(p, q)

compatible with the lattice: if p ≺ q ≺ r ⇒ d(p, r) = d(p, q) + d(q, r)

Supremum state

|ψ〉 →LOCC

|χsup〉 ≡∑j

√χsupj |jA〉 |jB〉 with χsup ≡ ψ ∨ φ

is the closest to target in the sense of minimal distance d :

|χsup〉 = argmin|χ〉:|ψ〉 →

LOCC|χ〉

d(|φ〉 , |χ〉)

it has more entanglement entropy than the optimumRecall: Entropy of Schmidt coe�cients is the entanglement entropy

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 20 / 21

Page 113: Majorization and Entanglement transformations

Grazie mille!!!

Questions, comments...

GM Bosyk (IFLP&UNICA) AMQI 2016 03/11/16 21 / 21