Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

65
Quantum Physics Mathematics

Transcript of Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Page 1: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsMathematics

Quantum PhysicsMathematics

Page 2: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsTools in Real LifeQuantum PhysicsTools in Real Life

Reality

Page 3: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsTools in Physics / Quantum PhysicsReal Number – Vector - Statevector

Quantum PhysicsTools in Physics / Quantum PhysicsReal Number – Vector - Statevector

Speed represented by a real number80 km/h

Velocity represented by a vector 80 km/h NorthEast

State representered by a statevector

v

v

yxr ,

yx vvv ,

Page 4: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsTools in Physics / Quantum PhysicsQuantum PhysicsTools in Physics / Quantum Physics

Reality

Language

Position is 2.0 m andvelocity is 4.0 m/s

Mathematics

Numbers Variables

Vectors

Functions2)( xxf 1

5 27xa

Iuyexuyxg 2),,(

df2

)(

2Lf

Hf

maF

Page 5: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

1Quantum PhysicsSuperpositionVectors - Functions

Quantum PhysicsSuperpositionVectors - Functions

Music Pulse train

Heat Sampling

1

23

4

S

Page 6: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsReality - Theory / Mathematical roomQuantum PhysicsReality - Theory / Mathematical room

Reality

Theory / Mathematical room

Page 7: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsReality - Theory / Mathematical room - Classical PhysicsQuantum PhysicsReality - Theory / Mathematical room - Classical Physics

Reality

TheoryMathematical room

va

rv

2

2

1mvK

cmamF

Page 8: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsReality - Theory / Mathematical room - Quantum PhysicsQuantum PhysicsReality - Theory / Mathematical room - Quantum Physics

Reality

TheoryMathematical room

Action

'

A

State

' State

Page 9: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsPostulate 1Quantum PhysicsPostulate 1

)(t

1.Every system is described by a state vectorthat is an element of a Hilbert space.

Page 10: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsPostulate 2Quantum PhysicsPostulate 2

2.An action or a measurement on a systemis associated with an operator.

21 A

2

1

Page 11: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsObservation / Measurement in daily lifeQuantum PhysicsObservation / Measurement in daily life

The behaviour of the classis perhaps not independentof an observation (making a video of the class)

The length of the tableis independent of an observation or a measurement.

2

1

Page 12: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsObservation of position, changing the velocityQuantum PhysicsObservation of position, changing the velocity

A ball with a known velocity and unknown position.Try to determine the position.

A bit unlucky one foot hits the ball.The position is known when the ball is touched,but now the velocity is changing.

Just after the hit of the ball,the position is known, but now the velocity is unknown.

2

1

Page 13: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsObservation of current and voltageQuantum PhysicsObservation of current and voltage

2

1

Input of amperemeter and voltmeterdisturb the current and voltage.

Page 14: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsStern-Gerlach experiment [1/2]Observation of angular momentum in one directioninfluence on the angular momentum in another direction

Quantum PhysicsStern-Gerlach experiment [1/2]Observation of angular momentum in one directioninfluence on the angular momentum in another direction

Silver atoms going through a vertical magnetic fielddividing the beam into two new beamsdependent of the angular momentum of the atom.

Three magnetic fields: Vertical, horizontal, vertical.Every time the beam is divided into two new beams.

No sorting mechanism.A new vertical/horisontal measurementdisturbs/changes the horisontal/vertical beam property.

2

1

V1

V1

H1

V2

B1

B2

B1

B121

B2

B11

B12

B122

B

B

Page 15: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsStern-Gerlach experiment [2/2]Observation of angular momentum in one directioninfluence on the angular momentum in another direction

Quantum PhysicsStern-Gerlach experiment [2/2]Observation of angular momentum in one directioninfluence on the angular momentum in another direction

2

1

BS-Gz-axis

z+

z-

S-Gx-axis

x+

x-

S-Gz-axis

BS-Gz-axis

z+

z-

S-Gx-axis

BS-Gz-axis

z+

z-

S-Gz-axis

z+

No z-

x+

x-

z+

z-

1

2

3

Page 16: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsEntanglementQuantum PhysicsEntanglement

Quantum entanglement occurs when particles such asphotons, electrons, molecules and even small diamondsinteract physically and then become separated.When a measurement is made on one of member of such a pair,the other member will at any subsequent time be foundto have taken the appropriate correlated value.

2

1

Entanglement is a challange in our understanding of natureog will hopefully give us new technological applications.

According to the Copenhagen interpretation of quantum physics,their shared state is indefinite until measured.

Page 17: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsObservation / Measurement - ClassicalQuantum PhysicsObservation / Measurement - Classical

A car (particle) is placed behind a person.The person with the car behind, cannot see the car.

The person turns around and observeres the car.

Classically we will say:The car was at the same place also just before the observation.

Page 18: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsObservation / Measurement - QuantumQuantum PhysicsObservation / Measurement - Quantum

A car is placed in the position Abehind a person.The person with the car behind,cannot yet observe the car.

The person turns aroundand observeres the carin the position B.

In quantum physicsit’s possible that the observation of a property of the carmoves the car to another position.

A

B

2

1

Page 19: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsObservation / Measurement - QuantumQuantum PhysicsObservation / Measurement - Quantum

Question:Where was the carbefore the observation?

Realist:The car was at B.

If this is true,quantum physics is incomplete.There must be some hidden variables (Einstein).

?

B

Orthodox:The car wasn’t really anywhere.

Agnostic:Refuse to answer.

It’s the act of measurementthat force the particle to ‘take a stand’.Observations not only disturb,but they also produce.

No sense to ask before a measurent.

Orthodox supported by theory (Bell 1964) and experiment (Aspect 1982).

Page 20: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsObservationQuantum PhysicsObservation

Before the measurement

After the measurement

1

2

M

M

Page 21: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

1Before the measurementthe position of the caris a superpositionof infinitely many positions.

The measurement producea specific position of the car.

A repeated measurementon the new systemproduce the same result.

1

22

M M

M

Quantum PhysicsObservationSuperposition

Quantum PhysicsObservationSuperposition

2

2

1

2

M

n

nnc 1

k2

1 2 ...

k

k

Page 22: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

1Quantum PhysicsSuperpositionFourier

Quantum PhysicsSuperpositionFourier

Music Pulse train

Heat Sampling

Page 23: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsClassical:Vector expanded in an orthonormal basis - I

Quantum PhysicsClassical:Vector expanded in an orthonormal basis - I

n

nneckcjcicV

321

nnn

nn

mmnn

nn

nmnn

nnmm

nnn

eVeV

Vec

cceececeVe

ecV

mnnm ee

nnn

nnn

eVe

ecV

V

1ei

2ej

3ek

V

11ec

22ec

33ec

Page 24: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsClassical:Vector expanded in an orthonormal basis - II

Quantum PhysicsClassical:Vector expanded in an orthonormal basis - II

n

nn eckcjcicV 321

nnn

nn

mmnn

nn

nmnn

nnmm

nnn

eVeV

Vec

cceececeVe

ecV

mnnm ee

nnn

nnn

eVe

ecV

V1ei

2ej

3ek

V

11 ec

22 ec

33 ec

v

c

c

c

cccvcccv

c

c

c

v

3

2

1*

3*

2*

1*

3*

2*

1

3

2

1

Complex coefficients

Page 25: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsState vector expanded in an orthonormal basisQuantum PhysicsState vector expanded in an orthonormal basis

n

nnc

nnn

nn

mmnn

nnmn

nn

nnmm

nnn

c

cccc

c

mnnm

nnn

nnnc

1

2

3

11 c

22 c

33 c

*

mnnm

Page 26: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsSpace - Dual spaceIntroduction

Quantum PhysicsSpace - Dual spaceIntroduction

A

A

1

12

*

21

2

21212121 AAAA

SpaceDual space

Ket

Bra

Page 27: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsSpace - Dual spaceExample - Real Elements

Quantum PhysicsSpace - Dual spaceExample - Real Elements

2

1

8

2

2312

2110

2

1

32

10A

21

82

32211201

31

2021

A

SpaceDual space

32

10A

31

20A

Ket

Bra

Page 28: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsSpace - Dual spaceExample - Complex Elements

Quantum PhysicsSpace - Dual spaceExample - Complex Elements

i2

1

i

i

i

ii

i

iA

62

22

2312

2)1(10

2

1

32

10

i21

ii

iii

iiA

6222

3221)1(201

31

2021

SpaceDual space

Bra

Ket

32

10 iA

31

20

iA

Ket

Bra

Page 29: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsSpace - Dual spaceExample - Scalar Product

Quantum PhysicsSpace - Dual spaceExample - Scalar Product

21

i

iiiiiii

i 7784214

12 ***

*

*

21

SpaceDual space

32

10 iA

31

20

iA

i4

12

21 i

i412

iiiiii

i 782412

4112

541222

2111

ii

ii

12

*

21 Ket

Bra

Page 30: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsSpace - Dual spaceExample - Operator I

Quantum PhysicsSpace - Dual spaceExample - Operator I

21

i

iiiii

ii

i

iii

i

iiAA

288)122(2)44(122

442

4312

4)1(102

4

1

32

1022121

SpaceDual space

32

10 iA

31

20

iA

i4

12

21 i

i412

iiii

i

iiii

i

iiAA

2884)7(144

174

4

132)1(220

4

1

32

1022121

212121 AAA Ket

Bra

Page 31: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsSpace - Dual spaceExample - Operator II

Quantum PhysicsSpace - Dual spaceExample - Operator II

21

i

SpaceDual space

32

10 iA

31

20

iA

i4

12

21 i

i412

iiiii

iAA

7432)1(220

32

10211

iiii

ii

iAA

747

4

23)1(

220

231

2011

111 AAA Ket

Bra

Page 32: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsSpace - Dual spaceExample - Operator III

Quantum PhysicsSpace - Dual spaceExample - Operator III

21

i

SpaceDual space

32

10 iA

31

20

iA

i4

12

21 i

i412

iiii

iiii

i

iA

iiii

ii

ii

iiAA

iiiii

ii

i

ii

i

iiA

2884)7(144

174

4

1

7

4

4

1

231

20

2884)7(144

174

4

174

4

1

32

102

288)122(2)44(122

442

122

44

24

1

32

10

2

21

2121

21

21

21

2121

A

A

AAKet

Bra

Page 33: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsProbability amplitudeQuantum PhysicsProbability amplitude

n

nnc

nn

nmmnnm

nmnmnm

nn

mm

ccccc2

,

*

,

*

1

1

mnnm

1 2

nn

nnn cc

12

nnc cn : Probability amplitude

cn2 : Probability

Normalization of a state vectordon’t changethe probability distributions.Therefore we postulate c and to represent the same state.

1

2

3

Same state

Page 34: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsProjection OperatorTheory

Quantum PhysicsProjection OperatorTheory

nn

nnnn

nnnP

n

nn

ofdirection in the

ofpart theprojects

operator Projection

nm

nmPPP

P

nnmmnnmnmnnmmnm

nnn

0

nnk

nknkk

knnkk

kknnnn cccc

22 c

Page 35: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsProjection OperatorExample - Projection to basisfunction

Quantum PhysicsProjection OperatorExample - Projection to basisfunction

nn

nnnn

nnnP

n

nn

ofdirection in the

ofpart theprojects

operator Projection

nnnn c

22 c

222

222

2211

1

02

2

0

2110

2010

2

1

10

00

10

00

1101

100010

1

0

2

1

20

01

2

0

0

1

1

02

0

11

cP

P

cc

Page 36: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsProjection OperatorExample - Projection to subroom

Quantum PhysicsProjection OperatorExample - Projection to subroom

nn

nnnn

nnnP

n

nn

ofdirection in the

ofpart theprojects

operator Projection

nnnn c

221112

2211

2

112

322211

0

1

0

2

0

0

1

1

0

2

0

0

0

1

0

2

1

3

2

1

000

010

001

000

010

001

100

1

0

0

010

0

1

0

001

0

0

1

3

2

1

3

0

0

0

2

0

0

0

1

1

0

0

3

0

1

0

2

0

0

1

1

ccP

P

ccc

nnn

2211 cc

Page 37: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsUnit OperatorTheory

Quantum PhysicsUnit OperatorTheory

In

nn

nnn

nnn

nnn

operatorunit an is

operator The In

nn

In

nn

1

2

3

Page 38: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsUnit OperatorExample

Quantum PhysicsUnit OperatorExample

In

nn

nnn

nnn

nnn

In

nn

1

2

3

I

cc

nnn

10

01

10

00

00

01

1101

1000

0010

011110

1

001

0

1

1

02

0

112211

Page 39: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsOrthonormality - CompletenessQuantum PhysicsOrthonormality - Completeness

In

nn

I

P

nnn

nnn

n

nnc

mnnm

nnnP

Orthonormality

Projection Operator

Completeness

1

2

3

Page 40: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsOrthonormality - CompletenessDiscrete - Continuous

Quantum PhysicsOrthonormality - CompletenessDiscrete - Continuous

In

nn

nnn

nnn

nnnc

mnnm

nnnP

Orthonormality

Projection Operator

Completeness

State

Discrete Continuous

)(

)(

dd

dcd

)'('

P

Id

I

P

nnn

nnn

Page 41: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsOperatorEigenvectors - Eigenvalues

Quantum PhysicsOperatorEigenvectors - Eigenvalues

Eigenvectors are of special interest since experimentally we always observethat subsequent measurements of a system return the same result (collapse of wave function).

Consequence of Spectral Theorem:

The only allowed physical results of measurements of the observable Aare the elements of the spectrum of the operator which corresponds to A.

k

A

k

A

nnc

21

11

k2 k2

A A

kkaA 1

Measured quantity

kkaA 1

Page 42: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsOperatorSelf-adjoint operator

Quantum PhysicsOperatorSelf-adjoint operator

AA

Def: Self-adjoint operator:

, * AA

The distinction between Hermitian and self-adjoint operatorsis relevant only for operators in infinite-dimensional vector spaces.

AA

Def: Hermitian operator:

***

AAA

AAA

AAProof:

Page 43: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsOperatorTheorem

Quantum PhysicsOperatorTheorem

nnnn

nnn

nnn

aAI

P

AA

AA

AA

21

*

1221

*

,

Theorem:

Proof:

AA

AA

i,baAiAiAiAi

,baAAAA

AbaAabAbAaA

AabAbaAbAaA

baba

*

1221

*

12

*

211221

*

12

*

211221

*

12**

21*

22

2

11

2*

12*

21*

22

2

11

2

2121

1for

11for

real

, , , arbitrary

Canceling i and adding

Page 44: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsHermitian operatorThe eigenvalues of a Hermitian operator are real

Quantum PhysicsHermitian operatorThe eigenvalues of a Hermitian operator are real

aa

aaaaaa

AA

AA

AA

AA

aA

AA

*

**

0

Theorem:

Proof:

The eigenvalues of a Hermitian operator are real.

aaaA

AA

*

Page 45: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsHermitian operatorEigenstates with different eigenvalues are orthogonal

Quantum PhysicsHermitian operatorEigenstates with different eigenvalues are orthogonal

21212112

211212

*

121212

*

1221

222111

if 0

0

aaaa

aa

aa

AA

aAaAAA

Theorem:

Proof:

Eigenstates corresponding to distinct eigenvaluesof an Hermitian operator must be orthogonal.

021

21

222

111

aa

aA

aA

AA

1

2

3

Page 46: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsOperatorexpanded by eigenvectors

Quantum PhysicsOperatorexpanded by eigenvectors

nnnn

nnn

nnn

aAI

P

n

nnc

nnn aA

nnnn

nnnn

nnnn

nnnn

nnnn

nnnn

nnn

nnn

aA

aaa

caacAccAA

n

n

a

A

seigenvalue

rseigenvecto

Operator

Every operator can be expandedby their eigenvectors and eigenvalues

Eigenvectors are of special interest since experimentally we always observe that subsequent measurements of a systemreturn the same result (collapse of wave function)The measurable quantity is associated with the eigenvalue. This eigenvalue should be real so A have to be a self-adjoint operator A+ = A

Page 47: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsAverage of Operator [1/2]Quantum PhysicsAverage of Operator [1/2]

n

nnc

n

nn caA2

AAA

Aa

aacaA

nnn

nnn

nnn

nnnn

nnnn

nnn

nnn

22

AcaAn

nn

2

Page 48: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsAverage of Operator [2/2]Quantum PhysicsAverage of Operator [2/2]

nn tct )()(

2

2

)(

)()(

tc

tcatAA

n

nn

)()(

)()(

)()(

)()(

)()(

)()(

)(

)()(

)()(

)()(

)()(

)()(

)(

)(

)(

)()( 2

2

2

2

tt

tAt

tt

tAt

tt

tAt

t

tAt

tt

tat

tt

tta

t

ta

tc

tcatA

nn

nn

nn

nn

nn

nn

nn

nnn

nn

nnn

n

nn

n

nn

n

nn tctA2

)()( AcaAn

nn

2

Page 49: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsDetermiate stateQuantum PhysicsDetermiate state

aA

aA

aA

aAaA

aA

AAA

0

02

22

aA

aA

Determinate state:A state prepared so a measurement of operator Ais certain to return the same value a every time.

The determinate state of the operator Athat return the same value a every timeis the eigenstate of A with the eigenvalue a.

Unless the state is an eigenstate of the actual operator,we can never predict the result of the operatoronly the probability.

Page 50: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsUncertainty [1/3]Quantum PhysicsUncertainty [1/3]

2

222

2*2222

222

2222

2222

2

1

2

1)Im()Im()Re(

fggfi

gfBA

zzi

zzzz

gfggffBA

ggBBBBBBBBB

ffAAAAAAAAA

AA

2

22 ,2

1

BA

iBA

Page 51: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsUncertainty [2/3]Quantum PhysicsUncertainty [2/3]

BABAfg

BAAB

BABAABAB

BABAABAB

BABAABAB

BAABBAAB

BBAABBAAgf

2

22 ,2

1

BA

iBA

Page 52: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsUncertainty [3/3]Quantum PhysicsUncertainty [3/3]

BABA

BAi

fggfi

gfBA

BABAABBAABfggf

BABAfg

BAABgf

,2

1

,2

1

2

1

,

22222

BABA ,2

1

Page 53: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsKinematics and dynamicsQuantum PhysicsKinematics and dynamics

Necessary with correspondence rulesthat identify variables with operators.

This can be done by studying specialsymmetries and transformations. aA

Operator Variable

The laws of nature are believed to be invariantunder certain space-time symmetry operations,including displacements, rotations,and transformations between frames of reference.

Corresponding to each such space-time transformationthere must be a transformation of observables,opetators and states.

Energy, linear and angular momentumare closely related to space-time symmetry transformations.

'

'

'

AA

aa

a A 'a 'A '

T

Page 54: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsNoether’s theoremQuantum PhysicsNoether’s theorem

Symmetry Conservation

Time translation Energy ESpace translation Linear momentum pRotation Angular momentum L

Noether’s (first) theoremstates that any differentiable symmetry of the action (law) of a physical systemhas a corresponding conservation law.

Page 55: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsInvariant transformationUnitary operator

Quantum PhysicsInvariant transformationUnitary operator

IUU

UUUU

I

cc

c

c

U

nnn

nn

nn

nn

nn

nn

''

''

'

'''

'

22

IUU

Any mapping of the vector space onto itselfthat preserves the value of |<|>|may be implemented by an operator Ubeing either unitary (linear) or antiunitary (antilinear).

2222)(

dU

dU

ddUdU

Only linear operatorscan describe continous transformations.

U

'

The laws of nature are believed to be invariantunder certain space-time symmetry.Therefore we are looking for a continous transformationthat are preservering the probability distribution.

22'nn cc

Page 56: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsUnitary operatorQuantum PhysicsUnitary operator

1

1

111

'

'

'

''''

'''

'

UAUA

AUAU

AaUUaUaUUAU

UaaAUA

aA

aA

U

nnnnnnnn

nnnnnn

nnn

nnn

nn

1' UAUA

Any mapping of the vector space onto itselfthat preserves the value of |<|>|may be implemented by an operator Ubeing ether unitary (linear) or antiunitary (antilinear).

Only linear operators can describecontinous transformations.

2222)(

dU

dU

ddUdU

Only linear operatorscan describe continous transformations.

Page 57: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsGenerator of infinitesimal transformationQuantum PhysicsGenerator of infinitesimal transformation

iKs

ss

ss

s

s

s

s

esU

iKsUds

sdU

sUds

dsUssU

s

sUsUssU

KKiKds

dU

ds

dU

ds

dU

sOds

dU

ds

dUsIUUI

sOds

dUIsU

)(

)()(

)()()(

)()()(

)(

)()(

1

0

22

1

0

212

2121

0

0

2

0

2

0

1

22

iKsesU )(

Any mapping of the vector space onto itselfthat preserves the value of |<|>|may be implemented by an operator Ubeing ether unitary (linear) or antiunitary (antilinear).

Only linear operators can describecontinous transformations.

Page 58: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsTime operator - Time dependent Schrödinger equationEnergy operator - Generator for time displacement

Quantum PhysicsTime operator - Time dependent Schrödinger equationEnergy operator - Generator for time displacement

)()(

)()(

)()()()(

)()()()()(

)()()(

2

22

tHtt

hi

tHh

it

t

HOtHh

itTt

HOtHh

ittaOH

h

iI

tetDTtH

h

i

T

Ht

hi

Vm

pH

2

2

Energy operatorGenerator for time displacement

Page 59: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsSchrödinger EquationTime dependent / Time independent

),(

),(),(2

22

t

trhitrtrV

m

h

thiH

EVm

h

2

2

2

)(

)(

1)()(

2)(

1

)()()()(

2)(

)()()()()(2

)()(),(

)(

22

22

22

Et

t

thirrV

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Page 60: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsSchrödinger equation - Time independentQuantum PhysicsSchrödinger equation - Time independent

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Page 61: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsNormalization is time-independentQuantum PhysicsNormalization is time-independent

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Page 62: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

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Page 63: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsSchrödinger equation - Time independentQuantum PhysicsSchrödinger equation - Time independent

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Page 64: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

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Page 65: Quantum Physics Mathematics. Quantum Physics Tools in Real Life Reality.

Quantum PhysicsUncertaintyPosition / Momentum - Energy / Time

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