Poisson Brackets - Classical Mechanics - Lecture Slides, Slides of Classical Mechanics

These main points are discussed in these Lecture Slides : Poisson Brackets, Matrix Form, Single Set, Hamilton’s Equations, Symplectic, Return the Lagrangian, Dynamical Variable, Angular Momentum, Two Dimensional Harmonic, Oscillator

Typology: Slides

2012/2013

Uploaded on 07/24/2013

janam
janam 🇮🇳

5

(1)

83 documents

1 / 9

Toggle sidebar

This page cannot be seen from the preview

Don't miss anything!

bg1
PoissonBrackets
Docsity.com
pf3
pf4
pf5
pf8
pf9

Partial preview of the text

Download Poisson Brackets - Classical Mechanics - Lecture Slides and more Slides Classical Mechanics in PDF only on Docsity!

Poisson

Brackets

Matrix

Form

•^

The

dynamic

variables

can

be

assigned

to

a

single

set.

q^1

,^ q

, …, 2

qn

,^ p

, 1 p

, …, 2

pn

z^1

,^ z

, …, 2

z

2 n

•^

Hamilton’s

equations

can

be

written

in

terms

of

z



Symplectic

2

n^

x^

2 n

matrix

Return

the

Lagrangian

0^ I
I
J



^

z

t z H

J

z^

j j

j j^

q p

d dt

t z H

q p

t z H z J z t z z L

  

Angular

Momentum

Example •^

The

two

dimensional

harmonic

oscillator

can

be

put

in

normalized

coordinates.

m

=

k

=

1

•^

Find

the

change

in

angular

momentum

l

It’s

conserved

^

^

^

(^21) 1 2

(^22)

(^21)

1 2

q

q

p

p

H

1 2

2 1

p q

p q l^

q q q q p p p p

dl dt

H q l p

H p l q

dl dt

H z

J

l z

dl dt

i

i

i

i

 

Docsity.com

Poisson

Bracket

•^

The

time

‐independent

part

of

the

expansion

is

the

Poisson

bracket

of

F

with

H
•^

This

can

be

generalized

for

any

two

dynamical

variables.

•^

Hamilton’s

equations

are

the

Poisson

bracket

of

the

coordinates

with

the

Hamitonian.

(^1) S

^

 ^

H z

J

F z

H
F

^

 ^

B z

J

A z

B
A

i

i

i

i^

A q

B p

B p

A q

B
A

^

H

z

H z

J

z z

z^

  

^

Poisson

Properties

•^

In

addition

to

the

Lie

algebra

properties

there

are

two

other

properties.^ –

Product

rule

Chain

rule

•^

The

Poisson

bracket

acts

like

a

derivative.

,^

C A B C B A

BC

A



 ^

J

z z^

^

 

B z

J

A z

t

B t

A

 

  

B z J z A B A

^

^

^

 

^

B
A
B
A

Poisson

Bracket

Theorem

•^

Let

z

t )

describe

the

time

development

of

some

system.

This

is

generated

by

a

Hamiltonian

if

and

only

if

every

pair

of

dynamical

variables

satisfies

the

following

relation:

^

^

^

^

 B A B A B A

d dt

^
,^

^

^

^

^

 B A t H B A B A

d dt

,^

^

^

^

^

^

 H B A B H A H B A

,^

^





 

 



  

  

  

 

   





 

 

  

 

B^ t

A

B A t

t z

B

J A z

B z

J t z

A

B z

J A z

t

B A t

,

, ,

2

2

 



 