, Lec 1 : Introduction 04/10/22
Symmetry Principles
↑
·
change smth but doesn't change (i rotating square 90 %
. e
#⑪evenbetterasitdoest
1) Laws of
physics invariant .t
w r .
location
Nother's Theorem research bit (not successful 101)
Emmy
-s a
↳ifI have symmprinciple cons lawy
accompanying
>
-
.
= conservation of momentum
(ans that
· laws of physics do not depend on where you are
5
2) Laws of
physics invariant w r
. .
t time
=> conservation of
energy
3) Laws of physics -
11-orientation
conservation of
angular momentum
=
, either frame can be declared as "Stationary"
all that matters relatively
S is
they to
=
* more
each other
-
1) Laws of
physics invariant w r . .
t uniform relative motion
↳ relative
velocity constant
⑭
=
x G
= Q &
·, relative acceleration = O between frames
t+)
A
event measured & we get special case of relativity
train observer
by
which frame of ref is
* no ABSOLUTE standard of rest
=>
in motion up to us
Coordinate systems Lie .
w/ Earth etc )
platform
"Stationary moving along
:
,
orientate co-ordinate systems fit to reduce
complexity of problem
>
-
>
can our as we see
> can
-
"zero" our co-ordinate system) for convenience
>
"zero" time for our convenience
-
can
"Galilean Transformation"
>
-
translation btw S and
...... Withtrain
S'Coordinate dinate continuously insensing
as seen in a
S
3= x' + vtdistance it goes in frame
·
at some
point train t platform will
allig an x-axis
↓
Event 1 0 x= 0 t t 0
,
: =
x = = 0
,
,
in atto
des same disease
Gx x =
laser
beam
at same
speed
, if have observer ?
train speed u' how fast
according to
·
passenge
we on
, ,
U'
U =
Y
+
No velocity btw two frames
observer in S
speed of
wir.t train
Maxwell's equations predict speed of light (electromagnetism related)
·
* <
= no Y should not depend on URM
. .
= CONTRADICTION W/ "Galilean Transformation"
↳
equations tell us how E & B fields act moving E can induce B field ,
and viceversa > loop -
self-propagating wave of
electromagnetism
Elight
, ~
Schange in B- changes E
> changes
speed
-
Michelson Morley could be affected
Exp =
thought lightwave by "aether wind"
-
,
>
-
disturbance aether like wh of air
· >
-
no
change in speed of light was recorded
by interferometer
46 months apart
·
if there is
any
effect of relative motion , affecting speed of light we should be able to detect it ?
·
measure > by combining light beams looking for changes interference
in pattern
> months later when
does observed change when Earth goes one
way compared to moving in opposite direction in orbit
·
<
=>if both Maxwell and Galileo are correct then thee should be diff in <
postulatrelativity
2) "("invariant w r.
.
t uniform relative motion
in
>
-
0 . 9C
-
------
-
L C
·
observer still sees
'c'travelling at same
speed
Symmetry Principles
↑
·
change smth but doesn't change (i rotating square 90 %
. e
#⑪evenbetterasitdoest
1) Laws of
physics invariant .t
w r .
location
Nother's Theorem research bit (not successful 101)
Emmy
-s a
↳ifI have symmprinciple cons lawy
accompanying
>
-
.
= conservation of momentum
(ans that
· laws of physics do not depend on where you are
5
2) Laws of
physics invariant w r
. .
t time
=> conservation of
energy
3) Laws of physics -
11-orientation
conservation of
angular momentum
=
, either frame can be declared as "Stationary"
all that matters relatively
S is
they to
=
* more
each other
-
1) Laws of
physics invariant w r . .
t uniform relative motion
↳ relative
velocity constant
⑭
=
x G
= Q &
·, relative acceleration = O between frames
t+)
A
event measured & we get special case of relativity
train observer
by
which frame of ref is
* no ABSOLUTE standard of rest
=>
in motion up to us
Coordinate systems Lie .
w/ Earth etc )
platform
"Stationary moving along
:
,
orientate co-ordinate systems fit to reduce
complexity of problem
>
-
>
can our as we see
> can
-
"zero" our co-ordinate system) for convenience
>
"zero" time for our convenience
-
can
"Galilean Transformation"
>
-
translation btw S and
...... Withtrain
S'Coordinate dinate continuously insensing
as seen in a
S
3= x' + vtdistance it goes in frame
·
at some
point train t platform will
allig an x-axis
↓
Event 1 0 x= 0 t t 0
,
: =
x = = 0
,
,
in atto
des same disease
Gx x =
laser
beam
at same
speed
, if have observer ?
train speed u' how fast
according to
·
passenge
we on
, ,
U'
U =
Y
+
No velocity btw two frames
observer in S
speed of
wir.t train
Maxwell's equations predict speed of light (electromagnetism related)
·
* <
= no Y should not depend on URM
. .
= CONTRADICTION W/ "Galilean Transformation"
↳
equations tell us how E & B fields act moving E can induce B field ,
and viceversa > loop -
self-propagating wave of
electromagnetism
Elight
, ~
Schange in B- changes E
> changes
speed
-
Michelson Morley could be affected
Exp =
thought lightwave by "aether wind"
-
,
>
-
disturbance aether like wh of air
· >
-
no
change in speed of light was recorded
by interferometer
46 months apart
·
if there is
any
effect of relative motion , affecting speed of light we should be able to detect it ?
·
measure > by combining light beams looking for changes interference
in pattern
> months later when
does observed change when Earth goes one
way compared to moving in opposite direction in orbit
·
<
=>if both Maxwell and Galileo are correct then thee should be diff in <
postulatrelativity
2) "("invariant w r.
.
t uniform relative motion
in
>
-
0 . 9C
-
------
-
L C
·
observer still sees
'c'travelling at same
speed
