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#49743 - 09/17/13 12:58 PM Transmission of light thru a media
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
A rather strange and bizarre conversation with Newton reminded me of probably my first great mystery I ever first puzzled at in science.

It was one of those moments in life that you remember as if it was yesterday.

I was a young student and this was my first real science problem I had encountered that I could not answer and any answer given to me by teachers and books I could easily falsify.

The problem was simple and you may care to follow

1.) We know and can measure that light is slowed in certain transparent media like air, water and glass.

2.) So if you make the glass or water thicker surely the light must slow more and more like stopping a bullet with jelly all one needs is enough thickness of jelly and the bullet will stop. I thought I was onto something with this because the deep oceans were also dark so a certain amount of water seems to be able to stop light in the above prediction.


However there is a big problem the speed of light is quoted as an absolute number and in fact it is used to create the refractive index

refractive index = speed of light in vacuum / Speed of light in media

Vacuum: 299,792,458 meters per second ... refractive index 1.000

Air at STP: 298,925,574 meters per second ... refractive index 1.000293

Typical crown glass: 197,231,880 meters per second .... refractive index 1.52

Water at 20 C: 225,407,863 meters per second .... refractive index 1.33


So I thought there is something wrong with these numbers how can they be quoting absolute speeds without telling me the thickness.


I was so certain they had to be wrong I searched for the answer to the question how thick a piece of glass, air and water is required to completely stop light travelling thru it.


My problem was compounded because when I took the problem to my science teacher they offered a strange answer which itself was ultimately wrong.


The answer teacher gave:

Light is slowed in a media by the atoms absorbing the photons as they pass thru, a small delay later the photon is released back on it's way so the light passes thru but it appears slightly slower. There is no thickness of glass, air or water that will stop the light and that is why there is no thickness quoted.


Obviously wrong:

There is an obvious falsification to the above. If atom absorption was involved only very specific frequencies matching the spectral lines of the atoms would be affected. The ability to slow the entire spectrum of visible light for example would be almost impossible for a media.

It also was obvious to me if what they said was true I should be able to bend light easily by putting a round jar full of water for example on a record turn table and pass a light thru the turning media. As the photon gets absorbed when it is re-emitted the photon would be slightly moved in the spin direction and each time the process happened you should be able to bend the light. I actually tried it years later with a laser and a high speed centrifuge and nope the light goes straight thru.


A few years later I was to learn the answer to my problem and it is among the most amazing behaviors of light and once the answer is known one never thinks of light thru a media quite the same again.


So open challenge anyone care to offer ideas on the transmission of light thru a media and my childhood problem ... Lets see if anyone knows the answer ... warning google it will probably get you the wrong answer laugh


God luck
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#49745 - 09/17/13 03:57 PM Re: Transmission of light thru a media [Re: Orac]
paul Offline
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Registered: 03/21/06
Posts: 4136
how to bend light!




in water and sugar layers




in water


in plastic



in glass



_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#49748 - 09/18/13 01:04 AM Re: Transmission of light thru a media [Re: paul]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Cool videos Paul and in a fibre optic cable you can tie it in knots and it will travel thru it but that is just the light tube feature of light in operation.

However none of this has really tells you anything about the how light transmission occurs and why these weird effects occur which is the question we are after.
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I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#49755 - 09/18/13 03:25 PM Re: Transmission of light thru a media [Re: Orac]
paul Offline
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Registered: 03/21/06
Posts: 4136
I was just putting up a few interesting videos about
the bending of light , I wasnt intending for the videos to
serve as a answer to your question.

I do have a few questions about your centrifuge experiment however.

centrifuge diameter.
centrifuge speed.
transmission medium. (water , mixture, etc)

did you adjust the laser to different radius while the centrifuge was turning, etc.

did you examine the light inside the centrifuge?

did you try this through a rotating gas?

did you try different speeds?

ie, did the light slow down more while passing through the higher pressurized fluid than through a lower pressurized fluid in the centrifuge?

lots of questions.

try this through water and a vertical laser (top to bottom) locate your pickup sensors inside the centrifuge.

this removes the transmission through the centrifuge bowl.

turn it slow then increase speed.

then try different radius from center for pressure increases.

it should bend the light.right?

Im thinking the light in your experiment might have transmitted through and around the bowl you used and didnt
travel straight through the medium you used.

perhaps.

_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#49758 - 09/19/13 02:27 AM Re: Transmission of light thru a media [Re: paul]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Originally Posted By: paul

centrifuge diameter.
centrifuge speed.
transmission medium. (water , mixture, etc)


Long time ago but it was a standard science centrifuge generally they do something like 15000-20000 RPM max. I bought it from the uni they were replacing it and I removed the outside casing and removed the central cradle. I then had a round metal plate made up that clamped a standard large science beaker with lid in the centre and had it balanced by a workshop on a machine that balanced turbocharger fans. I then put the rig ontop of the spindle shaft of the centrifuge.


So you can probably guess by all that effort I thought I was about to rewrite physics.

It all failed dismally smile


Originally Posted By: paul

did you adjust the laser to different radius while the centrifuge was turning, etc.


I did everything I was certain it would do something different and it all behaves exactly the same as the beaker not moving (one of your videos is light going thru a round beaker).


Originally Posted By: paul

did you examine the light inside the centrifuge?


That was actually what I was most measuring I had the laser clamped and from above was measuring the refraction angle because you could see the beam thru the spinning beaker and record it.

It is all rather boring whatever it looks like prior to the spin it looks like after spinning except.


Originally Posted By: paul

did you try this through a rotating gas?

did you try different speeds?


I tried a oxygen, nitrogen, neon, helium gases. For liquids I used water, ethane, toluene and any homogenous liquids I could get my hands on because obviously if the liquid is a mixture the centrifuge will produce an effect because it will change densities between middle and outer.


Originally Posted By: paul

ie, did the light slow down more while passing through the higher pressurized fluid than through a lower pressurized fluid in the centrifuge?


Nope I didn't try anything with pressure I was very disappointed in the end as you may have guessed.


Originally Posted By: paul


try this through water and a vertical laser (top to bottom) locate your pickup sensors inside the centrifuge.

this removes the transmission through the centrifuge bowl.

turn it slow then increase speed.

then try different radius from center for pressure increases.

it should bend the light.right?



Didn't try it but I can predict what will happen absolutely nothing!!!!


Originally Posted By: paul

Im thinking the light in your experiment might have transmitted through and around the bowl you used and didnt
travel straight through the medium you used.


That is what I was expecting as well Paul it doesn't happen and as I later learnt there is a reason the light doesn't actually travel in the medium at all.

I will give you the answer via an experiment I did many years later.

Here is the background to the experiment.

Look at the image of a laser going thru a solid plastic block from above



What you notice is the light changes angle the moment it hits the surface of the block.

Now a thought experiment for you keep making the block thinner and thinner until it is the thickness of plastic lunch wrap.

Will it still refract the laser beam?

Lets go one further lets take the thickness down till we have a layer one atom thick will it still refract the laser beam?


I will wait for your answer but I will give you what I expected to happen with a one atom thick wall which light passed thru was it would sometimes refract the beam if it hit an atom and sometimes not and pass straight thru. That is the natural expectation but it is not what happens .. can you guess what happens?
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I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#49759 - 09/19/13 04:23 AM Re: Transmission of light thru a media [Re: Orac]
paul Offline
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Registered: 03/21/06
Posts: 4136
Quote:
can you guess what happens?


by thinning the block nothing happens , unless the block becomes
smaller than the beam.

in which case the light entering the block is only less.


the problem with the experiment is that it is too small.

lets increase its size.

lets make it 93 million miles from the center of the centrifuge.

so that light from the center would take apx 8 minutes to reach the perimeter of the bowl.

like our suns light hitting the earth.

instead of using the sun we use a hand held laser.

and the laser is rotating , the light from the laser will
look as if it were bending if viewed from above.

lets reverse this , if we put the laser 93 million miles from the center of the bowl and point it at the center and let the laser orbit the center , it still takes apx 8 minutes for the laser light to reach the center.

looking at the laser beam from above the light will look as if its bending as it travels.

but all of the light is moving away from the center at a right angle to the center.

motion and time becomes involved.

like pointing directly at a moving target and trying to hit it
you will never hit the target.

if the space between the earth and the sun were made of glass
then the time would be greater than the 8 minutes because the glass would slow down the light waves.

which brings us back to the thickness in your first post.

does thickness of a medium matter?

on a sunny day is there light 1 mile down on the sea floor?

of course thickness matters.

light slowed down to the speed of a bicycle



now if the bose einstein condensate were rotating , the light
would exit the condensate at a different angle than it entered , it could even be sent backwards.


_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#49760 - 09/19/13 08:08 AM Re: Transmission of light thru a media [Re: paul]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
I am not sure what to even make of or answer to that it's a mix of different statements smile
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I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#49765 - 09/19/13 05:03 PM Re: Transmission of light thru a media [Re: Orac]
pokey Offline
Member

Registered: 08/22/07
Posts: 84
Quote:
Lets go one further lets take the thickness down till we have a layer one atom thick will it still refract the laser beam?

In my opinion, yes. The refraction occurs right at the boundary layer.


Quote:
...and as I later learnt there is a reason the light doesn't actually travel in the medium at all.

Are you saying that the photon that first touches the medium is not the one that "exits" the medium?

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#49766 - 09/19/13 05:49 PM Re: Transmission of light thru a media [Re: pokey]
paul Offline
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Registered: 03/21/06
Posts: 4136
Orac

do you think that the bose einstein condensate slows light down?

and if so , dont you think that if the condensate were rotating
the light would exit the condensate at a different angle than it
entered?

Pokey

Quote:
In my opinion, yes. The refraction occurs right at the boundary layer.


that is the way that light travels through a medium.
light angle to boundary layer --> refraction angle --> exit angle same as entry angle (parallel).


Quote:
Are you saying that the photon that first touches the medium is not the one that "exits" the medium?


this is getting interesting.
from what I understand its not the same as the one that entered , because photons are emitted through excitement.

the atoms get excited by photons entering the medium then they emit photons.etc...etc...etc... then the light exits the medium.



_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#49768 - 09/19/13 08:31 PM Re: Transmission of light thru a media [Re: paul]
Bill Offline
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Registered: 12/31/10
Posts: 1858
Loc: Oklahoma, USA
Originally Posted By: Paul
this is getting interesting.
from what I understand its not the same as the one that entered , because photons are emitted through excitement.

the atoms get excited by photons entering the medium then they emit photons.etc...etc...etc... then the light exits the medium.

No, I think Orac mentioned that idea, and that it is not correct. The electrons in an atom can absorb radiation only at specific wavelengths. Each atom absorbs a discrete set of wavelengths. So with a white light the only wavelengths of light that would be affected would be the ones that corresponded to the wavelengths that the molecules in that substance could absorb. The index of refraction does depend somewhat on wavelength, that's why you get a refraction pattern when you shine a white light through a prism. But if it was being absorbed and re-emitted it wouldn't work for all wavelengths.

Bill Gill
_________________________
C is not the speed of light in a vacuum.
C is the universal speed limit.

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#49769 - 09/20/13 12:13 AM Re: Transmission of light thru a media [Re: Orac]
newton Offline
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Registered: 09/30/12
Posts: 1209
"now if the bose einstein condensate were rotating , the light
would exit the condensate at a different angle than it entered , it could even be sent backwards"


Michelson Morley and above

Omega = V line /Radius


Line velocity of the Earth aslo can be measure

Light --->(bose einstein condensate)----> out light ----> 30km/s

Beam shape I mean " beam angle must rise up " slower or opposite to 30 km/s faster

( sorry for my English )

Beam shape for example entry is 2r angle( below picture ) exit is (3r) ( we schould see + and - 30 km /s different )



Rotation info (now if the bose einstein condensate were rotating , the light
would exit the condensate at a different angle than it entered)

+ Line velocity ( beam's angle shape ) = all what we need to evaluate absolute Earth Velocity

( Michelson Morley inside bose einstein condensate) ???

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#49770 - 09/20/13 01:53 AM Re: Transmission of light thru a media [Re: pokey]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Originally Posted By: pokey

In my opinion, yes. The refraction occurs right at the boundary layer.



The correct answer is slightly before the boundary layer because the electromagnetic wave and the electrons react a small distance ahead.


Originally Posted By: pokey

Are you saying that the photon that first touches the medium is not the one that "exits" the medium?


The photon never exists in the media at all in techno speak

Quote:

Light traveling within a medium is no longer a disturbance solely of the electromagnetic field, but rather a disturbance of the field and the positions and velocities of the charged particles (electrons) within the material.


I will get to the proof of this when I answer some of the next answers .. follow along


Edited by Orac (09/20/13 02:15 AM)
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#49771 - 09/20/13 01:56 AM Re: Transmission of light thru a media [Re: paul]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Originally Posted By: paul
Orac
do you think that the bose einstein condensate slows light down?


I thought you didn't believe in QM so how can a BEC exist ... just stirring smile

Anything with electrons will slow light down and I will show you the proof in a second ... science has a proof!


Originally Posted By: paul

and if so , dont you think that if the condensate were rotating
the light would exit the condensate at a different angle than it
entered?


Refraction occurs wherever there are elctrons in space that light encounters that is all the light sees is the charge it doesn't see the atom or matter or media as anything but that and again I will ask you hang in the same as pokey and I will show you the proof.
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#49772 - 09/20/13 02:14 AM Re: Transmission of light thru a media [Re: Orac]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Transmission of light from a modern perspective:

Electromagnetic waves including light the same as all the fundamental fields would usual pass straight thru matter. The only reason light reacts with matter is because electromagnetic waves including light react with the charge in matter it becomes like a shockwave.


The ultimate proof of that can be done by using QM trickery called electrically induced transparency

http://en.wikipedia.org/wiki/Electromagnetically_induced_transparency

You can make a material that normal will not allow light to pass thru it to allow it thru over a very narrow window band.

Layman articles:
http://arstechnica.com/science/2012/03/f...tack-using-eit/
http://www.wired.com/wiredscience/2011/09/electromagnetic-induced-transparency/


The full layman reference on the matter:
http://en.wikipedia.org/wiki/Slow_light


Why this subject still causes confusion and is not easily picked up on google searches is because the definitive answers are all post 1999, it takes time for such changes to make it through all levels of science.


That is the point the idea of light wave duality died, light is only ever a wave the particle behavior of light is an illusion creted by the disturbance of the field in the presence of charge (electrons).


The correct and more accurate view of light is quoted

Quote:

The simplest picture of light given by classical physics is of a wave or disturbance in the electromagnetic field. In a vacuum, Maxwell's equations predict that these disturbances will travel at a specific speed, denoted by the symbol c. This well-known physical constant is commonly referred to as the speed of light. The postulate of the constancy of the speed of light in all inertial reference frames lies at the heart of special relativity and has given rise to a popular notion that the "speed of light is always the same". However, in many situations light is more than a disturbance in the electromagnetic field.

In addition to propagating through a vacuum, light may also propagate through many types of matter, denoted as the medium. Light traveling within a medium is no longer a disturbance solely of the electromagnetic field, but rather a disturbance of the field and the positions and velocities of the charged particles (electrons) within the material. The motion of the electrons is determined by the field (due to the Lorentz force) but the field is determined by the positions and velocities of the electrons (due to Gauss' law and Ampere's law). The behavior of a disturbance of this combined electromagnetic-charge density field (i.e. light) is still determined by Maxwell's equations, but the solutions are complicated because of the intimate link between the medium and the field.



That is the lesson and memo in the question I posed.

Newtons problems stem from the fact he equates light in a vacuum to light in a media and that assumption is wrong ... one needs to be careful about assumptions smile

He shouldn't feel bad that was my problem as well in my initial experiment and why it failed dismally .. so I was definitely no smarter but I did learn laugh

There is a small message in the experiment for those who still want a solid world anything that looks solid with a bit of QM trickery we can make transparent to light so your world really is a "glass house" take care in every sense smile

So many lessons from one piece of basic science!

Paul won't like it or accept it because it involves QM so even proof by doing what in classic physics seems impossible ... mind you we have him accepting BEC exists he probably didn't realise what it is ... queue predictable reaction ... uncontrolled rant incoming laugh


Edited by Orac (09/20/13 05:00 AM)
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#49776 - 09/20/13 04:54 AM Re: Transmission of light thru a media [Re: Orac]
newton Offline
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Registered: 09/30/12
Posts: 1209
Below my test proposition inside LIGO pipe

if somone know staff please call them we can use small laser
we need only vacuum ( zero dolars investition )

Below pictures and idea I made on two days after my test with photocamera


IDEA EXPLAIN ( Vacuum )

SHOT no 1
----light----> [pipe 4 km (2.5 )miles ] --> 30 km/s
(1/300 000 sec)
we turn on and
off hot laser
for very short time

Shot no 2 the same light signal but ( 6 h later )
pipe will be ideal perpendicular to 30 km/s


( what is happen inside pipe )? light need for distance 4 km
4/300 000 s
( 1/300 000 s ) we turn on/off hot laser ( I designed special
shoter like in photocamera only 1/300 000 s )

3/300 000 s ?

after we turned off laser
light signal = beam that is long 1 km
and we know that beam is inside pipe

Earth around SUN 30 km/s = that pipe is mving with Earth
what about 1 km long beam inside pipe ???

3/300 000 s and 30 km/s = 30 000 000 mm/s schoud give at the end of pipe different between position where light entry to pipe and exit from pipe

REAL TEST IN LIGO PROPOSITIONS ( we can made )
sorry for my english

http://tesla2.blogspot.com/

I wait for peole who want to confirm above Michelson Morley test but beam long 1 km Vacuum and beam inside pipe that is moving perpendicular to beam !!!!

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#49777 - 09/20/13 05:02 AM Re: Transmission of light thru a media [Re: newton]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
Sure Newton don't let facts and experimental results get in the way of your theory laugh
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I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#49778 - 09/20/13 05:08 AM Re: Transmission of light thru a media [Re: Orac]
newton Offline
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Registered: 09/30/12
Posts: 1209
STEP 1
calibration we wait for earth position
30 km/s must be parallel to our pipe

we make master shot ( perfect to center -end of pipe )



Situation after step 1 ( before step 2 )




Step 2
Laser is hot ( we wait 6 h ... 6 h later we know that 30 km/s is perpendicular to laser ( laser was set 6 h before )



blue element is bloking hot laser and we wait for start
( blue element will open / close only for 1/300 000 s)


STEP 2
SHOT !!!! ( at the end of pipe we have sensor similar to camera chip - this sesor is able register light position )



BEFORE BEAM INSIDE PIPE 3/300 000 sec ???

( for me it will look like very old video game )




author
Maciej Marosz
Engineer and Inventor
http://tesla4.blogspot.com/

my first test I started 1 year ago above pipe we can exchange for dark dark filtre and camera

important info ( not exist ideal line - laser always have some angle )



It is new version Michelson Morley test but my Version without any problem can read WEST - East

I have only one problem I live in small polish town ( getto )
and I not have condition for test !!!

http://solarsytemspeed.blogspot.com/


Edited by newton (09/20/13 05:16 AM)

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#49779 - 09/20/13 05:15 AM Re: Transmission of light thru a media [Re: newton]
Orac Offline
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Registered: 05/20/11
Posts: 2819
Loc: Currently Illinois, USA
The experiment will fail dismally assuming the tube is a vacuum it will do something even weirder than you think if the tube contains a media like air and you will have to be careful about what the tube is built from laugh

The problem with actually doing the experiment is dealing with micro movements, expansion/contraction with temperature and geomagnetic induction over such a long distance. The whole setup is actually completely crazy to try and control, you do a much more precise test with smaller easier setups with a quantum dot but that would require learning which isn't your strong point Newton. I like your optimism on the size of the laser dot on the target over a 4km distance smile

I would do the experiment for you to show how silly it is newton but it's completely impractical.

It is rather easy to work out what will happen you choose not to try and understand smile


Edited by Orac (09/20/13 06:00 AM)
_________________________
I believe in "Evil, Bad, Ungodly fantasy science and maths", so I am undoubtedly wrong to you.

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#49780 - 09/20/13 03:09 PM Re: Transmission of light thru a media [Re: Orac]
paul Offline
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Registered: 03/21/06
Posts: 4136
Orac

Quote:
So many lessons from one piece of basic science!

Paul won't like it or accept it because it involves QM so even proof by doing what in classic physics seems impossible ... mind you we have him accepting BEC exists he probably didn't realise what it is ... queue predictable reaction ... uncontrolled rant incoming


if I like it or not means nothing.

I used the bose eienstein condensate because it shows that light can be slowed drastically in a small experiment.

if the experiment claims to only exist due to the proposed reality of QM being a factual means of calculations
used to predict that is based on fantasy then that also means
nothing.

the point here is that light was slowed by the condensate.

and if the condensate were contained inside your centrifuge experiment the light would exit at a different angle.

theres no question about that.

but the same result can be achieved using a larger experiment
that has nothing to do with fantasy such as QM.

all the bose einstein condensate does is reveal that a larger
experiment can be performed with the exact results.
_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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#49781 - 09/20/13 03:38 PM Re: Transmission of light thru a media [Re: Bill]
paul Offline
Megastar

Registered: 03/21/06
Posts: 4136
Bill

Quote:
No, I think Orac mentioned that idea, and that it is not correct.


let me guess , so your saying that the photons that enter the
medium are the same photons that exit the medium.

is that what your saying?

so basically your saying that the light that exits the medium
does not interact with the medium at all , correct.

if so then why does the speed of light decrease through a medium?

I still say that photons entering a medium excite the atoms in the medium and the atoms emit photons and this interaction is why the speed of light decreases through a medium.

diamonds = 2.14 ri

glass = 1.5 ri

diamonds more dense than glass = more interaction.

as in... sometimes you can still find the sensible stuff
if you look long enough , it hasnt been covered up completely
to satisfy the new fantasy disciplines in science.

Quote:
The speed of light in a vacuum is always the same, but when light moves through any other medium it travels more slowly since it is constantly being absorbed and reemitted by the atoms in the material. The ratio of the speed of light in a vacuum to the speed of light in another substance is defined as the index of refraction (aka refractive index or n) for the substance.


http://www2.ups.edu/faculty/hanson/labtechniques/refractometry/theory.htm

Originally Posted By: paul
this is getting interesting.
from what I understand its not the same as the one that entered , because photons are emitted through excitement.

the atoms get excited by photons entering the medium then they emit photons.etc...etc...etc... then the light exits the medium.


YES!

also , lets not forget temperature as temperature causes a medium to become less dense or more dense , so the speed of light is slightly faster through a hotter medium and slightly slower through a colder medium.

and pressures cause temperature increases and vacuums cause
temperature decreases.

its all classical physics.

_________________________
3/4 inch of dust build up on the moon in 4.527 billion years,LOL and QM is fantasy science.

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