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Author Topic: Does Light Age & Fade Away ?  (Read 3970 times)

neilep

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Does Light Age & Fade Away ?
« on: 19/08/2011 16:13:48 »

Dearest Lightologists ,

As a Sheepie I of course luff light. Light is my all time favourite thing that enables me to see stuff !...Well done to the bloke/blokett who came up with the idea of light which I believe was invented in 1932 !....Gosh...light is like...well old !


Here, take a look at this multi-coloured light ! Oooh...what will they think of next ?



Multi-coloured light earlier today.



Nice eh ?..being delivered next Tuesday as the new paint job on my car !


As I have explained above...light is like well old and I believe it moves really fast...even faster than a car or a boat !

With all itís moving about and lasting for ages...does light itself wear out ?......If I shine a laser into deep space will the light just go in a straight line forever (unless it hits something eh?)....Does light fade away and evaporate like a puddle ?


whajafink ?


If it does not age will ewe tell me why it does not ?

ta

hugs and shmishes


mwah mwah mwah


neil
In a darkened room that was not bright
I flicked the switch and saw the light !

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imatfaal

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Does Light Age & Fade Away ?
« Reply #1 on: 19/08/2011 18:09:43 »
It stretches and gets longer wavelength (redder and colder) but if it doesn't hit anything it just keeps on rollin

neilep

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Does Light Age & Fade Away ?
« Reply #2 on: 19/08/2011 18:12:42 »
It stretches and gets longer wavelength (redder and colder) but if it doesn't hit anything it just keeps on rollin

Thanks chum...so it doesn't age and turn into mutton like I do ?....nice !....Well, I sheepose it DOES age surely ?..... but just does not degrade in any way shape or form !....which is also nice !

imatfaal

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Does Light Age & Fade Away ?
« Reply #3 on: 22/08/2011 09:06:19 »
The passage of time for a photon is complex and not understood (despite what many people in new theories will tell you. - not here please guys).  At present it is not known if a photon is affected solely by the passage of time - all changes to photons are within interactions with other factors - the expanding universe causes them to spread out a d get cold, gravity can stretch or compress them (in a complicated process that leads to either getting redder/cooler as they move out of a gravitational potential and blue/hotter as they into one), they scatter off things and lose energy, and they get absorbed by people sun bathing (like me as I type this) - and many other things beside.

Personally , I don't think they age (affected purely by time) in the way that practically everything else does

JP

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Does Light Age & Fade Away ?
« Reply #4 on: 22/08/2011 17:18:49 »
Also, there's a property called diffraction which requires that all physically available laser beams will spread out as they move.  Very high quality lasers might stay as a narrow beam for quite a distance, but they will always spread out.  Over light years of travel, what was a small, bright spot of light on the earth will be an immensely wide and dim beam.

I should add that this property is completely separate from any other effects caused by the expansion of the universe.  Diffraction would happen even if the universe weren't expanding.
« Last Edit: 23/08/2011 02:23:36 by JP »

neilep

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« Reply #5 on: 23/08/2011 19:28:33 »
The passage of time for a photon is complex and not understood (despite what many people in new theories will tell you. - not here please guys).  At present it is not known if a photon is affected solely by the passage of time - all changes to photons are within interactions with other factors - the expanding universe causes them to spread out a d get cold, gravity can stretch or compress them (in a complicated process that leads to either getting redder/cooler as they move out of a gravitational potential and blue/hotter as they into one), they scatter off things and lose energy, and they get absorbed by people sun bathing (like me as I type this) - and many other things beside.

Personally , I don't think they age (affected purely by time) in the way that practically everything else does

Thank ewe very much imatfaal for your very interesting reply. How comforting it is to know that whilst ewe bathe in light, ewe also engage in casual conversation regarding it.

Okay...so...light is flexible !...it stretches and compresses. Can this then give us a warped view of a thing ?...How do we know how to un-warp it to the correct focus ?...and.....as ewe absorb the light ...where does it go ?....thanks for this.

neilep

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« Reply #6 on: 23/08/2011 19:35:21 »
Also, there's a property called diffraction which requires that all physically available laser beams will spread out as they move.  Very high quality lasers might stay as a narrow beam for quite a distance, but they will always spread out.  Over light years of travel, what was a small, bright spot of light on the earth will be an immensely wide and dim beam.

I should add that this property is completely separate from any other effects caused by the expansion of the universe.  Diffraction would happen even if the universe weren't expanding.

Woo!..Thanks also JP !!....why diffract ?...why is it a requirement ?

Robro

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Does Light Age & Fade Away ?
« Reply #7 on: 23/08/2011 21:53:22 »
I do not think that light AGES, or FADES AWAY, I think it changes frequency/wavelength and that energy from light is absorbed by interactions with particles and matter. That said, I do think that light is Red Shifted by means other than Universal Expansion. For this reason...

The Big Bang is busted, it doesn't work, it never has, it never will.


JP

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Does Light Age & Fade Away ?
« Reply #8 on: 25/08/2011 22:05:39 »
Also, there's a property called diffraction which requires that all physically available laser beams will spread out as they move.  Very high quality lasers might stay as a narrow beam for quite a distance, but they will always spread out.  Over light years of travel, what was a small, bright spot of light on the earth will be an immensely wide and dim beam.

I should add that this property is completely separate from any other effects caused by the expansion of the universe.  Diffraction would happen even if the universe weren't expanding.

Woo!..Thanks also JP !!....why diffract ?...why is it a requirement ?

Diffraction is kind of a catch-all term for the way light behaves like a wave as it moves.  It spreads out because waves tend to spread out.  As a simple case of this, think of waves on a pond.  In the extreme case when you throw a stone in, the waves spread out in all directions from the stone.  But if you look at anything moving through the water, waves will spread out from the moving object.

Light is similar.  We can play all sorts of tricks to get these waves not to spread out, but in the end waves like to spread out.  Even if we focus light down to a very small point, it will start spreading out as it moves away from that point.

imatfaal

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Does Light Age & Fade Away ?
« Reply #9 on: 26/08/2011 13:04:17 »
I do not think that light AGES, or FADES AWAY, I think it changes frequency/wavelength and that energy from light is absorbed by interactions with particles and matter. That said, I do think that light is Red Shifted by means other than Universal Expansion. For this reason...

The Big Bang is busted, it doesn't work, it never has, it never will.
Rob

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as you have probably gathered from moderator comments to other posters we like to keep the main science forums for questions and answers in line with mainstream and agreed scientific knowledge.  It is great that you are contributing and please continue - but if you have a theory based on a non-big bang cosmology please give us a rundown in the New Theories section.  Thanks


On the Big Bang - remember that the Big bang theorists were being mocked not that long ago and told that if their theory was true the universe should be filled with the radiation afterglow and it wasn't.  Then we found the CMBR.  It's not proof positive - cos that doesn't exist in science - but it is a really good sign.



 

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