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Superreflectance hypothesis

Mirror property to reflect 100% of light...
  [vote for,

Suppose you want to store energy in empty space rather than a battery. It's easy to think of compacting lots of photons into space. What you need, is either a black hole, or a superreflector.

All modern materials have non-100% reflectance. For example, silver has 98.2% for 550 nm wavelength.

So, a hypothesis: a material exists with very close to 100% reflectance.

(Similar to superconductivity, and superfluidity.)

If exists, just imagine how light batteries could be....

Inyuki, May 09 2015

98.2% - for silver, from here. http://www.kayelaby...sics/2_5/2_5_9.html
[Inyuki, May 09 2015]

can you permanently capture light? https://m.reddit.co...ntly_capture_light/
[xaviergisz, May 09 2015]

Total Internal Reflection http://www.physicsc...Internal-Reflection
Partway to Maxwell's daemon [csea, May 09 2015]

Wikipedia - Reflectance http://en.wikipedia.org/wiki/Reflectance
[Inyuki, May 10 2015]

Slow light down to 60 km/s http://news.harvard...999/02.18/light.htm
[AusCan531, May 11 2015]

attenuation in optic fibre http://upload.wikim...-Zblan_transmit.jpg
from wikipedia [xaviergisz, May 11 2015]


       Yeah, I agree, these are big questions, [bigsleep]. Light explosions, among the risks.   

       But before even having these questions, the biggest one is -- would such material be possible.
Inyuki, May 09 2015


       A company called Newport makes mirrors with reflectivity >99.7%, but this is a bit like the difference between a good conductor and a superconductor.
MaxwellBuchanan, May 09 2015

       Problem is, even with 99.7% reflectivity we get just 100 bounces till we drop to just 74% left. So, if we have mirrors 3 m apart, that would give 0.000001 second to drop from 100% to 74%. (with mirrors 3000km parat you could see something of macroscopic time though)   

       To sustain for 1 second for mirrors 3 m apart, we'd need reflectivity 99.9999997% to sustain 100000000 bounces till we drop from 100% to 74%.
Inyuki, May 09 2015

       [bigsleep], very interesting! I wonder, what's the transparency/resistence of fiber optic cables.
Inyuki, May 09 2015

       Could a geometry be derived within a series of steps in or graduated indexes to create multiple / infinite TIR [link] ?
csea, May 09 2015

       Hmm, [xaviergisz]' link says no. Oh, well...
csea, May 09 2015

       Maybe, this will be the battery that you have to put a small % of energy into, for a structure and enviroment that can store the light.
wjt, May 09 2015

       If you had a very small black hole, you could just place the light In orbit, not thought of how to get it out though.
bs0u0155, May 10 2015

       The graph that shows reflectance curve in Wikipedia looks asymptotic to y==100 line.   

       Seems like the longer the wavelength the higher the reflectance.   

       I wonder if there's a sweet-spot for some wavelength and material.
Inyuki, May 10 2015

       It seems like you could see back into the past with this.   

       Eventually, I'd think the light would heat up the medium and dissipate.
RayfordSteele, May 10 2015

       [bigs], the Wikipedia article says TIR can get up to 99.999%, which is four nines short of what's needed here and many more short of perfect.   

       If a perfect mirror doesn't exist, you might need achieve the same thing by letting the light go in a straight line and bending space. A couple of very tiny black holes a few mm apart would do the job - just launch the light into a figure-8 orbit that skirts the two event horizons.
MaxwellBuchanan, May 10 2015

       [bigsleep] Does this mean the exotic materials, once flooded internally to saturation with light, would have novel behaviours?
wjt, May 11 2015

       //To sustain for 1 second for mirrors 3 m apart, we'd need reflectivity 99.9999997% to sustain 100000000 bounces till we drop from 100% to 74%//   

       Only when light travels a full 300,000 km/s If you could slow it to down to 60 km/s as per the linked article sustainability increases markedly.
AusCan531, May 11 2015

       //[MB] Read it again carefully. "Perfect mirrors exist as TIR//   

       Ah yes, it seems you are right and I was wrong. Howevertheless, you're then left with the problem that the light is travelling through a dense medium (such as glass or water). I'm not sure how transparent a material can be, but optical fibres generally have boosters every few tens of kilometres. This suggests that light in an optical fibre is attenuated (presumably by absorbance) by a significant factor over that sort of distance.
MaxwellBuchanan, May 11 2015

       //Some cores are better than others.//   

       True, and I agree that surface defects probably account for some of the losses. We need an estimate of the losses due to absorbance by the glass.
MaxwellBuchanan, May 11 2015

       You're assuming that all the losses are reflectance losses. How much light is lost through absorbance?
MaxwellBuchanan, May 11 2015

       //About 50% as I just mentioned. // Wait - I'm meant to be paying attention?
MaxwellBuchanan, May 11 2015

       Don't pay anything! Does TER work? A vacuum fibre...
Ling, May 12 2015

       No - the light will bounce back and forth between the sticky-outy bits of the E and get absorbed.
MaxwellBuchanan, May 13 2015

       Is there a limit for the maximum photon density in a defined volume for the natural world? say inside the sun or a black hole.
wjt, May 14 2015

       Send the idea to Elon, Im sure Solar City would like make their home batteries a bit more flashy and prestigious.   

       P.S everyone please buy more Solar panels. II need to make sure my investments meet their targets this year.
bob, May 15 2015


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