How exciting! (and a thought)

[nikokapo]

if you want an example of some simple mirrors for different wavelengths, look up 'hot' and 'cold' mirrors at edmunds optics. the hot mirrors reflect IR and the cold mirrors reflect visible.

Nice, i always wondered what the difference was! I thought they only differed on the colour (a more silvery one vs. an opaque silver colour).

see? this is why i wanted this section to be created !

 

[likewhat]

EM radiation goes up to very high frequencies. I recently read that in terms of astrophysics they have 10^17 eV photons. That means that the wavelength is 10^-14 nm, which is crazy.

So photon is a unit of quantization of EM radiation, all EM waves are quantized in energy units of photons. Just like acoustic waves are quantized in energy units of Phonons.

When you get to short wavelengths like below maybe 50 nm, lasers use grazing incidence optics. The reflectivity (of materials such as gold) is a function of the angle that the light hits the mirror at. So at these short wavelengths the light will hit the mirrors at maybe 98 degrees from normal in order to not pass through the material. there are regular mirrors around 13.5 nm however, and I believe also around 7 nm, it just depends on the material properties.

Diffraction gratings can also be used for optics when you get to short wavelengths. Also fresnel zone plates are used for focusing very short wavelength light (like 2nm).

When you get to harder Xrays you can start using crystals for bragg diffraction. but at some point the light just goes through everything when you get to gamma rays and there is not much you can do with it.

 

[nikokapo]

EM radiation goes up to very high frequencies. I recently read that in terms of astrophysics they have 10^17 eV photons. That means that the wavelength is 10^-14 nm, which is crazy.

So photon is a unit of quantization of EM radiation, all EM waves are quantized in energy units of photons. Just like acoustic waves are quantized in energy units of Phonons.

When you get to short wavelengths like below maybe 50 nm, lasers use grazing incidence optics. The reflectivity (of materials such as gold) is a function of the angle that the light hits the mirror at. So at these short wavelengths the light will hit the mirrors at maybe 98 degrees from normal  in order to not pass through the material. there are regular mirrors around 13.5 nm however, and I believe also around 7 nm, it just depends on the material properties.

Diffraction gratings can also be used for optics when you get to short wavelengths. Also fresnel zone plates are used for focusing very short wavelength light (like 2nm).

When you get to harder Xrays you can start using crystals for bragg diffraction. but at some point the light just goes through everything when you get to gamma rays and there is not much you can do with it.

Would there be any way to use a very VERY high frequency for communications? It'd go thru everything, but we'd have to find a device that could catch them...

 

[Switch]

And would cause radiation poisoning and cell death because of the short wavelength.Which is bad.

But who knows....maybe shorter than Gamma? Maybe it wouldn't interfere with the wellbeing of organisms in any way....

 

[Hemlock_Mike]

" Vibrations reach on up to become light -- Then through gamma -- outta sight " Moody Blues....

Mike

 

[roSSco]

" Vibrations reach on up to become light -- Then through gamma -- outta sight " Moody Blues....

Mike

 

[nikokapo]

And would cause radiation poisoning and cell death because of the short wavelength.Which is bad.

But who knows....maybe shorter than Gamma? Maybe it wouldn't interfere with the wellbeing of organisms in any way....

Always you with your cancer!

You can get cancer from EVERYTHING, even if you get HIT you could get cancer!!


but i guess you're right....until we find a cure for cancer we wont be having better and faster communications

 

[diachi]

What would happen if you got an extremely high frequency sound though, could it possibly turn into light :-? if it was say 300MHz ? ( or even higher ? )

 

[pseudonomen137]

What would happen if you got an extremely high frequency sound though, could it possibly turn into light  :-? if it was say 300MHz ? ( or even higher ? )

Nope, completely different things. They both propagate with waves, but that's about the end to their similarities.

 

[Switch]

[quote author=Diachi link=1212360910/12#23 date=1212873754]What would happen if you got an extremely high frequency sound though, could it possibly turn into light  :-? if it was say 300MHz ? ( or even higher ? )

Nope, completely different things. They both propagate with waves, but that's about the end to their similarities.[/quote]

Yeah, you know, you can have 300MHz radio waves and it wouldn't be sound.Energy waves != air vibrations. :

Btw, I did not say anything about cancer now.Isn't Gamma too short to cause mutations anyway? :-/
Btw(2) , there is a cure for cancer, we're just not using it.Cancer is our own nature's way of self destructing if we have bad genes.It's natures way of "naturally selecting" those with bad genes from procreating , to make room for the succesful organisms.

Neh , not really, I'm just saying.The governments would probably love milions of people with cancer to sell expensive cancer cures to.

 

[nikokapo]

!=

Hahahaha, C programmer, anybody?

Btw(2) , there is a cure for cancer, we're just not using it.Cancer is our own nature's way of self destructing if we have bad genes.It's natures way of "naturally selecting" those with bad genes from procreating , to make room for the succesful organisms.

Neh , not really, I'm just saying.The governments would probably love milions of people with cancer to sell expensive cancer cures to.

This reminds me of:

"The problem with America is stupidity. I'm not saying there should be a capital punishment for stupidity, but why don't we just take the safety labels off of everything and let the problem solve itself?"

 

[Switch]

I figured everybody knows C , so if I have no "not equal to" symbol on my keyboard, mind aswell.... :

 

[climbak]

haha, i didn't even associate that with C. I just understood it right away. I've been coding way too much lately...

 

[Switch]

haha, i didn't even associate that with C. I just understood it right away. I've been coding way too much lately...

C, C++ , Javascript, PHP , Java too(I think) , all use the != symbol and pretty much the same syntax.You don't have to associate it with C necesarily.