X-ray and Gamma ray mirrors... and Perfect Mirrors

[Spacescifi]

 

What properties would a material that is an x-ray mirror have?

Exotic or unusual properties?

Same question for a gamma ray mirror?

Is a perfect mirror possible with known science? Or impossible?

Meaning that 100% reflection is impossible?

Some heat must be absorbed?

Interestingly...perfect mirrors of any part of the EM spectrum would solve the waste heat problem in space.

 

Even if it was only X-rays perfectly reflected, or gammas. Or IR, or even optical light.

Just surround the engine with the material and radiate all your heat from mirror ports.

It could even provide laser sail thrust minus the sail, since your ship's waste heatbeing reflected off mirrors would be the thrust.

Intense heat could provide greater thrust.

Imagine if you lit off a nuke and the X-rays and gamma rays were totally reflected, how much extra thrust would that generate?

 

Side effect: Laser weapons only do damage now if one does not have 100% reflective mirrors that block that ray.

Edited October 31, 2020 by Spacescifi

[Nuke]

nanotech waveguides perhaps? probibly only would work on xrays, gamma rays have too small wavelength to manipulate with physical structures. 

[kerbiloid]

A cloud of superdense particles turning 180° any photon trajectory with their relativistic gravity fields.

[UmbralRaptor]

Generally x-ray mirrors use weird alternating materials, since they only work at shallow angles.

A perfect mirror as you're implying is probably impossible because of conservation of momentum. (ie: photons usually lose energy very slightly when undergoing *elastic* scattering)

Also, I have bad news for you about photon drive thrust.

[Pds314]

Waveguides and grazing incidence mirrors are pretty typical for everything harder than UV-B. I don't know of anything that can just straight up reflect an X-ray at 180 degrees with any reasonable efficiency.

 

Re: perfect mirrors solving waste heat. I don't think so. For one, given specific angles, 99.99% for visible and near IR is achievable with modern tech. As Q switched lasers often use. My question is then why are you trying to reflect blackbody temperature equivalency of like 10000 K +? Also your engine needs to be able to survive emitting at that temperature which isn't easy. And that engine is probably not aneutronic. Reflecting neutrons efficiently is not nearly as simple as reflecting photons efficiently.

 

I have heard the idea proposed that microwaves in a plasma faraday cage under certain conditions (believed to be present in ball lightning by the study authors) would have something like within 10^-11 of perfect efficiency in a microwave cavity, allowing the microwaves to bounce around inside like some crazy photon gas for extended periods of time. But again that's only microwaves.

As for nuclear pulse, one, there's a pretty good amount of force there. With very efficient ablative mirrors you can indeed get about an equal mass loss of the weight of the nuke in the pusher plate/sail but you need it to survive a close range nuclear detonation and all the forces that imparts.

Edited November 6, 2020 by Pds314

[vv3k70r]

On 10/31/2020 at 6:17 PM, Spacescifi said:

Meaning that 100% reflection is impossible?

Difraction and nonelastic scatering prevent any material (because of wavelength determine the atomic positions) in terms of atoms (build of core and electrons) from such use (atoms are simply to big for such a 100% lens/mirror). But there are other materials that are slighty "smaller" (like positronium) or "denser" (hyperatoms) that could propably lead to a slightly better results (but we have obvious issues with them) but not in near future.

In simplest way - such a mirror need to have higher "temperature" (temperature in such an object is energy aprox taken from motion, not something measurable directly) than the beam itself so it can transfer its energy back.

But for the aplication You like the big sphere (of aluminium, berilium, lithium, tungsten acording to specyfication) around the source would do the job if the sphere size give its energy disipation higher than gain from source. It means big, heavy sphere reducing TWR.

[lajoswinkler]

Grill made out of golden mirrors is what's used for shallow angle diverting x-rays.