light moving solids

[sheldoncooper]

hi

 

maybe i won't get a full explanation to the possibility to my idea but still i would like to hear some thoughts on my idea on moving a spaceship at the near speed of light (or possibly at the same speed or beyond, idk, this is theoretical thinking)

 

if light could repel material we could build a spacecraft made of this material and expose it to light making it accelerate to at least the speed of light. so yeah that there is my idea.

 

two things come to mind that would create chaos in this construct. 1- the violent instant acceleration of the spaceship when exposed to light; 2 - the disintegration of the spaceship going at the speed of light, if it resists the instant acceleration.

 

maybe we can control the amount of "repel" the spaceship has toward light and create a secure acceleration.

 

but in general, what do you think of this?

 

and if you could point me to some online wikis on why this would not be possible or possible that would be great.

 

 

thanks

Edited October 9, 2010 by sheldoncooper

[insane_alien]

well, there is such a thing as radiation pressure but it will neither cause violent accelerate nor get you to the speed of light.

 

it is impossible to get to the speed of light due to relativistic mechanics.

 

you should go look up 'solar sails' the current favourite light based propulsion technology.

[sheldoncooper]

ya

thanks for that

im disappointed at the current favorite light based propulsion system

it seems neanderthalic

but looking at history and sail boats there might be a pattern there and hope for the future in light propulsion.

 

cheers!

[TonyMcC]

If you want to see something moving in response to light look up "Crookes radiometer". Google will do the trick. The amount of force, however, is very small.

[swansont]

The standard Crookes radiometer you can buy on the cheap (it's not in a vacuum) works on heating rather than radiation pressure — the vanes move the opposite way for the two effects.

[TonyMcC]

I understood that in the Crookes radiometer if the vanes are in a vacuum then photons bouncing off the silver side produce a very small force. However if the vacuum is partial then thermal transpiration is the main motive force (and in the opposite direction). I read that if the vanes are in a vacuum the amount of force due to photons, although real, is so small that the vanes would need frictionless bearings if they are to rotate. I have therefore to accept that the Crookes radiometer that you can buy is not really a photon driven machine - sorry!

[sheldoncooper]

the crooks meter appears to be somewhat of a hocus.

never the less, i'm still into having light move stuff at high speed.

i thought about magnetic photons - which to my understanding would be able to create a repel between light and material but i think i've found my answer:

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

well good luck to any scientists out there if they are to discover magnetic photons.

im somewhat disappointed and my theoretical repel spaceship has crash landed.