Breakthrough Starshot... or Not?

[Macavity]

Encouraged that people are at least THINKING about:

http://www.space.com/32592-breakthrough-starshot-interstellar-laser-sail-challenges.html

But will it ever work? I suppose the idea of pumping
Gigawatts of Laser energy into nano-satellites was my
initial circumspection! But maybe, if a HIGH enough 
reflectivity could be achieved in the "sail" material?
Otherwise, fried nano satellites are on the menu! 

Other issues too? But Intriguing, nevertheless...

[Joe12345]

I've heard that idea before - but I thought light was massless and therefore contained no kinetic energy? Surely there's a more efficient way than this anyway?

[Macavity]

I sense that electromagnetism is the future of
"acceleration" - Particles, even macrosopic etc.

Another thing that's "obvious"... in retrospect?
https://en.wikipedia.org/wiki/Radiation_pressure

Anyone else remember these things:

https://en.wikipedia.org/wiki/Crookes_radiometer
No harm in being wrong, first time around!
 

[SilverAstro]

On 12/07/2016 at 21:37, Joe12345 said:

but I thought light was massless

It is without rest mass, that is not the same as saying it is without energy or momentum, both of which light does possess.

[SilverAstro]

On 13/07/2016 at 10:17, Macavity said:

Anyone else remember these things: /

No harm in being wrong, first time around!
 

Ok I'll bite

1 ) remember them ! Ha! I can even remember the arguments    Actually that is of no consequence, Maxwell had long since corrected his faux pas before he had need of my assistance  hohohooo

2 ) remember them ! Ha! You can still buy them on th'bay complete with dodgy dossiers, mind you, I'm not sure I'd trust them unto the post.

But they are pretty ! and in an age when we were still batting Steady State vs Big Bang against each other they were a salutary reminder that even eminent physicists are not to be trusted always right