Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

[Radio Controlled]

Re: Rez and Radio Controlled.  That article has no references, no peer review, and without them, no validity.  Do not attempt to use a 'freelance writer' as a source in a discussion regarding hard fact, so I'm going to NASA.  Point 1:  Diffraction is by no means a property of radiation, it is a property of medium and the reflector, improving either the 'purity' of the medium or the 'perfection' of the reflector will decrease loss.  Point 2:  Right now small aperture lasers can maintain tight coherency over a range of some millions of miles.  I just verified these points with this helpful article http://ntrs.nasa.gov/search.jsp?R=19880014441

...The hell are you even on about? I just linked that article because it was relevant and interesting.

I'm not sure what you're trying to prove here, but I'm not playing along.

[Rez]

We've made up diffraction. 

ed: Honestly, if you're going to cite a 500 page 'article' (in reality, someone's Masters thesis) to support two claims, you better be giving me page numbers.  As it is, it just looks like you're trying to waste my time and appeal to authority.

[Radio Controlled]

We've made up diffraction.

Cool, I've never got to invent a physics law before.

Wanna call it the Rez-Controlled principle?

[NullForceOmega]

A master's thesis IS a peer reviewed scientific article, and if you can't be bothered to read even the gods be damned table of contents then I can't be bothered to deal with you.

[Rez]

Thanks for that.

[origamiscienceguy]

I like reading atomic rockets' articles about space and futuristic space warfare. I also think that their page about common misconceptions is really funny.

[mainiac]

That site annoys me, the dude running it seems to think that the ability to spot the lazier mistakes in science fiction confers the ability to know all right and wrong.  It's like a giant forum argument against a strawman.  And the sheer lack of imagination makes me wonder what kind of perverse impulses drives the man to study science fiction.

I mean reactionless drives are supposed to be impossible without completely screwing physics?  Okay, well what happens when you  take mirror flywheels across your center of mass, spin them one way at one part of the orbit and spin them back at another part?  Well shucks, you've just changed your orbital trajectory without a quark of propellant.  I'll grant you it's hardly a powerful method given the technology we have today but it's clearly not something that's impossible.  Some know it all nerds from a civilization that's only every built spacecraft around launches from earth can't tell us what engineers with completely different priorities are going to work out.

[Arx]

I'm not a great fan either, largely because they seem to be in the camp of "if it's not possible with current technology, it's not possible ever and you are a bad person for using it in your story."

It's an attitude which irritates me a little, although they dilute it by allowing for the use of handwavium. It comes off that way, though.

[PTTG??]

That site annoys me, the dude running it seems to think that the ability to spot the lazier mistakes in science fiction confers the ability to know all right and wrong.  It's like a giant forum argument against a strawman.  And the sheer lack of imagination makes me wonder what kind of perverse impulses drives the man to study science fiction.

I mean reactionless drives are supposed to be impossible without completely screwing physics?  Okay, well what happens when you  take mirror flywheels across your center of mass, spin them one way at one part of the orbit and spin them back at another part?  Well shucks, you've just changed your orbital trajectory without a quark of propellant.  I'll grant you it's hardly a powerful method given the technology we have today but it's clearly not something that's impossible.  Some know it all nerds from a civilization that's only every built spacecraft around launches from earth can't tell us what engineers with completely different priorities are going to work out.

Uh, I'm not sure I get what you're saying about the flywheels. Are you saying you found a way to turn rotational inertia into linear inertia?

[mainiac]

That's trivial, no?  The problem is that it's a vastly inefficient from an engineering standpoint.

[Il Palazzo]

Okay, well what happens when you  take mirror flywheels across your center of mass, spin them one way at one part of the orbit and spin them back at another part?

Can you restate the set-up? I don't see what you're trying to do with it. Where are the flywheels? Can you draw it in paint maybe?

I have to warn you, I see this as an a-priori faulty concept due to conservation of momentum issues, but I'm willing to try and spot the specific mistake in the design.


I do agree on the general sentiment for that site, though.

[i2amroy]

Yeah, that site may be crazy, but if they are saying reactionless drives are impossible they are kinda right. The only reaction less drives you can really do in current physics are things like the Alcubierre drive, and take crazy things like negative mass to pull off correctly.

[mainiac]

Hm, I was thinking about conservation of energy and momentum within the orbital profile but not within the vehicle itself.  So a flywheel setup wouldn't do it simply.  Still, there are different orbits with the same energy and momentum so I would be slow to conclude that a reactionless drive isn't possible.

[Il Palazzo]

but not within the vehicle itself

That's the most important part, though. No matter what you do within the closed system of the vehicle, its centre of mass will keep on its trajectory as if nothing happened. To propose a different outcome goes against as fundamental physics as Newton's 1st law of motion.

[mainiac]

I know the laws when I'm designing spacecraft at 2 A.M.