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[Yanlin]

Yanlin: If you can make it, they can use it. It's not too difficult. There's no limit on human energy use, just a limit on imagination or the ability to think beyond one's current usage.

You'd be amazed how insanely difficult it is to use that much energy even if you design a product to just waste energy.

[Neonivek]

Topics like this clearly show that I don't pay enough attention to the General Discussion board. I'm really interested in Nuclear stuff, but it's too bad I'm too dimwitted in the subject to discuss it.

Goodness remember when people honestly believed radiation could do just about anything? (Ignoring light as radiation)

One second as I drink another radioactive health drink. 

It is a shame that all it can do now is cure cancer, provide X-rays, and provide a low poluting source of power.

What drives me insane is that I heard about Fusion a long time ago (back when it was Nitrogen being used) and I don't see any end in sight.

[Areyar]

to continue my previous post about photonic speed inside a pressurised plasma:

Somehow plasma nuclei must be able to absorb massive amounts of energy and emit it at wavelengths typical for the exitationstates for the atom, otherwise stellar spectroscopy would not be able to extrapolate the composition of a star.

This have been bothering me and I now realise my error here:
spectra are absorbtion spectra, not emission.
Solar radiation is the broad smear of heatradiation, except at the wavelengths for atoms that make up a star, at these discrete wavelengths light
is absorbed.

ps my browser is being anoying: I cannot read the line that I am typing onscreen;
It keeps jumping up to the end-quote tag. grr.

[Il Palazzo]

Yeah, but to gain this uniformal, continuous spectrum from rather discrete wavelenght photons, that are produced during stellar fusion, you actually need those colisions in the plasma. I'm guessing here(since my memory is failing me) that photons exchange their momentum with plasma particles, thus changing their wavelenght. Given the large amount of such collisions and their random outcome, you should get the continuous spectrum of light, with absorption lines only from the outer layers.

[Twiggie]

i thought
as p=mv
photons cannot have momentum

[Il Palazzo]

photons are tricky. They've got a momentum associated with their frequency/wavelenght:
p=hf/c(h-planck's constant, f-frequency, c-speed of light in vacuum)

[Virex]

i thought
as p=mv
photons cannot have momentum

p = mv
In the caser of a photon, that becomes
p = mc
m = e/c^2
e = h*f (see special relativity for further explanation)
so for a photon, the momentum is given by:
p = h*f/c, Q.E.D.

[Neonivek]

I guess this is why Nuclear physics isn't part of general advanced physics.

[Dakk]

Topics like this clearly show that I don't pay enough attention to the General Discussion board. I'm really interested in Nuclear stuff, but it's too bad I'm too dimwitted in the subject to discuss it.

Goodness remember when people honestly believed radiation could do just about anything? (Ignoring light as radiation)

One second as I drink another radioactive health drink. 

It is a shame that all it can do now is cure cancer, provide X-rays, and provide a low poluting source of power.

What drives me insane is that I heard about Fusion a long time ago (back when it was Nitrogen being used) and I don't see any end in sight.

Well since the scientists didn't yet know how exactly the atom chain reaction from a nuclear explosion would ever stop, and had reasons to believe such scenario as possible, then yea, it was a well founded fear.
What makes us humans awesome is that someone somewhere will test stuff most woundn't, they just dropped the bomb and hoped the universe didn't explode .

Same thing now with dark matter. While scientist don't think a matter + dark matter reaction could destroy the universe, we don't know exactly how much energy such reaction would release, we just know a small quantity can beat several heavy duty nitrogen bombs. So yea, it can poentially take NY off the map, or the whole world.

[Il Palazzo]

dark matter

surely you mean antimatter?

[Dakk]

I was just trying to stimulate racial diversity

[Neonivek]

it was a well founded fear

I wasn't just speaking about fear. They also believed in its health capabilities a bit too much.

That Radioactive health drink for example actually existed.

[Grek]

We know exactly how much energy a given matter-antimatter reaction will release: 1,497,510,358 kilojoules per milligram of antimatter. No more, no less.

[Leafsnail]

Yes, Dark Matter, a theoretical... substance?  Probably not the right word.  Anyway, it's theoretical, and could potential explain the universe's rapid expansion (something to do with them having negative gravity.  But I'm not an expert).  Different to antimatter, discovered decades ago and now widely used in MRI scanners.

[Neonivek]

Well I thought Dark Matter doesn't technically exist it is really just a catch all term for matter that must exist due to inconsistancies in what we discovered and how we know the universe should function.

It is kinda funny how a lot of Sci-fi make Dark Matter some sort of super substance. It would be like saying your flying a "UFO". If you know what it is I don't think it would be called Dark Matter anymore.