Gravity?

[Dauphin]

Originally posted by Chowlett
SD - who does that refer to?

Juggernaut.

A result of having several windows open means I missed your post.

[Ecthy]

he just thought higher potential energy means more force, what balls

[Adalbertus]

A force itself doesn't need any fuel. If you tighten a rope between two rods, the rope exerts a constant force without any refuelling. Fuel is energy, not force. When you move something against a force, you spend energy.
This is partly why physicists rarely think in terms of a force. Energy seems to be more abstract at first but its a much easier concept. Force is not wrong, but simply more complicated. Also mathematically.
Gravity cannot "run out of energy". The gravitational field exists. You expend or gain energy if you move something in a gravitational field. When the moon comes a bit closer to earth it gains energy from the gravitational field and becomes faster, i. e. its kinetic energy increases. When it moves away from earth it becomes slower. The sum of the kinetic energy and the energy gained from/given to gravitation remains constant. (in this simple picture, that is).

[Lancer]

"It's Lancer thread week again"-Ecthelion

You must admit Ecthelion, it's been a while.

Thanks for are the replies, I'm still trying to figure it all out.

[Dauphin]

Not soooo wrong.

he just thought higher potential energy means more force, what balls

A greater rate in change of potential (with respect to distance) would.

[blackice]

Originally posted by chegitz guevara
Gravity sucks!

The Earth has no gravity it sucks

[Lancer]

What is a 'graviton'? A fanciful invention of the writers of Star Trek? Anyone?

[Ramo]

How do you figure that one out, or are you refering to Gaussian shapes?

Yep, Gauss' law works.

Flux(F/m) = [rho]/some constant (whatever the gravitational analogue to the permitivity constant is)
F = GMmr/||r||^3
And M = [rho]4[pi]||r||^3/3

So F = 4/3*G[rho][pi]mr

[Ecthy]

*head explodes after only looking at Ramo's post*

Originally posted by Lancer
What is a 'graviton'? A fanciful invention of the writers of Star Trek? Anyone?

it's a gravity quantum

[Ramo]

The graviton is the supposed (we don't know if it exists, hell we don't know if gravity can be renormalizable QFT) force carrier for gravity.

[Provost Harrison]

Oh don't turn this all mathematical. It isn't pleasant, it doesn't help Lancer one jot and just scares people away.

Stop it now you naughty children

[Adalbertus]

A graviton is a concept among those physicists who try to unify the General Relativity with Quantum Theory (which still are not entirely compatible). For SMAC fans: It's "Unified Field Theory".
The basic idea is that if for the electromagnetic field there is the photon as exchange particle, i. e. which communicates the interaction between electromagnetically charged particles, the Weak Interaction has W- and Z- Bosons and the Strong Interaction, which binds quarks in the nucleus of an atom, has the gluons, there should be a similar particle for gravity. There are no experimental proofs for their existence, but some experiments are planned which *might* find them ...
So, at the moment I would regard gravitons as a well-founded speculation.
Not invented by Star Trek

[Lancer]

Geeez guys...

A simple 'we don't know' would have sufficed.

[our_man]

Gravity...

I've always wondered - does Archimedes Principle still hold true in space? If so, couldn't the bouyant force it generates offset the effects which the absence of gravity causes in astronauts?

This is all theoretical of course, because unless it filled completely a sealed container it would float around the place. But still, could any of the physicists out there tell me how this law behaves in the absence of gravity?

[Ecthy]