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RussianRocket
03-28-2003, 09:53 PM
I'm not sure when i heard abou this. I was trying to look this up on the net but couldn't find any good links. I've heard that some molecules can act by themselves without any external "push". Anybody that can clear this up woult be greatly apreciated.

Saint Patrick
03-28-2003, 10:37 PM
:lurk:

Reinier
03-28-2003, 11:47 PM
act by themselves? could you be a bit more specific?

PowerManDL
03-29-2003, 12:08 AM
What he said.....I need you to narrow that down a bit before I can begin to comment.

RussianRocket
03-29-2003, 12:51 AM
forming together, acting without reason. Something along those lines

Reinier
03-29-2003, 12:57 AM
doesn`t make sense.

GonePostal
03-29-2003, 01:06 AM
Diffusion?

body
03-29-2003, 08:42 AM
everything has a reason, we just do not know what the reason is.

kind of like women.

Praetorian
03-29-2003, 11:51 AM
deep man.

i dont think that molecules can just *act* by themselves without any external factors playing a role. Its not like they go *puff* and some **** happen. You need external factors.

the doc
03-29-2003, 12:07 PM
there is always a thermodynamic or entropic reason to explain the behaviour of molecules

they never just act

kook
03-29-2003, 07:41 PM
Originally posted by the doc
there is always a thermodynamic or entropic reason to explain the behaviour of molecules

they never just act

very true, but if it were true, we would have the "perpetual motion machine" man has been trying to make for many years, but by the laws of physics not possible

Alex.V
03-29-2003, 07:44 PM
Originally posted by kook


very true, but if it were true, we would have the "perpetual motion machine" man has been trying to make for many years, but by the laws of physics not possible

No, because said machine would require external force to coordinate said motion. Which requires energy.

kook
03-29-2003, 08:17 PM
Originally posted by Belial


No, because said machine would require external force to coordinate said motion. Which requires energy.


hmm.. thats what i meant to put across, if there were no external forces making something happen, we have a perpetual motion machine, but its impossible
i'm pretty sure we're on the same page, just some miscommunications
the socalled definition of a perpetual motion machine is one that once started with an external force will never need another external ever again


in this case someone said they heard atoms/molecules could act without an external force

WestyHeadbanger
03-29-2003, 08:20 PM
These molecules are they just gravitating towards each other? If so that is within the known realms of physics.

Podium Kreatin
03-29-2003, 08:55 PM
don't electrons ahve an intrinsic nature of repelling each others? there are a mix of attractions and repulsions between atoms all the time w/o added energy, and kinetic energy as long as T>0Kelvin (even at 0K, some say kinetic energy exists).

WestyHeadbanger, gravitational force is immeasurable til u get to the gigantic masses, such as planets, and even that, earth's gravity is considered very weak. atoms dont' have significant gravity, b/c if they did everything'll be clumped together, which defies entropy

GonePostal
03-29-2003, 09:28 PM
Basic columbs law. There is energy involved. It takes energy to move those 2 charges into proximity. From a reference point say infinity to point a.

Chomsky
03-29-2003, 10:23 PM
Originally posted by Podium Kreatin
don't electrons ahve an intrinsic nature of repelling each others? there are a mix of attractions and repulsions between atoms all the time w/o added energy, and kinetic energy as long as T>0Kelvin (even at 0K, some say kinetic energy exists).

WestyHeadbanger, gravitational force is immeasurable til u get to the gigantic masses, such as planets, and even that, earth's gravity is considered very weak. atoms dont' have significant gravity, b/c if they did everything'll be clumped together, which defies entropy
Electrons don't repel each other intrinsically.
What you are thinking of is how they act in an ionic compound, called electronegativity. Electronegativity determines how the atoms are shared inside said compound... For example, francium and flourine react to make francium flouride (FrF). Francium has an electronegativity of 0.7, and fluorine is 4.0. The atoms are unequally shared. Fluorine gets all the electrons and francium gets none!
That's the only occasion I can think of where electrons are attracted differently, because they are all negative charged!

Chomsky
03-29-2003, 10:27 PM
As for the topic of this thread, I am not a physicist, but I can shed some light.
No.
Not possible, according to our current view of how the world works. It would violate the laws of thermodynamics. You can't have an action without a catalyst.

GonePostal
03-30-2003, 12:28 AM
Chompsky there are things called point charges. Opposite charges attract like charges repel. This is the basics of any Electricity and Magnitism course. You have it confused with ionic compounds which are derivatives of E & M. Electrons in essence are point charges since their mass is so small.

1st law (or 2nd or 3rd can't remember) says you can't destroy or create energy. What was proposed tries to break this rule. As far as I know there is nothing that breaks this law.

Chomsky
03-30-2003, 12:32 AM
oh, of course. i'm ****ing stupid. i took that stuff last year.
He says that a molecule that moves itself without any outside force acting on it exists.
That's creating energy, not changing it from different forms.

GonePostal
03-30-2003, 12:43 AM
:) hehe too much chem for you!

WestyHeadbanger
03-30-2003, 09:58 PM
Originally posted by Podium Kreatin

WestyHeadbanger, gravitational force is immeasurable til u get to the gigantic masses, such as planets, and even that, earth's gravity is considered very weak. atoms dont' have significant gravity, b/c if they did everything'll be clumped together, which defies entropy

Excuse me.

I think this is what you are after RussianRocket, PodiumKreatin be careful with making absolute statements, they have a 99.9% probability to be proven incorrect in the near or distant future:

[73.20] Density Interface Instabilities in Molecular Clouds; Self-Gravity Driven vs Rayleigh-Taylor
R.M. Hueckstaedt (Los Alamos National Laboratory, Applied Physics Division)

The structure and evolution of molecular clouds are affected by a large number of physical processes, including self gravity . In recent years, studies have shown that an interface of discontinuous density is unstable to perturbations due to the action of self gravity . Crenulations along the interface grow as the system seeks a lower energy state. Theory predicts a growth rate of the order of the free-fall time in the denser medium, even when the perturbation wavelength is less than the Jeans length. In the incompressible limit, the growth rate is independent from the perturbation wavelength. An ongoing computational study of the self-gravity driven interfacial instability (SGI) seeks to validate the linear theory and examine the nonlinear behavior. Preliminary results have shown growth rates in agreement with theory. Here, I present the latest results from hydrodynamic simulations using an expanded parameter space to further explore the behavior of the SGI. Comparison is made with the well studied Rayleigh-Taylor instability.

PowerManDL
03-30-2003, 10:03 PM
Ah, that.

I figured that's where this was heading.......chaos theory is a bit beyond my scope to elaborate on at this point, though.....

Suffice it to say, given enough randomness you eventually find order.

WestyHeadbanger
03-30-2003, 11:47 PM
:D

Podium Kreatin
03-31-2003, 07:46 AM
Originally posted by Chomsky

Electrons don't repel each other intrinsically.


electrons do have repulsion w/o extra energy (maybe intrinsic was teh wrong word). that's where normal force comes from (when you are standing on the ground, your atoms never touch the 'floor' atoms, the electron repulsion pushes u up so u don't fall straight down to the bottom of the earth.)


Originally posted by Chomsky

He says that a molecule that moves itself without any outside force acting on it exists.
That's creating energy, not changing it from different forms.

this does happen. even absolute zero (T=0K) some elements are still in liquid or gas phase, so therefore, there has to be movement even w/o energy (b/c fluid/solid phase is based on movement of atoms at certain conditions). soem say that there's no such thing as absolute zero. in both cases, they both say there is always gonna be some energy that always exist

gino
03-31-2003, 08:34 AM
Isn't the answer to this question dependant on which matter we're discussing - atoms OR molecules? Each acts differently as far as I can remember from my remedial college chem classes.

PowerManDL
03-31-2003, 10:53 AM
Originally posted by Podium Kreatin
this does happen. even absolute zero (T=0K) some elements are still in liquid or gas phase, so therefore, there has to be movement even w/o energy (b/c fluid/solid phase is based on movement of atoms at certain conditions). soem say that there's no such thing as absolute zero. in both cases, they both say there is always gonna be some energy that always exist

Absolute zero can't exist......there's always going to be some energy content, no matter how small.

For a molecule, that'd be true. However, for a single electron....quantum mechanical issues begin to take over and you can indeed get "energy from nothing." Which is why, fundamentally, you can never reach true Absolute Zero.

WillKuenzel
03-31-2003, 11:00 AM
I thought absolute zero was where the atoms quit moving, not necessarily the protons and electrons but the molecule. Is that what you are saying?

And haven't they reached even a little less than absolute zero in some labs?

PowerManDL
03-31-2003, 11:11 AM
Well.....that's getting tricky.

At that level, temperature is defined by the motion of the atom. To reach true absolute zero would require that the electrons themselves be reduced to the lowest possible energy state.

This, for many reasons I don't care to explain right now, can't happen.

So no, nobody's been able to reach zero energy content.

WillKuenzel
03-31-2003, 11:25 AM
I've sort of gotten a handle on some of the aspects from a few chemistry and engineering classes. I just wanted to make sure I was on the same path.

As far as zeo energy state, I'd have a hard time ever believing that is possible but it could happen at some point I guess. As far as temperature and the theoritical 0 degrees Kelvin or something, hasn't that been achieved?

eh, nevermind....http://www.wikipedia.org/wiki/Absolute_zero
I thought they had gotten close to it.

PowerManDL
03-31-2003, 11:28 AM
Exactly.

I'm always right.

Tiare
03-31-2003, 11:39 AM
Interesting conversation.

To answer the original question, it is an impossibility to have molecules without some form of push (assuming that by push you mean energy source) because molecules are the strong magnetic force that holds multiple atoms together. If you did not have that force (strong magnetic push) then the molecules (and indeed the atoms themselves) would fall apart and no longer exist. I think that they are currently exploring this and finding a substance that they call plasma in near 0k environments. I don't know if plasma itself has energy or just energy potential.

To have an atom or molecule, there must be force exerted. Or so I have been taught.

PowerManDL
03-31-2003, 11:50 AM
Originally posted by Tiare
To answer the original question, it is an impossibility to have molecules without some form of push (assuming that by push you mean energy source) because molecules are the strong magnetic force that holds multiple atoms together.

Its actually electrostatic.

If you did not have that force (strong magnetic push) then the molecules (and indeed the atoms themselves) would fall apart and no longer exist. I think that they are currently exploring this and finding a substance that they call plasma in near 0k environments. I don't know if plasma itself has energy or just energy potential.

mmmm I couldn't see a plasma existing in a low-energy environment.....cold plasma is almost an oxymoron. You might be thinking of superfluids.

As the earlier studied alluded to, there can be some degree of self-organization occuring in a dynamic fluid system; but that's based on the random interactions of the molecules achieving a non-random configuration.

Tiare
03-31-2003, 12:03 PM
Thanks for the clarification, Powerman.

Strong magnetic force is only exerted on the nucleus of the atom, while electromagnetic force causes the electrons to maintain orbit, do I have that right?

Regardless, the molecule and the atom can not exist without that energy source acting on it's components, right?

body
03-31-2003, 01:01 PM
Originally posted by PowerManDL
Well.....that's getting tricky.

At that level, temperature is defined by the motion of the atom. To reach true absolute zero would require that the electrons themselves be reduced to the lowest possible energy state.

This, for many reasons I don't care to explain right now, can't happen.

So no, nobody's been able to reach zero energy content.

if it were possible, you would not be able to prove it, by measuring it, you would create movement, therefore raising the tempeture.

the uncertainity prinicple coming into effect again.

Praetorian
03-31-2003, 01:14 PM
holy christ!! i didnt know that PLs and BBs could have such a conversation. im mighty impressed.

very good read for me since im gonna have a test in this next week.

:p

PowerManDL
03-31-2003, 02:01 PM
Originally posted by Tiare
Strong magnetic force is only exerted on the nucleus of the atom, while electromagnetic force causes the electrons to maintain orbit, do I have that right?

That's actually the strong nuclear interaction that keeps the nucleus bound-- and yes, electromagnetic forces do keep the electrons in their orbits.

Regardless, the molecule and the atom can not exist without that energy source acting on it's components, right?

That is true, but its not something that should be seen as an energy "source".....this is dealing with the fundamental force-carrying units of the respective energies. That'd be like saying you're trying to get a raindrop wet.

An atom is a self-contained, and so far as we've seen, fundamentally stable system.

body-- that's dead on.

Gyno Rhino
03-31-2003, 02:13 PM
I knew this would end up in chaos theory.

Bottom line is we don't know for sure. And we probably never will.

SO, sip a protein shake and scratch your ass. It HAS been proven that thinking will make you smarter. And that is something we ALL want to avoid.