Molecule Breaks Laws of Physics, Beats Friction

[Archaic`]

This story I was linked to comes from FOXNews, so take it with plenty of grains of salt.

http://www.foxnews.com/story/0,2933,189909,00.html

Molecule Breaks Laws of Physics, Beats Friction
Friday, March 31, 2006
By Bjorn Carey

Scientists have found a molecule that can spin freely in liquid, clearing out water as a person swinging suitcases would clear a crowded room.

The molecule spins without causing friction. That shouldn't be possible, according to a chemical physics theory. The finding could alter the way scientists think about chemical reactions in liquids.

Researchers hit a drop of iodine cyanide and water with pulses from an ultraviolet laser, exciting one type of molecule to reconfigure into a small, peanut shape with a carbon atom on one end, a nitrogen atom on the other.

The molecule heated up to 8,000 degrees Fahrenheit (4,427 Celsius) and started spinning at a furious 270 trillion rotations per minute.

Outta my way

Within the first quarter-turn, the molecule created a shock wave that kicked away surrounding water molecules. The peanut molecule created a nearly frictionless zone for itself in the 10-trillionths of a second the reaction lasted.

"If you give it enough spin, it pushes all the guys around it away, and it builds itself a little bubble," said study co-author Stephen Bradforth of the University of Southern California. "It's destroyed the friction in the liquid around it by completely reshaping its environment."

After the molecule completed about 10 rotations, the shock dwindled and the water molecules rushed back in.

Despite its fleeting nature, the reaction managed to smash the linear response theory, a chemistry model that states such a thing can't happen in a liquid environment.

"You can see molecules behave this way in gases, but not in liquids," said study coauthor Richard Stratt, a chemical theorist at Brown University.

Breaking other laws

The molecule's activity also runs against Newton's third law of motion, which states that for every action there is an equal, but opposite, reaction.

In the new experiment, there water molecules are displaced, but they don't in turn do anything to the peanut molecule.

Friction is important in chemistry. Molecules rub, grind, and bang against each other as they generate heat that speeds up reactions.

Friction in gas reactions is reduced due to the relatively far distances between molecules, but the close proximity of molecules in liquid makes friction nearly unavoidable.

Although the discovery has no immediate practical use, it changes the way scientists think about the 90 percent of all chemical reactions that take place in liquid, Bradforth said.

One potential use could be to manipulate reactions by isolating molecules from their surroundings and reducing the production of useless byproducts.

"The main reason we're so excited by these results is that friction is how energy is shuttled around in chemical reactions," Stratt told LiveScience. "If it doesn't operate, or it operates differently than we always thought, that makes us wonder if there are entirely new ways we ought to be thinking about how chemical reactions take place."

The research is detailed in the March 31 issue of the journal Science.

[Wyrm]

It's interesting behavior, but to say that it "breaks the laws of physics" and "beats friction" is a might exaggeration. After all, the molecule was energized to the equivalent temperature of 8,000 °F, which is about 30-40 times the boiling point of water, so you've got to expect something interesting to happen.

[Sriad]

Yep, there's a sensationalist headline, but the meat of the article seems pretty scientifically plausible. Cool stuff, but no laws of physics broken.

"After the molecule completed about 10 rotations, the shock dwindled and the water molecules rushed back in." COE


"The molecule's activity also runs against Newton's third law of motion, which states that for every action there is an equal, but opposite, reaction.

In the new experiment, there water molecules are displaced, but they don't in turn do anything to the peanut molecule."


The displacement is a bubble, which is to say SPHERICAL, which means all forces on the molocule cancel. OBVIOUSLY there are forces of some sort acting on our little engine that can, because the reaction only lasts "about 10 rotations."

This is pretty cool and quite remarkable in liquid studies, but not as staggering as the article's hyperbolic bullet points make out.

[TheBlackCat]

This is pretty cool and quite remarkable in liquid studies, but not as staggering as the article's hyperbolic bullet points make out.

But can it even be considered a liquid at 8,000 degrees and with an apparently pretty sizable shockwave like that? You think it would flash vaporize the molecules of water right around it, and the pressure wave would also cause some vaporization as the pressure gradient pulled the molecules apart at those small scales.

[Surlethe]

I'm not sure friction has meaning on a molecular level; the impression I've been under is that friction is a macroscopic phenomenon caused by irregularities in surfaces. If this is the case, then isn't it absurd to say a molecule can be free of friction, since it already is? Or have I been under an incorrect presumption?

[Sharpshooter]

I can see it now - the fundies are going to be jumping all over this, screaming "SEE? SEE? IF SCIENCE COULD BE WRONG ABOUT THIS, THEY COULD BE WRONG ABOUT EVOLUTION, TOO!"

[TheBlackCat]

I'm not sure friction has meaning on a molecular level; the impression I've been under is that friction is a macroscopic phenomenon caused by irregularities in surfaces. If this is the case, then isn't it absurd to say a molecule can be free of friction, since it already is? Or have I been under an incorrect presumption?

Friction is actually due to intermolecular forces, not irregular surfaces. In fact, smooth surfaces can have much higher friction than rough ones. For instance there is something called a "cold weld", where two ultra-smooth pieces of metal are placed together in a vacuum. Due to the massive friction involved they lock together and cannot be pulled apart, ultimately fusing entirely. However, if you want to use friction for grinding then you need a rough surface.

[Surlethe]

Friction is actually due to intermolecular forces, not irregular surfaces. In fact, smooth surfaces can have much higher friction than rough ones. For instance there is something called a "cold weld", where two ultra-smooth pieces of metal are placed together in a vacuum. Due to the massive friction involved they lock together and cannot be pulled apart, ultimately fusing entirely. However, if you want to use friction for grinding then you need a rough surface.

So friction can exist between two molecules, rather than only between two macroscopic objects. Thanks.

[TheBlackCat]

Despite its fleeting nature, the reaction managed to smash the linear response theory, a chemistry model that states such a thing can't happen in a liquid environment.

"You can see molecules behave this way in gases, but not in liquids," said study coauthor Richard Stratt, a chemical theorist at Brown University.

I have re-read this and although I am no expert it sounds to me like it is simply pushing the system outside its region of fit (this system was subjected to some really extreme conditions). Pretty much any real linear system is non-linear if you push it far enough outside of its normal operating conditions. That is what its sounds like they did, which may be something no one else has done before but really shouldn't be a surprise.

So friction can exist between two molecules, rather than only between two macroscopic objects. Thanks.

No, friction is by definition between two molecules. The friction we see is simply the sum of the friction between a great many molecules.

From my physics Textbook University Physics by Young and Freedman:

On a microscopic level, friction and normal forces result from the intermolecular forces (fundamentally electrical in nature) between two rough surfaces where they come into contact. The actual area of contact is usually much smaller than the total surface area. As a box slides over the floor, bonds between the two surfaces form and break, and the total number of such bonds varies; hence the kinetic friction force is not perfectly constant. Smoothing the surface can actually increase friction, since more moleules are able to interact and bond; bringing two smooth surfaces of the same metal together can cause a "cold weld." Lubricating oilds work because an oil film between two surfaces (such as the pistons and cylinder walls in a car engine) prevents them crom coming into actual contact.

[Surlethe]

So friction can exist between two molecules, rather than only between two macroscopic objects. Thanks.

No, friction is by definition between two molecules. The friction we see is simply the sum of the friction between a great many molecules.

From my physics Textbook University Physics by Young and Freedman:

<snip>

I stand corrected again. Thank you.

[Mange]

This story I was linked to comes from FOXNews, so take it with plenty of grains of salt.

I read it in an article over at Livescience the day before yesterday.