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Russell Nash
09-03-2010, 07:53 PM
http://www-03.ibm.com/ibm/history/exhibits/vintage/images/4506VV1003.jpg

"IBM scientists discovered how to move and position individual atoms on a metal surface using a scanning tunneling microscope."

IBM Archives: "IBM" atoms (http://www-03.ibm.com/ibm/history/exhibits/vintage/vintage_4506VV1003.html)

However, I managed to do something similar without such expensive equipment.

http://www.ligotti.net/picture.php?albumid=162&pictureid=2251

Russell Nash
09-04-2010, 06:39 PM
Apparently there was a mistake with the picture, here it is again,

http://www.ligotti.net/picture.php?albumid=162&pictureid=2252
http://img709.imageshack.us/img709/637/4506vv1003.jpg

You can clearly read "LIGOTTI". But I did it with "Paint", and it took me less than 10 minutes to do it. I'm not saying that these guys at IBM used Paint too, of course not!;), but allow me to doubt such scientific advancements when proof is so scarce (and easy to duplicate).

This article also claims that some scientists have taken pictures of atoms:drunk:. Allow me to doubt similar experiments. I'm from an old generation when a picture is not enough evidence, especially in this computerized era.

New Microscope Reveals the Shape of Atoms: Scientific American (http://www.scientificamerican.com/article.cfm?id=the-shape-of-atoms)

Robin Davies
09-05-2010, 08:41 AM
I'm not saying that these guys at IBM used Paint too, of course not!;), but allow me to doubt such scientific advancements when proof is so scarce (and easy to duplicate).

This article also claims that some scientists have taken pictures of atoms:drunk:. Allow me to doubt similar experiments. I'm from an old generation when a picture is not enough evidence, especially in this computerized era.
Given that any scientific results can be faked, what do you accept as good evidence?

Russell Nash
09-05-2010, 02:20 PM
Given that any scientific results can be faked, what do you accept as good evidence?

Precisely. Robin, I would say: my eyes, my ears, to be there while the experiment is being done, but even then... David Copperfield made the Statue of Liberty disappear live on TV. Live! And we all know that it is not possible.

Let me add, if IBM specifies which equipment was used (names, model, etc), where this was done (place and date), which conditions are required (temperature, etc), which university backs it up (Princeton, Cambridge, etc?), who supervised the experiment (names, degrees, etc), what scientific procedure produces this result (that can be duplicated anywhere else given certain conditions), then I would say that this news is serious.

Derek
09-05-2010, 04:10 PM
Speaking as a practising scientist, the essence of any reputable published research is twofold: it must be peer-reviewed and it must contain sufficient experimental details for others to repeat the work.

Unreproducible research is rapidly consigned to the dustbin of history. For example: cold fusion, MMR/autism etc.

Russell Nash
09-05-2010, 07:14 PM
Unreproducible research is rapidly consigned to the dustbin of history.

According to the New York Times, April 5, 1990, "...scientists had spelled out the company's initials by dragging single atoms into the desired pattern on the surface of a crystal of nickel."

2 Researchers Spell 'I.B.M.,' Atom by Atom - NYTimes.com (http://www.nytimes.com/1990/04/05/us/2-researchers-spell-ibm-atom-by-atom.html)

But, Scientific American, Dec. 2009, 20 years later, claims that "...Igor Mikhail­ovskij and his collaborators at the Kharkov Institute of Physics and Technology in Ukraine have imaged the shapes of those orbitals in carbon atoms by improving an old imaging technique called field-emission microscopy."

What I cannot understand is whether the image given by IBM represents individual atoms, or not. The blue image shows bell-shaped atoms. Therefore, are they atoms? Or, as I understood it, impacts of single atoms on a nickel sheet. The article also says: "...by firing patterns of bullets into walls to spell out the initials of potential customers. In a similar vein, I.B.M. announced yesterday that its scientists had spelled out..." giving to understand that the same technique was used. The blue sheet has different irregularities smaller than the size of atoms, what are they?, if the bell-shaped impacts are indeed done by atoms being fired on a nickel sheet.

But, if the blue sheet is made of nickel, then definitely the bell-shaped objects are impacts of single atoms, not actual atoms. ...?

The news by Scientific American also presents several problems, and one of them is to know how this image was produced. I have the idea (perhaps wrong?) that a particle can only be observed or photographed if there was an impact between a photon and that given particle. If the orbitals represent the probability to find an electron on a given atomic orbit, I don't see how these Ukrainian scientists got this blurry blue image representing a whole orbital and not just a point-like impact. To have such image, I understand that a photon should be impacting an electron hundreds of times, did I understand wrong...?

Derek
09-06-2010, 08:37 AM
As I understand it the technique used is similar to Atomic Force Microscopy
Atomic force microscopy - Wikipedia, the free encyclopedia.

The pictures are not 'photographs', but rather a topographical representation of the miniscule forces between the tip of the probe and the surface which allows atomic level resolution. The resolution of light microcopes is restricted by the 'diffraction limit', hence 'electron microscopes'.

Robin Davies
09-06-2010, 08:37 AM
The news by Scientific American also presents several problems, and one of them is to know how this image was produced. I have the idea (perhaps wrong?) that a particle can only be observed or photographed if there was an impact between a photon and that given particle. If the orbitals represent the probability to find an electron on a given atomic orbit, I don't see how these Ukrainian scientists got this blurry blue image representing a whole orbital and not just a point-like impact. To have such image, I understand that a photon should be impacting an electron hundreds of times, did I understand wrong...?
According to the article the image is produced by the electrons being pulled off by an electric field and hitting a screen which presumably registers their impact in some way. Photons are not impacting the electrons under observation.

Russell Nash
09-06-2010, 01:56 PM
As I understand it the technique used is similar to Atomic Force Microscopy
Atomic force microscopy - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/Atomic_force_microscopy).

The pictures are not 'photographs', but rather a topographical representation of the miniscule forces between the tip of the probe and the surface which allows atomic level resolution. The resolution of light microcopes is restricted by the 'diffraction limit', hence 'electron microscopes'.

Thanks.

On this article, the section: "Identification of individual surface atoms", shows a picture with this legend: "the atoms of a sodium chloride crystal viewed with an atomic force microscope".

File:AFM view of sodium chloride.gif - Wikipedia, the free encyclopedia (http://en.wikipedia.org/wiki/File:AFM_view_of_sodium_chloride.gif)

Is it correct to understand that the white dots are atoms? Not atoms being photographed but as you said "...a topographical representation of the miniscule forces between the tip of the probe and the surface"? But, if this is true, if the picture shows a graphical interaction between a probe and atoms, then the article by Scientific American saying that someone has photographed atoms makes no sense. Isn't it a picture of sodium chloride at an atomic level? So, in a way, atoms were already "photographed". Derek, do you know what those irregularities on the IBM picture are? Beside the bell-shaped objects, one can see smaller irregular shapes, what are they? If these bell-shaped represent interactions with atoms, what do the other shapes (smaller than the radius of an atom) represent?


According to the article the image is produced by the electrons being pulled off by an electric field and hitting a screen which presumably registers their impact in some way. Photons are not impacting the electrons under observation.

Robin, we can only see something, an atom in this case, if and only if it interacts with something else. The screen is also made of atoms. So, if a carbon atom interacts with a screen, to see its "shape", not just a point-like image, we need a screen made of something even smaller that registers the interaction. If a carbon atom interacts or impacts a screen made of carbon atoms (for example) we would only see an impact, just point-like impact. Scientific American provides a shape, this is what amazes me. How did they get this shape? By seeing a screen? But we are at an atomic level. The screen is made of atoms and I don't see how they can get an actual photograph, not just a topographical view, as Derek said.

Derek
09-07-2010, 07:58 AM
I do remember a lot of people at the time raising their eyebrows at the 'shadows' visible in the original IBM picture, which suggested the image had been digitally manipulated to make it look more 'aesthetic'. In fact, the shadows turned out to be a genuine artifact of the way the raw data was processed. Perhaps the fine 'grid' you can see below might be the same. I can't remember if the atoms on the surface are of the same element as the surface itself - the atomic radii of different elements can vary quite a bit as you go down the periodic table, which might explain the difference in size.

As for SA claiming that the modern day scientists have 'photographed' atoms, I suspect this may be a case of oversimplification for a general audience. Electrons are many orders of magnitude smaller than an atom so the technique is not unfeasible. But there must have been some 'gain' or other magnification technique applied to the electrons before they hit the screen (or the screen was a suitably long distance away) otherwise you would only get a microscopic image!

Russell Nash
09-07-2010, 05:27 PM
In fact, if the news were "Princeton atoms", atoms arranged in a way that one reads PRINCETON on the screen, it would sound serious. I trust prestigious institutions, but not IBM. I don't know how much the technique costs but if true, which I don't doubt it is true at all, why would IBM spend any money to arrange certain atoms in a certain way? Having a semi-naked baywatch girl sitting on an IBM machine would produce much better and cheaper results.

The second one from SA is hard to believe unless they provide more pictures and specify the technique used. Everything is possible, it probably is, but allow me to doubt this one in the meantime. I had the idea that atoms cannot be photographed. Period. But, if someone did it, and the evidence is verifiable, then I'll believe it. The problem with some scientific discoveries is that magazines publish so many articles that one doesn't have time to verify all that one reads. See this one, for example:

http://www.ufologie.net/htm/ancural2.htm

When I read it, I was shocked. Wow! I said. It sounds like a story by John Varley. Time travelers or ETs taking away or leaving things behind. But, after all, the answer was very conventional: all this debris came from a nearby factory. That's way I became very skeptic with what I read.