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Would material cut by a blade 1 molecule thick join back together when the blade was removed?

Not a typical blade that gets wider away from the edge. It’s 1 molecule thick from the edge to the back. Would the molecules that the blade is separating start dragging on the side of the blade eventually and start to cause damage? 

To be clear I am looking for opinions since facts can not exist on something that is fictional. A blades edge 1 molecule thick would not cut a molecule in half so I would assume the path of least resistance would be the space between the molecules. Since you wouldn’t be damaging any matter going in between the molecules couldn’t the molecules just be attracted back together after the blade passes by? On the molecular level I suppose the material would have equal chance of cutting the blade so let’s say the blades molecules are more tightly packed to ensure it does the cutting. I guess at its core my question is whether molecules would join back together after their attraction to one another is severed? I know there are lots of questions in here so just indulge me on the ones you wish to answer. Thank you


Thanks Noname. It doesn’t have to be a blade. It could be a laser or something else 1 molecule thick that can pass between molecules. Your answer reminds me to add another detail. After the cut the material would stay 1 molecule away from each other and not fall apart because the material is being held in that position somehow. Wouldn’t molecular attraction pull the molecules back together?

2 Answers

    Lv 7
    2 months ago
    Favorite Answer

    if it were a laser beam i could see the object maybe not taking any damage...but if it was a blade, perhaps the motion from the blade would be enough to domino everything...if I was drawing it I would make it strings that fall apart from the cut..

    • Brian20 hours agoReport

      Well said. Your description of rolling a diamond in carbon powder is a beautifully simple answer to a complex question. I wasn’t accounting for the energy either. That makes perfect sense that if you use energy to cut something than you would need to put energy back to bring it back together. Thanks

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  • 1 month ago

    Interesting question. The short answer, though, is probably not.

    Let's suppose you have a big tub of carbon powder and a mixer that churns it around. You leave it for 10 years and come back to look at it. What you will have is a big tub of carbon powder. What you won't have are diamonds. One way of explaining why you don't have diamonds is entropy. You start with a disordered high entropy collection of carbon and you want to create a diamond crystal with an ordered arrangement and low entropy. The laws of physics tell us you need to use energy to do that. If you use high temperatures and pressures you might just form a tiny diamond crystal.

    Now imagine you do have a diamond and you put it in the carbon powder and roll it around. What you'll get is a diamond covered in carbon powder. What you won't get is a bigger diamond! Again, you have the same problem. You need to supply energy to get it to form in an ordered arrangement. You might have grown CuCl crystals in school where you take a seed crystal on a string and place it in solution. In this case there is enough thermal energy at room temperature to overcome that entropy. In other cases you are using a chemical reaction to generate that energy and form crystals.

    One interesting thing about crystals is that it is thermodynamically impossible to create one that is perfect. They will always have some defects. They have missing atoms or impurities. They have slips and twists where bits of the crystal don't align right. But they also have surfaces ... since the crystal ends, the structure at the surface is different to the structure deep inside it. In some materials, the fact that it must end means electric fields change through it which causes reordering of the surface and charge transfer.

    So ... you take a material and slice it very cleanly by some method. To do this you had to use energy. And instead of one lump of material in a reasonably low entropy organised state, you have two! You've increased the entropy by breaking those chemical bonds. The material in each half is thinner than it was and now has two new surfaces. Each half will now reorder its structure to compensate for the changes in strain, the change in thickness and the changes in electric fields. The surfaces change configuration from the bulk of the material. And when you try to put it back together, the two halves no longer match. Since you used energy to cut it and increased the entropy, you now need to use energy to get it back the way it was and reduce entropy. 

    This is why chemists and phyicists anneal materials ... they have to heat them to reorder the crystal structure to persuade crystallites to merge to form one crystal.

    The best I've seen is a polymer that can self repair at room temperature. You split it, put the halves together, and it'll repair itself. But the actual repair job is about 7% of the original structure.

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    • Brian20 hours agoReport

      I’m so sorry. The stupid thing glitched after adding my comment to your question and it went back to a different answer which  I accidentally awarded the best answer I was giving to you. I don’t know how to reverse it. If you know how I would be happy to do it. Thanks again

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