4 ms·

Unless I've missed something, it also seems to be news to Professor Troy Shinbrot of Rutgers University.

Jach 13y ago
No, Troy is the link. http://phys.org/news/2012-06-rutgers-granular-slip-documents-voltage-video.html http://phys.org/news/2012-06-rutgers-granular-slip-documents... (So after 2 years he still has no idea on how it's happening?)
- tehwalrus 13y ago
  Ah, if they were writing about it 2 years ago already, then their result may be the one that was repeated in front of me - curse the mainstream media's "new! new!" language in their copy. the abstract from that paper is very informative as to the context: "It has been known for over a century that electrical signals are produced by material failure, for example during crack formation of crystals and glasses, or stick-slip motion of liquid mercury on glass. We describe here new experiments revealing that slip events in cohesive powders also produce electrical signals, and remarkably these signals can appear significantly in advance of slip events. We have confirmed this effect in two different experimental systems and using two common powdered materials, and in a third experiment we have demonstrated that similar voltage signals are produced by crack-like defects in several powdered materials."
  - samstave 13y ago
    Interesting that this is likely also very related (or the exact same) as when peeling scotch tape, that mechanical action produces x-rays. What about the thought of Chi; could the electric impulses commonly thought of for centuries by martial artists and meditators be an electrical output of some mechanical function of the body?
    - tehwalrus 13y ago
      Chi - only of breaking your arm. The energy being released is from fracture, i.e. bonds breaking, in all but the granular case. Indeed, even granular pack breakup could well involve sympathetic local charging, especially for packs gradually compressed and stressed like soils.

Jach 13y ago

No, Troy is the link. http://phys.org/news/2012-06-rutgers-granular-slip-documents-voltage-video.html http://phys.org/news/2012-06-rutgers-granular-slip-documents... (So after 2 years he still has no idea on how it's happening?)

tehwalrus 13y ago
Ah, if they were writing about it 2 years ago already, then their result may be the one that was repeated in front of me - curse the mainstream media's "new! new!" language in their copy. the abstract from that paper is very informative as to the context: "It has been known for over a century that electrical signals are produced by material failure, for example during crack formation of crystals and glasses, or stick-slip motion of liquid mercury on glass. We describe here new experiments revealing that slip events in cohesive powders also produce electrical signals, and remarkably these signals can appear significantly in advance of slip events. We have confirmed this effect in two different experimental systems and using two common powdered materials, and in a third experiment we have demonstrated that similar voltage signals are produced by crack-like defects in several powdered materials."
- samstave 13y ago
  Interesting that this is likely also very related (or the exact same) as when peeling scotch tape, that mechanical action produces x-rays. What about the thought of Chi; could the electric impulses commonly thought of for centuries by martial artists and meditators be an electrical output of some mechanical function of the body?
  - tehwalrus 13y ago
    Chi - only of breaking your arm. The energy being released is from fracture, i.e. bonds breaking, in all but the granular case. Indeed, even granular pack breakup could well involve sympathetic local charging, especially for packs gradually compressed and stressed like soils.