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Comment by danmaz74 | Hacker News Reader

Interestingly, this is exactly what the chief of HP labs said in this video [1]: That lots of papers noted the effect and talked about anomalies, but no-one made the connection to the memristors before them. He also says that the effect is only really noticeable at nano scales (because it needs incredibly high electric fields).

EDIT: on second thought, that's not the case, because the HP memristor is not a memristor in the sense of the of the original paper describing it - it has nothing to do with the magnetic flux. It can only be described with the same set of equations, so, it behaves like a memristor, but is not "actually" a memristor that completes the set [2]. That is, if I understood the video correctly (but I think I did, as the speaker himself talked about a "trick" in the beginning of the video).

[1] https://www.youtube.com/watch?v=bKGhvKyjgLY [2] http://en.wikipedia.org/wiki/Memristor#mediaviewer/File:Two-...

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Nice to see confirmation of that theory from that high up.

It seemed extremely logical to me when I heard it the first time and like everything else, in retrospect it is blindingly obvious.

I'd hate to see a memristor dropped into a circuit design and being handed the task of 'fixing' spice to produce the correct output. But by the looks of it the usefulness of individual memristors will be quite limited.

Can't reply to your other comment yet, so I'll do it here. I think that this is a "duck typing" memristor: You can use it as a memristor, but it's not what was predicted. Anyway, if you're interested, watch the video I linked (thanks to @achille): It really explains what this is all about. If you have some basic understanding of semiconductors physics I think you'll enjoy it :)

I think I get what you're going for now, sorry it took a while for the coin to drop.

Just like a battery can look like a capacitor under some conditions it really isn't a capacitor.

Capacitors and batteries can be described using the same basic laws, even though the fundamental mode of operation is completely different.

They have the same basic properties:

- internal resistance

- a certain capacity

- a breakdown voltage

- you can charge them

- you can discharge them by connecting the terminals (hopefully through some suitable load)

- both exhibit self-discharge

- have a certain amount of inductance

And yet the one is a real capacitor whereas the other one is an electro-chemical device, only when you open one up or when you charge/discharge it a large number of times can you see that there is a real difference between the two, superficially they are interchangeable for some applications.

Does that get it right?

An electrolytic capacitor is an electro-chemical device itself. Also, like a battery, if the "electrolyte" is not without solvent then it is a liquid-state device. As opposed to a film & foil capacitor which is a solid-state device. Batteries generate a characteristic cell voltage as a result of a chemical reaction. Capacitors store any voltage up to their maximum rating, electrolytics have higher capacity/size ratio than film & foil due to the chemical help of the electrolyte, but do not generate voltage on their own, only store what is supplied from a power source.

That's a good comparison, as far as I understand this thing. With the exception that the "real memristor" is only a theoretical device.

See my edit to the previous comment - now I actually think that the symmetry isn't proven by HP approach (but this doesn't make it any less interesting/promising).

For it to be an actual memristor it would have to be. Really curious about what it is that they will be unveiling.

Is it not "actually" a memristor in the same sense that an electrochemical capacitor is not "actually" a capacitor: it exhibits the same properties as a capacitor, but the properties are caused by redox reactions instead of electric fields (even though most chemistry is really just electric fields anyway)?

You can produce memristors on the macro scale[1], in fact, it appears that any pair of oxidized conductive metals will work[2].

http://sparkbangbuzz.com/memristor/memristor.htm[1]

http://youtu.be/rvA5r4LtVnc[2]

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