An experimental open source memristor / programmable “diode”
bigattichouse.medium.com
bigattichouse.medium.com
As most people know batteries have a limited number of cycles. Every reaction cycle adds some entropy/side reactions, and eventually it will become irreversible. Magnetic storage reorients a crystal or metal, which is more repeatable than a chemical reaction. Our neurons have similar systems to “clean” themselves so they can reset.
I imagine finding a viable memresistor is more about its ability to cycle.
Unless I'm missing something the flux-charge equation that "dPhi = M dq" seems to be the same as that of the resistor as well (since dPhi = vdt we have vdt = Mdq => v = M*i which is just ohm's law assuming a constant M).
> Chua in his 1971 paper identified a theoretical symmetry between the non-linear resistor (voltage vs. current), non-linear capacitor (voltage vs. charge), and non-linear inductor (magnetic flux linkage vs. current). From this symmetry he inferred the characteristics of a fourth fundamental non-linear circuit element, linking magnetic flux and charge, which he called the memristor. In contrast to a linear (or non-linear) resistor the memristor has a dynamic relationship between current and voltage including a memory of past voltages or currents. Other scientists had proposed dynamic memory resistors such as the memistor of Bernard Widrow, but Chua introduced a mathematical generality.
A (fixed) capacitor has a constant capacitance C just like a fixed memristor has a constant memristance M. Both M and C can be used in differential equations involving charge.
Note that it's not unfair to consider any circuit with nonzero memristance as 'containing' a memristor, after all the whole point of fundamental circuit elements is that you can add them to model stuff like wire resistance and stray capacitance. However while you can't create resistance, capacitance and inductance by combining any of the others you can have memristance by combining all 3 (technically you can create any of the 4 by combining the 3 others, but 3 of them can be built easily so those make more sense as fundemental circuit elements).
So while a linear memristor would be rather unusual, I don't quite see what's so fundamental about it as a non-linear circuit element.
In fact, voltage divided by current is resistance, BY DEFINITION.
Hey, you can also take a bunch of resistors, wire them in a loop and proclaim you have successfully emulated inductor with just resistors. That is what you get if you decide to set aside rules.
Important part of the description of what is memristor is its dependence on past charge flown through it, you can't decide to ignore parts of definition whenever it suits your argument.
For a linear resistor sure, but otherwise resistance is better defined as the slope.
And well if you don't like that definition of memristance I suggest you update the corresponding wikipedia article.
> Hey, you can also take a bunch of resistors, wire them in a loop and proclaim you have successfully emulated inductor with just resistors. That is what you get if you decide to set aside rules.
A circle of resistors has 0 inductance by definition. In practice it's pretty tricky to build such a circuit using 0 inductance wire in an impermeable environment so it remains an approximation.
https://medium.com/@bigattichouse/an-experimental-open-sourc...
He patented a memristor design, and seemingly has some wild ideas stemming from his work with them.
> My statement stems from our work with AHaH Computing. When two energy-dissipating pathways compete for conduction resources, a Knowm synapse (aka kT-Bit) will emerge and it can be shown that the pair maximizes power dissipation while driving Hebbian or Anti-Hebbian learning. We see this building block for self-organized structures throughout Nature, for example in arteries, veins, lungs, neurons, leaves, branches, roots, lightning, rivers and mycelium networks of fungus. > > We observe that in all cases there is a particle that flows through competitive energy dissipating assemblies. The particle is either directly a carrier of free energy dissipation or else it appears to gate access, like a key to a lock, to free energy dissipation of the units in the collective. Some examples of these particles include water and sugars in plants, ATP in cells, blood in bodies, neurotrophins in neurons, and money in economies. In the cases of whirlpools, hurricanes, tornadoes and convection currents we note that although the final structure does not appear to be built of competitive structures, it is the result of a competitive process with one winner; namely, the spin or rotation. In other words, a hurricane is a ‘collapsed kT-Bit’.
And case of those could have a billion memristors.
https://www.directwatertanks.co.uk/50000-litre-vertical-grp-...
I wonder if this means it is undoable.
1. Cover the LED so it cannot be hit by light 2. Charge it in reverse bias to write a 1 or do nothing to write a 0
inverting the polarity and reading the + you detect a voltage for up to 3-5 seconds depending on the diode if a 1 was written in earlier :)
https://en.wikipedia.org/wiki/Williams_tube
> The Williams tube works by displaying a grid of dots on a cathode ray tube (CRT). Due to the way CRTs work, this creates a small charge of static electricity over each dot. The charge at the location of each of the dots is read by a thin metal sheet just in front of the display. Since the display faded over time, it was periodically refreshed. It cycles faster than earlier acoustic delay line memory, at the speed of the electrons inside the vacuum tube, rather than at the speed of sound. However, the system was adversely affected by any nearby electrical fields, and required constant alignment to keep operational. Williams–Kilburn tubes were used primarily on high-speed computer designs.
Is this the first feasible memristor?
[1] https://en.wikipedia.org/wiki/Memristor#The_memristor_as_a_f...
Grab the zip from github, unzip it, and point chrome to it as an 'unpacked extension'. Works perfectly and takes 2 minutes.
The github is here https://github.com/tom-james-watson/old-reddit-redirect
You lose automatic update but that's a feature in this case.
- This is a Firefox Extension
- Why not just ... disable automatic updates?
I don't get why people keep complaining about New Reddit when you can just do this once and problem solved.