11 ms·

Memristor – The fictional circuit element

193 points by godelmachine 8y ago

bacon_waffle 8y ago
Pragmatic engineer's version: digikey shows 0 search results for "memristor". (funny enough, doing the same at aliexpress yields a young kid's plastic ball ad, containing "Warning:Memristor")
- Aardwolf 8y ago
  At least you can try out a fictional one here: http://www.falstad.com/circuit/e-mr.html http://www.falstad.com/circuit/e-mr.html
  - deleted 8y ago
    [deleted]
- tgragnato 8y ago
  Practical engineering: SPICE models - https://knowm.org/memristor-models-in-ltspice/ https://knowm.org/memristor-models-in-ltspice/ - https://knowm.org/the-pershin-voltage-threshold-memristor-model-in-ngspice/ https://knowm.org/the-pershin-voltage-threshold-memristor-mo... - https://knowm.org/the-joglekar-resistance-switch-memristor-model-in-ltspice/ https://knowm.org/the-joglekar-resistance-switch-memristor-m...
- minxomat 8y ago
  According to [1], RRAM is a form of memristor*. You can buy these at DigiKey [2]. However, I can't really think of a practical application. It's about 10x slower than (P)SRAM. [1] - https://en.wikipedia.org/wiki/Resistive_random-access_memory https://en.wikipedia.org/wiki/Resistive_random-access_memory [2] - https://www.digikey.com/products/en/integrated-circuits-ics/memory/774?k=reram https://www.digikey.com/products/en/integrated-circuits-ics/... > Leon Chua argued that all two-terminal non-volatile memory devices including ReRAM should be considered memristors. Stan Williams of HP Labs also argued that ReRAM was a memristor. However, others challenged this terminology and the applicability of memristor theory to any physically realizable device is open to question. Whether redox-based resistively switching elements (ReRAM) are covered by the current memristor theory is disputed.
- taneq 8y ago
  > (funny enough, doing the same at aliexpress yields a young kid's plastic ball ad, containing "Warning:Memristor") Happy Fun Ball may contain one or more memristors, and may or may not be sentient as a result. It is recommended to treat Happy Fun Ball with respect as a precaution.
  - mchannon 8y ago
    For those among us 30 and younger who are too young to get the joke, https://en.wikipedia.org/wiki/Happy_Fun_Ball https://en.wikipedia.org/wiki/Happy_Fun_Ball
- mindcrime 8y ago
  I went a step further a while back and emailed Digikey to see if they had any insight on memristor availability. This is what I got back: Thank you for contacting Digi-Key with your request about Memristor parts. While none of Digi-Key official supplies have any existing memristor parts available, there a few companies that have made experimental development chips available for sale. https://knowm.org/product/bs-af-w-memristors https://knowm.org/product/bs-af-w-memristors http://www.bioinspired.net/products-1.html http://www.bioinspired.net/products-1.html Seems like general availability of a real memristor is still a ways off - if at all.
  - no_identd 8y ago
    That last link is dead, and here is why: https://knowm.org/bio-inspired-technologies-neuro-bit-memristors-acquired-by-knowm/ https://knowm.org/bio-inspired-technologies-neuro-bit-memris...
    - mindcrime 8y ago
      Heh, interesting. Not that all the saber-rattling about patent violations particularly makes me want to do business with Knowm.
devnull791101 8y ago
i seem to remember HP having made these a number of years ago
- jacobush 8y ago
  https://www.hpcwire.com/2015/06/11/hp-removes-memristors-from-its-machine-roadmap-until-further-notice/ https://www.hpcwire.com/2015/06/11/hp-removes-memristors-fro... But what they watered it down to (and not delivered on that either) seems to be roughly equivalent to that fancy flash memory you can buy now for the new intel chipsets.
  - cmiles74 8y ago
    It's unclear to me if the problem was a lack of vision on the part of HP or if the technology they came up with has fundamental problems that prevent it from being practical. Either one seems plausible.
    - jacobush 8y ago
      Don't know either. But if you google for something like - memristor oxygen transfer problem - lots of stuff comes up.
- nabla9 8y ago
  HP's lab (Stanley Williams) made their memristor announcement 10 years ago. "The missing memristor found" https://www.nature.com/articles/nature06932 https://www.nature.com/articles/nature06932 and still working on it "Capacitive neural network with neuro-transistors" https://www.nature.com/articles/s41467-018-05677-5 https://www.nature.com/articles/s41467-018-05677-5
- cmiles74 8y ago
  This article from Ars Technica talks a little bit about memristors and HP's plans for "The Machine". The original plan was for The Machine to demonstrate this technology, but HP ended up removing feature after feature (including memristor technology) before it's release. They quote John Sontag from HP in the article: "The simplest way to think about it is this—take a DRAM DIMM out, and put a memristor DIMM in,” said Sontag. “You now have another pool of memory that’s denser and nonvolatile. It’s a new class of memory—the consequence for operating systems is that moving stuff around from I/O devices [to and from disk] becomes unnecessary." https://arstechnica.com/information-technology/2014/06/hp-labs-machine-dissolves-the-difference-between-disk-and-memory/ https://arstechnica.com/information-technology/2014/06/hp-la...
leni536 8y ago
> A nonlinear ϕ-q curve will always have a positive, albeit variable slope. However, the ratio of ϕ to q still has the units of ohm, without a phase shift, making this a nonlinear resistor. I think this is false. A nonlinear ϕ-q curve will yield a resistance which depends on time in a manner that can't be described by a single nonlinear v-i curve.
contravariant 8y ago
I disagree with their claim that current is the time derivative of charge.
- InitialLastName 8y ago
  Are you being as pedantic as to ask for "through an area"? Because that's literally the defined relationship between current and charge.
  - contravariant 8y ago
    This isn't mere pedantry, there is a difference between current and the time derivative of charge, I don't mind that they prefer to use one or the other, but if you insist on making a periodic table then you've got to take both into account. It's also an especially bad idea to claim the time derivative of current is the the double derivative of charge, given that these are two very different notions of derivative. To clarify, claiming current is the derivative of charge is like claiming the current of a river is the derivative of it's water level.
    - lnx01 8y ago
      Current is unequivocally the time derivative of charge. There're no two ways about it. i(t) = dQ(t) / dt "To clarify, claiming current is the derivative of charge is like claiming the current of a river is the derivative of it's water level." This statement is wrong, while water in some cases provides a decent analogy for electricity, this is not one of them.
      - contravariant 8y ago
        If I have a piece of wire with a constant current through it the charge everywhere on the wire remains constant. In fact the charge will be more or less neutral in most cases. Note that the alternative would be that the wire somehow accumulates charge as it passes current, which clearly isn't happening.
mchannon 8y ago
Fictional or no, this company sells them: https://knowm.org/memristors/ https://knowm.org/memristors/
- deleted 8y ago
  [deleted]
- mfer 8y ago
  You can buy them. Sometimes under branding that doesn't say memrister. You can learn how they work and the science (see the video on https://knowm.org/memristors/ https://knowm.org/memristors/) Are they a fundamental circuit element or one of the existing fundamental elements? We can let scientists debate that.
  - VikingCoder 8y ago
    Yeah, I'm really lost. I feel like someone described useful properties of A Thing if it existed. Then we figured out how to make A Thing that had those useful properties. Is it A Thing, or Two Things? That's pedantic. Pragmatically, don't we have the useful properties?
    - cptaj 8y ago
      Don't be too quick to call academics pedantic. You're probably missing some key facts of the argument that make the distinction relevant.
      - mehrdadn 8y ago
        I agree with this. That said, the Wikipedia article has something interesting to point out regarding this [1]: > Martin Reynolds, an electrical engineering analyst with research outfit Gartner, commented that while HP was being sloppy in calling their device a memristor, critics were being pedantic in saying that it was not a memristor. [1] https://en.wikipedia.org/wiki/Memristor#Memristor_definition_and_criticism https://en.wikipedia.org/wiki/Memristor#Memristor_definition...
    - 8y ago
hatsunearu 8y ago
tldr + spoilers: there doesn't seem to be a mechanism for memristors to exist without significant nonlinearity or being a fully passive device, so it's kind of hard to say it's a fundamental circuit element
appleflaxen 8y ago
I went down the rabbit hole. Best terminal branches I found are: * HP created something they claimed was a memristor [1] * there were thermodynamic arguments about why it wouldn't work [2] * HP discontinued the architecture based on the component [3] 1. https://arstechnica.com/information-technology/2014/06/hp-labs-machine-dissolves-the-difference-between-disk-and-memory/ https://arstechnica.com/information-technology/2014/06/hp-la... 2. https://arxiv.org/ftp/arxiv/papers/1207/1207.7319.pdf https://arxiv.org/ftp/arxiv/papers/1207/1207.7319.pdf 3. https://www.theregister.co.uk/2016/11/29/hp_labs_delivered_machine_proof_of_concept_prototype_but_machine_product_is_no_more https://www.theregister.co.uk/2016/11/29/hp_labs_delivered_m...
- no_identd 8y ago
  Well... One thing about the OP paper smells very fishy to me: About two years ago, an extremely important result about Memristors and the notion of circuit elements in general came out. Unfortunately, it didn't get a lot of attention, and remains not-that-well-known even among experts. But: Anyone making claims like the OP paper would HAVE TO consider it in their model if they want to get taken serious. Here's the paper: https://hal.archives-ouvertes.fr/hal-01322396/document https://hal.archives-ouvertes.fr/hal-01322396/document Abdelouahab, Mohammed-Salah; Lozi, René; Chua, Leon O. - Memfractance: A Mathematical Paradigm for Circuit Elements with Memory [2016] The fact that the OP paper doesn't even mention Memfractance makes me highly suspicious, and doubly so as the OP paper also brings up a "periodic table" of circuit elements - something the Memfractance paper also does (embedded in ℝ²), but uh... let's say with a lot more behind it. In fact, I'll quote the entire "Conclusions" section of the Memfractance paper here: >In this paper, we have used fractional calculus in order to generalize and provide a mathematical frame for circuit elements with memory: memfractance. We have emphasized that the memfractance is a general paradigm for unifying and enlarging the family of memristive, memcapacitive and memin ductive elements. The motivation and significance of this paper is that there may exist future nano-electronics devices that are more realistically modeled with memfractance elements >We have generalized the definition of fractance which was first introduced in 1983, and after that, introduced the paradigm of memfractance which is fitted for circuit elements with memory such as memristor, meminductor, memcapacitor and second-order memristor first introduced here. We have defined a new element called memfractor which possesses interpolated characteristics between those four circuit elements. >We have then generalized Ohm’s law to memfractor and proved it. A particular, albeit wide-ranging, case of memfractance: the interpolated memfractance has been carefully studied through several numerical illustrative examples. Special attention has been devoted to the interpolated char- acteristic of a memfractor lying between memristor and memcapacitor which exhibits an unexpected new behavior of time variation of flux (φ–t curve). This phenomenon has been studied very carefully by the means of rigorous proofs. >Finally, following Chua’s recent work in which an infinite discrete family of circuit elements: the (α,β) element is introduced in the scope of developing a rigorous mathematical theory of nonlinear circuits, we extend the previous generalized Ohm’s law in order to embed memfractors elements into this periodic table. For this aim, we define an infinite continued family of circuit elements including circuit elements with memory (such as second-order memcapacitor and meminductor and third-order memristor), with a special metric. We call this family: fractional circuit element family. Note: That last passage is a reference to this specific paper: https://www.semanticscholar.org/paper/The-Fourth-Element-Chua/2d194f8216afbd5c9999b0931b9b75d47f923c51 https://www.semanticscholar.org/paper/The-Fourth-Element-Chu... - Chua, Leon O. - The Fourth Element [2012] Which the OP paper also doesn't cite. To me, this looks like a FUD campaign by Intel. I also briefly glanced over the OP paper besides checking for citations in it, and found this passage: "We have borrowed the expression “periodic table” as attributed to Chua" - which cites a secondary resource from 2008, before Chua's two above papers. Looking for any words starting with, or containing a fragment of, "fract" in the paper also yields no results. Looks like the typical outcome of someone who thinks they don't suck at literature research, but does suck at literature research, which, quite honestly, the vast majority of scientists do. Ask a randomly sampled researcher if they ever heard the term "Main path analysis" and they'll stare at you like a deer staring into headlights. Having said that: The paper does seem to bring up a few valid points, e.g. people making errors & drawing bad conclusions from mislabeled diagrams. This isn't an issue in Chua's work, however. Oh, and: Here, some slides on memfractance: http://slideplayer.com/slide/3869533/ http://slideplayer.com/slide/3869533/ Edit: Actually, this got generalized even further in early 2017: https://www.sciencedirect.com/science/article/pii/S1007570416301988 https://www.sciencedirect.com/science/article/pii/S100757041... Machado, J.Tenreiro; Galhano, Alexandra M. - Generalized two-port elements
DonHopkins 8y ago
My favorite fictional-sounding-but-real storage device is the Stringy Floppy! When I hung out at Radio Shack after school to play with the TRS-80's, some guy came by and showed his off, and I was in awe, and so jealous at how fast it was! I was sure that Stringy Floppies were the wave of the future. You didn't need to rewind them like tapes, because they wound back around!!! https://en.wikipedia.org/wiki/Exatron_Stringy_Floppy https://en.wikipedia.org/wiki/Exatron_Stringy_Floppy https://www.youtube.com/watch?v=EBfNy021K2Q https://www.youtube.com/watch?v=EBfNy021K2Q Then there was the Transputer! https://en.wikipedia.org/wiki/Transputer https://en.wikipedia.org/wiki/Transputer
- rtkwe 8y ago
  > You didn't need to rewind them like tapes, because they wound back around!!! You physically can't because they spool from the center like an 8-track tape. Probably why they didn't catch on rewinding lets you treat it more like a really slow hard drive.
- aidenn0 8y ago
  The Transputer is a success; a lot of the ideas developed for it are mainstream today, even if we don't call it a transputer. Kind of like all of the ideas from AI in the 70s and 80s that worked we don't call AI anymore.
jamesough 8y ago
Heard on grape vine that IBM claim to have pulled first silicon for a memristor RPU (design like below) just over a month ago. https://www.nature.com/articles/s41586-018-0180-5 https://www.nature.com/articles/s41586-018-0180-5
usernam33 8y ago
I dream of a bright Future where my PC will have no ram, hdd or ssd but only memristor memory. No need for booting or shutdown, I just add power and everything will be the same as it was when last used. Since I first read about them years ago this is still what I am waiting for even if it does not seem to be at grasp.
- radarsat1 8y ago
  Any reason this can't be done with flash? I wonder what the speed of a flash-RAM computer would be. I'm sure it'd be slow but it'd be interesting. You'd still have to dump and restore the CPU registers of course.
  - mikepurvis 8y ago
    I think the main issues are that it would be crazy slow, and flash isn't really random access for write— you still have to blank whole pages at a time, so you'd definitely still want a RAM caching layer in front of the flash, even if it was being synced on a second by second basis. Plus the whole wear levelling thing would have a huge impact on lifespan. Tiny microcontrollers would be the first ones to benefit from an all-flash architecture, but they all still ship with both flash and RAM onboard.
    - dfox 8y ago
      NAND flash isn't random access even for reading, but generally these limitations are not inherent in the technology, but are motivated by reducing the die area per bit of storage (and thus cost). Purely random access "Flash" is typically called EEPROM and readily available with SRAM-compatible interface (and costs several times more than SRAM). In the microcontroller space there is for example TI's MSP430FR series which has unified non-volatile storage based on what could be described as core-memory on chip.
- SamReidHughes 8y ago
  You've got to be able to reboot for when program bugs leave your memory in an invalid state.
grillvogel 8y ago
more like memeristor
deleted 8y ago
[deleted]

193 points by godelmachine 8y ago

Pragmatic engineer's version: digikey shows 0 search results for "memristor". (funny enough, doing the same at aliexpress yields a young kid's plastic ball ad, containing "Warning:Memristor")

Aardwolf 8y ago
At least you can try out a fictional one here: http://www.falstad.com/circuit/e-mr.html http://www.falstad.com/circuit/e-mr.html
- deleted 8y ago
  [deleted]
tgragnato 8y ago
Practical engineering: SPICE models - https://knowm.org/memristor-models-in-ltspice/ https://knowm.org/memristor-models-in-ltspice/ - https://knowm.org/the-pershin-voltage-threshold-memristor-model-in-ngspice/ https://knowm.org/the-pershin-voltage-threshold-memristor-mo... - https://knowm.org/the-joglekar-resistance-switch-memristor-model-in-ltspice/ https://knowm.org/the-joglekar-resistance-switch-memristor-m...
minxomat 8y ago
According to [1], RRAM is a form of memristor*. You can buy these at DigiKey [2]. However, I can't really think of a practical application. It's about 10x slower than (P)SRAM. [1] - https://en.wikipedia.org/wiki/Resistive_random-access_memory https://en.wikipedia.org/wiki/Resistive_random-access_memory [2] - https://www.digikey.com/products/en/integrated-circuits-ics/memory/774?k=reram https://www.digikey.com/products/en/integrated-circuits-ics/... > Leon Chua argued that all two-terminal non-volatile memory devices including ReRAM should be considered memristors. Stan Williams of HP Labs also argued that ReRAM was a memristor. However, others challenged this terminology and the applicability of memristor theory to any physically realizable device is open to question. Whether redox-based resistively switching elements (ReRAM) are covered by the current memristor theory is disputed.
taneq 8y ago
> (funny enough, doing the same at aliexpress yields a young kid's plastic ball ad, containing "Warning:Memristor") Happy Fun Ball may contain one or more memristors, and may or may not be sentient as a result. It is recommended to treat Happy Fun Ball with respect as a precaution.
- mchannon 8y ago
  For those among us 30 and younger who are too young to get the joke, https://en.wikipedia.org/wiki/Happy_Fun_Ball https://en.wikipedia.org/wiki/Happy_Fun_Ball
mindcrime 8y ago
I went a step further a while back and emailed Digikey to see if they had any insight on memristor availability. This is what I got back: Thank you for contacting Digi-Key with your request about Memristor parts. While none of Digi-Key official supplies have any existing memristor parts available, there a few companies that have made experimental development chips available for sale. https://knowm.org/product/bs-af-w-memristors https://knowm.org/product/bs-af-w-memristors http://www.bioinspired.net/products-1.html http://www.bioinspired.net/products-1.html Seems like general availability of a real memristor is still a ways off - if at all.
- no_identd 8y ago
  That last link is dead, and here is why: https://knowm.org/bio-inspired-technologies-neuro-bit-memristors-acquired-by-knowm/ https://knowm.org/bio-inspired-technologies-neuro-bit-memris...
  - mindcrime 8y ago
    Heh, interesting. Not that all the saber-rattling about patent violations particularly makes me want to do business with Knowm.

devnull791101 8y ago

i seem to remember HP having made these a number of years ago

jacobush 8y ago
https://www.hpcwire.com/2015/06/11/hp-removes-memristors-from-its-machine-roadmap-until-further-notice/ https://www.hpcwire.com/2015/06/11/hp-removes-memristors-fro... But what they watered it down to (and not delivered on that either) seems to be roughly equivalent to that fancy flash memory you can buy now for the new intel chipsets.
- cmiles74 8y ago
  It's unclear to me if the problem was a lack of vision on the part of HP or if the technology they came up with has fundamental problems that prevent it from being practical. Either one seems plausible.
  - jacobush 8y ago
    Don't know either. But if you google for something like - memristor oxygen transfer problem - lots of stuff comes up.
nabla9 8y ago
HP's lab (Stanley Williams) made their memristor announcement 10 years ago. "The missing memristor found" https://www.nature.com/articles/nature06932 https://www.nature.com/articles/nature06932 and still working on it "Capacitive neural network with neuro-transistors" https://www.nature.com/articles/s41467-018-05677-5 https://www.nature.com/articles/s41467-018-05677-5
cmiles74 8y ago
This article from Ars Technica talks a little bit about memristors and HP's plans for "The Machine". The original plan was for The Machine to demonstrate this technology, but HP ended up removing feature after feature (including memristor technology) before it's release. They quote John Sontag from HP in the article: "The simplest way to think about it is this—take a DRAM DIMM out, and put a memristor DIMM in,” said Sontag. “You now have another pool of memory that’s denser and nonvolatile. It’s a new class of memory—the consequence for operating systems is that moving stuff around from I/O devices [to and from disk] becomes unnecessary." https://arstechnica.com/information-technology/2014/06/hp-labs-machine-dissolves-the-difference-between-disk-and-memory/ https://arstechnica.com/information-technology/2014/06/hp-la...

leni536 8y ago

> A nonlinear ϕ-q curve will always have a positive, albeit variable slope. However, the ratio of ϕ to q still has the units of ohm, without a phase shift, making this a nonlinear resistor. I think this is false. A nonlinear ϕ-q curve will yield a resistance which depends on time in a manner that can't be described by a single nonlinear v-i curve.

contravariant 8y ago

I disagree with their claim that current is the time derivative of charge.

InitialLastName 8y ago
Are you being as pedantic as to ask for "through an area"? Because that's literally the defined relationship between current and charge.
- contravariant 8y ago
  This isn't mere pedantry, there is a difference between current and the time derivative of charge, I don't mind that they prefer to use one or the other, but if you insist on making a periodic table then you've got to take both into account. It's also an especially bad idea to claim the time derivative of current is the the double derivative of charge, given that these are two very different notions of derivative. To clarify, claiming current is the derivative of charge is like claiming the current of a river is the derivative of it's water level.
  - lnx01 8y ago
    Current is unequivocally the time derivative of charge. There're no two ways about it. i(t) = dQ(t) / dt "To clarify, claiming current is the derivative of charge is like claiming the current of a river is the derivative of it's water level." This statement is wrong, while water in some cases provides a decent analogy for electricity, this is not one of them.
    - contravariant 8y ago
      If I have a piece of wire with a constant current through it the charge everywhere on the wire remains constant. In fact the charge will be more or less neutral in most cases. Note that the alternative would be that the wire somehow accumulates charge as it passes current, which clearly isn't happening.

mchannon 8y ago

Fictional or no, this company sells them: https://knowm.org/memristors/ https://knowm.org/memristors/

deleted 8y ago
[deleted]
mfer 8y ago
You can buy them. Sometimes under branding that doesn't say memrister. You can learn how they work and the science (see the video on https://knowm.org/memristors/ https://knowm.org/memristors/) Are they a fundamental circuit element or one of the existing fundamental elements? We can let scientists debate that.
- VikingCoder 8y ago
  Yeah, I'm really lost. I feel like someone described useful properties of A Thing if it existed. Then we figured out how to make A Thing that had those useful properties. Is it A Thing, or Two Things? That's pedantic. Pragmatically, don't we have the useful properties?
  - cptaj 8y ago
    Don't be too quick to call academics pedantic. You're probably missing some key facts of the argument that make the distinction relevant.
    - mehrdadn 8y ago
      I agree with this. That said, the Wikipedia article has something interesting to point out regarding this [1]: > Martin Reynolds, an electrical engineering analyst with research outfit Gartner, commented that while HP was being sloppy in calling their device a memristor, critics were being pedantic in saying that it was not a memristor. [1] https://en.wikipedia.org/wiki/Memristor#Memristor_definition_and_criticism https://en.wikipedia.org/wiki/Memristor#Memristor_definition...
  - 8y ago

hatsunearu 8y ago

tldr + spoilers: there doesn't seem to be a mechanism for memristors to exist without significant nonlinearity or being a fully passive device, so it's kind of hard to say it's a fundamental circuit element

appleflaxen 8y ago

I went down the rabbit hole. Best terminal branches I found are: * HP created something they claimed was a memristor [1] * there were thermodynamic arguments about why it wouldn't work [2] * HP discontinued the architecture based on the component [3] 1. https://arstechnica.com/information-technology/2014/06/hp-labs-machine-dissolves-the-difference-between-disk-and-memory/ https://arstechnica.com/information-technology/2014/06/hp-la... 2. https://arxiv.org/ftp/arxiv/papers/1207/1207.7319.pdf https://arxiv.org/ftp/arxiv/papers/1207/1207.7319.pdf 3. https://www.theregister.co.uk/2016/11/29/hp_labs_delivered_machine_proof_of_concept_prototype_but_machine_product_is_no_more https://www.theregister.co.uk/2016/11/29/hp_labs_delivered_m...

no_identd 8y ago
Well... One thing about the OP paper smells very fishy to me: About two years ago, an extremely important result about Memristors and the notion of circuit elements in general came out. Unfortunately, it didn't get a lot of attention, and remains not-that-well-known even among experts. But: Anyone making claims like the OP paper would HAVE TO consider it in their model if they want to get taken serious. Here's the paper: https://hal.archives-ouvertes.fr/hal-01322396/document https://hal.archives-ouvertes.fr/hal-01322396/document Abdelouahab, Mohammed-Salah; Lozi, René; Chua, Leon O. - Memfractance: A Mathematical Paradigm for Circuit Elements with Memory [2016] The fact that the OP paper doesn't even mention Memfractance makes me highly suspicious, and doubly so as the OP paper also brings up a "periodic table" of circuit elements - something the Memfractance paper also does (embedded in ℝ²), but uh... let's say with a lot more behind it. In fact, I'll quote the entire "Conclusions" section of the Memfractance paper here: >In this paper, we have used fractional calculus in order to generalize and provide a mathematical frame for circuit elements with memory: memfractance. We have emphasized that the memfractance is a general paradigm for unifying and enlarging the family of memristive, memcapacitive and memin ductive elements. The motivation and significance of this paper is that there may exist future nano-electronics devices that are more realistically modeled with memfractance elements >We have generalized the definition of fractance which was first introduced in 1983, and after that, introduced the paradigm of memfractance which is fitted for circuit elements with memory such as memristor, meminductor, memcapacitor and second-order memristor first introduced here. We have defined a new element called memfractor which possesses interpolated characteristics between those four circuit elements. >We have then generalized Ohm’s law to memfractor and proved it. A particular, albeit wide-ranging, case of memfractance: the interpolated memfractance has been carefully studied through several numerical illustrative examples. Special attention has been devoted to the interpolated char- acteristic of a memfractor lying between memristor and memcapacitor which exhibits an unexpected new behavior of time variation of flux (φ–t curve). This phenomenon has been studied very carefully by the means of rigorous proofs. >Finally, following Chua’s recent work in which an infinite discrete family of circuit elements: the (α,β) element is introduced in the scope of developing a rigorous mathematical theory of nonlinear circuits, we extend the previous generalized Ohm’s law in order to embed memfractors elements into this periodic table. For this aim, we define an infinite continued family of circuit elements including circuit elements with memory (such as second-order memcapacitor and meminductor and third-order memristor), with a special metric. We call this family: fractional circuit element family. Note: That last passage is a reference to this specific paper: https://www.semanticscholar.org/paper/The-Fourth-Element-Chua/2d194f8216afbd5c9999b0931b9b75d47f923c51 https://www.semanticscholar.org/paper/The-Fourth-Element-Chu... - Chua, Leon O. - The Fourth Element [2012] Which the OP paper also doesn't cite. To me, this looks like a FUD campaign by Intel. I also briefly glanced over the OP paper besides checking for citations in it, and found this passage: "We have borrowed the expression “periodic table” as attributed to Chua" - which cites a secondary resource from 2008, before Chua's two above papers. Looking for any words starting with, or containing a fragment of, "fract" in the paper also yields no results. Looks like the typical outcome of someone who thinks they don't suck at literature research, but does suck at literature research, which, quite honestly, the vast majority of scientists do. Ask a randomly sampled researcher if they ever heard the term "Main path analysis" and they'll stare at you like a deer staring into headlights. Having said that: The paper does seem to bring up a few valid points, e.g. people making errors & drawing bad conclusions from mislabeled diagrams. This isn't an issue in Chua's work, however. Oh, and: Here, some slides on memfractance: http://slideplayer.com/slide/3869533/ http://slideplayer.com/slide/3869533/ Edit: Actually, this got generalized even further in early 2017: https://www.sciencedirect.com/science/article/pii/S1007570416301988 https://www.sciencedirect.com/science/article/pii/S100757041... Machado, J.Tenreiro; Galhano, Alexandra M. - Generalized two-port elements

DonHopkins 8y ago

My favorite fictional-sounding-but-real storage device is the Stringy Floppy! When I hung out at Radio Shack after school to play with the TRS-80's, some guy came by and showed his off, and I was in awe, and so jealous at how fast it was! I was sure that Stringy Floppies were the wave of the future. You didn't need to rewind them like tapes, because they wound back around!!! https://en.wikipedia.org/wiki/Exatron_Stringy_Floppy https://en.wikipedia.org/wiki/Exatron_Stringy_Floppy https://www.youtube.com/watch?v=EBfNy021K2Q https://www.youtube.com/watch?v=EBfNy021K2Q Then there was the Transputer! https://en.wikipedia.org/wiki/Transputer https://en.wikipedia.org/wiki/Transputer

rtkwe 8y ago
> You didn't need to rewind them like tapes, because they wound back around!!! You physically can't because they spool from the center like an 8-track tape. Probably why they didn't catch on rewinding lets you treat it more like a really slow hard drive.
aidenn0 8y ago
The Transputer is a success; a lot of the ideas developed for it are mainstream today, even if we don't call it a transputer. Kind of like all of the ideas from AI in the 70s and 80s that worked we don't call AI anymore.

jamesough 8y ago

Heard on grape vine that IBM claim to have pulled first silicon for a memristor RPU (design like below) just over a month ago. https://www.nature.com/articles/s41586-018-0180-5 https://www.nature.com/articles/s41586-018-0180-5

usernam33 8y ago

I dream of a bright Future where my PC will have no ram, hdd or ssd but only memristor memory. No need for booting or shutdown, I just add power and everything will be the same as it was when last used. Since I first read about them years ago this is still what I am waiting for even if it does not seem to be at grasp.

radarsat1 8y ago
Any reason this can't be done with flash? I wonder what the speed of a flash-RAM computer would be. I'm sure it'd be slow but it'd be interesting. You'd still have to dump and restore the CPU registers of course.
- mikepurvis 8y ago
  I think the main issues are that it would be crazy slow, and flash isn't really random access for write— you still have to blank whole pages at a time, so you'd definitely still want a RAM caching layer in front of the flash, even if it was being synced on a second by second basis. Plus the whole wear levelling thing would have a huge impact on lifespan. Tiny microcontrollers would be the first ones to benefit from an all-flash architecture, but they all still ship with both flash and RAM onboard.
  - dfox 8y ago
    NAND flash isn't random access even for reading, but generally these limitations are not inherent in the technology, but are motivated by reducing the die area per bit of storage (and thus cost). Purely random access "Flash" is typically called EEPROM and readily available with SRAM-compatible interface (and costs several times more than SRAM). In the microcontroller space there is for example TI's MSP430FR series which has unified non-volatile storage based on what could be described as core-memory on chip.
SamReidHughes 8y ago
You've got to be able to reboot for when program bugs leave your memory in an invalid state.

grillvogel 8y ago

more like memeristor

deleted 8y ago

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