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Cryptocurrency mining using integrated photonics
- tomhunters 5y agoThis is a great approach. You can see how they're going to change crypto mining through their interview Q&As. I'm just hoping that they will properly execute the plan.
- Mdubrov 5y agoYou can play with mining heavyhash (the underlying algorithm for photonic mining discussed in the story) on your cpu/gpu here https://pool.obtc.me/home https://pool.obtc.me/home
- OnlyRepliesToBS 5y agopls stop
- dvh 5y agoGreen light is 200nm, but we are already approaching 2nm with electronics, wouldn't that make any equivalent light CPU 100x larger/slower?
- automatic6131 5y agoThis has two false assumptions, one being that the process number (a marketing number chiefly), has any physical meaing. And another that you can compare it to the wave length of light. And also green light is 500-560nm.
- poulpy123 5y agoLarger, yes, slower no since it uses light as a transmission and not electrons
- e2le 5y agoWouldn't it be possible to run multiple concurrent processes on the same CPU using many different wavelengths of light?
- mmmBacon 5y agoWhy would shorter wavelength light make computation faster? Silicon is a great absorber below about 1000nm so infrared wavelengths are used. 200nm is ultraviolet.
- tromp 5y agooPoW FAQ from [1] 1. Is there reason to believe that the manufacturing of oPoW miners will be more decentralized than ASIC manufacturing currently? There are no guarantees in decentralized networks, but we think all evidence points to oPoW creating a more decentralized network. a. Cost of entering oPoW hardware manufacturing will be much lower due to Silicon Photonics using old CMOS nodes (~90 or 220 nm vs. ~7 nm for transistors). b. Removing electricity prices from the mining equation means that miners do not have to concentrate in regions with cheap power or depend on the sanction of governments that control most energy sources. 2. What other costs would replace energy? Hardware depreciation 3. Why create Heavy Hash, why not just compute SHA256 optically? This accomplishes the same goal without any changes to the Bitcoin codebase. Many have tried… there is a large economic incentive. Analog optical computing is limited in the types of computations it can do efficiently. It’s much more feasible to design the PoW around those limitations. 9. When will optical mining hardware be available? General-purpose photonic coprocessors are being commercialized by multiple companies that have shown interest in supporting mining hardware. Stay tuned for announcements. 10. Is the oPoW algorithm limited to optical devices? If not, will there be miners on the system using digital hardware? oPoW is reverse compatible with CPUs, GPUs, and ASICs. 11. Is oPoW less secure than SHA256? oPoW is based on Heavy Hash, a construction that includes SHA3 and inherits all of its security properties. (see Towards Optical Proof of Work above for a cryptographic analysis). [1] https://www.powx.org/opow https://www.powx.org/opow [2] HeavyHash: https://github.com/PoWx-Org/obtc-miner/tree/master/algo/heavyhash https://github.com/PoWx-Org/obtc-miner/tree/master/algo/heav...
- user-the-name 5y ago> 2. What other costs would replace energy? > Hardware depreciation In other words, instead of massive environmental damage through energy production, we would have massive environmental damage through e-waste.
- dr_dshiv 5y agoYeah, but maybe this drives the development of radically more efficient computing, a technology that compounds in value over time.
- Freskis 5y ago[deleted]
- neopba 5y agoThat's unfortunate. Just FYI here is a related story I posted some time ago https://news.ycombinator.com/item?id=27205918 https://news.ycombinator.com/item?id=27205918 Peace
- jazzyjackson 5y agoWhat's this about manufacturing photonic reservoir computers with old CMOS processes? We can do matrix multiplication with photon-buckets or what? Edit: I guess I'll read the paper for its intro to photonics, I haven't really heard of doing useful math with this stuff https://assets.pubpub.org/xi9h9rps/01581688887859.pdf https://assets.pubpub.org/xi9h9rps/01581688887859.pdf
- mmmBacon 5y agoOptical devices are physically large with waveguides about 1um and and most devices are a few hundred microns in size. The Mach Zehnders that they discuss are 100’s of microns in physical size. So it’s typical that silicon photonics are fabricated in older nodes in part because the resolution of advanced nodes is not needed and it’s a lot cheaper to use the older nodes. Additionally the sweet spot for silicon photonics is a wavelength ~ 1.3um (1.5um) so the node resolution is sufficient for the wavelength used.
- kybernetikos 5y agoPublic blockchain systems are distributed databases that anyone can submit write transactions to and where you don't need preauthorisation to join the system. In order to avoid the network being taken over by sybil attacks, it's necessary for participation to be based on locking up / committing / consuming something rare. Anything that becomes cheap or easy is not suitable for basing participation on. So far I know of systems using computational work (PoW), ownership of cryptocurrency (PoS), or storage space as that rare resource. The idea of using photonics to create a low energy 'proof of time' basis is interesting but there would still be difficult economic considerations. If acquiring the photonics is too hard, then you've got a centralised system, if it's too easy then the sybil resistance and environmental impact benefit goes away (because control of the system devolves into 'who can acquire the most hardware' incentivising massive production). Perhaps surprisingly, improving the cost efficiency of the work done by a traditional PoW blockchain doesn't reduce its energy usage, because the usage is determined by a competitive market place driven by supply & demand, not by a fixed amount of work needing to be done. Increasing the cost efficiency of the calculations just results in the blockchain doing more calculations. A huge chunk of the cost is in the electricity used, so power efficiency and cost efficiency are very very similar. Ultimately I don't think you can improve matters much by attacking power efficiency of the calculations. You may be able to move the economic balance point between upfront/ongoing costs by requiring more or more expensive hardware, but reducing ongoing electricity usage isn't a clear win if it's produced more waste and power usage during the creation and ultimate disposal of the hardware.
- danvayn 5y agoI think widespread institutional adoption of crypto is pretty important in this regard.Operating a photonic miner being hard provides more incentive to be a part of those 'mining' it, as you might expect. So, if it's beyond average user scope but within say .1-1% of a companies budget and could create massive dividends, why shouldn't they invest in this? It can be a little gross to consider, because no ones like idea of 'the rich getting richer', but that isn't really different from what happens today, anyways. What matters most is that the system has a lot of nodes to work with, and that can still happen here if there's enough adoption in this scenario. Not to mention that it should be hard to abuse your control in a public blockchain system. Governments could require companies to have an use photonic miner operating license and revoke it if they did something like this, for example. I think its a decent middle ground between centralized and decentralized. And (should?) produce less electric waste overall. I'm not sure, I don't really know much about photonics.
- jlokier 5y agoHeh. I worked on a type of photonic PoW in 2019 (but it wasn't silicon photonics). - It's faster and lower power for the hash rate. It's worth it. But not as fast and low power as hoped. - It's a great advantage for the early adopter who can mine that bit faster than everyone else for a short time. That was the motivation for the project. - Contrary to the title of the article, making hashing faster for less energy doesn't "help with the high energy consumption of the crypto currency mining activities" once the technology becomes available to enough miners. It's the same as the introduction of ASICs before it: only a temporary advantage to those few who have it first. Of course that's only a few miners, so it doesn't affect energy consumption of the whole blockchain much. As soon as a new technology becomes widespread enough to have a significant effect on the whole blockchain, blockchain proof-of-work returns to exactly the same amount of energy consumption as whatever technology came before it. It's because of how the mining-price system works, proof-of-work energy consumption is independent of the technology widely used. In other words, you can't solve the proof-of-work energy consumption problem with a new proof-of-work hashing technology. So whenever you see a headline or article promoting a new proof-of-work solution on the grounds that it will reduce energy consumption of the blockchain - that's false. Snake oil, even. (On the other hand, other mining methods such as proof-of-stake do reduce blockchain energy consumption for real, in exchange for different problems, perhaps.) But I think the Eindhoven people have understood this, and it's the journalism that misleads in this respect. From the article: > From our perspective, the ideal proof of work algorithm would be an algorithm that spends no energy, but time (i.e. pure delay). This kind of proof of work is hardly possible in the real world. So instead, we would love to see some sort of a “computational delay” when only a small fraction of energy is spent on proof-of-work computation, while this computation itself introduces a time-delay. We believe that photonics can help us to achieve such a “computational delay”. I'm surprised Verifiable Delay Functions (VDFs) are not mentioned. There is has been an emerging field of cryptography focused on delays enforced mathematically, called Verifiable Delay Functions, since about 2018. Rather like the technology race of proof-of-work, VDFs rely on the assumption that underlying technology (logic gates, arithmetic units (like in analogue photonics), etc) is somewhat evenly distributed; that nobody has access to a technology that can perform the calculations with much lower delay than everyone else. VDFs still won't reduce energy consumption if they are used as another form of proof-of-work. For example if running many delay functions calculated in parallel gives a mining advantage, many will be built and together they will use the same amount of energy as proof-of-work. To provide a real energy consumption benefit, the blockchain consensus method needs to change as well. Think "proof-of-verifiable-delay". As far as I know, no such method has been worked out yet.
- mistrial9 5y agoHNews people - multiple, lengthy comments here claim that "due to competitive pressures" the "total energy used to mine will be the same" no matter how hashes are calculated. The challenge problem in BTC is to find a number below a threshhold that fits a pattern. The threshhold changes in a two week regime. Finding the number is not prescribed, only the threshhold. Where is the required energy use here? Please illuminate
- pavlov 5y agoIf an invention enables hashes to be computed 10x more effectively, miners aren’t going to reduce their energy use by 90% — they’ll switch to the new equipment, increase their hash rate 10x, and keep using the available energy.
- tromp 5y agoThe difficulty D defines the expected number of double SHA256 hashes E[H] = 2^32 * D that must be computed on average per block to meet the difficulty target, which according to the average efficiency of mining ASICs implies an average amount of energy to be used.
- mistrial9 5y agofirst of all, difficulty D is a float, and there are no floats in the actual computation. Second, a float is not a number of hashes. bzzzzt edit- In plain English, this explanation is incorrect because it relies on floating point number D. Difficulty D is a convenience representation as float of the ratio of two very large integers; one of those large integers is the fixed MAX Target. The other vary large integer is varied by a prescribed formula, once every two weeks.
- api 5y agoOne of the limited upsides I see with the cryptocurrency bubble is that it's funded some progress in ASICs, and if it funded progress in photonics that would actually be quite awesome. Another upside is that it's funded a ton of very interesting cryptography research like SNARKs/STARKs and homomorphic encryption.
- mmmBacon 5y agoI see these things and while interesting they are just a lab curiosity. From the paper: By tuning the phase delays of each waveguide at each layer of the directional coupler mesh and the coupling region’s effective optical length using heaters it should be possible to achieve an arbitrary unitary transfer matrix As these phase sections are thermally tuned, they are slow and will have thermal crosstalk to their neighbors. While this is manageable it’s not exactly fast to create a new matrix transfer. Additionally, these devices drift over time and operating temperature. Changes over time are due to changes in local stress that cause refractive index to change. So this device as published has no ability to put the MZM bias into a known state and keep it there. Drift is a part of working with photonic devices and even when temperature controlled (very inefficient) they still need compensation. This compensation is the difference between a lab device and something that could be commercialized. Furthermore such devices have what we call parasitic reflections. When the phase is adjusted, the parasitic reflected phase is also adjusted creating an error in the output. For an analog computer that can only look at amplitude any numerical resolution would have to be coarser than the size of these parasitic reflections. This is just the tip of the iceberg. Yet none of these papers ever address these problems.