litchralee
@litchralee@sh.itjust.works
- Comment on Why aren't tall people also wider? 3 days ago:
From a biology perspective, it may not be totally advantageous to grow in all three dimensions at once. Certainly, as life forms become larger, they also require more energy to sustain, and also become harder to cool (at least for the warm blooded ones). Generally speaking, keeping cool is a matter of surface area (aka skin). But growing double in each of the three dimensions would be 4x more skin than before, but would be 8x more mass/muscle. That’s now harder to keep cool.
So growing needs to be done with intention: growing taller nets some survival benefits, such as having longer legs to run. Whereas growing wider or deeper doesn’t do very much.
But idk mang, I’m in a food coma from holiday dinner, just shooting from the hip lol
- Comment on Disconnect wire to close a switch with a simple circuit 5 days ago:
In any case, pending your reply, I would suggest the following circuit for reliable operation. This will require a P-channel MOSFET, which is different from the two MOSFETs you tried earlier, which are all N-channel. This will also use two resistors. I am making an assumption that your speaker module simply requires two wires at feed it 4 volts, and does not care whether we add a switching circuit to either wire, the positive or negative wire.
This type of circuit would be described as an inverting, low-side MOSFET switching circuit. The inverting part means that when the MOSFET is fed a lower voltage, that causes the transistor to become active, whereas a non-inverting circuit would require feeding the MOSFET with a higher voltage to make the transistor become active.
Low-side switching refers to the fact that the load (ie the speaker module) is permanently attached to the higher voltage (the high-side) and we are manipulating the low-side. Not all electronic loads can be used with low-side switching, but this is the easiest mode to implement using a single MOSFET transistor. As a general rule, to do low-side switching always requires a P-channel MOSFET.
As for why we cannot do high-side switching (which would use an N-channel MOSFET), it is because a typical N-channel MOSFET requires that the gate be a few volts higher than the source. But consider that when the transistor turns on, the drain and source become almost-similar voltages. So if the drain is attached to 4 volts, and as the transistor becomes active, the source rises to something like 3.95 volts, then what gate do we use to keep the transistor active? If we give 4v to the train, then the gate-to-source voltage is only 0.05 volts, which is insufficient to keep the transistor on. We would need an external source to provide more gate voltage, relative to the source pin. If we tried such a high-side switching circuit anyway, it would quickly oscillate: the transistor tries to turn on, then turns itself off, then back on, and so forth.
The way that my suggested circuit works is as follows: when the tripwire (marked as SW3) is in place, then R4 and R2 will form a voltage divider. Given that the battery supplies 4v, we can show that the voltage at the MOSFET’s gate will be 91% of 4v, or 3.64 volts. This should be just enough to prevent the P-channel MOSFET from becoming active. Note: a P-channel MOSFET becomes active when there is a low gate-to-drain voltage, with 0v causing the transistor to become active. In this way, with the trip-wire, the transistor will not allow current to pass through the speaker.
When the tripwire is pulled out, this breaks the connection to R4. That leaves the gate connected to only R2, which is connected to the negative side of the battery. Thus, any charge in the gate will seep away through R2, meaning that the voltage across R2 will equalize at 0v. This means the gate-to-drain voltage will be 0v, which means the MOSFET will activate. And that allows current to power the speaker module.
Note: one end of the tripwire (labeled #1 in the diagram) will still have 4v on it. If the tripwire is cleanly detached from the whole circuit, using your loop-of-wire and nails idea, then there is no problem. But if the tripwire is still hanging onto the 4v side of the circuit, then be careful that the tripwire doesn’t make contact with another part of this circuit. The R4 resistor will still be there, so there won’t be a short circuit or anything bad like that. But if that tripwire reconnects to the gate, then the transistor will deactivate again, stopping the music.
I wish you good luck in this endeavor!
- Comment on Disconnect wire to close a switch with a simple circuit 5 days ago:
I’m going to try to answer your situation, but although time appears to be of the essence, I need to first understand exactly what you’ve already tried. So bear with me for a moment.
The examples I found were very simple, involving an NPN transistor (2n2222), 10KΩ resistor, battery, and DC Piezo speaker.
With my initial attempt, I wired +4V from the switch to the transistor’s collector and then separated the collector from the base with a resistor. I connected the emitter to the pin that, when the switch is engaged, would send 4V through and power the module.
Does this diagram correctly describe what you tried as a first attempt?
schematic diagram of attempt 1
Someone suggested that what I actually needed was a MOSFET …
I have the resistor connected between Gate and Drain, +4V going to drain, and the load from the module on Source.
With an RFP30N06LE, I get about 2V output to Source. With an IRF840N, I’m only getting 0.9V.
Do these diagrams match your circuits with each MOSFET?
schematic diagram of attempt 2
schematic diagram of attempt 3
What I am not able to understand, in your last photo with the MOSFET, is where the blue wire is going.
- Comment on Why do personal knowledge base applications like Obsidian have all these bells and whistles for querying and parsing metadata/frontmatter but nothing similar for the actual content of notes? 6 days ago:
I recently learned about Obsidian from a friend, but haven’t started using it yet, so perhaps I can offer a perspective that differs from current users of Obsidian or any of the other apps you listed.
To start, I currently keep a hodge-podge of personal notes, some digitally and some in handwriting, covering different topics, using different formats, and there’s not really much that is common between any of these, except that I am the author. For example, I keep a financial diary, where I intermittently document the thinking behind certain medium/long-term financial decisions, which are retained only as PDFs. I also keep README.md files for each of the code repos that I have for electronics and Kubernetes-related projects. Some of my legacy notes are in plain-text .txt file format, where I’m free-form record what I’ve working on, relevant links, and lists of items outstanding or that are TODOs. And then there is the handwritten TODO and receivables list that I keep on my fridge.
Amongst all of this chaos, what I would really like to have the most is the ability to organize each “entry” in each of their respective domains, and then cross-reference them. That is, I’m not looking to perform processing on this data, but I need to organize this data so that it is more easily referenced. For example, if I outline a plan to buy myself a new server to last 10 years, then that’s a financial diary entry, but it would also manifest itself with TODO list items like “search for cheap DDR5 DIMMs” (heaven help me) and “find 10 GbE NIC in pile”. It may also spawn an entry in my infrastructure-as-code repo for my network, because I track my home network router and switch configurations in Git and will need to add new addresses for this server. What I really need is to be able to refer to each of these separate documents, not unlike how DOIs uniquely identify research papers in academic journals.
It is precisely because my notes are near-totally unstructured and disparate that I want a powerful organization system to help sort it, even if it cannot process or ingest those notes. I look at Obsidian – based on what little I know of it – like a “super filing cabinet” – or maybe even a “card catalog” but that might be too old of a concept lol – or like a librarian. After all, one asks the librarian for help finding some sort of book or novel. One does not ask the librarian to rehash or summarize or extract quotes from those books; that’s on me.
- Comment on How long until we can start shorting years to 2 numbers again? 6 days ago:
In the English-speaking world, you can always shorten the year from 4 to 2 digits. But whether: 1) this causes confusion or 2) do you/anyone care if it does, are the points of contention. The first is context-dependent: if a customer service agent over the phone is trying to confirm your date of birth, there’s no real security issue if you only say the 2 digit year, because other info would have to match as well.
If instead you are presenting ID as proof of age to buy alcohol, there’s a massive difference between 2010 and 1910. An ID card and equivalent documentation must use a four digit year, when there is no other available indicator of the century.
For casual use, like signing your name and date on a holiday card, the ambiguity of the century is basically negligible, since a card like that is enjoyed at the time that it’s read, and isn’t typically stashed away as a 100-year old memento.
That said, I personally find that in spoken and written English, the inconvenience of the 4 digit year is outweighed by the benefit of properly communicating with non-American English users. This is because us American speak and write the date in a non-intuitive fashion, which is an avoidable point of confusion.
Typical Americans might write “7/1/25” and say “July first, twenty five”. British folks might read that as 7 January, or (incorrectly) 25 January 2007. But then for the special holiday of “7/4/25”, Americans optionally might say “fourth of July, twenty five”. This is slightly less confusing, but a plausible mishearing by the British would be “before July 25”, which is just wrong.
The confusion is minimized by a full 4 digit year, which would leave only the whole day/month ordering that is ambiguous. That is, “7/1/2025”.
Though I personally prefer RFC3339 dates, which are strictly YYYY-mm-dd, using 4 digit years, 2 digit months, and 2 digit days. This is always unambiguous, and I sign all paperwork like this, unless it explicitly wants a specific format for the date.
- Comment on If you had too, how would go about running a Instagram account? 6 days ago:
For the objective of posting photos to an Instagram account while preserving as much privacy as possible, your approach of a separate machine and uploading using its web browser should be sufficient. That said, Instagram for web could also be sandboxed using a private browsing tab on your existing desktop. Certainly, avoiding an installed app – such as the mobile app – will prevent the most obtuse forms of espionage/tracking.
That said, your titular question was about how to maintain an Instagram account, not just post images. And I would say that as a social media platform, this would include engagement with other accounts and with comments. For that objective, having a separate machine is more unwieldy. But even using a private browsing tab on your existing machine is still subject to the limits that Instagram intentionally imposes on their desktop app: they save all the crucial value-add features for the mobile app, where their privacy invasion is greatest.
To use Instagram in the least obtuse manner means to play the game by their rules, which isn’t really compatible with privacy preservation. To that end, if you did want a full Instagram experience, I would suggest getting a separate, cheap mobile phone (aka a “YOLO phone”) to dedicate to this task. If IG doesn’t need a mobile number, then you won’t even need a working SIM account. Then load your intended images using USB file transfer, and use an app like Imagepipe (available on F-Droid) to strip image metadata.
- Comment on [deleted] 1 week ago:
For the blockchain technology at the very core foundation of cryptocurrencies, it’s a reasonable concept that solves a specific challenge (ie no one can change this value unless they have the cryptographic key) and the notion of an indelible or tamper-evident ledger is useful in other fields (eg certificate revocation lists). Using a blockchain as a component is – like all of engineering – about picking the right tool for the job, so I wouldn’t say that having/not having a block chain imparts any sort of opinionation or qualities of good/bad.
One step above the base technology is the actual application as currency, meaning a representation of economic value, either to store that value (eg gold) or for active trade (eg the €2 Euro coin). All systems of currency require: 1) recognition and general consensus as to their value, and 2) fungibility (ie this $1 note is no different than your $1 note), and 3) the ability to functionally transfer the currency.
Against that criteria, cryptocurrencies have questionable value, as seen by how volatile the cryptocurrency-to-fiat currency markets are. Observe that the USD or Euro or RMB are used for people’s salaries, denominate their home mortgage loans, for buying and selling crude oil, and so on. Yet basically no one uses cryptocurrency for those tasks, no one writes or accepts business-to-business contracts denominated in cryptocurrency, and only a small handful of sovereign states accept cryptocurrency as valid payment. That’s… not a great outlook for circulating the currency.
But for fungibility, cryptocurrency clearly meets that test, and probably exceeds the fiat currencies: there’s no such thing as a “torn” Bitcoin note. There are no forgeries of Etherium. It is demonstrable that a unit of cryptocurrency that came from blood-diamond profits is indistinguishable from a unit that was afforded by wages at a fuel station in Kentucky. There are no “marked notes” or “ink packs” when committing cryptocurrency theft, and it’s relatively easy to launder cryptocurrency through thousands of shell accounts/addresses. To launder physical money a thousand times is physically impossible, and is way too suspicious for digitalized fiat current transfers.
And that brings us to the ability to actually transfer cryptocurrency. While it’s true that it should only be an extra ledger entry to move funds from one address/account to another, each system has costs buried somewhere. Bitcoin users have to pay the transaction costs, or currencies pegged to other currencies have to “execute” a “smart contract”, with attendant verification costs such as proof-of-work or proof-of-stake. These costs simply don’t exist when I hand a $20 note to a fuel station clerk. Or when my employer sends my wages via ACH electronic payment.
Observe how cryptocurrency is traded not at shops with goods (eg Walmart) or shops for currency (eg bureau de change at the airport) but mostly only through specialized ATMs or through online exchange websites. The few people who genuinely do use their cryptocurrency wallets to engage transactions are now well in the minority, overshadowed by scammers, confidence/romance tricksters, investment funds with no idea of what they’re doing except to try riding the bandwagon, and individuals who have never traded financial instruments but were convinced by “their buddy’s friend” who said cryptocurrency was a money-making machine.
To that end, I would say that cryptocurrencies have brought out the worst of financial manipulators, and their allure is creating serious financial perils for everyday people, whether directly as a not-casino casino or to pay a ransomware extortion, or indirectly through the destabilization of the financial system. No one is immune to a breakdown of the financial system, as we all saw in 2008.
I used to like discussing eith people about the technical merits of ledger-based systems, but with the awful repercussions of what they’ve enabled, it’s a struggle to have a coherent conversation without someone suggesting a cryptocurrency use-case. And so I kinda have to throw the whole baby out with the bathwater. Maybe when things quiet down in a few decades, the technology can be revisited from a sober perspective.
- Comment on Finally implemented PGP in Jotty <3 1 week ago:
If I understand the Encryption Markdown page, it appears the public/private key are primarily to protect the data at-rest? But then both keys are stored on the server, although protected by the passphrase for the keys.
So if the protection boils down to the passphrase, what is the point of having the user upload their own keypair? Are the notes ever exported from the instance while still being encrypted by the user’s keypair?
Also, why PGP? PGP may be readily available, but it’s definitely not an example of user-friendliness, as exemplified by its lack of broad acceptance by non-tech users or non-government users.
And then, why RSA? Or are other key algorithms supported as well, like ed25519?
- Comment on Does each country have a book/library of the laws of the land that a commoner can consult to check if they're about to do something illegal? 1 week ago:
Directly answering the question: no, not every country has such a consolidated library that enumerates all the laws of that country. And for reasons, I suspect no such library could ever exist in any real-life country.
I do like this question, and it warrants further discussion about laws (and rules, and norms), how they’re enacted and enforced, and how different jurisdictions apply the procedural machine that is their body of law.
To start, I will be writing from a California/USA perspective, with side-quests into general Anglo-American concepts. That said, the continental European system of civil law also provides good contrast for how similar yet different the “law” can be. Going further abroad will yield even more distinctions, but I only have so much space in a Lemmy comment.
The first question to examine is: what is the point of having laws? Some valid (and often overlapping) answers:
- Laws describe what is/isn’t acceptable to a society, reflecting its moral ideals
- Laws incentivize or punish certain activities, in pursuit of public policy
- Laws set the terms for how individuals interact with each other, whether in trade or in personal life
- Laws establish a procedure machine, so that by turning the crank, the same answer will output consistently
From these various intentions, we might be inclined to think that “the law” should be some sort of all-encompassing tome that necessarily specifies all aspects of human life, not unlike an ISO standard. But that is only one possible way to meet the goals of “the law”. If instead, we had a book of “principles” and those principles were the law, then applying those principles to scenarios would yield similar result. That said, exactly how a principle like “do no harm” is applied to “whether pineapple belongs on pizza” is not as clear-cut as one might want “the law” to be. Indeed, it is precisely the intersection of all these objectives for “the law” that makes it so complicated. And that’s even before we look at unwritten laws.
The next question would be: are all laws written down? In the 21st Century, in most jurisdictions, the grand majority of new laws are recorded as written statutes. But just because it’s written down doesn’t mean it’s very specific. This is the same issue from earlier with having “principles” as law: what exactly does the USA Constitution’s First Amendment mean by “respecting an establishment of religion”, to use an example. But by not micromanaging every single detail of daily life, a document that starts with principles and is then refined by statute law, that’s going to be a lot more flexible over the centuries. For better/worse, the USA Constitution encodes mostly principles and some hard rules, but otherwise leaves a lot of details left for Congress to fill in.
Flexibility is sometimes a benefit for a system of law, although it also opens the door for abuse. For example, I recall a case from the UK many years ago, where crown prosecutors in London had a tough time finding which laws could be used to prosecute a cyclist that injured a pedestrian. As it turned out, because of the way that vehicular laws were passed in the 20th Century, all the laws on “road injuries” basically required the use of an automobile, and so that meant there was a hole in the law, when it came to charging bicyclists. They ended up charging the cyclist with the criminal offense of “furious driving”, which dated back to an 1860s statute, which criminalized operating on the public road with “fury” (aka intense anger).
One could say that the law was abused, because such an old statute shouldn’t be used to apply to modern-day circumstances. That said, the bicycle was invented in the 1820s or 1830s. But one could also say that having a catch-all law is important to make sure the law doesn’t have any holes.
Returning to American law, it’s important to note that when there is non-specific law, it is up to the legislative body to fill those gaps. But for the same flexibility reasons, Congress or the state or tribal legislatures might want to confer some flexibility on how certain laws are applied. They can imbue “discretion” upon an agency (eg USA Department of Commerce) or to a court (eg Superior Court of California). At other times, they write the law so that “good judgement” must be exercised.
As those terms are used, discretion more-or-less means having a free choice, where either is acceptable but try to keep within reasonable guidelines. Whereas “good judgement” means the guidelines are enforced and there’s much less wiggle-room for arbitraryness. And confusingly so, sometimes there’s both a component of discretion and judgment, which usually means Congress really didn’t know what else to write.
Some examples: a District Attorney anywhere in California has discretion when it comes to filing criminal charges. They could outright choose to not prosecute person A for bank robbery, but proceed with prosecuting person B for bank robbery, even though they were working together on the same robbery. As an elected official, the DA is supposed to weigh the prospects of actually obtaining a guilty verdict, as well as whether such prosecution would be beneficial to the public or a good use of the DA office’s limited time and budget. Is it a bad look when a DA prosecutes one person but not another? Yes. Are there any guardrails? Yes: a DA cannot abuse their discretion by considering disallowed factors, such as a person’s race or other immutable characteristics. But otherwise, the DA has broad discretion, and ultimately it’s the voters that hold the DA to account.
Another example: the USA Environmental Protection Agency’s Administrator is authorized by the federal Clean Air Act to grant a waiver of the supremacy of federal automobile emissions laws, to the state of California. That is to say, federal law on automobile emissions is normally the law of the land and no US State is allowed to write their own laws on automobile emissions. However, because of the smog crisis in the 70/80s, the feds considered that California was a special basket-case and thus needed their own specific laws that were more stringent than federal emissions laws. Thus, California would need to seek a waiver from the EPA to write these more stringent laws, because the blanket rule was “no state can write such laws”. The federal Clean Air Act explicitly says only California can have this waiver, and it must be renewed regularly by the EPA, and that California cannot dip below the federal standards. The final requirement is that the EPA Administrator shall issue the waiver if California requests it, and if they qualify for it.
This means the EPA Administrator does not have discretion, but rather is exercising good judgement: does California’s waiver application satisfy the requirements outlined in the Clean Air Act? If so, the Administrator must issue the waiver. There is no allowance of an “i don’t wanna” reason for non-issuance of the waiver. The Administrator could only refuse if they show that California is somehow trying to do an end-run around the EPA, such as by trying to reduce the standards.
The third question is: do laws encompass all aspects of everything?. No, laws are only what is legally enforced. There are also rules/by-laws and norms. A rule or by-law is often something enforced by something outside the legal system’s purview. For example, the penalty for violating a by-law of the homeowner’s association might be a revocation of access to the common spaces. For a DnD group, the ultimate penalty for violating a rule might be expulsion.
Meanwhile, there are norms which are things that people generally agree on, but felt were so commonplace that breaking the norm would make everything else nonfunctional. For example, there’s a norm that one does not use all-caps lock when writing an online comment, except to represent emphasis or yelling. One could violate that norm with no real repercussions, but everyone else would dislike you for it, they might not want to engage further with you, they might not give you any benefit of the doubt, they may make adverse inferences about you IRL, or other things.
TL;DR: there are unwritten principles that form part of the law, and there’s no way to record all the different non-law rules and social norms that might apply to any particular situation.
- Comment on is it normal for smart thermostat to rotate very often for no appearant reason? 2 weeks ago:
Please explain what you mean by “rotate”. The thermostat is physically turning in-place, as though a wall clock?
- Comment on Password managers... 2 weeks ago:
For a single password, it is indeed illogical to distribute it to others, in order to prevent it from being stolen and misused.
That said, the concept of distributing authority amongst others is quite sound. Instead of each owner having the whole secret, they only have a portion of it, and a majority of owners need to agree in order to combine their parts and use the secret. Rather than passwords, it’s typically used for cryptographically signing off on someone’s authenticity, where it’s known as threshold signatures
Imagine for a moment, instead of having 1 secret key, you have 7 secret keys, of which 4 are required to cooperate in the FROST protocol to produce a signature for a given message. You can replace these numbers with some integer t (instead of 4) out of n (instead of 7).
This signature is valid for a single public key.
If fewer than t participants are dishonest, the entire protocol is secure.
- Comment on How does the private equity bubble compare to the AI bubble if at all? 2 weeks ago:
Used for AI, I agree that a faraway, loud, energy-hungry data center comes with a huge host of negatives for the locals, to the point that I’m not sure why they keep getting building approval.
But my point is that in an eventual post-bubble puncture world where AI has its market correction, there will be at least some salvage value in a building that already has power and data connections. A loud, energy-hungry data center can be tamed to be quiet and energy-sipping based on what’s hardware it’s filled in. Remove the GPUs and add some plain servers and that’s a run-of-the-mill data center, the likes of which have been neighbors to urbanites for decades.
I suppose I’d rehash my opinion as such: building new data centers can be wasteful, but I think changing out the workload can do a lot to reduce the impacts (aka harm reduction), making it less like reopening a landfill, and more like rededicating a warehouse. If the building is already standing, there’s no point in tearing it down without cause. Worst case, it becomes climate-controlled paper document storage, which is the least impactful use-case I can imagine.
- Comment on How does the private equity bubble compare to the AI bubble if at all? 2 weeks ago:
Racks/cabinets, fiber optic cables, PDUs, CAT6 (OOBM network), top-of-rack switches, aggregation switches, core switches, core routers, external multi-homed ISP/transit connectivity, megawatt three-phase power feeds from the electric utility, internal power distribution and step-down transformers, physical security and alarm systems, badge access, high-strength raised floor, plenum spaces for hot/cold aisles, massive chiller units.
- Comment on How does the private equity bubble compare to the AI bubble if at all? 2 weeks ago:
Absolutely, yes. I didn’t want to elongate my comment further, but one odd benefit of the Dot Com bubble collapsing was all of the dark fibre optic cable laid in the ground. Those would later be lit up, to provide additional bandwidth or private circuits, and some even became fibre to the home, since some municipalities ended up owning the fibre network.
In a strange twist, the company that produced a lot of this fibre optic cable and went bankrupt during the bubble pop – Corning Glass – would later become instrumental in another boom, because their glass expertise meant they knew how to produce durable smartphone screens. They are the maker of Gorilla Glass.
- Comment on How does the private equity bubble compare to the AI bubble if at all? 2 weeks ago:
I’m not going to come running to the defense of private equity (PE) firms, but compared to so-called AI companies, the PE firms are at least building tangible things that have an ostensible alternative use. A physical data center building – even one located far away from the typical metropolitan area that have better connectivity to the world’s fibre networks – will still be an asset with some utility, when/if the AI bubble pops.
In that scenario, the PE firm would certainly take a haircut on their investment, but they’d still get something because an already-built data center will sell for some non-zero price, with possible buyers being the conventional, non-AI companies that just happen to need some cheap rack space. Looking at the AI companies though, what assets do they have which carry some intrinsic value?
It is often said that during the California Gold Rush, the richest people were not those which staked our the best gold mines, but those who sold pickaxes to miners. So too would PE firms pivot to whatever comes next, selling their remaining interest from the prior hype cycle and moving to the next.
I’ve opined before that because no one knows when the bubble with burst, it is simultaneously financially dangerous to: 1) invest into that market segment, but also 2) to exit from that market segment. And so if a PE firm is already bet most of the farm, then they might just have to follow through with it and pray for the best.
- Comment on Do we have enough supra conductor to support quantum computing growth? 2 weeks ago:
I presume we’re talking about superconductors; I don’t know what a supra (?) conductor would be.
There are two questions here: 1) how much superconducting materials are required for today’s state-of-the-art quantum computers , and 2) how quantum computers would be commercialized. The first deals in material science and whether more-capable superconductors can be developed at scale, ideally for room-temperature and thus wouldn’t require liquid helium. Even a plentiful superconductor that merely requires merely liquid nitrogen would he a bit improvement.
But the second question is probably the limiting factor, because although quantum computers are billed as the next iteration of computing, the fact of the matter is that “classical” computers will still be able to do most workloads faster than quantum computers, today and well into the future.
The reality is that quantum computers excel at only a specific subset of computational tasks, which classically might require mass parallelism. For example, breaking encryption algorithms is one such task, but even applying Shoe’s Algorithm optimally, the speed-up is a square-root factor. That is to say, if a cryptographic algorithm would need 2^128 operations to brute-force on a classical computer, then an optimal quantum computer would only need 2^64 quantum operation. If quantum computers achieve the equivalent performance of today’s classical computers, then 2^64 is achievable, so that cryptographic algorithm is broken.
If. And it’s kinda easy to see how to avoid this problem: use “bigger” cryptographic algorithms. So what would quantum computers be commercialized for? Quite frankly, I have no idea: until such commonly-available quantum computers are available, and there is a workload which classical computers cannot reasonably do, then there won’t be a marker for quantum computers.
If I had to guess, I imagine that graph theorists will like quantum computers, because graphs can increase in complexity really fast on classical machines, but is more tame on quantum computers. But the only commercial applications from that would be for social media (eg Facebook hires a lot of graph theorists) and surveillance (finding correlations in masses of data). Uh, those are not wide markets, although they would have deep pockets to pay for experimental quantum computers.
So uh, not much that would benefit the average person.
- Comment on Fun/interesting things to self host? 2 weeks ago:
Weather station, terrestrial/satellite TV DVR (TVHeadend), Git repository (Forgejo for a nice web UI, cgit for a classic UI), DNS resolver.
- Comment on If your federal government cut internet access to your whole town then where in your town would you think that "the people" would get together to protest ? 2 weeks ago:
If the town is Bielefeld in Germany, then at the Old Market square. But that city doesn’t exist.
- Comment on Why don't compasses have just two Cardinal directions (North, East, -North, -East)? 3 weeks ago:
I see my typo, and it’s too funny and I’m just going to roll with it haha
- Comment on Why don't compasses have just two Cardinal directions (North, East, -North, -East)? 3 weeks ago:
As a practical matter, relative directions are already hard enough, where I might say that Colorado is east of California, and California is west of Colorado.
To use +/- East would mean there’s now just a single symbol difference between relative directions. California bring -East of Folorado, and Colorado being +East of California.
Also, we need not forget that the conventional meridian used for Earth navigation is centered on Greenwich in the UK, and is a holdover from the colonial era where Europe is put front-and-center on a map and everything else is “free real estate”. Perhaps if the New World didn’t exist, we would have right-ascension based system where Greenwich is still 0-deg East and Asia is almost 160-deg East. Why would colonialists center the maps on anywhere but themselves?
- Comment on Are people with High functioning autism allowed to become police officers? 3 weeks ago:
Assuming this is in the USA, I want to note that there are many other available jobs in the protective services occupation, that can be public or private sector, that face the general public (or not), and that don’t have any particular positive or negative connotation attached to the job, even after hours.
The Bureau of Labor Statistics (BLS) has a fantastic reference for available occupations:
- Comment on What's the best way to answer someone who accuses you of being a bot because they don't like what you have to say? 3 weeks ago:
Block, ignore, and continue living your non-bot life.
- Comment on Who shops at small businesses? 3 weeks ago:
Restaurants (including franchises of chains) are indeed a major segment of small businesses. Looking more broadly, any industry which: 1) offers a service/product/utility, and 2) has proven to not have a tendency to inflate beyond its fundamental target audience, those are likely to be small businesses. Those are the parameters which stave off any sort of corporate takeovers and consolidations, because they won’t invest in a small business if the prospect of infinite growth isn’t there. So the business stays small. And small is often perfectly fine.
That is to say, restaurants (humans can only eat so much food), bicycle stores (humans can only ride so much per day), and local produce shops (even in the Central Valley of California, there’s only so much produce to sell, and humans can’t eat infinite quantities) have these qualities.
But compare those to a restaurant supply warehouse or music equipment store, since those items can be shipped and need no customization by the end user. Consolidation and corporate meddling is possible and probable.
Then you have industries which are often local and small but are prone to financial hazards, such as real estate agents and used car lenders. Because they get paid as a percentage of the transaction size, if the price of houses or cars go up in an unchecked fashion, the profit margins also increase linearly, which makes them more tempting for corporate involvement.
There are corporate-owned national chains of real estate agents, self storage, department stores, and payday loan offices. But I’m not aware of a national chain for bicycle or bicycle accessories. Even regional chains for bicycles are few and far between. Some consolidation has happened there, but by most definitions, a bicycle shop is very much a small business.
- Comment on Are there any VPNs that support dedicated IPv6 addresses? 3 weeks ago:
- Comment on Are there any VPNs that support dedicated IPv6 addresses? 3 weeks ago:
You might also try asking on !ipv6@lemmy.world .
Be advised that even if a VPN offers IPv6, they may not necessarily offer it sensibly. For example, some might only give you a single address (aka a routed /128). That might work for basic web fetching but it’s wholly inadequate if you wanted the VPN to also give addresses to any VMs. And that’s a fair ask, because a normal v6 network can usually do that, even though a typical Legacy IP network can’t.
Some VPNs will offer you a /64 subnet, but their software won’t check if your SLAAC-assigned address is leaking your physical MAC address. Your OS should have privacy-extensions enabled to prevent this, but good VPN software should explicitly check for that. Not all software does.
- Comment on Conntrack question 4 weeks ago:
Connection tracking might not be totally necessary for a reverse proxy mode, but it’s worth discussing what happens if connection tracking is disabled or if the known-connections table runs out of room. For a well-behaved protocol like HTTP(S) that has a fixed inbound port (eg 80 or 443) and uses TCP, tracking a connection means being aware of the TCP connection state, which the destination OS already has to do. But since a reverse proxy terminates a TCP connection, then the effort for connection tracking is minimal.
For a poorly-behaved protocol like FTP – which receives initial packets in a fixed inbound port but then spawns a separate port for outbound packers – the effort of connection tracking means setting up the firewall to allow ongoing (ie established) traffic to pass in.
But these are the happy cases. In the event of a network issue that affects an HTTP payload sent from your reverse proxy toward the requesting client, a mid-way router will send back to your machine an ICMP packet describing the problem. If your firewall is not configured to let all ICMP packets through, then the only way in would be if conntrack looks up the connection details from its table and allows the ICMP packet in, as “related” traffic. This is not dissimilar to the FTP case above, but rather than a different port number, it’s an entirely different protocol.
And then there’s UDP tracking, which is relevant to QUIC. For hosting a service, UDP is connectionless and so for any inbound packet we received on port XYZ, conntrack will permit an outbound packet on port XYZ. But that’s redundant since we presumably had to explicitly allow inbound port XYZ to expose the service. But in the opposite case, where we want to access UDP resources on the network, then an outbound packet to port ABC means conntrack will keep an entry to permit an inbound packet on port ABC. If you are doing lots of DNS lookups (typically using UDP), then that alone could swamp the con track table: kb.isc.org/docs/aa-01183
It may behoove you to first look at what’s filling conntrack’s table, before looking to disable it outright. It may be possible to specifically skip connection tracking for anything already explicitly permitted through the firewall (eg 80/443). Or if the issue is due to numerous DNS resolution requests from trying to look up spam sources IPs, then perhaps either the logs should not do a synchronous DNS lookup, or you can also skip connection tracking for DNS.
- Comment on GPU prices are coming to earth just as RAM costs shoot into the stratosphere - Ars Technica 4 weeks ago:
Oh, it’s a user space (FUSE) driver. I was rather hoping it was an out-of-tree Linux kernel driver, since using FUSE will: 1) always pass back to userspace, which costs performance, and 2) destroys any possibility of DMA-enabled memory operations (DPDK is a possible exception). I suppose if the only objective was to store files in VRAM, this does technically meet that, but it’s leaving quite a lot on the table, IMO.
If this were a kernel module, the filesystem performance would presumably improve, limited by how the VRAM is exposed by OpenCL (ie very fast if it’s just all mapped into PCIe). And if it was basically offering VRAM as PCIe memory, then this potentially means the VRAM can be used for certain RAM niche cases, like hugepages: some applications need large quantities of memory, plus a guarantee that it won’t be evicted from RAM, and whose physical addresses can be resolved from userspace (eg DPDK, high-performance compute). If such a driver could offer special hugepages which are backed by VRAM, then those application could benefit.
And at that point, on systems where the PCIe address space is unified with the system address space (eg x86), then it’s entirely plausible to use VRAM as if it were hot-insertable memory, because both RAM and VRAM would occupy known regions within the system memory address space, and the existing MMU would control which processes can access what parts of PCIe-mapped-VRAM.
Is it worth re-engineering the Linux kernel memory subsystem to support RAM over PCIe? Uh, who knows. Though I’ve always like the thought of DDR on PCIe cards. All technologies are doomed to reinvent PCIe, I think, said someone from Level1Techs.
- Comment on GPU prices are coming to earth just as RAM costs shoot into the stratosphere - Ars Technica 4 weeks ago:
Ok, I have to know: how is this done, and what do people use it for?
- Comment on Is there a word for when someone is not capable of, or doesn't try to understand verbal communication in a language, they are fluent in similar to functionally illiterate but for speech? 4 weeks ago:
It might not be used frequently, but perhaps “incomprehension”?
- Comment on Is there a practical reason data centers have to sprawl outward instead of upward? 5 weeks ago:
In the past, we did have a need for purpose-built skyscrapers meant to house dense racks of electronic machines, but it wasn’t for data centers. No, it was for telephone equipment. See the AT&T Long Lines building in NYC, a windowless monolith of a structure on Lower Manhattan. It stands at 170 meters (550 ft).
This NYC example shows that it’s entirely possible for telephone equipment to build up, and was very necessary considering the cost of real estate in that city. But if we look at the difference between a telephone exchange and a data center, we quickly realize why the latter can’t practically achieve skyscraper heights.
Data centers consume enormous amounts of electric power, and this produces a near-equivalent amount of heat. The chiller units for a data center are themselves estimated to consume something around a quarter of the site’s power consumption, to dissipate the heat energy of the computing equipment. For a data center that’s a few stories tall, the heat density per land area is enough that a roof-top chiller can cool it. But if the data center grows taller, it has a lower ratio of rooftop to interior volume.
This is not unlike the ratio of surface area to interior volume, which is a limiting factor for how large (or small) animals can be, before they overheat themselves. So even if we could mount chiller units up the sides of a building – which we can’t, because heat from the lower unit would affect an upper unit – we still have this problem of too much heat in a limited land area.
