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Cake day: July 7th, 2024

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  • Honestly, the random number generation on quantum computers is practically useless. Speeds will not get anywhere near as close to a pseudorandom number generator, and there are very simple ones you can implement that are blazing fast, far faster than any quantum computer will spit out, and produce numbers that are widely considered in the industry to be cryptographically secure. You can use AES for example as a PRNG and most modern CPUs like x86 processor have hardware-level AES implementation. This is why modern computers allow you to encrypt your drive, because you can have like a file that is a terabyte big that is encrypted but your CPU can decrypt it as fast as it takes for the window to pop up after you double-click it.

    While PRNG does require an entropy pool, the entropy pool does not need to be large, you can spit out terabytes of cryptographically secure pseudorandom numbers on a fraction of a kilobyte of entropy data, and again, most modern CPUs actually include instructions to grab this entropy data, such as Intel’s CPUs have an RDSEED instruction which let you grab thermal noise from the CPU. In order to avoid someone discovering a potential exploit, most modern OSes will mix into this pool other sources as well, like fluctuations in fan voltage.

    Indeed, used to with Linux, you had a separate way to read random numbers directly from the entropy pool and another way to read pseudorandom numbers, those being /dev/random and /dev/urandom. If you read from the entropy pool, if it ran out, the program would freeze until it could collect more, so some old Linux programs you would see the program freeze until you did things like move your mouse around.

    But you don’t see this anymore because generating enormous amounts of cryptographysically secure random nubmers is so easy with modern algorithms that modern Linux just collects a little bit of entropy at boot and it uses that to generate all pseudorandom numbers after, and just got rid of needing to read it directly, both /dev/random and /dev/urandom now just internally in the OS have the same behavior. Any time your PC needs a random number it just pulls from the pseudorandom number generator that was configured at boot, and you have just from the short window of collecting entropy data at boot the ability to generate sufficient pseudorandom numbers basically forever, and these are the numbers used for any cryptographic application you may choose to run.

    The point of all this is to just say random number generation is genuinely a solved problem, people don’t get just how easy it is to basically produce practically infinite cryptographically secure pseudorandom numbers. While on paper quantum computers are “more secure” because their random numbers would be truly random, in practice you literally would never notice a difference. If you gave two PhD mathematicians or statisticians the same message, one encrypted using a quantum random number generator and one encrypted with a PRNG like AES or ChaCha20, and asked them to decipher them, they would not be able to decipher either. In fact, I doubt they would even be able to identify which one was even encoded using the quantum random number generator. A string of random numbers looks just as “random” to any random number test suite whether or not it came from a QRNG or a high-quality PRNG (usually called CSPRNG).

    I do think at least on paper quantum computers could be a big deal if the engineering challenge can ever be overcome, but quantum cryptography such as “the quantum internet” are largely a scam. All the cryptographic aspects of quantum computers are practically the same, if not worse, than traditional cryptography, with only theoretical benefits that are technically there on paper but nobody would ever notice in practice.




  • Why are you isolating a single algorithm? There are tons of them that speed up various aspects of linear algebra and not just that single one, and many improvements to these algorithms since they were first introduced, there are a lot more in the literature than just in the popular consciousness.

    The point is not that it will speed up every major calculation, but these are calculations that could be made use of, and there will likely even be more similar algorithms discovered if quantum computers are more commonplace. There is a whole branch of research called quantum machine learning that is centered solely around figuring out how to make use of these algorithms to provide performance benefits for machine learning algorithms.

    If they would offer speed benefits, then why wouldn’t you want to have the chip that offers the speed benefits in your phone? Of course, in practical terms, we likely will not have this due to the difficulty and expense of quantum chips, and the fact they currently have to be cooled below to near zero degrees Kelvin. But your argument suggests that if somehow consumers could have access to technology in their phone that would offer performance benefits to their software that they wouldn’t want it.

    That just makes no sense to me. The issue is not that quantum computers could not offer performance benefits in theory. The issue is more about whether or not the theory can be implemented in practical engineering terms, as well as a cost-to-performance ratio. The engineering would have to be good enough to both bring the price down and make the performance benefits high enough to make it worth it.

    It is the same with GPUs. A GPU can only speed up certain problems, and it would thus be even more inefficient to try and force every calculation through the GPU. You have libraries that only call the GPU when it is needed for certain calculations. This ends up offering major performance benefits and if the price of the GPU is low enough and the performance benefits high enough to match what the consumers want, they will buy it. We also have separate AI chips now as well which are making their way into some phones. While there’s no reason at the current moment to believe we will see quantum technology shrunk small and cheap enough to show up in consumer phones, if hypothetically that was the case, I don’t see why consumers wouldn’t want it.

    I am sure clever software developers would figure out how to make use of them if they were available like that. They likely will not be available like that any time in the near future, if ever, but assuming they are, there would probably be a lot of interesting use cases for them that have not even been thought of yet. They will likely remain something largely used by businesses but in my view it will be mostly because of practical concerns. The benefits of them won’t outweigh the cost anytime soon.


  • Uh… one of those algorithms in your list is literally for speeding up linear algebra. Do you think just because it sounds technical it’s “businessy”? All modern technology is technical, that’s what technology is. It would be like someone saying, “GPUs would be useless to regular people because all they mainly do is speed up matrix multiplication. Who cares about that except for businesses?” Many of these algorithms here offer potential speedup for linear algebra operations. That is the basis of both graphics and AI. One of those algorithms is even for machine learning in that list. There are various algorithms for potentially speeding up matrix multiplication in the linear. It’s huge for regular consumers… assuming the technology could ever progress to come to regular consumers.


  • A person who would state they fully understand quantum mechanics is the last person i would trust to have any understanding of it.

    I find this sentiment can lead to devolving into quantum woo and mysticism. If you think anyone trying to tell you quantum mechanics can be made sense of rationally must be wrong, then you implicitly are suggesting that quantum mechanics is something that cannot be made sense of, and thus it logically follows that people who are speaking in a way that does not make sense and have no expertise in the subject so they do not even claim to make sense are the more reliable sources.

    It’s really a sentiment I am not a fan of. When we encounter difficult problems that seem mysterious to us, we should treat the mystery as an opportunity to learn. It is very enjoyable, in my view, to read all the different views people put forward to try and make sense of quantum mechanics, to understand it, and then to contemplate on what they have to offer. To me, the joy of a mystery is not to revel in the mystery, but to search for solutions for it, and I will say the academic literature is filled with pretty good accounts of QM these days. It’s been around for a century, a lot of ideas are very developed.

    I also would not take the game Outer Wilds that seriously. It plays into the myth that quantum effects depend upon whether or not you are “looking,” which is simply not the case and largely a myth. You end up with very bizarre and misleading results from this, for example, in the part where you land on the quantum moon and have to look at the picture of it for it to not disappear because your vision is obscured by fog. This makes no sense in light of real physics because the fog is still part of the moon and your ship is still interacting with the fog, so there is no reason it should hop to somewhere else.

    Now quantum science isn’t exactly philosophy, ive always been interested in philosophy but its by studying quantum mechanics, inspired by that game that i learned about the mechanic of emerging properties. I think on a video about the dual slit experiment.

    The double-slit experiment is a great example of something often misunderstood as somehow evidence observation plays some fundamental role in quantum mechanics. Yes, if you observe the path the two particles take through the slits, the interference pattern disappears. Yet, you can also trivially prove in a few line of calculation that if the particle interacts with a single other particle when it passes through the two slits then it would also lead to a destruction of the interference effects.

    You model this by computing what is called a density matrix for both the particle going through the two slits and the particle it interacts with, and then you do what is called a partial trace whereby you “trace out” the particle it interacts with giving you a reduced density matrix of only the particle that passes through the two slits, and you find as a result of interacting with another particle its coherence terms would reduce to zero, i.e. it would decohere and thus lose the ability to interfere with itself.

    If a single particle interaction can do this, then it is not surprising it interacting with a whole measuring device can do this. It has nothing to do with humans looking at it.

    At that point i did not yet know that emergence was already a known topic in philosophy just quantum science, because i still tried to avoid external influences but it really was the breakthrough I needed and i have gained many new insights from this knowledge since.

    Eh, you should be reading books and papers in the literature if you are serious about this topic. I agree that a lot of philosophy out there is bad so sometimes external influences can be negative, but the solution to that shouldn’t be to entirely avoid reading anything at all, but to dig through the trash to find the hidden gems.

    My views when it comes to philosophy are pretty fringe as most academics believe the human brain can transcend reality and I reject this notion, and I find most philosophy falls right into place if you reject this notion. However, because my views are a bit fringe, I do find most philosophical literature out there unhelpful, but I don’t entirely not engage with it. I have found plenty of philosophers and physicists who have significantly helped develop my views, such as Jocelyn Benoist, Carlo Rovelli, Francois-Igor Pris, and Alexander Bogdanov.


  • This is why many philosophers came to criticize metaphysical logic in the 1800s, viewing it as dealing with absolutes when reality does not actually exist in absolutes, stating that we need some other logical system which could deal with the “fuzziness” of reality more accurately. That was the origin of the notion of dialectical logic from philosophers like Hegel and Engels, which caught on with some popularity in the east but then was mostly forgotten in the west outside of some fringe sections of academia. Even long prior to Bell’s theorem, the physicist Dmitry Blokhintsev, who adhered to this dialectical materialist mode of thought, wrote a whole book on quantum mechanics where the first part he discusses the need to abandon the false illusion of the rigidity and concreteness of reality and shows how this is an illusion even in the classical sciences where everything has uncertainty, all predictions eventually break down, nothing is never possible to actually fully separate something from its environment. These kinds of views heavily influenced the contemporary physicist Carlo Rovelli as well.