Pretending your laptop is a screaming fast workstation and compiling C++ code on all cores can use quite a bit of RAM.
(I have a MacBook Pro that is only around 10% slower at this than an AMD workstation. The workstation has considerably higher TDP. I’m quite impressed.)
On a quick read of the paper, it's incoherent (pun intended). It seems to conflate quantum states with classical vectors, which thoroughly loses both the source of the exponential speedup in Shor's algorithm and the difficulty of quantum algorithm design.
The paper doesn't actually give a clear description of its own algorithm, and there are two specific problems that are apparent even without much of a description:
1. It confuses quantum state vectors with classical vectors or vectors of values. Classically, or on a quantum computer, you can have n values stored in registers or in memory or on a piece of paper or whatever and you have an n-element vector. But on a quantum computer, if you have n qubits and write down their state, you have a 2^n-element vector of complex numbers. These are not the same thing.
So you can have the quantum Fourier transform, which Fourier transforms the coefficients in the state vector of n qubits, which is not at all the same thing as taking 2^n logical numbers and Fourier transforming the numbers.
But this paper very glibly discusses how the QNTT (Quantum Number Theoretic Transform) is nicer than the QFT, but as far as I can tell, the "QNTT" is described in one single paper, doesn't really have much to say for itself, and is actually just an algorithm, supposedly optimized to run on current quantum hardware, that transforms n numbers stored in n registers. (And if a paper wants to claim to number-theoretic-transform the coefficients of a quantum state vector, it should start by explaining how the coefficients of said state vector are to be viewed as elements of a finite ring or field, which these papers do not even pretend to do.)
I think they're using the QNTT to optimize modular exponentiation, which is at least vaguely plausible, but that's using the QNTT for a purpose completely unrelated to what Shor's algorithm uses the QFT for.
2. The replacement of quantum modular exponentiation with classical modular exponentiation is just weird and is completely missing an explanation. Modular exponentiation is just a classical function, like f(r) = 2^r mod p. You can make it reversible (where all operation have inverses) by instead doing somthing like (z, r) -> (z + 2^r mod p, r) -- if you start with z = 0, you get the answer, and if you start with z != 0, you get z added to the answer.
Quantum computers can evaluate quantum functions where the input is qubits instead of classical bits, and they do it by running reversible calculations as above, and many algorithms require doing exactly this while carefully avoiding entangling the inputs or outputs with anything else. So if you start with two quantum registers, you can write the state as complex number times each possible input state (all 2^b of them where b is the total number of bits in all the registers) and you get those same complex numbers times the output states. [0]
The paper claims, with no explanation that I can see, that somehow you can instead do the modular exponentiation on a regular computer and encode those exponents into the quantum circuit. If you are willing to do all 2^b of them, then fine [1], but remember, b is larger than 2048, and this isn't going to work. So maybe they're approximating the modular exponentiation by somehow extrapolating it from a very, very spare set of samples? If that works, that would be quite nifty, but again the paper doesn't appear to so much as acknowledge any complication here. On the other hand, I can easily imagine factoring a number like 15 this way, since the number of samples needed to completely capture the function is rather small.
(I hope I did an okay job of making this both correct and somewhat accessible.)
[0] The calculation is reversible, each input state maps to exactly one output state and vice versa, so each coefficient appears in front of a different logical output state, which makes the math work.
[1] Not fine, because the resulting circuit will be so large that you will never finish running it. But mathematically fine in the sense that you'll get the right answer. Also, by the time you have classically sampled the entire search space for a problem like modular exponentiation, you have already brute forced all possibly discrete logs, at which point you don’t need the quantum computer!
Because there isn't such a relation. It's a thing people believe when they don't have actual experience with peer review. If anything, predatory journals and low-quality pubs can charge more, since publication is more guaranteed (and researchers reaching for these pay-to-publish journals are more desperate).
It's a reputation economy. Like review sites. They start off truthful, and then as time goes on incentives shift to bad actors to subvert it. Or they just sell out their reputation.
Yelp, TripAdvisor, wire cutter, hell even Google results themselves.
Once you start poisoning that well, it's difficult if not impossible to claw it back.
I tend to agree, but keep in mind that most likely you just don't even bother reading the shittiest of the shittiest papers just based on title and abstract. And for every good article there are like 10 unindexed shitty ones.
“Covered application store” means a publicly available internet website, software application, online service, or platform that distributes and facilitates the download of applications from third-party developers to users of a computer, a mobile device, or any other general purpose computing that can access a covered application store or can download an application.
So… DNS servers are “covered application stores”, right? As is PyPI or GitHub or any other such service. S3 and such, too — lots of facilitating going on.
And I’m wondering… lots of things are general purpose computers. Are servers covered? How about embedded systems? Lots of embedded systems are quite general purpose.
edit: Yikes, whoever wrote the text of the law seems to have failed to think at all.
> (b) (1) A developer shall request a signal with respect to a particular user from an operating system provider or a covered application store when the application is downloaded and launched.
The developer shall request? Not the application? So if I write an application and you download it and run it on an operating system, then I need to personally ask your OS how old you are? This makes no sense.
> (2) (A) A developer that receives a signal pursuant to this title shall be deemed to have actual knowledge of the age range of the user to whom that signal pertains across all platforms of the application and points of access of the application even if the developer willfully disregards the signal.
Did they forget to make this conditional on getting g the right answer? If I develop an application used by a 12-year-old and the OS says the user is 18+ (which surely will happen all the time even if no one lies because computers have multiple users), and the OS answers my query, then courts are directed to deem that I have actual knowledge that the user is under 13? Excuse me?
My reading of 2A is that devs can take the word of the OS or App Store. If they say the user’s 18, and the user’s really 13, then the developer’s in the clear for serving adult content to them because they took the word of the certifying entity.
Conversely, if the OS says the user’s 13, then they can’t say they thought the user was actually 18. Guess sucks to suck if you want to buy a movie ticket from your kid’s phone, or if you mistyped your age when you set yours up because you didn’t have your passport nearby.
2A just says that if the e.g. client request headers say the age bracket, the server (dev) can trust the reported age, but also shall not ignore it on purpose. No "just ignore the do-not-track flag" escape hatch here. "A bartender can't willfully refuse to check someone's ID if they are presented with it."
For incorrect OS answers, keep reading. 3B covers what happens if there's clear and convincing evidence that the age covered in 2A is inaccurate. (Reported profile birthday, for instance)
This is "if someone shows a bartender a valid drinking-age ID but says they're celebrating their 17th birthday, this can't be ignored".
Nothing there responds to the question. If my 17 year old answers “I'm 23”, what exactly prevents them from posting to /r/nsfw? What constitutes “clear and convincing evidence”? If there's no answer here, then there appears to be no purpose to this law as this sort of thing is precisely what it's supposed to be preventing.
The difference is a bartender has a handy thing called a human brain that can integrate every evidence and prior without explicit handling. Which a computer program can not. Now we have another "legitimate interest", potentially _forcing_ us to collect biometric and behavioural data we definitely wouldn't monetize to just cover its cost.
> “Covered application store” means a publicly available internet website, software application, online service, or platform that distributes and facilitates the download of applications from third-party developers to users of a computer, a mobile device, or any other general purpose computing that can access a covered application store or can download an application.
So OpenWRT would be covered since they allow the user to download packages (ie software) via apk/opkg.
Quite possibly, yes. Though maybe a router wouldn't qualify as a general purpose computing device, and maybe the packages wouldn't qualify as being from third-party developers when the binaries that get downloaded are both built and distributed by OpenWRT.
I’ve only tried doing a phone repair per iFixit’s instructions once, and the instructions sucked. They explained in excruciating detail how to take the phone apart and then the instructions just ended. No details on reassembly.
What’s wrong with fwupd? I’ll admit that that the CLI is not exactly awesome, but it seems like a fairly clean implementation of the actual UEFI spec for updates.
I disabled possibility of updates in my BIOS, so I must first enter BIOS, enable updates in BIOS, then I have to tinker with my boot configuration as I'm using secureboot with custom keys and no bootloader, I also need to allow changing UEFI boot variables, well, lots of things I just don't want to do for my setup. A lot of moving parts with zero sense over something as simple as update from the USB drive.
Basically right now my setup is super simple and restricted and I have to make it significantly more complicated and insecure to allow fwupd to work.
I haven’t tried to look up the history of this claim, but here are some guesses:
1. There’s a sort of diffusion process going on. Photons from the core have some mean free path as a function of radial position (and, obnoxiously, of wavelength as well, so maybe we ignore that). You could calculate the mean time for a hypothetical object emitted from the core and traveling according to those mean free paths to escape.
2. You could imagine you have marked a photon and watched it travel. This is quite problematic. First, photons in thermal equilibrium obey Bose-Einstein statistics because they are indistinguishable bosons, and anything that could mark them would change the statistics to that of distinguishable particles. But whatever, the temperature is high and maybe this doesn’t matter. Also never mind that those core photons are mostly much shorter wavelength than the photons we see. But you can still imagine. (The answer is probably quite similar to #1 since this is sort of the same problem depending on how you think about the interactions with matter in the sun.)
3. You could calculate how long it would take to notice anything if the core suddenly stopped fusing.
I agree. I read the 5000 years time a few times and I don't like it.
When you have a transparent medium like water or glass, the photon that enters and the photon that exit share a lot of properties, in particular energy/color/frequency. Perhaps they have a shift in the phase or a different polarization (like in water with sugar or if you want to be fancy a quarter wave plate). You can still split a beam before in enter and make interference experiments after half of it passed though water or glass, and other weird experiments, so I think it's fair to call them "the same photon".
But in the Sun, the original photons in the center of the Sun have a few very specific values of energy/color/frequency, that are totally lost. (But the neutrinos have so few interactions that they don't lose this information, and it's possible to do neutrino spectroscopy!)
Also, the photons emitted by the "surface" of the Sun have a wide spectrum of energy/color/frequency that is very close to black body radiation at something like 5000K-6000K.
So in my opinion it's better to think that the original photon in the center is absorbed shortly after it's emitted, and transformed into heat. The heat takes 5000 years to get to the surface. And then the hot surface emits a few new photons unrelated to the original one.
I'm not sure what is the main transmission method inside the Sun: conduction, convection or radiation.
belated edit: My comment about “whatever, the temperature is high” is silly. The mean photon energy is about 2.7kT, which scales in direct proportion the interest bits of the Maxwell-Boltzmann and Bose-Einstein distributions (see [0] and [1]). At 2.7kT, the curves are pretty close, but you don’t have to go down that far to get a big difference. So tagging all the light would cause a substantial change in the sun’s color.
The canonical Q/A pair "Why does the Sun shine?"/"Fusion in its core" perhaps contributes confusion here? Where the question is silently swapped out for "Why is the Sun still shining after 4+ Gyr?". You're primed for a close connection between core and surface photons. Asking "Why is there fog over the uncovered corner of the pool?", one seems unlikely to appreciate "the fog comes from a small aquarium heater somewhere on the bottom!" (IIRC the magnitudes). "The Sun is hot, and hot things glow" creates less of that association between core and light.
> You could calculate how long it would take to notice anything if the core suddenly stopped fusing.
FW(little)IW (very not my field, just AI, quick&sloppy), for a Sun magically switched to contraction-dominated heating, I'm sloping order 10^6-7 yr for a 1% increase in surface temp, with core contraction dynamics being just one uncertainty.
Sometimes the ISA matters. For example, modern ARM has flexible and lightweight atomics, whereas x86 is almost entirely missing non-totally-ordered RMW operations.
> They grew up using Chromebooks … in school, constantly interacting with the local file systems
While it is possible to interact with the local file system on a school Chromebook, it’s certainly not the default. School interactions with Chromebooks seem to consist of logging with highly secure passwords like “strawberry” and using Google Docs. And playing games with heavy PvP components and paid DLC (paid by parents whose kids beg for it, not by schools) that call themselves “educational” because they interject math problems needed to use those juicy spells, make no effort whatsoever to teach anything, but produce a nicely formatted report correlating scores to numbered elements of the Common Core standards.
> Featuring extensive connectivity to support a variety of workflows, Studio Display XDR includes two Thunderbolt 5 ports and two USB-C ports.
That is not extensive connectivity. That’s the bare minimum one might credibly expect.
If I were to consider buying a display like this, I would want at least two and preferably more inputs and at least a DisplayPort input. Not everything in the world is USB-C, especially when discrete GPUs are involved.
If I had to guess, with so many devices (speakers, microphone, webcam) on top of any external ones you connect, having multiple inputs especially one that can't possibly connect your computer to those devices, is virtually guaranteeing that some users will complain that it doesn't work. I believe there is a similar reason why usb-c hubs rarely have downstream usb-c ports. When you do find one, they always have several reviews complaining that it doesn't work with 3 hard drives and 2 monitors plugged in.
(I have a MacBook Pro that is only around 10% slower at this than an AMD workstation. The workstation has considerably higher TDP. I’m quite impressed.)
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