HNHacker News
TopNewBestAskShowJobs

v_lisivka

0 karma · joined December 14, 2017

Ukrainian from Ukraine.

Volodymyr M. Lisivka vlisivka@gmail.com

Don't forget to quote me!

submissionscomments
v_lisivka··on World of Goo Update, 10 Years Later
I'm ready. Will you pay for my work to achieve your goal?
v_lisivka··on Tesla sued in wrongful death lawsuit that alleges Autopilot caused crash
It's driver responsibility to drive the car and pay attention to the road.
v_lisivka··on Tesla sued in wrongful death lawsuit that alleges Autopilot caused crash
Autopilot is just autopilot. There was lot of plane crashes with autopilot involved.

https://www.youtube.com/watch?v=FLrIXptqZxw

v_lisivka··on System76 News: Coreboot and Linux Advances
Yeah, Dell XPS + Fedora works great together. I actually started to use Bluetooth with Dell. It just works.
v_lisivka··on Next-Paradigm Programming Languages: What Will They Look Like?
Goal-based language (similar to Makefile's), driven by AI, with automatic error handling of any kind.
v_lisivka··on Next-Paradigm Programming Languages: What Will They Look Like?
Add a plugin to your IDE, to display embedded graphics from comments.
v_lisivka··on Mystery of the Universe’s Expansion Rate Widens with New Hubble Data
I saw math paper about systems, which can remain stable for unlimited time. As far as I remember, infinity number of solutions exist for 1D, and 2D worlds. Only 3 solutions found for 3D world (named 1, 2, and 42). None found for 4D world, so, if infinite time given, 4D world will collapse into 3D world.

I can't find this paper again yet. (I'm quite busy: revolution, ongoing war, problems with health, my father died, politics, delivery for 1+y long project in less than 2 weeks, etc.)

This paper complimented view I already had in my head (everything is particle, surrounded by spherical wave, and propelled by vibrations/noise), because now I know that Universe is very simple thing in general. Nothing complex can survive in infinite time. This mean that on lower level only extremely stable (simple) systems can survive, because time is very fast on level below. On our level, we can find temporary complex systems (we live at one of them, and we itself are another example). On level above, it unlikely that we will find a complex system, chances are very low, thus what is see around us should continue for very long time and space.

v_lisivka··on Fedora 30
CentOS 8 is not fresh enough for you?
v_lisivka··on Fedora 30
I have binary NVidia drivers. I have no problem with upgrades for last few releases at least (since akmod invented).

Sometimes, I need to switch from supported release to legacy release of drivers or switch back, because of NVidia politics to remove old drives from binary.

v_lisivka··on Fedora 30
Yep. Even simple `dnf upgrade -y && dnf updrade --releasever=30 -y` should work, because difference between releases is small enough. (No groundbreaking changes). I did upgrade from Fedora 26 to Fedora 28 using simple upgrade.

Recommended command for system upgrade is `sudo dnf system-upgrade download --refresh --releasever=30` then `sudo dnf system-upgrade reboot` .

v_lisivka··on Mystery of the Universe’s Expansion Rate Widens with New Hubble Data
> angular power spectrum of the CMB

My bad. I'm not familiar with this.

(Beware, my English is weak).

I had year long discussion about similar topic by email, so I see nothing exceptional there. If you have sum(sin(x_natscale)), and you will start to play with scale, you will see sinusoidal graphic, freq=asin(scale). Object formations in space usually have round shape, so it's will be same in 3D. :-/

Why? Because our formation exists for very long time. Let's play simple example: we need a 1d function f(x), such as sum(f(x_nat*scale)) newer produces infinite sum or singularity. Physical meaning: Our Universe exists for infinite time, but all matter is not attracted into one single point of infinite mass, so it's not possible.

The simplest such function is sin(x) or cos(x). If we will try to play with scale, we newer be able to make infinite sum, because Pi is irrational number. The closer our scale will be to Pi, the larger peaks of sum we will have.

In real life, this influence diminishes after some point, so, for example, size of nuclei has influence at frequency (distribution) of chemical elements, but it has no influence at macro objects, so function becomes flat and sum must rise (e.g. collapse into a black hole), then next level begins.

So, it looks like at some point, these formations cannot be bigger, or we cannot see light from them, e.g. because they are so massive, so light cannot escape them. If so, we have lower limit of formation size we can see at this distance, dictated by geometry (angular size) and luminosity, and upper limit dictated by nature, e.g. upper mass of formation of such size (upper density).

It's like in our galaxy: we can see stars, but cannot see black holes (too heavy), lone planets and smaller objects (too cold), and far away objects after certain distance (too small luminosity). IMHO, angular power spectrum of visible stars must show distribution similar to CMB or distribution of chemical elements.

v_lisivka··on Mystery of the Universe’s Expansion Rate Widens with New Hubble Data
> Because the other theories we leave behind do not make predictions compatible with our measurements of the universe.

It's temporary. With more data, we will have more and more exceptions, which cannot be explained by patches to mainstream theory.

>> so there was no Big Bang less than nanosecond ago at Universe scale

> What is this supposed to mean?

Lifetime of larger objects usually is much larger than lifetime of smaller objects, so, as we increase scale of x,y,z, t axis should be increased proportionally.

> You mean red-shifting or something else here?

Modern version of tired light. A kind of resistance for light, which causes loss of energy proportional to light frequency. See below.

> How do you account for the CMB angular power spectrum[1][2] with your "tired light"?

I see just aged spectrum. IMHO, it's helium. :-/

v_lisivka··on Mystery of the Universe’s Expansion Rate Widens with New Hubble Data
Not exactly. In tired light theory, red shift of light is result of scattering, which is very unlikely, because scattering changes course of photon, so these photons will not be associated with original object after some very short distance.

My own idea is that photon itself has no mass, because it just wave of energy, but vacuum of volume of photon has some non-zero mass.

As analogy, water wave has no mass, but water has, so water, which forms wave, can be affected by external forces, e.g. gravitation of Moon and Sun, thus form of water wave can be disturbed by these forces. LIGO demonstrated that light can be affected by gravitational waves, so these gravitational waves, in form of constant noise, can disturb shape of photon, so photon will lost small fraction of energy to gravitational field.

Moreover, as EM force, photon should be affected by fluctuations of quantum foam, which are happened nearby. In this case, photon will lose small fraction of energy to these virtual particles.

v_lisivka··on Mystery of the Universe’s Expansion Rate Widens with New Hubble Data
The mystery is why only one theory is accepted, while all other are left behind.

For me, it's clear that Universe has no bounds, so objects after Visible Universe is invisible because of geometry - we just cannot see objects which are sending less than 1 photon per hour per square meter, so there was no Big Bang less than nanosecond ago at Universe scale, it's just aging of light, so background microwaves is just aged light from distant objects.

v_lisivka··on Stop Memsetting Structures
RDMA (Infiniband) does DMA to/from network. Why we should not use RDMA?
v_lisivka··on Google search only has 60% of my content from 2006
Yep.
v_lisivka··on Google search only has 60% of my content from 2006
Simple Bloom filter, generated and published by site itself, can lower the curve a lot.
v_lisivka··on Google search only has 60% of my content from 2006
It's another question: https://stackoverflow.com/questions/50475428/css-grid-is-not...
v_lisivka··on Programming language ray tracing benchmarks project
Rust is compiled by LLVM, while C compiled by GCC, which is a bit conservative. It's possible to enable same optimizations for gcc and LLVM, so their speed will match.
v_lisivka··on Some Were Meant for C (2017) [pdf]
Yep, UNIX is the IDE for C. UNIX contain C compiler by default, which makes it very easy to distribute programs written in C.
v_lisivka··on Some Were Meant for C (2017) [pdf]
> All the listed weaknesses also have benefits. For instance it is easy to get a substring without need to copy.

To make substring in some other languages, you need to store pointer to beginning of the substring and length of substring.

To make substring in C, you need to store pointer to beginning of the substring and put '\0' into original string.

v_lisivka··on Show HN: WAPM – Package Manager for WebAssembly
Is it possible to integrate wapm with web browser as plugin, so web site will be able to request up-to date wasm packages from local store instead of downloading of their own copies?
v_lisivka··on Rust's 2019 Roadmap
Can anybody explain the downvotes? It looks suspicious.

It's well known and long standing problem. Rust the Language allows proper enum, but Rust the Compiler cannot pack enum into single value, as in C.

Example:

  #[repr(C)]
  #[repr(i32)]
  #[derive(Debug)]
  #[allow(dead_code)]
  enum E {
    A,
    B,
    C,
    Unlabeled(i32),
  }

  fn main() {
    {
        let v: E = unsafe { std::mem::transmute::<(i32,i32), E>((0,0)) };
        println!("v = {:?}", v)
    }
    {
        let v: E = unsafe { std::mem::transmute::<(i32,i32), E>((1,1)) };
        println!("v = {:?}", v)
    }
    {
        let v: E = unsafe { std::mem::transmute::<(i32,i32), E>((2,2)) };
        println!("v = {:?}", v)
    }
    {
        let v: E = unsafe { std::mem::transmute::<(i32,i32), E>((3,3)) };
        println!("v = {:?}", v)
    }
    {
        let v: E = unsafe { std::mem::transmute::<(i32,i32), E>((3,55)) };
        println!("v = {:?}", v)
    }
    {
        let v: E = unsafe { std::mem::transmute::<(i32,i32), E>((55,55)) };
        println!("v = {:?}", v)
    }
  }

Output:

  v = A
  v = B
  v = C
  v = Unlabeled(3)
  v = Unlabeled(55)
  v = A
v_lisivka··on Rust's 2019 Roadmap
One long-standing problem is the incompatibility of Rust enum with C enum. In C, enum's are just labels for integers, similar to const int values in Rust, so C enum { A=0, B=1, C=2 } is more like Rust's enum E { A=0, B=1, C=2, Unlabeled(3..MAX_INT32), } . This slight incompatibility forces writing of converters between C enums and Rust enums.

See https://github.com/rust-lang/rust-bindgen/issues/667

v_lisivka··on Fukushima: Removal of nuclear fuel rods from damaged reactor building begins
Yep, in form of 6% sale tax.
v_lisivka··on Rust: Beyond the Typechecker
Too many years are passed, but as far as I remember, only C code was portable between 8, 16, and 32 bit platforms. It was possible to incrementally convert program from assembler to C and then port to different platforms, but it was not possible to do conversion using Pascal, or other programming language.
v_lisivka··on Rust: Beyond the Typechecker
Because, C is portable assembler. In Pascal, for example, if something cannot be done in Pascal, then assembler must be used. If assembler is used, then program is tied to single platform. If you need to support two or more platforms at same time over long period, then C wins.
v_lisivka··on Fukushima: Removal of nuclear fuel rods from damaged reactor building begins
> That's said, Earth at its worse is still probably infinitely more livable than Mars at its best.

Except for taxes. Anybody, who will live on Earth and be above average, will need to support other living beings (humans, animals, fish, forest, grass, birds, insects) with his taxes, otherwise we will have dirty cloak with few billions of angry and hungry living beings, which can dig you out of any bunker.

At Mars, it will be hard to survive without external support for about century, but much lower taxes and self selection of educated people with high IQ can make it booming.

v_lisivka··on Moving to a provenance-aware memory object model for C: proposal for C2x
> Please tell that to the many millions of C/C++ programmers writing new code every day, who are only vaguely familiar with Rust if at all.

Just call it "C20", and they will learn it in a week.

v_lisivka··on Languages I want to write
> If I write some garbage and ask the computer to run it, what should happen?

You will be pushed. J

Seriously talking, if I need to wrote error checking code with user visible message, usually I'm trying to add a suggestion to user how to resolve problem. It's good UX.

← PreviousPage 2 of 20Next →