Hi, this is me. I'm still hacking on it but ran into some hard to understand kernel bugs. once i mount more than the root filesystem (say /usr/man) there are issues with inode allocation/freeing. mixing and matching v4 and v5 stuff in various ways can also lead to other interesting bugs but often an allocated inode ends up on the freelist, and things break.
Otoh it's so much fun to hack and fiddle with the unix kernel :) very zen
> but ran into some hard to understand kernel bugs
Are the bugs in the original, or somehow artifacts of how we got it? (Or, phrased differently: Were these bugs present at the University of Utah in 1974, or are they "new"?)
That's the puzzling thing. i find it hard to believe they sent out an operating system that can't deal with multiple file systems. yet i can't get them to work correctly. The pre-v4 nsys kernel is another piece in the puzzle. it doesn't have pipes implemented yet but aside from that (i put them in) it also shows these "busy i" bugs, but even when running on a single disk. Maybe there's more i'm doing wrong there since it's running on the fs from the v4 tape. But that i'm getting such similar bugs in different situations suggests there is something wrong that i'm not seeing yet. gotta debug more.
If it turns out to be a timing-related bug it may be that the bug was much less obvious on real hardware.
a) Do these inode issues also happen with the supplied (v4) kernel?
b) Do these inode issues also happen with a rebuilded kernel which uses the original lib1 and lib2?
I once had strange effects on V6 if lib1 and/or lib2 were rebuild by me.
I find it strange that nobody has ever recreated the classic windows desktop faithfully, except for reactos i suppose. But on Linux i think there are quite a few people around who would happily use it. All sorts of themes for other interfaces aren't quite the same thing
Nobody ever considers the spinorial version. e^iπ is a 360° rotation on a spinor, and + is averaging spinors rotationally. so e^iπ + 1 = 0 means there is no way to interpolate between the identity and a twist in the spinor, because the axis of a 360° rotation is undefined.
Things get so much more fun once you embrace spinors.
I've wanted to try racket a few times but always found the "IDE" to be really unintuitive, clunky and weird. What gives? Is that by design or is it just that nothing better has been created so far?
The Racket Langserver obviously enables use in other editors that support the LSP. https://github.com/jeapostrophe/racket-langserver For editors that lack LSP support, scheme support is generally sufficient.
All that aside, DrRacket the IDE has some nice features that just don't exist in other editors. I don't know of another IDE that has an integrated macro stepper.
Yup! I used to use FreeBSD on my thinkpad but as time went on that became less practical and I've been on Linux ever since. First arch and then void kinda filled the spot. void feels a bit like home.
Unfortunately I can't help with the classical picture, but in quantum physics it all comes out very nicely:
You can interpret the Lagrangian as giving all possibilities to build a trajectory through spacetime. In the path integral formulation we then follow one such trajectory from one configuration to another configuration and find its amplitude.
And then we integrate over all possible trajectories that we could have picked. For incoherent trajectories there will always be another one that cancels out the amplitude. Where the amplitudes add up constructively you will find stationary action and the classical behavior in the limit.
So this is a depth-first approach: first follow one trajectory completely, then add up all possible trajectories.
The Hamiltonian approach in contrast is breadth-first:
you single out a time axis, start with some initial state, and consider all possibilities that a particle (or field in QFT) could evolve forwards in time just a tiny bit (this is what the Hamiltonian operator does). Then you add up all these possibilities to find the next state, and so you move forwards through time by keeping track of all possible evolutions all at once. This massive superposition of everything that is possible (with corresponding amplitudes) is what you call a state (or wavefunction) and the space that it lives in is the Hilbert (or Fock) space.
So Lagrangian/path-integral: follow full trajectories, then add up all possible choices. depth-first
Hamiltonian/time-evolution: add up all choices for a tiny step in time, then simply do more steps: breadth-first
I imagine it a bit like a scanline algorithm calculating an image as it moves down the screen (Hamiltonian) vs something like a stochastic raytracer that can start with an empty image and refine it pixel by pixel by shooting more rays (Lagrangian)
This is my layman explanation anyways...hopefully it helps, even though i can't say much about their relationship in classical physics.
Otoh it's so much fun to hack and fiddle with the unix kernel :) very zen
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