frontpage.
newsnewestaskshowjobs

Made with ♥ by @iamnishanth

Open Source @Github

Open in hackernews

Galiliean-invariant cosmological hydrodynamical simulations on a moving mesh

https://wwwmpa.mpa-garching.mpg.de/~volker/arepo/
19•gone35•2d ago

Comments

HelloUsername•4h ago
(HN never fails to give me titles that I can use for my own random music projects :P)
jauntywundrkind•3h ago
> is based on a mov- ing unstructured mesh defined by the Voronoi tessellation of a set of discrete points. The mesh is used to solve the hyperbolic conservation laws of ideal hydrodynamics with a finite volume approach, based on a second-order unsplit Godunov scheme with an exact Riemann solver. The mesh-generating points can in principle be moved ar- bitrarily.

The visual examples at the bottom feel very impressive. I haven't diced fully in, but it feels like there's points where they need to be, that represent the simulation well.

Where-as the previous grids couldn't adapt to the problem.

Neat to see!

ted_dunning•3h ago
This is really nice work that solves a lot of practical problems related to fixed gridding.

I wonder if this could be applied to electromagnetic simulations. Common systems in that field have even more serious problems with gridding.

antognini•2h ago
Worth noting that this paper is from 2009.

For anyone interested they released the code about a decade later: https://arepo-code.org/getting-started

moktonar•2h ago
Do this in time and not only in space, using energy-momentum as the metric and you get Gravity and General Relativity. They are so close and yet they don’t seem to see it.
curt15•56m ago
Is classical HPC still alive and well in the current neural network craze?
semi-extrinsic•13m ago
Definitely. There are techniques that purport to replace traditional PDE solvers (FNOs, LNOs, all sorts of PINNs, ...), but I have yet to see something that can give reasonable predictions of even a second-year grad student level fluid dynamics problem without extensive fine-tuning on an extremely similar problem.

Biomni: A General-Purpose Biomedical AI Agent

https://github.com/snap-stanford/Biomni
36•GavCo•1h ago•6 comments

Tree Borrows

https://plf.inf.ethz.ch/research/pldi25-tree-borrows.html
328•zdw•6h ago•45 comments

Show HN: FlopperZiro – A DIY open-source Flipper Zero clone

https://github.com/lraton/FlopperZiro
104•iraton•3h ago•25 comments

Jank Programming Language

https://jank-lang.org/
109•akkad33•3d ago•16 comments

A fast 3D collision detection algorithm

https://cairno.substack.com/p/improvements-to-the-separating-axis
135•OlympicMarmoto•6h ago•19 comments

Configuring Split Horizon DNS with Pi-Hole and Tailscale

https://www.bentasker.co.uk/posts/blog/general/configuring-pihole-to-serve-different-records-to-different-clients.html
32•gm678•3h ago•6 comments

Desktop Publishing Tools That Didn't Make It (2022)

https://tedium.co/2022/10/12/forgotten-desktop-publishing-tools-history/
24•rbanffy•2h ago•10 comments

Nuclear Waste Reprocessing Gains Momentum in the U.S.

https://spectrum.ieee.org/nuclear-waste-reprocessing-transmutation
45•rbanffy•5h ago•17 comments

Evolution Mail Users Easily Trackable

https://www.grepular.com/Evolution_Mail_Users_Easily_Trackable
73•mike-cardwell•3h ago•41 comments

Archaeologists unveil 3,500-year-old city in Peru

https://www.bbc.co.uk/news/articles/c07dmx38kyeo
80•neversaydie•2d ago•22 comments

Ruby 3.4 frozen string literals: What Rails developers need to know

https://www.prateekcodes.dev/ruby-34-frozen-string-literals-rails-upgrade-guide/
181•thomas_witt•3d ago•88 comments

Why LLMs Can't Write Q/Kdb+: Writing Code Right-to-Left

https://medium.com/@gabiteodoru/why-llms-cant-write-q-kdb-writing-code-right-to-left-ea6df68af443
158•gabiteodoru•1d ago•104 comments

The Architecture Behind Lovable and Bolt

https://www.beam.cloud/blog/agentic-apps
45•Mernit•4h ago•18 comments

US Court nullifies FTC requirement for click-to-cancel

https://arstechnica.com/tech-policy/2025/07/us-court-cancels-ftc-rule-that-would-have-made-canceling-subscriptions-easier/
502•gausswho•22h ago•467 comments

Let Kids Be Loud

https://www.afterbabel.com/p/let-kids-be-loud
59•trevin•1h ago•60 comments

Google fails to dismiss wiretapping claims on SJ, settles with app users

14•1vuio0pswjnm7•1h ago•1 comments

Most RESTful APIs aren't really RESTful

https://florian-kraemer.net//software-architecture/2025/07/07/Most-RESTful-APIs-are-not-really-RESTful.html
252•BerislavLopac•13h ago•389 comments

I Ported SAP to a 1976 CPU. It Wasn't That Slow

https://github.com/oisee/zvdb-z80/blob/master/ZVDB-Z80-ABAP.md
109•weinzierl•2d ago•48 comments

The most otherworldly, mysterious forms of lightning on Earth

https://www.nationalgeographic.com/science/article/lightning-sprites-transient-luminous-events-thunderstorms
20•Anon84•3d ago•6 comments

Bootstrapping a side project into a profitable seven-figure business

https://projectionlab.com/blog/we-reached-1m-arr-with-zero-funding
746•jonkuipers•1d ago•198 comments

TaIrTe₄ photodetectors show promise for sensitive room-temperature THz sensing

https://phys.org/news/2025-07-tairte-photodetectors-highly-sensitive-room.html
10•wglb•3d ago•4 comments

7-Zip for Windows can now use more than 64 CPU threads for compression

https://www.7-zip.org/history.txt
234•doener•2d ago•152 comments

Phrase origin: Why do we "call" functions?

https://quuxplusone.github.io/blog/2025/04/04/etymology-of-call/
213•todsacerdoti•16h ago•152 comments

Helm local code execution via a malicious chart

https://github.com/helm/helm/security/advisories/GHSA-557j-xg8c-q2mm
152•irke882•14h ago•73 comments

RapidRAW: A non-destructive and GPU-accelerated RAW image editor

https://github.com/CyberTimon/RapidRAW
239•l8rlump•18h ago•102 comments

A Emoji Reverse Polish Notation Calculator Written in COBOL

https://github.com/ghuntley/cobol-emoji-rpn-calculator
27•ghuntley•3d ago•5 comments

X Chief Says She Is Leaving the Social Media Platform

https://www.nytimes.com/2025/07/09/technology/linda-yaccarino-x-steps-down.html
288•donohoe•5h ago•413 comments

Is the doc bot docs, or not?

https://www.robinsloan.com/lab/what-are-we-even-doing-here/
181•tobr•13h ago•106 comments

ESIM Security

https://security-explorations.com/esim-security.html
114•todsacerdoti•11h ago•44 comments

Galiliean-invariant cosmological hydrodynamical simulations on a moving mesh

https://wwwmpa.mpa-garching.mpg.de/~volker/arepo/
19•gone35•2d ago•7 comments