Posted by AriFordsham 2 hours ago
That's not to say there isn't value in formal correctness, but the important part is identifying when it's useful and when its more trouble than its worth...
Think about the filesystem, the big issue with formalizing a program spec that operates on a file system is simply the fact it is essentially a shared object amongst all the programs running on the system. Add to that the fact that (though this changes with modern containerization systems, namespaces, pledge what ever) a program may at any point gain access to root permissions if it makes the system call to do so providing the correct credentials it becomes very difficult formally be able to remove any possible states from the system.
All this could be different but we would radically need to redesign are systems and the way we think about the problems.
While these areas were main premise of an article when it was written, I think the article really aged well into current time of mass AI/LLM deployment. It shows fundamental limitations of token based systems / symbolic reasoning that LLM espouses internally, while writing correct software. These limitations also apply to humans, however humans mental modelling, being not fully based on symbolic processing, have been historically shown capable of writing correct software systems, while AI/LLM systems have not been proven to be able to do that, and as article shows that with current token based technology it's unlikely they will ever be.
I think those domains has more stringent requirement and a more focused usage, making the classes of inout narrower. A lot of software for B2B and B2C tries to be a kitchen sink and in the result get turned into a ball of mud. Some stuff should just be separate software.
Some API:s can be perfect. But then the real world adaptation needs to happen inside the module serving the API.
This does not require proving systems complete correct, but it does involve proving many properties of these systems.
So I had to reconstruct a signal that fitted the data for the equations to work at all. But the reconstruction was no longer measured data. It was made up, and there was no single solution for fitting the data. That meant I could claim to "respect the data" while producing any result I wanted.
a fun one that immediately comes to mind is asserting something holds for reals, but not evaluating whether it holds for IEEE floats, though maybe that's not really a thing in finance due to rounding related rules anyways
It's nice to see this older discussion of the topic outside of 'AI does lean' and the assumptions that formally verification is easy or will be easy for AI and you can just switch you brain off.
Build programs that can be verified in the first place is difficult design problem that requires real thought and deep insight of the problem.
I don't care about the examples given, I care about my word processor, web browser and such. Can we prove them - putting limits on the scripting language
I might want my code to dabble in CORS, read env vars, or snoop around in my .ssh directory, but I don't want my imports to be able to do that.
OpenBSD has a (partial?) solution for that: pledge (2)
https://man.openbsd.org/OpenBSD-6.7/pledge.2
Often, a programming needs a lot of rights at the start to set things up (often even root permissions). After this has been done, it should better have irrevocable limited rights. The pledge() syscall is there to do this transition:
"Subsequent calls to pledge() can reduce the abilities further, but abilities can never be regained."
Putting limits on a scripting language should not be too hard (even without talking about any correctness proof). And I would bet that for a scripting language where the limits are in a way that "in a correct implementation, it should be highly likely that these limits are actually enforced" (i.e. the specification of the scripting language has no parts that makes you suspicious whether there exists some loophole that a malicious actor could use to overstep the limits), it should actually be possible to write a verified implementation with some effort.
But this is not what people want: for example, basically every evolution of the web standards since HTML5 by the WHATWG was about extending what is possible to do in the scripting language (JavaScript).
A lot of modern programs never terminate and thus to me "halting" means no longer able to compute, i.e it's hung/deadlocked.
Computer Science historically being seen as a gateway to software development has done a large disservice to both fields.
And an astronomer should absolutely have understanding of those, their intricacies, the optical equations involved, and how to operate them (usually with automated software, but astronomers are the ones writing that software).
Now an astrophysicist has less to do with telescopes, especially if your field is theoretical cosmology, although they still require familiarity with telescopes, practicalities, how observations are made etc. because that is the basis of their theory. So, a cosmologist vs. an astronomer might be a better analog for a computer scientist vs. a software engineer.
And I know that despite doing my own thesis in cosmology, my studies involved a lot of knowledge and teaching about telescopes, including at least one night of observations (it's pretty boring, things are very automated).
- Computer science is about extending our understanding what can be done with computers (including what can be done efficiently). The computer scientist in this story exactly does that: he sees that the usage of the poster is a special case of a much more general pattern, and tries to understand this pattern, so that a solution that is developed for the general case can be applied to all of them, without having to develop a novel solution for every new case, which can save an insane amount of money.
- The kind of requirement analysis, and process orientation is rather untypical for computer scientists, but rather for what is called in German "Wirtschaftsinformatiker" (i.e. people who are business process analysts first and programmers second). These are people who are deep in love with such analysis paralysis, not the typical programmer or computer scientist who is often quite suspicious of such concepts.
In other words: if your toilet is clogged, you call a plumber, and not an expert in fluid dynamics.
La Palma - Gateway to the Universe (November 9, 2026)
The team journey to La Palma, where giant new telescopes and cutting-edge science are opening extraordinary new windows on our universe.
Roque de los Muchachos Observatory - https://en.wikipedia.org/wiki/Roque_de_los_Muchachos_Observa...
A heck of a lot. Your professor clearly does not know much about astronomy.
For example if you have a whole bunch of Hydrogen the gravity its exerting on itself is negligible... Unless it's a lot of Hydrogen because eventually instead of being negligible the gravity adds up to where the Hydrogen atoms undergo nuclear fusion and that's how you get stars.
Similarly, Oceanography does have boats and a large building next to the sea, but although some of them are capable sailors, a lot of what they're interested in is theoretical and doesn't require you to even be able to smell the sea, let alone go out on it.
The same can be said about computers and computer science. I don't think I fully agree with that, but it's interesting to think about.
The terminology of the "halting problem" is a very specific term of computer science, and it didn't age badly. This is like saying a reactor "going critical" hasn't aged well because non-physicists don't understand what "critical" means: it's not meant for them. Or about "prime numbers" because non-mathematicians don't know what "prime" means. Or what a "continuous function" is, etc, etc. You get the idea.
Modern programs are still composed of functions, and those functions are subject to the halting problem, in the sense that they get inputs and provide outputs. If they don't, they did not "compute" in precisely the sense you meant it. So let's say your videogame or whatever is waiting for input (the joystick or mouse) and you don't provide it, and because it's a turn-based game, nothing else happens. Has it "halted" in the sense we're discussing? Nope. It would be subject to halting if, once you provide input, the program cannot produce the intended result for your input (move a sprite, display "game over", start another round, play an animation, modify internal game state, etc).
In other words, Computer Science talks of "programs" but it's really any computation that takes an input and produces an output, and modern programs are made of them, so the problem applies to them.
Management and marketing can only cope with a vague, third party description of the sheet.