<rss version="2.0" xmlns:dc="http://purl.org/dc/elements/1.1/" xmlns:atom="http://www.w3.org/2005/Atom"><channel><title>Hacker News: pfdietz</title><link>https://news.ycombinator.com/user?id=pfdietz</link><description>Hacker News RSS</description><docs>https://hnrss.org/</docs><generator>hnrss v2.1.1</generator><lastBuildDate>Tue, 18 Aug 2026 00:57:52 +0000</lastBuildDate><atom:link href="https://hnrss.org/user?id=pfdietz" rel="self" type="application/rss+xml"></atom:link><item><title><![CDATA[New comment by pfdietz in "The Case Against Formal Verification, 50 Years Later"]]></title><description><![CDATA[
<p>> Ordinary testing using a few handpicked example<p>Ah, but if you have specifications, you should have the ability to generate unlimited numbers of tests.  Handpicked examples aren't needed.   The great advance in testing with increase in compute power was the realization that carefully handcrafted tests are silly; just blast huge amounts of randomness at the system and use cheap compute to save expensive human effort.<p>I think it's a common experience to implement some well-defined data structure or algorithm and use the clear specification of its behavior to randomly test it, to then discover this flushes out all the bugs.</p>
]]></description><pubDate>Mon, 17 Aug 2026 02:17:36 +0000</pubDate><link>https://news.ycombinator.com/item?id=49325875</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49325875</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49325875</guid></item><item><title><![CDATA[New comment by pfdietz in "AI isn’t outthinking mathematicians, it’s out-remembering them"]]></title><description><![CDATA[
<p>Lean terms and programs have defined meanings, just like anything mathematical does.<p>It sounds like you're asking something nebulous, like does it have a soul.<p>Mass generation of conjectures and proofs/disproofs could AI to discover objectively mathematically useful things.  For example, it might discover shortcuts, lemmas, even abstractions that are useful in the proofs of these things -- and judge that utility by how much they improve the ability of the AI to prove things in this mass of problems.  It wouldn't say whether the things are useful for non-mathematical human problems, but then human mathematicians, as you say, can't really judge that either.</p>
]]></description><pubDate>Mon, 17 Aug 2026 01:43:11 +0000</pubDate><link>https://news.ycombinator.com/item?id=49325703</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49325703</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49325703</guid></item><item><title><![CDATA[New comment by pfdietz in "St Lucie Nuclear Reactor Unit 1 manually shutdown, 3 control rods drop into core"]]></title><description><![CDATA[
<p>Yes.  Note that fuel rods don't move, so they would not "drop into the core".  They can later be lifted out when the reactor is refueled but are fixed in place when the reactor is in operation.</p>
]]></description><pubDate>Sun, 16 Aug 2026 22:56:00 +0000</pubDate><link>https://news.ycombinator.com/item?id=49324613</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49324613</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49324613</guid></item><item><title><![CDATA[New comment by pfdietz in "Secondhand book sales are booming. Is it because of AI?"]]></title><description><![CDATA[
<p>So, if Google consciously throws books in the trash, that's ok, but if they scan them first, that's not ok?<p>Or maybe this is just a thin veneer over anti-techbro antipathy.<p>If destroying a book is such an evil, then isn't not printing a book also a huge net negative?  Are you going to call on publishers to make endless print runs to churn out books that then get warehoused?  I mean, if these lumps of cellulose are such inherently valuable objects, wouldn't we create endless value by piling up the unread copies?</p>
]]></description><pubDate>Sun, 16 Aug 2026 22:47:45 +0000</pubDate><link>https://news.ycombinator.com/item?id=49324551</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49324551</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49324551</guid></item><item><title><![CDATA[New comment by pfdietz in "The Case Against Formal Verification, 50 Years Later"]]></title><description><![CDATA[
<p>Empirically, we can look at something like CompCert, which formally verified a substantial section of a C compiler.<p>Subsequent high volume random testing with Csmith found no bugs in the formally verified section (unlike in every other C compiler tested with Csmith).<p>It should be noted that the verification performed was specifically about whether the compiler would produce incorrect code; cases where it would crash or error and not produce code would not be considered errors of verification.  This would enable (for example) a coloring register allocator to be adjoined with some code that checked whether the coloring was correct and abort if not.</p>
]]></description><pubDate>Sun, 16 Aug 2026 22:42:47 +0000</pubDate><link>https://news.ycombinator.com/item?id=49324503</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49324503</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49324503</guid></item><item><title><![CDATA[New comment by pfdietz in "The Case Against Formal Verification, 50 Years Later"]]></title><description><![CDATA[
<p>> We didn't have enough compute back then.<p>The problem here is that more compute also helps testing.  So it's not clear verification will pull ahead over just doing more testing, especially if there's <i>any</i> manual part of the verification workflow.  The bugs that remain after testing become more and more difficult to stimulate.<p>> That's a test for the test suite - you make some random change to the program and see if the test suite catches it. Fuzzing is related to that concept.<p>Mutation testing is kind of orthogonal to random input testing or fuzzing.  In fact, one can use the latter to automatically kill mutants in the former, which is very useful in automatically constructing enhanced test suites.  You still need to determine what the correct behavior is for each new test input.</p>
]]></description><pubDate>Sun, 16 Aug 2026 22:06:29 +0000</pubDate><link>https://news.ycombinator.com/item?id=49324206</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49324206</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49324206</guid></item><item><title><![CDATA[New comment by pfdietz in "Superconducting monolayer cuprate with a single CuO2 plane"]]></title><description><![CDATA[
<p>The material is doped by varying the overall oxidation state of the copper, which is balanced by the number of oxygen ions.</p>
]]></description><pubDate>Sun, 16 Aug 2026 14:14:57 +0000</pubDate><link>https://news.ycombinator.com/item?id=49320300</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49320300</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49320300</guid></item><item><title><![CDATA[New comment by pfdietz in "How Gödel's Proof Works (2020)"]]></title><description><![CDATA[
<p>> Paradox is a statement that can't be proved true or false<p>No it isn't.<p>> execution of a Turing machine can't be expressed as a Gödel number<p>Yes it can.</p>
]]></description><pubDate>Sat, 15 Aug 2026 23:12:15 +0000</pubDate><link>https://news.ycombinator.com/item?id=49315164</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49315164</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49315164</guid></item><item><title><![CDATA[New comment by pfdietz in "AI has access to a vastly larger working memory than the human brain"]]></title><description><![CDATA[
<p>Obviously actual intelligence has an ineffable essential aspect, just like unicorn farts do.</p>
]]></description><pubDate>Sat, 15 Aug 2026 19:53:43 +0000</pubDate><link>https://news.ycombinator.com/item?id=49313729</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49313729</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49313729</guid></item><item><title><![CDATA[New comment by pfdietz in "AI has access to a vastly larger working memory than the human brain"]]></title><description><![CDATA[
<p>> The entire point of writing proofs is for advancing human understanding.<p>Proofs also enable AIs to direct search and generate knowledge.  Verifiability is immensely useful for keeping AI grounded.<p>One might imagine AI generating enormous numbers of hypotheses and then trying to prove or disprove them, and then mine that data for new abstractions and heuristics.</p>
]]></description><pubDate>Sat, 15 Aug 2026 19:23:43 +0000</pubDate><link>https://news.ycombinator.com/item?id=49313454</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49313454</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49313454</guid></item><item><title><![CDATA[New comment by pfdietz in "Secondhand book sales are booming. Is it because of AI?"]]></title><description><![CDATA[
<p>Your prissy outrage isn't a convincing argument that they are doing anything wrong.<p>Books are lumps of cellulose carrying information.  Destruction of excess copies is no more outrageous than discarding excess packets off the internet.</p>
]]></description><pubDate>Sat, 15 Aug 2026 15:31:01 +0000</pubDate><link>https://news.ycombinator.com/item?id=49311432</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49311432</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49311432</guid></item><item><title><![CDATA[New comment by pfdietz in "How Gödel's Proof Works (2020)"]]></title><description><![CDATA[
<p>How is that a paradox?  And how does that imply the correct argument I gave doesn't work?  (It doesn't imply that.)</p>
]]></description><pubDate>Sat, 15 Aug 2026 11:07:48 +0000</pubDate><link>https://news.ycombinator.com/item?id=49309598</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49309598</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49309598</guid></item><item><title><![CDATA[New comment by pfdietz in "How Gödel's Proof Works (2020)"]]></title><description><![CDATA[
<p>Your word salad is not even wrong.  For example:<p>> Gödel number encodes a paradox<p>WTF do you mean by this?</p>
]]></description><pubDate>Fri, 14 Aug 2026 14:02:34 +0000</pubDate><link>https://news.ycombinator.com/item?id=49298827</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49298827</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49298827</guid></item><item><title><![CDATA[New comment by pfdietz in "How Gödel's Proof Works (2020)"]]></title><description><![CDATA[
<p>You can also obtain incompleteness from the unsolvability of the halting problem, by noting that if every statement in (say) Peano arithmetic were provable, one could solve the halting problem.  Encode a halting execution of a TM as an integer using Gödel numbers and write a statement that the execution halts.  Either that statement or its negation would be provable, so search for proofs for each at the same time.<p>An additional related theorem is Rogers' recursion theorem, which is how we get programs that, when run, print their own source code (by the theorem this can be done in any Turing complete programming language.)</p>
]]></description><pubDate>Thu, 13 Aug 2026 21:49:39 +0000</pubDate><link>https://news.ycombinator.com/item?id=49292288</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49292288</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49292288</guid></item><item><title><![CDATA[New comment by pfdietz in "Tail-call optimization in C is relatively recent (2025)"]]></title><description><![CDATA[
<p>Theory says radix sort on a set of strings runs in time linear in the sum of the sizes of the strings.</p>
]]></description><pubDate>Thu, 13 Aug 2026 03:09:04 +0000</pubDate><link>https://news.ycombinator.com/item?id=49281367</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49281367</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49281367</guid></item><item><title><![CDATA[New comment by pfdietz in "Why Target Common Lisp for Code Generation?"]]></title><description><![CDATA[
<p>And 420 people can describe themselves as baked.</p>
]]></description><pubDate>Thu, 13 Aug 2026 01:21:47 +0000</pubDate><link>https://news.ycombinator.com/item?id=49280759</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49280759</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49280759</guid></item><item><title><![CDATA[New comment by pfdietz in "Tail-call optimization in C is relatively recent (2025)"]]></title><description><![CDATA[
<p>By "in practice" do you mean with one-implementation languages?<p>If there's more than one implementation, there better be a standard, and it's risky to assume any behavior not specified in the standard will be shared by all implementations.<p>Even with one-implementation languages it becomes risky to assume behaviors will remain the same as the implementation evolves.</p>
]]></description><pubDate>Wed, 12 Aug 2026 16:41:20 +0000</pubDate><link>https://news.ycombinator.com/item?id=49275171</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49275171</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49275171</guid></item><item><title><![CDATA[New comment by pfdietz in "Radical Study Suggests Life on Earth Arose Twice"]]></title><description><![CDATA[
<p>There is no need for an organized, unified project for life to spread across the galaxy, any more than there's a need for a unified effort for bacteria and fungi to consume some tasty organic matter, or for humans to have spread across Earth in prehistory.</p>
]]></description><pubDate>Mon, 10 Aug 2026 16:43:00 +0000</pubDate><link>https://news.ycombinator.com/item?id=49246169</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49246169</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49246169</guid></item><item><title><![CDATA[New comment by pfdietz in "OpenAI's new device will be hockey puck-sized and cost over $300"]]></title><description><![CDATA[
<p>And puckish.</p>
]]></description><pubDate>Mon, 10 Aug 2026 16:00:00 +0000</pubDate><link>https://news.ycombinator.com/item?id=49245447</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49245447</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49245447</guid></item><item><title><![CDATA[New comment by pfdietz in "Radical Study Suggests Life on Earth Arose Twice"]]></title><description><![CDATA[
<p>If I were saying we were <i>definitely</i> rare or unique, you'd have an argument.<p>But I'm not doing that -- I'm saying it's a possibility that is consistent with evidence.<p>The claim that life <i>is</i> common is different.  For that, you really need to present an argument that life being uncommon is ruled out.<p>In your last sentence there you've retreated from "life is common" to "it's plausible life is common".   Sure (within the constraints of the Fermi Argument, but that has uncertainties.)</p>
]]></description><pubDate>Mon, 10 Aug 2026 15:43:36 +0000</pubDate><link>https://news.ycombinator.com/item?id=49245164</link><dc:creator>pfdietz</dc:creator><comments>https://news.ycombinator.com/item?id=49245164</comments><guid isPermaLink="false">https://news.ycombinator.com/item?id=49245164</guid></item></channel></rss>