Hacker News: spekcular

Chlormequat in food and urine from adults in the United States from 2017 to 2023

spekcular — Thu, 15 Feb 2024 15:22:36 +0000

Article URL: https://www.nature.com/articles/s41370-024-00643-4

Comments URL: https://news.ycombinator.com/item?id=39383739

Points: 92

# Comments: 74

Making every researcher seek grants is a broken model

spekcular — Mon, 05 Feb 2024 19:06:49 +0000

Article URL: https://rootsofprogress.org/the-block-funding-model-for-science

Comments URL: https://news.ycombinator.com/item?id=39265495

Points: 3

# Comments: 0

A new Lean formalization project for the Prime Number Theorem

spekcular — Sun, 04 Feb 2024 23:07:41 +0000

Article URL: https://mathstodon.xyz/@tao/111847680248482955

Comments URL: https://news.ycombinator.com/item?id=39255479

Points: 1

# Comments: 0

Lean in 2024

spekcular — Tue, 23 Jan 2024 02:05:12 +0000

Article URL: https://xenaproject.wordpress.com/2024/01/20/lean-in-2024/

Comments URL: https://news.ycombinator.com/item?id=39098598

Points: 2

# Comments: 0

New comment by spekcular in "Julia 1.10"

spekcular — Thu, 28 Dec 2023 18:02:22 +0000

Is the "optimal Julia workflow" written down anywhere?

You Should Be Working on Hardware

spekcular — Sat, 26 Aug 2023 20:21:40 +0000

Article URL: https://caseyhandmer.wordpress.com/2023/08/25/you-should-be-working-on-hardware/

Comments URL: https://news.ycombinator.com/item?id=37276518

Points: 12

# Comments: 6

An Old Conjecture Falls, Making Spheres a Lot More Complicated

spekcular — Tue, 22 Aug 2023 21:34:51 +0000

Article URL: https://www.quantamagazine.org/an-old-conjecture-falls-making-spheres-a-lot-more-complicated-20230822/

Comments URL: https://news.ycombinator.com/item?id=37228822

Points: 129

# Comments: 80

Absence of superconductivity in LK-99 at ambient conditions

spekcular — Tue, 08 Aug 2023 01:12:23 +0000

Article URL: https://arxiv.org/abs/2308.03544

Comments URL: https://news.ycombinator.com/item?id=37043196

Points: 142

# Comments: 75

New comment by spekcular in "The Dome: A simple violation of determinism in Newtonian mechanics (2005)"

spekcular — Sat, 05 Aug 2023 16:38:19 +0000

You may be interested to know that this exact objection has been made in the philosophical literature. See "Causal Fundamentalism in Physics" by Zinkernagel (2010). Available here: https://philsci-archive.pitt.edu/4690/1/CausalFundam.pdf

At the end, the author notes (as you do) that if you consider a finite difference equation with small time steps, there are no pathological solutions. He also mentions that Newton takes this difference equation approach when solving problems in his Principia.

See also "The Norton Dome and the Nineteenth Century Foundations of Determinism" by van Strien:

>> Abstract. The recent discovery of an indeterministic system in classical mechanics, the Norton dome, has shown that answering the question whether classical mechanics is deterministic can be a complicated matter. In this paper I show that indeterministic systems similar to the Norton dome were already known in the nineteenth century: I discuss four nineteenth century authors who wrote about such systems, namely Poisson, Duhamel, Boussinesq and Bertrand. However, I argue that their discussion of such systems was very different from the contemporary discussion about the Norton dome, because physicists in the nineteenth century conceived of determinism in essentially different ways: whereas in the contemporary literature on determinism in classical physics, determinism is usually taken to be a property of the equations of physics, in the nineteenth century determinism was primarily taken to be a presupposition of theories in physics, and as such it was not necessarily affected by the possible existence of systems such as the Norton dome.

Successful room temperature ambient-pressure magnetic levitation of LK-99

spekcular — Fri, 04 Aug 2023 01:15:32 +0000

Article URL: https://arxiv.org/abs/2308.01516

Comments URL: https://news.ycombinator.com/item?id=36994214

Points: 2408

# Comments: 1199

Electronic Structure of LK-99

spekcular — Wed, 02 Aug 2023 00:57:46 +0000

Article URL: https://arxiv.org/abs/2308.00676

Comments URL: https://news.ycombinator.com/item?id=36965545

Points: 551

# Comments: 432

Pb-apatite framework as a generator of possible superconductivity

spekcular — Wed, 02 Aug 2023 00:56:45 +0000

Article URL: https://arxiv.org/abs/2308.00698

Comments URL: https://news.ycombinator.com/item?id=36965537

Points: 3

# Comments: 1

Synthesis of possible room temperature superconductor LK-99

spekcular — Tue, 01 Aug 2023 01:19:43 +0000

Article URL: https://arxiv.org/abs/2307.16402

Comments URL: https://news.ycombinator.com/item?id=36951148

Points: 3

# Comments: 0

Semiconducting Transport in LK99 reproduction attempt

spekcular — Tue, 01 Aug 2023 01:18:41 +0000

Article URL: https://arxiv.org/abs/2307.16802

Comments URL: https://news.ycombinator.com/item?id=36951140

Points: 613

# Comments: 255

New comment by spekcular in "Reasons to be skeptical of that room-temperature superconductor claim"

spekcular — Wed, 26 Jul 2023 19:11:59 +0000

The author is a professor at Ohio State University, specializing in condensed matter theory. His CV list two works on superconductors and a dissertation on supercapacitors.

New comment by spekcular in "Using predictions from arbitrary models to get tighter confidence intervals"

spekcular — Mon, 08 May 2023 02:44:54 +0000

There's also a C-R bound for the biased case.

New comment by spekcular in "P < 0.05 Considered Harmful"

spekcular — Tue, 11 Apr 2023 01:57:58 +0000

But here the issue is the uncorrected multiple testing and under-reporting of results, not the p-values themselves. Any criterion for judging the presence of an effect is going to suffer from the same issue, if researchers don't pre-register and report all of their analyses (since otherwise you have censored data, "researcher degrees of freedom," and so on). This is really a a problem with the design and reporting of studies, not the analysis method.

New comment by spekcular in "P < 0.05 Considered Harmful"

spekcular — Mon, 10 Apr 2023 21:14:22 +0000

AIC is an estimate of prediction error. I would caution against using it for selecting a model for the purpose of inference of e.g. population parameters from some dataset (without producing some additional justification that this is a sensible thing to do). Also, uncertainty quantification after data-dependent model selection can be tricky.

Best practice (as I understand it) is to fix the model ahead of time, before seeing the data, if possible (as in a randomized controlled trial of a new medicine, etc.).

New comment by spekcular in "P < 0.05 Considered Harmful"

spekcular — Mon, 10 Apr 2023 19:55:22 +0000

How else do you propose to construct procedures that control type I error and evaluate their properties?

New comment by spekcular in "P < 0.05 Considered Harmful"

spekcular — Mon, 10 Apr 2023 18:05:06 +0000

I don't understand. CIs are equivalent to computing a bunch of p-values, by test-interval duality. Should I interpret your points as critiques of simple analyses that only test a single point null of no effect (and go no further)? (I would agree that is bad.)