📎 10 physics facts you should have learned in school but probably didn’t

1. Entropy doesn’t measure disorder, it measures likelihood.

Really the idea that entropy measures disorder is totally not helpful. Suppose I make a dough and I break an egg and dump it on the flour. I add sugar and butter and mix it until the dough is smooth. Which state is more orderly, the broken egg on flour with butter over it, or the final dough?

I’d go for the dough. But that’s the state with higher entropy. And if you opted for the egg on flour, how about oil and water? Is the entropy higher when they’re separated, or when you shake them vigorously so that they’re mixed? In this case the better sorted case has the higher entropy.

Entropy is defined as the number of “microstates” that give the same “macrostate”. Microstates contain all details about a system’s individual constituents. The macrostate on the other hand is characterized only by general information, like “separated in two layers” or “smooth on average”. There are a lot of states for the dough ingredients that will turn to dough when mixed, but very few states that will separate into eggs and flour when mixed. Hence, the dough has the higher entropy. Similar story for oil and water: Easy to unmix, hard to mix, hence the unmixed state has the higher entropy.

http://backreaction.blogspot.com/2018/07/10-physics-facts-you-should-have.html

14 November 2019

📎 the control-alt-backspace manifesto

Technology is supposed to work for people. From the lever to the Internet, tools designed by people have saved us time and energy and allowed us to accomplish things that were impractical or completely impossible before. While no technology is without its downsides, in general it is difficult to dispute that technology working for people has transformed human society for the better.

Unfortunately, sometimes people end up working for technology instead. This is a strange state of affairs, but it happens just about daily for most of us (...)

https://controlaltbackspace.org/manifesto/

20 October 2019

📎 to decarbonize we must decomputerize

Confronting the climate crisis will require something more radical than just making data greener. That’s why we should put another tactic on the table: making less data. We should reject the assumption that our built environment must become one big computer. We should erect barriers against the spread of “smartness” into all of the spaces of our lives. To decarbonize, we need to decomputerize.

https://www.notechmagazine.com/2019/10/to-decarbonize-we-must-decomputerize-why-we-need-a-luddite-revolution.html

11 October 2019

📎 hippocratic oath for STEM

1. I will never allow anyone else to make me a cog. I will never do what is stupid or horrible because “that’s what the regulations say” or “that’s what my supervisor said,” and then sleep soundly at night. I’ll never do my part for a project unless I’m satisfied that the project’s broader goals are, at worst, morally neutral. There’s no one on earth who gets to say: “I just solve technical problems. Moral implications are outside my scope.”

https://www.scottaaronson.com/blog/?p=4292 

(and the referenced article about Hannah Fry’s call)

27 September 2019

📎 quantum supremacy FAQ

You’ve seen the stories—in the Financial Times, Technology Review, CNET, Facebook, Reddit, Twitter, or elsewhere—saying that a group at Google has now achieved quantum computational supremacy with a 53-qubit superconducting device. While these stories are easy to find, I’m not going to link to them here, for the simple reason that none of them were supposed to exist yet.

https://www.scottaaronson.com/blog/?p=4317

24 September 2019

📎 into the personal-website-verse

Personal websites are called personal websites because they are just that: personal. Thus, the primary objective still is to have a place to express ourselves, to explore ourselves, a place that lasts while the daily storms pass by. A place of consideration, and yes, a place of proudly sharing what we do, what we think, and what we care about. A place to contribute your voice and help others. A home on the internet. A place to tell your story.

But on top of that, we have the chance to (re-)establish personal websites also as central elements of online discourse and as entry points for people who are new to the web community. For this, we need to find ways to create an ecosystem that lives up to the diversity of the personal-website-verse. Consequently, what will hold our sites together, is most possibly not one technology to rule them all, but a multitude of different and ever-evolving technologies. Things like hyperlinks, comments, Webmentions, and RSS, of course, but also other technologies that have yet to be invented. Not only would this leave enough room for individual preferences, but it would also make the whole construct more resilient while still being flexible enough to evolve over time.

https://matthiasott.com/articles/into-the-personal-website-verse

6 September 2019

📎 507 Mechanical Movements

This is an online edition of the classic technical reference Five Hundred and Seven Mechanical Movements by Henry T. Brown.

This site contains the original illustrations and text from the 21st edition of the book, published in 1908. It also includes animated versions of the illustrations, and occasional notes by the webmaster.

http://507movements.com/

23 May 2019