Ciro Santilli @cirosantilli 35

Previously called "Lending Library" it seems: help.archive.org/hc/en-us/articles/360016554912-Borrowing-From-The-Lending-Library

You can borrow online books from them for a few hours/days: help.archive.org/hc/en-us/articles/360016554912-Borrowing-From-The-Lending-Library This is the most amazing thing ever made!!! You can even link to specific pages, e.g. archive.org/details/supermenstory00murr/page/80/mode/2up

They seem to a have a separate URL with the same content as well for some reason: openlibrary.org/, classic messy Internet Archive style.

Bastards are suing them www.theverge.com/2020/6/1/21277036/internet-archive-publishers-lawsuit-open-library-ebook-lending: Hachette, Penguin Random House, Wiley, and HarperCollins

It is quite hard to decide if an upload is from the official legal lending library, or just some illegal upload, e.g.:so the URLs are basically the same style. Some legality indicators:

The elliptic curve group of all elliptic curve over the rational numbers is always a finitely generated group.

The number of points may be either finite or infinite. But when infinite, it is still a finitely generated group.

For this reason, the rank of an elliptic curve over the rational numbers is always defined.

TODO example.

The relatively large Sainsbury's located at 42-45 Sidney St, Cambridge CB2 3HX. Existed in late 2010's and early 2020's Ciro Santilli witnessed.

Being the only relatively large grocery shop in central Cambridge near several colleges, where manu students live, makes this one of the most popular grocery shopping location for many of the students.

The Oxford equivalent has to be the Tesco Express on Magdalen St, Oxford OX1 3AD, but not sure if there's a name for it.

Bibliography:

Ciro Santilli believes it generally hurts more than it helps.

Especially when you can't even mention censored things to criticize them. You have to pretend they never existed. So people will forget about them, and do them again in the future.

And when companies do it just to look good, even though it has absolutely no real impact on the lives of those who are discriminated against.

See: cirosantilli.com/china-dictatorship/censorship-of-politically-incorrect-speech

Although it is impossible to understand without examples in mind, try to get familiar with the manuals as soon as possible.

Intel describes paging in the Intel Manual Volume 3 System Programming Guide - 325384-056US September 2015 Chapter 4 "Paging".

Specially interesting is Figure 4-4 "Formats of CR3 and Paging-Structure Entries with 32-Bit Paging", which gives the key data structures.

Suppose that a rod has is length $L$ measured on a rest frame $S$ (or maybe even better: two identical rulers were manufactured, and one is taken on a spaceship, a bit like the twin paradox).

Question: what is the length $L^{\prime }$ than an observer in frame $S^{\prime }$ moving relative to $S$ as speed $v$ observe the rod to be?

The key idea is that there are two events to consider in each frame, which we call 1 and 2:Note that what you visually observe on a photograph is a different measurement to the more precise/easy to calculate two event measurement. On a photograph, it seems you might not even see the contraction in some cases as mentioned at en.wikipedia.org/wiki/Terrell_rotation

Measuring a length means to measure the $x_2-x_1$ difference for a single point in time in your frame ($t2=t1$).

So what we want to obtain is $x_2^{\prime }-x_1^{\prime }$ for any given time $t^{\prime }2=t^{\prime }1$.

In summary, we have:

By plugging those values into the Lorentz transformation, we can eliminate $t_{2}and{t}_1$, and conclude that for any $t_2^{\prime }=t_1^{\prime }$, the length contraction relation holds:

The key question that needs intuitive clarification then is: but how can this be symmetric? How can both observers see each other's rulers shrink?

And the key answer is: because to the second observer, the measurements made by the first observer are not simultaneous. Notably, the two measurement events are obviously spacelike-separated events by looking at the light cone, and therefore can be measured even in different orders by different observers.

Ciro Santilli is old enough to remember his parents whispering its name with a respectful tone.

Genius: Richard Feynman and Modern Physics by James Gleick (1994) mentions several times how Richard Feynman was a reader of the encyclopedia. E.g. in youtu.be/ivxkd98mDvc?t=50 Richard's sister also talks about it.

Then the Internet came along and killed it.

The motivation model for collaborators was simple: to get famous. To be able to be selected contribute an article meant that you knew something or two! There was some physicist Ciro read the biography of who was really glad to be able to write an article on the encyclopedia after having worshiped it for so long, TODO find the reference.

While this is somewhat a part of Wikipedia motivation, it is much less so because there is no single article authorship. This is something OurBigBook.com aims to improve.

Kudos for being a not-for-profit. Also, anyone can create content: e-learning websites must allow students to create learning content. Oh, but TODO is possible for anyone to make content publicly visible? Course join links lik: www.khanacademy.org/join/MJZ6NSV7 require login. webapps.stackexchange.com/questions/165132/how-to-create-a-course-that-is-publicly-visible-without-the-need-to-login-on-kha If that's the case, it is a fatal flaw not shared by OurBigBook.com.

Another cool aspect is that they have the "physical world teacher pull student accounts in" approach built-in quite well at course creation. This is a very good feature.

As of 2021 they were a bit struggling for money it seems: www.youtube.com/watch?v=I8XdUy-wyyM?

What an awesome list the dude compiled. Contains many of the features we care the most about of the sky, since of course, apparent magnitude is a big determinant of that.