Topics Top articles New articles Updated articles Top users New users New discussions Top discussions New comments+ New article
What I learned in Harvard part 1 by Jorge Paulo Lemann (2012)
Source. Portuguese talk about his experiences. A bit bably, but has a few good comments:You don't learn the Harvard experience, you absorb it.
- This one does have bias danger though. But detecting greatness, is as type of bias arguably.
Being amongst excellent people makes you learn what excelent people are like, just like only by tasting many different types of wine can you know what good wine is like.
Einstein notation for partial derivatives by 
Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01
Ciro Santilli 35 Updated 2025-01-10 +Created 1970-01-01The Einstein summation convention works will with partial derivatives and it is widely used in particle physics.
In particular, the divergence and the Laplacian can be succintly expressed in this notation:
In order to expresse partial derivatives, we must use what Ciro Santilli calls the "partial index partial derivative notation", which refers to variales with indices such as , , , , and instead of the usual letters , and .
TODO what is the point of them? Why not just sum over every index that appears twice, regardless of where it is, as mentioned at: www.maths.cam.ac.uk/postgrad/part-iii/files/misc/index-notation.pdf.
Vectors with the index on top such as are the "regular vectors", they are called covariant vectors.
Those in indices on bottom are called contravariant vectors.
It is possible to change between them by Raising and lowering indices.
The values are different only when the metric signature matrix is different from the identity matrix.
Of all the rich person foundations, this is the one that feels the most hardcore.
They put huge focus on autism. Do they have an autistic child? Yes: www.forbes.com/pictures/eilm45mll/james-simons-autism/?sh=7825234250ce his adughter.
Can represent a symmetric bilinear form as shown at matrix representation of a symmetric bilinear form, or a quadratic form.
Mahayana adds a bunch of stuff on top of the Pali Canon. Most of it appears to be random mysticism. Maybe there is something good in it... maybe.
Psalm 46:10 from the bible:
Be still, and know that I am God;
I will be exalted among the nations,
I will be exalted in the earth.
Theses places give out free food all the time.
The first time Ciro Santilli went to one was when an Indian friend of his took him to the one in the North of Paris when they were living there in the first half of the 2010's, the Gurdwara Singh Sabha France.
Much like Islam's Ramadan, Ciro Santilli appreciates this a lot due to due to Ciro Santilli's self perceived compassionate personality and Ciro Santilli's cheapness.
Instead of just talking, those people really go out, and put food on the plate for anyone who needs it (or even for those that don't really need it! Although who would be so souless to eat for free and not donate a few bucks if they can afford to???). There's a beauty to that.
Writing this also remembered Ciro of non-religious groups that would give out free food to the poor at
tx 243dea31863e94dc2f293489db02452e9bde279df1ab7feb6e456a4af672156a contains another upload script. The help reads:
Publish text in the blockchain, suitably padded for easy recovery with strings
Pinned article: ourbigbook/introduction-to-the-ourbigbook-project
Welcome to the OurBigBook Project! Our goal is to create the perfect publishing platform for STEM subjects, and get university-level students to write the best free STEM tutorials ever.
Everyone is welcome to create an account and play with the site: ourbigbook.com/go/register. We belive that students themselves can write amazing tutorials, but teachers are welcome too. You can write about anything you want, it doesn't have to be STEM or even educational. Silly test content is very welcome and you won't be penalized in any way. Just keep it legal!
We have two killer features:
- topics: topics group articles by different users with the same title, e.g. here is the topic for the "Fundamental Theorem of Calculus" ourbigbook.com/go/topic/fundamental-theorem-of-calculusArticles of different users are sorted by upvote within each article page. This feature is a bit like:
- a Wikipedia where each user can have their own version of each article
- a Q&A website like Stack Overflow, where multiple people can give their views on a given topic, and the best ones are sorted by upvote. Except you don't need to wait for someone to ask first, and any topic goes, no matter how narrow or broad
This feature makes it possible for readers to find better explanations of any topic created by other writers. And it allows writers to create an explanation in a place that readers might actually find it.
Figure 1. Screenshot of the "Derivative" topic page. View it live at: ourbigbook.com/go/topic/derivative - local editing: you can store all your personal knowledge base content locally in a plaintext markup format that can be edited locally and published either:This way you can be sure that even if OurBigBook.com were to go down one day (which we have no plans to do as it is quite cheap to host!), your content will still be perfectly readable as a static site.
- to OurBigBook.com to get awesome multi-user features like topics and likes
- as HTML files to a static website, which you can host yourself for free on many external providers like GitHub Pages, and remain in full control
Figure 2. You can publish local OurBigBook lightweight markup files to either OurBigBook.com or as a static website.
Figure 3. Visual Studio Code extension installation.
Figure 4. Visual Studio Code extension tree navigation.
Figure 5. . You can also edit articles on the Web editor without installing anything locally. Video 3. Edit locally and publish demo. Source. This shows editing OurBigBook Markup and publishing it using the Visual Studio Code extension.Video 4. OurBigBook Visual Studio Code extension editing and navigation demo. Source. - Internal cross file references done right:
- Infinitely deep tables of contents:
Figure 6. Dynamic article tree with infinitely deep table of contents.Live URL: ourbigbook.com/cirosantilli/chordateDescendant pages can also show up as toplevel e.g.: ourbigbook.com/cirosantilli/chordate-subclade
All our software is open source and hosted at: github.com/ourbigbook/ourbigbook
Further documentation can be found at: docs.ourbigbook.com
Feel free to reach our to us for any help or suggestions: docs.ourbigbook.com/#contact