What free resources do you know on the internet that everyone should use?

Potential Category Ideas

• FOSS Software
• Quality of Life
• Public Services
• Other List of Lists
• Personal Finance
• Github Awesome Repositories
• Firefox Addons
• Free Research/Books
• Piracy Sites & Lists
• Real Life Resources

Links and Resources

• Github - Awesome
• Lemmy - What are some useful links everyone should know?
• Reddit - Mirror Post
• Wikipedia - FOSS List

What are your favorite mathematics channels/videos on YouTube?

There are tons of great videos on YT, but I'll list some resources from 3Blue1Brown's SoME3 contest if you want to discover more math explainers.

SoME3 Resources

• YouTube - 25 Math explainers you may enjoy
• YouTube - SoME3 424 Video Playlist
• 3Blue1Brown - Summer of Math Exposition (Non-videos)

This is a continuation to my original "What are the most mindblowing things in mathematics?" post.

Additional Resources

• YouTube - 3Blue1Brown Channel
• Lemmy - What are the most mindblowing things in mathematics?
• YouTube - PBS Infinite Series
• YouTube - Numberphile

It is becoming near impossible to find relevant information from search engines. Duckduckgo, SearXNG, Bing, Google, and so many more mainstream engines have a significantly high noise to signal ratio, and it is getting worse.

Here are a collection of the best search engines I know, please add more to the list.

• Forum Search Engine: https://crowdview.ai/
• Non-commercial Search: https://search.marginalia.nu/
• Libre Meta Search Engine: https://librey.devol.it/
• Golden Age Search Engine: https://www.wiby.org/
• Yandex: https://yandex.com/

If no more high quality search engines exist, would it be possible to host your own?

EDIT: Some new discoveries. The addon uBlacklist and filters can block super SEO sites from appearing in search.

• https://addons.mozilla.org/en-US/firefox/addon/ublacklist/
• https://github.com/rjaus/awesome-ublacklist
• https://github.com/NotaInutilis/Super-SEO-Spam-Suppressor

It is becoming near impossible to find relevant information from search engines. Duckduckgo, SearXNG, Bing, Google, and so many more mainstream engines have a significantly high noise to signal ratio, and it is getting worse.

Here are a collection of the best search engines I know, please add more to the list.

• Forum Search Engine: https://crowdview.ai/
• Non-commercial Search: https://search.marginalia.nu/
• Libre Meta Search Engine: https://librey.devol.it/
• Golden Age Search Engine: https://www.wiby.org/
• Yandex: https://yandex.com/

If no more high quality search engines exist, would it be possible to host your own?

EDIT: Some new discoveries. The addon uBlacklist and filters can block super SEO sites from appearing in search.

• https://addons.mozilla.org/en-US/firefox/addon/ublacklist/
• https://github.com/rjaus/awesome-ublacklist
• https://github.com/NotaInutilis/Super-SEO-Spam-Suppressor

Feel free to post multiple suggestions for different genres. For example, atmospheric, sci-fi, adventure-like, etc.

What concepts or facts do you know from math that is mind blowing, awesome, or simply fascinating?

Here are some I would like to share:

• Gödel's incompleteness theorems: There are some problems in math so difficult that it can never be solved no matter how much time you put into it.
• Halting problem: It is impossible to write a program that can figure out whether or not any input program loops forever or finishes running. (Undecidablity)

The Busy Beaver function

Now this is the mind blowing one. What is the largest non-infinite number you know? Graham's Number? TREE(3)? TREE(TREE(3))? This one will beat it easily.

• The Busy Beaver function produces the fastest growing number that is theoretically possible. These numbers are so large we don't even know if you can compute the function to get the value even with an infinitely powerful PC.
• In fact, just the mere act of being able to compute the value would mean solving the hardest problems in mathematics.
• Σ(1) = 1
• Σ(4) = 13
• Σ(6) > 10^10^10^10^10^10^10^10^10^10^10^10^10^10^10 (10s are stacked on each other)
• Σ(17) > Graham's Number
• Σ(27) If you can compute this function the Goldbach conjecture is false.
• Σ(744) If you can compute this function the Riemann hypothesis is false.

Sources:

• YouTube - The Busy Beaver function by Mutual Information
• YouTube - Gödel's incompleteness Theorem by Veritasium
• YouTube - Halting Problem by Computerphile
• YouTube - Graham's Number by Numberphile
• YouTube - TREE(3) by Numberphile
• Wikipedia - Gödel's incompleteness theorems
• Wikipedia - Halting Problem
• Wikipedia - Busy Beaver
• Wikipedia - Riemann hypothesis
• Wikipedia - Goldbach's conjecture
• Wikipedia - Millennium Prize Problems - $1,000,000 Reward for a solution

An Internet Portal is an information hub connecting you a much wider portion of the internet.

For example:

• Wikipedia's Content Portal: https://en.wikipedia.org/wiki/Wikipedia:Contents/Portals
• Github's List of Awesome: https://github.com/topics/awesome
• Wikipedia's List of list of lists: https://en.wikipedia.org/wiki/List_of_lists_of_lists
• Wikipedia Internet Forums List: https://en.wikipedia.org/wiki/List_of_Internet_forums

What Internet Portals do you know of that you would like to share?

Search engines have been dropping in quality significantly within the past decade, and especially within this past year. The noise to signal ratio has been frankly painful.

Can you please share some resources you use when trying to find answers to technical questions?

For example, STEM, academia, engineering, programming, etc.

What social media platforms do you use and want to recommend to others? Front ends could also be a suggestion, along with lists of great communities.

For example: https://sub.rehab/

Which is a collection of communities from different platforms.

The quality of search engines has gone down so much for technical questions.

I'm looking for a way to index sites like stack exchanges, reddit, quora, and research papers. Would this be possible to do this locally with metadata?

SEO has made it incredibly hard to find answers without getting spammed by news and blog sites. Places like ask Lemmy help democratize answers through upvotes and downvotes so the quality is higher.

Do you know of any hidden gems for search engines or Q&A sites that contain highly relevant answers without much noise?