Quantum entanglement by Ciro Santilli 37 Updated +Created
Quantum entanglement is often called spooky/surprising/unintuitive, but they key question is to understand why.
To understand that, you have to understand why it is fundamentally impossible for the entangled particle pair be in a predefined state according to experiments done e.g. where one is deterministically yes and the other deterministically down.
In other words, why local hidden-variable theory is not valid.
How to generate entangled particles:
Video 1.
Bell's Theorem: The Quantum Venn Diagram Paradox by minutephysics (2017)
Source.
Contains the clearest Bell test experiment description seen so far.
It clearly describes the photon-based 22.5, 45 degree/85%/15% probability photon polarization experiment and its result conceptually.
It does not mention spontaneous parametric down-conversion but that's what they likely hint at.
Done in Collaboration with 3Blue1Brown.
Video 2.
Bell's Inequality I by ViaScience (2014)
Source.
Video 3.
Quantum Entanglement & Spooky Action at a Distance by Veritasium (2015)
Source. Gives a clear explanation of a thought Bell test experiments with electron spin of electron pairs from photon decay with three 120-degree separated slits. The downside is that he does not clearly describe an experimental setup, it is quite generic.
Video 4.
Quantum Mechanics: Animation explaining quantum physics by Physics Videos by Eugene Khutoryansky (2013)
Source. Usual Eugene, good animations, and not too precise explanations :-) youtu.be/iVpXrbZ4bnU?t=922 describes a conceptual spin entangled electron-positron pair production Stern-Gerlach experiment as a Bell test experiments. The 85% is mentioned, but not explained at all.
Video 5.
Quantum Entanglement: Spooky Action at a Distance by Don Lincoln (2020)
Source. This only has two merits compared to Video 3. "Quantum Entanglement & Spooky Action at a Distance by Veritasium (2015)": it mentions the Aspect et al. (1982) Bell test experiment, and it shows the continuous curve similar to en.wikipedia.org/wiki/File:Bell.svg. But it just does not clearly explain the bell test.
Video 6.
Quantum Entanglement Lab by Scientific American (2013)
Source. The hosts interview Professor Enrique Galvez of Colgate University who shows briefly the optical table setup without great details, and then moves to a whiteboard explanation. Treats the audience as stupid, doesn't say the keywords spontaneous parametric down-conversion and Bell's theorem which they clearly allude to. You can even them showing a two second footage of the professor explaining the rotation experiments and the data for it, but that's all you get.
Polonium isotope by Ciro Santilli 37 Updated +Created
There are no stable isotopes.
Looking Glass Universe by Ciro Santilli 37 Updated +Created
Cute simple paper-cut stop motion animations videos by Mithuna Yoganathan, a PhD in theoretical physics at the University of Cambridge: www.damtp.cam.ac.uk/person/my332.
This has the seeds of direct good intuition, but often stops a bit too short. Worth a look though, there is value in them for beginners.
There is value in tutorials written by early pioneers of the field by Ciro Santilli 37 Updated +Created
Everyone is beginner when the field is new, and there is value in tutorials written by beginners.
For example, Ciro Santilli felt it shocking how direct and satisfying Richard Feynman's scientific vulgarization of quantum electrodynamics were, e.g. at: Richard Feynman Quantum Electrodynamics Lecture at University of Auckland (1979), and that if he had just assumed minimal knowledge of mathematics, he was about to give a full satisfactory picture in just a few hours.
Other supporters of this:
Last universal common ancestor by Ciro Santilli 37 Updated +Created
Antimicrobial by Ciro Santilli 37 Updated +Created
Partial index partial derivative notation by Ciro Santilli 37 Updated +Created
This notation is not so common in basic mathematics, but it is so incredibly convenient, especially with Einstein notation as shown at Section "Einstein notation for partial derivatives":
This notation is similar to partial label partial derivative notation, but it uses indices instead of labels such as , , etc.
Read-modify-write by Ciro Santilli 37 Updated +Created
That's what usually fucks up parallel programs.
OurBigBook.com / Action plan by Ciro Santilli 37 Updated +Created
The steps are sorted in roughly chronological order. The project might fail at any point, and some steps may be carried in parallel:
  • make OurBigBook Markup good enough, to the point that it allows to create a static version of the website, which is used to prototype certain ideas, and for Ciro to start writing test content.
    Status March 2022: reached a point that it is already highly usable. The following website may continue.
  • create a basic implementation of the website, without advanced features like PageRank sorting and WYSIWYG. This is not much more than a blog with some extra metadata, so it is definitely achievable with constrained resources.
  • find a university teacher would would like to try it out.
    Ciro would like to volunteer to work for free for this teacher and students to help the students learn.
    He would like act like a "super student" who has a lot of free time and motivation.
    Ciro would start by mapping the headers of the lecture notes onto the website, and then slowly adding content as he feels the need to improve certain explanations.
    Finding teachers willing to allow this will be a major roadblock: how to convince teachers to use CC BY-SA.
    If such enlightened teacher is found, it will allow for the initial validation of the website, to decide what kind of tweaking the idea might need, and start uploading quality technical content to the site.
  • once some level of validation as been done, Ciro will start looking for charitable charitable grant opportunities more aggressively
  • if things seem to be working, start adding more advance features: PageRank-like ranking sorting and WYSIWYG editing
    The recommendation algorithms notably is left for a second stage because it needs real world data to be tested. And at the beginning, before Eternal September kicks in, there would be few posts written by well educated university students, so a simple sort by upvote would likely be good enough.
Ciro decided to start with a decent markup language with a decent implementation: OurBigBook Markup. Once that gets reasonable, he will move on to another attempt at the website itself.
The project description was originally at: github.com/cirosantilli/write-free-science-books-to-get-famous-website but being migrated here. The original working project name was "Write free books to get famous website", until Ciro decided to settle for OurBigBook.com and fixed the domain name.
Orthonormality by Ciro Santilli 37 Updated +Created
Radioactive decay by Ciro Santilli 37 Updated +Created
Ciro Santilli finds it interesting that radioactive decay basically kickstarted the domain of nuclear physics by essentially providing a natural particle accelerator from a chunk of radioactive element.
The discovery process was particularly interesting, including Henri Becquerel's luck while observing phosphorescence, and Marie Curie's observation that the uranium ore were more radioactive than pure uranium, and must therefore contain other even more radioactive substances, which lead to the discovery of polonium (half-life 138 days) and radium (half-life 1600 years).

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