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Today I learned

  1. Jan 30, 2017 #2001

    Nugso

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    Heh. I've actually been there.

    Also, why it isn't a TIL, I would like to ask you lot: How do you "learn" all those things? For example I learn something every day, but forget in a few days/weeks. Do you write them down too? Or just not care whether you'll remember?
     
  2. Jan 30, 2017 #2002
    If we all used spaced repetition we could remember all those facts almost forever!
     
  3. Jan 30, 2017 #2003

    Buzz Bloom

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    Hi @Nugso:
    I generally bookmark or download stuff I learn. Most of what I learn day-by-day is that I have problems understanding what I am learning. I don't post about those things as a TIL item, but very occasionally I actually come to understand something, or at least I am pretty confident that I have, and then I post about that. When I learn something I don't understand, I sometimes start a thread to seek someone who can explain it to me.

    Regards,
    Buzz
     
  4. Jan 30, 2017 #2004

    BillTre

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  5. Jan 30, 2017 #2005
    I wasn't aware fish were farters, so that's kind of a 2 for 1 deal there...

    On the other hand I'm not sure I want to remember this one.

    -Dave K
     
  6. Jan 30, 2017 #2006

    Nugso

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    Hehe, that's where Anki comes in handy I guess :)

    I see. I'm currently taking notes of what I'm learning every day such as Nuremberg Trials and hCG. Would be good to remember them forever!
     
  7. Jan 31, 2017 #2007
  8. Feb 1, 2017 #2008
    Today I learned the new word: pareidolia.
     
  9. Feb 2, 2017 #2009

    nsaspook

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    Today I learned what might be the loneliest job in the world.

    https://sputniknews.com/art_living/201702021050289083-austrian-town-loneliest-job/
     
  10. Feb 2, 2017 #2010
  11. Feb 2, 2017 #2011

    OmCheeto

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    Current temperature in Saalfelden, Austria: 34°F
    Current temperature in Tampa, Florida: 78°F

    Crawl into your refrigerator, and see how long you last.

    ps.
    Current temperature inside my refrigerator: 37.4°F
    Current temperature outside my house: 36°F (wind consistent at around 38 mph. Sorry, but I don't know the equation for wind chill, off the top of my head.)
    Nominal OmCheeto refrigerator temperature: 32.5°F (we're doing refrigerator experiments)
     
  12. Feb 2, 2017 #2012

    fresh_42

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    2017 Award

    Staff: Mentor

    The last one made it a year. Priest and therapist. He returned to Vienna.

    GetImage.ashx?fileid=1021136&mode=T&width=210&height=400.jpg

    Btw.: deadline is 2/20
     
  13. Feb 2, 2017 #2013
    Only because my wife would find me!
     
  14. Feb 2, 2017 #2014

    mfb

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    The "mission" is just from April to October/November. Temperature should be fine.
    Not sure how you get water and food there.
     
  15. Feb 7, 2017 #2015

    Buzz Bloom

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    TIL (finally after almost two years of making errors and correcting my errors) the technically correct form of the matter term in Friedmann's equation.
    Friedmann.png
    It all started with
    It is well known that this form is wrong for sufficiently small values of a for which matter particles become relativistic. For that case, matter particles behave gravitationally approximately like photons, so the term would be approximately
    (1) ΩM a-4 .​
    The form that is correct for the full range of values for a is:
    (2) ΩM a-3 × √[ 1 + Q2 × (a-2 - 1) ]​
    where Q = v/c, where v is the average speed of the particles for a=1. It should be clear that for very small values of a, Q will become close to 1, and (2) will be approximated by (1).

    I plan to start a new thread soon to hopefully get someone here at PF to check my math, and to discuss some implications.
     
    Last edited: Feb 7, 2017
  16. Feb 7, 2017 #2016

    BillTre

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    TIL:
    The U.S. Department of Agriculture (USDA) said in a statement that it revoked public access to the reports “based on our commitment to being transparent … and maintaining the privacy rights of individuals.”

    ... Inspection reports contain little, if any, personal information about individuals.
     
  17. Feb 9, 2017 #2017
    Today i learned that infinite data compression is possible
     
  18. Feb 9, 2017 #2018

    fresh_42

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    Staff: Mentor

    ... or as I call it: the WOM.
     
  19. Feb 9, 2017 #2019
    It's actually really simple
     
  20. Feb 9, 2017 #2020

    jim hardy

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  21. Feb 10, 2017 #2021
    I have learned something important from the discussion about the Doomsday Clock. I learned that I think more clearly and communicate better when I avoid satire, sarcasm, hyperbole, metaphor, simile, and figures of speech in general. I must also avoid humor, because I am not very good at it, and people usually take me seriously even when I am trying to be funny. I need to clear my thinking of the many literary techniques I learned in high school, and from the bad influence of comedy in TV and movies.

    From now on my rule is to say what I mean as clearly as I can, knowing that even then, I could fail to make my meaning clear to some. Also, I will avoid Utopian scenarios.

    For example, in an earlier post I came up with a purely fanciful scenario about Germany developing a "green weapon" that could immediately neutralize all nuclear weapons. I hope people realized it was a sort of "modest proposal" inspired by Swift. But if they did not, I blame myself.

    In an earlier scenario, I suggested the USA and Russia team up to force global nuclear disarmament. Even if this is technically possible, it is politically Utopian.

    "Nothing unreal exists" (First rule of Vulcan metaphysics.)
     
  22. Feb 10, 2017 #2022
    I've found this helpful for online argumentation, when I can get myself to comply...https://www.brainpickings.org/2014/03/28/daniel-dennett-rapoport-rules-criticism/
     
  23. Feb 10, 2017 #2023

    Buzz Bloom

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    Hi @David Reeves:

    You may like the book I am currently reading and enjoying greatly.
    Sapiens: A Brief History of Humankind by Yuval Noah Harari.​
    Here is an abbreviated quote from pp 113-116.
    Three main factors prevent people from realising that the order organizing their lives exists only in their imagination.
    a. The imagined order is embedded in the material world.
    . . .
    b. The imagined order shapes our desires.
    . . .
    c: The imagined order is inter-subjective.
    . . .​
    From my perspective the book makes very clear that a great deal of what almost everyone believes exists is unreal. Of course his meaning for "real" and exists" may differ somewhat from yours.

    Regards,
    Buzz
     
  24. Feb 10, 2017 #2024
    Today I also learned that I really need to remember to edit my posts on PF in the text editor, before I publish them, so I don't need to edit after the post has been published.
     
  25. Feb 10, 2017 #2025

    jtbell

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    Today I learned (from a PBS documentary) that up to 20% of squirrels steal their nuts from other squirrels instead of foraging for them. They watch a nut being buried, then dig it up when they think the burier is gone. But if the burier catches them in the act... now I know why they chase each other so often!
     
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