Today I Learned #4: Somewhere, something incredible is waiting to be known.

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It's clearly jewellery of some description: perhaps a brooch.
 
Am I crazy or does Justinian I of the Byzantium have a duck on his right shoulder?

I've looked around, but nobody seems to ever talk about it.

Here is another one @3:54


I get it though.
The duck is the only animal that operates with total superiority on land, air, and water.
Found this with google:

1670586927798.png


The woven emblem on the right isn't the one Justinian has in the mosaics/other, but shows that such decorative images of birds were common.

 
Memory of how he met Theodora? (And so a swan, rather than a duck)
 
What would be the symbology of swans and ducks, The Poster?
 
That's for you to Google.
 
going around tumblr collecting pictures and so on . Was challenged or whatever to read Howard (who created Conan) provided only the name to Red Sonja while it was some other heroine by a different author that forms the basis of the comics character . The same tumblr source a while later also "found" a letter to Howard as it turns out the different author was a woman who was a colleague and close friend of Howard , saying she was greatly impressed by a story Howard wrote about a swordswoman . Which means ı should be looking out for a story where the Hyrkanian arrives in some hostile city wearing gold and silver tiles over what Medieval Ottoman sources used to refer as blue iron . And not a metal clad bikini to distract . Picture choice ? What , scantily clad women here ? Tumblr can be interestin' ...

10-12-2022b.jpg
 
Need a break from thinking about the potential insights resulting from the value of the natural logarithm as the enabler of getting infinitely many derivatives? (talking to myself). Then TYL about a very serene equality in the equilateral triangle ^^

1671021896029.png

Which is actually quite useful, and not just due to its simplicity. For example, you can use the "any points inside the triangle" to stand for other things, such as "any distance from a (twice) mirrored line" ^^
 
Til: No need to wonder again if your starting position is inside or outside a (no exit) labyrinth.

1671322330442.png

If a line linking it to any outside point, has an even number of cuts to the curve, you are not trapped inside.
Also cool that the intermediate value theorem takes full effect: you can't just count going through a "single point" corner inside the labyrinth as a "1 cut"; it always is 2 (if you are near a corner, you are passing its curve twice)
 
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TIL that the bird called the Bar Tailed Godwit is capable of traveling from Alaska to Tasmania non-stop.

Wikipedia Link
In 2022, a godwit numbered 234684 left Alaska on 13 October and flew non-stop to Tasmania, the first time a tagged bird has flown this route. It flew a minimum of 13,560 km (8,430 mi) in 11 days 1 hour: a record non-stop distance.
 
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I was reminded of this today:

‘Like walking on missiles’: US airman recalls the horror of the Vietnam ‘Christmas bombings’ 50 years on​

By Brad Lendon, CNN
Published 7:09 PM EST, Sat December 17, 2022

CNN —
It was one of the heaviest bombardments in history. A shock-and-awe campaign of overwhelming air power aimed at bombing into submission a determined opponent that, despite being vastly outgunned, had withstood everything the world’s most formidable war machine could throw at it.

 
tactical air in Vietnam at times had it much worse ...
 
I was reminded of this today:
‘We bombed the North Vietnamese into accepting our concessions’​

is a succint summation of all of Kissinger's foreign policy ‘brilliancy’.
 
A new Til ^^
Computers (including calculators) don't do it that way, of course, but if you want to you can always calculate the (eg) square root of something by using an approximation based on derivatives.
For example, if you wished to find the square root of 17, with a few decimals, you can start with the square root of 16 (4) and use the function for square root (f(x)=sqrx), then take its derivative (it's 1/2 1/sqrx) which for the nearest number to 17, 16, would amount to 1/8. This means the inclination from 16 to 17 is roughly +1 y for every 8 x, so for 1 x it would roughly be 1/8 => sqr17 is apprοximately 4.125 (closer to 4.123 in reality, but a good approximation).
I am sure there are ways to finesse the approximation, eg through taking the average inclination between 16 and something a little over 17 (but not between 16 and 18, that will still be off by around 0.02, just to the other side).

@Samson : what (for computers) algorithm is used for the square roots? I suppose something tied to the root division (which isn't really for humans, but it's just perfect for machines :D )
 
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A new Til ^^
Computers (including calculators) don't do it that way, of course, but if you want to you can always calculate the (eg) square root of something by using an approximation based on derivatives.
For example, if you wished to find the square root of 17, with a few decimals, you can start with the square root of 16 (4) and use the function for square root (f(x)=sqrx), then take its derivative (it's 1/2 1/sqrx) which for the nearest number to 17, 16, would amount to 1/8. This means the inclination from 16 to 17 is roughly +1 y for every 8 x, so for 1 x it would roughly be 1/8 => sqr17 is appriximately 4.125 (closer to 4.123 in reality, but a good approximation).
I am sure there are ways to finesse the approximation, eg through taking the average inclination between 16 and something a little over 17 (but not between 16 and 18, that will still be off by around 0.02, just to the other side).

@Samson : what (for computers) algorithm is used for the square roots? I suppose something tied to the root division (which isn't really for humans, but it's just perfect for machines :D )
I do not actually know, but there is a famous approximation for inverse square root (
080a33b7fb940dfde4d893093e55096f6bf149dc
) that was implemented to make the graphics faster in Quake. It does not look like it should work, but it does. Here is the code with the comments sanitised, see wikipedia for the original comments that are appropriate for the code if not for CFC.

C:
    float InvSqrt(float x){
        float xhalf = 0.5f * x;
        int i = *(int*)&x;            // store floating-point bits in integer
        i = 0x5f3759df - (i >> 1);    // initial guess for Newton's method
        x = *(float*)&i;              // convert new bits into float
        x = x*(1.5f - xhalf*x*x);     // One round of Newton's method
        return x;
    }
 
Today I learned that Germany has a "Federal Ministry of Transport and Digital Infrastructure," which seems like two odd things to combine together. Also, they may provide funding for video games.
 
one side builds roads , the other side lays the wires for the internet using the same machines . ı guess .
 
Right of way issues!
 
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