Cool new way to see zero divided by zero!

So we learned in school that if you ask what 0/0 is you have to say: undefined or you are not allowed to do that! That’s illegal!. Officially that is correct but it is also kind of boring. Like if you are allowed to take the root of negative numbers, surely you divide by zero?

I’m reading a really charming book called Shape which I highly recommend. When I read books I always have the feeling that you get to know the author. It’s like climbing in the auther’s head. Sometimes I cannot continue the book because I can’t stand the author because certain views or so. Anyway, this author is really nice it seems through his book.

But back to dividing by zero. So if you talk about it in a specific example, i.e. you add information, you could define it! For example if we talk about the ratio of conversion rate between fahrenheit en celsius, you have to divide both numbers. E.g. 98/37 = around 2.4. That is the conversion rate. But this should always be the same, so 0/0 is 2.4 in this case. He also uses the example of area to perimeter for a square. For a square with length 1 it is 1 / 4 = 0.25. If you make the square smaller the ratio will go to zero, so that would mean that an appropriate answer in this case for 0/0 would be 0!

Good luck or bad luck?

Once upon a time, there was an old man in China who had one horse and one son. One day, the horse wandered away and was lost. Upon learning this, the neighbours went to the old man and told him they were sorry to hear about his bad luck.

“How do you know it is bad luck?” he asked.

Soon thereafter, the horse returned, and brought back with him many wild horses. Upon learning this, the neighbors again went to the old man, this time congratulating him on his good luck.

“How do you know it is good luck?” he asked.

Having so many horses, the son took to riding, and it so happened that he was thrown from a horse and broke his leg. Once again, the neighbours went to the old man, this time expressing sorrow at his bad luck.

“How do you know it is bad luck?” he asked.

Soon thereafter, a war broke out and the old man’s son, because of the injury, did not have to go to war.

Holy shit this is awesome!

Beautiful image of the innate vs adaptive immune response

Did the adaptive immune system ‘evolve’ out of natural killer cells?

Why a photon always has to bend when passing an electron, or why boats seem to float.

Water on the road!!

We all have seen the mirage effect or Fata Morgana.

It seems like there are water puddles on the road, or that the car is floating. But you are actually seeing the sky instead of the road. The reason is that light rays bend in the air because of the concentration gradient. In this case because the road became hot from the sun which makes the air just above the road lower in density. Because of the gradient in density the light diffracts or bends.

Nice explanation.

The opposite effect happens on the sea with boats as you can see:

Floating boat!!

We see the boat in the air because of the bending of light. See this diagram from wikipedia:

By Brocken Inaglory, CC BY-SA 3.0, https://commons.wikimedia.org/w/index.php?curid=17769693

All of the above is the same as simple refraction, but then with a continous gradient.

Simple refraction we learned in high school

So imagine a photon passing an electron/or electron cloud.

Nice Paint skills right?

Because of the probability gradient the photon could deflect or difract just like the mirage and bend around the electron. Obviously this effect is miniscule but I guess it has to be there. It almost is as if there is a force between the photon and the electron, like gravity. Maybe if you scale it up it is the origin of gravity! I wonder if there is experimental evidence of this deflection, in theory this interaction can arise between any particle I guess.

The first 20 seconds of this song is extremely good

Idealism – last time

Sounds so nostalgic.

Possible relation why obese patients get worse COVID

Adipocytes excrete inflammatory cytokines, for example Interleukin-6. An obese patient has way higher IL-6 and other inflammatory cytokines; in which case SARS-CoV-2 infection will result in a worse cytokine storm.

A therapeutic suggestion would be to give above certain BMI already anti-inflammatory/anti-IL antibodies before a bad respiratory distress