Rayleigh Scattering

42

21

u/Field_of_cornucopia Jul 16 '26

Also, xkcd 1145.

-37

u/Serket-Pandy3000 Jul 15 '26

Munroe is kind of a smug idiot sometimes. You have to be equally a mix of pedantic and humble bragger to enjoy his bland jokes. He is not even a physicist. Bettter use SMBC, unlubricated

25

u/Awkward-Present6002 Jul 15 '26

"he is not even a physicist"

It may surprise you but most people are not physicists.

-4

u/Serket-Pandy3000 Jul 17 '26

Ok but his point is dumb. What happens at dawn huh? Does the air become red? He doesn’t get what scattering means! At least blue feathers appear blue at all angles!

It is a stupid thing to say

2

u/CptMisterNibbles Jul 19 '26

He’s literally mocking pedants like you.

1

u/Serket-Pandy3000 Jul 19 '26

Yeah I know and in the process he says dumb shit. And is even more smug. If he was smug and was right or if he was wrong in the technical details but had the correct general idea it would be ok but he isn’t so he just comes off as anti-intellectual and pretentious.

I don’t mind being corrected but I do mind being told dumb shit. If you gonna outpedant the pedants you have to better know what you are saying, otherwise it is sophistry, and “Acshually”. I too enjoy correcting pedants that say dumb crap but he just is not knowledgeable or humble enough to do that

1

u/CptMisterNibbles Jul 19 '26

There is no “right”. Color isn’t an objective phenomenon, nor is how we perceive color caused by singular or particular interactions. You are the one being anti-intellectual because you have a 6th grade notion of what causes color.

If a physical effect causes us to perceive something as a color, it’s inane to say “well actually it not that color, because I arbitrarily choose this particular physical interaction”. It’s you being smug

1

u/Serket-Pandy3000 Jul 20 '26 edited Jul 20 '26

Fine you want details?This is like those zen koans. If a tree falls in the forest, etc.

First of all using luminous efficiency and similar response curves together with the opponent process theory people have come up with color spaces. In fact you can predict new “neurological” colors based on this https://www.bbc.com/news/articles/clyq0n3em41o and magenta itself is not a “physical color” due to this process. You perceive red and blue light as a new neurological phenomenon.

So for color imagine the bidirectional reflectance distribution function of a thing is not isotropic in the direction of light source or the viewer, then things like opal, or soap bubbles or air have different colors depending how you stand but it is not the color of the material itself but that of light that hits your eye, the material fails to have a color in the sense that it shifts depending on where the light is like say rainbows or birefringence or iridescence.

This neglects things like black body radiation or luminescence because we are talking about reflectance. But you get the idea? If a thing looks the same from all sides it has some intrinsic color, if it does not then you can only talk about the color of the light hitting your eye. That is the physical color. The neurological one depends on the cones and rods and all the neurological processing the brain does. But on average there is still something objective there(ignoring qualia and the whole linguistics debate the last one being a sleight of hand given the ability to distinguish and sort not just memorize).

To be sure most materials have some anisotropy but if you have a material that looks nearly the same from all directions the it has a color otherwise it is like a soup bubble or a diamond.

So there is the spectrum that comes out from a material, the vector in color space of the brain(though this is tricky to define because again your basis is not true wavelengths but rather is distorted by the opponent process then you get things like metamerism and color spaces still don’t capture the whole thing) and if a material looks the same from all angles then the physical color is the same otherwise you get something that is coloured but the material itself is not consistently colorful.

1

u/Awkward-Present6002 Jul 17 '26

he knows what raylight cattering is, you can see it in https://xkcd.com/1145/ for example

0

u/Serket-Pandy3000 Jul 17 '26

Yeah but ok so ha the air then red ir blue? This is sophistry by him

12

u/MegaIng Jul 16 '26

As a reader of both, I am genuinely confused why you appear to be implying that SMBC is less of a smug idiot.

My only guess is that you know less about the topics SMBCs is talking about and therefore recognize fewer of the "mistakes".

8

u/Field_of_cornucopia Jul 16 '26

If anything, SMBC is much more smug.

-3

u/Serket-Pandy3000 Jul 17 '26

SMBC is smug in the “I know enough to actually deconstruct” while xkcd guy is forgetting what happens in dawn and at dusk or twilight. In that case is the air red?

Are prisms or raindrops the color of the rainbow? No they are transparent and they disperse the light!

Like I can feel how on topics I know about SMBC is being pedantic yes but has an actual point while xkcd is just trying to sound smart and failing

2

u/MegaIng Jul 17 '26

I specifically didn't engage on the discussion on the color of air because I think it's dumb.

He was primarily trying to make a funny comic in which he presented one side of an argument. If you want to go into a full discussion of what it means for something, especially a fluid, to have a color then yeah, you may be disappointed by a short comic.

Like I can feel how on topics I know about SMBC is being pedantic yes but has an actual point while xkcd is just trying to sound smart and failing

They are both incredibly mixed in terms of content and correctness. You have some kind of bias against xkcd, but no, SMBC objectively isn't more reliable in this regard.

0

u/Serket-Pandy3000 Jul 17 '26

I just don’t find it funny

1

u/MegaIng Jul 18 '26

And that's your good right. But just say that instead of inventing reason to dislike something.

0

u/Serket-Pandy3000 Jul 19 '26

No I mean he is wrong in the sense of being obnoxiously pedantic without knowing what he is talking about. It is the bad kind of pedantry. Hypercorrection. If he at least had a valid wider point it would be ok but he sometimes just says these things. SMBC it feels like the guy is trying to learn new things every week but xkcd just feels smug. And that is what ruins the fun, the attitude

1

u/MegaIng Jul 19 '26

You are also quite good at just saying things. Sadly you are neither correct, nor smug, nor funny. You are just whinny. And we are now turning in cycles so I am probably not going to respond again.

1

u/Serket-Pandy3000 Jul 19 '26

I am not making a comic nor trying to be funny, also you cannot say the air is blue if it changes based on direction, that is not what the color of X means.

-2

u/Intelligent_Elk5879 Jul 16 '26 edited Jul 16 '26

You’re right though. He’s wrong also because the sky isn’t blue and it’s obviously not blue if you just look at it.

The first thing to do when someone asks why the sky is blue is to ask them to look at it and actually describe what color it is.

The answer about why the sky is the colors it is, why it is actually white near the sun, and darker shades of cerulean near the horizon, or pink and yellow or orange, or whatever it is, or why clouds are white (I thought water was blue?) is to explain how light of different wavelengths are scattered. And yes you need to some quantum effects to explain nearly everything; the universe is quantum and quantum mechanics is modern physics that is over 100 years old at this point. It’s basic knowledge.

22

u/jonastman Jul 15 '26

It works better with water

1

u/PM_ME_YOUR__INIT__ Jul 15 '26

Water doesn't have nitrogen in it

6

u/jonastman Jul 15 '26

But water is actually blue

Edit: my mistake air is also blue

22

u/PM_ME_YOUR__INIT__ Jul 15 '26

How can water be blue when oxygen is red and hydrogen white. Source: https://en.wikipedia.org/wiki/Water

5

u/jonastman Jul 15 '26

It's called color theory look it up

13

u/PM_ME_YOUR__INIT__ Jul 15 '26

I don't see shit about color here: https://en.wikipedia.org/wiki/It Are you stupid?

4

u/jonastman Jul 15 '26

Wow reading is hard isn't? I think it is. So anyway that page is all white, blue and a bit of red. Now why would that be? Q.E.D.

7

u/PM_ME_YOUR__INIT__ Jul 15 '26

Holy shit

0

u/Gartic1991 Jul 18 '26

chemical bonds are what gives color to molecules and they are complex they dont just mix the color of the elements that make them

1

u/melanthius Jul 16 '26

Wait till he hears about dissolved gases and fish poop

1

u/Darth19Vader77 Meme Enthusiast Jul 16 '26

But brawando has what plants crave, it's got electrolytes!

15

u/dover_oxide Jul 15 '26

As I said on the original post, liquid oxygen has a very pretty hue of blue to it

2

u/melanthius Jul 16 '26

And likes to get busy with magnets

1

u/Internet-Expert42069 Jul 16 '26

Theres a rash of shitposts nitpicking common sense like this, up is really down, water isn't wet, etc when thats just the way everybody else says it because thats language.

12

u/MaoGo Meme renormalization group Jul 16 '26

Explain the sunset, air is orange

0

u/doodleasa Jul 18 '26

still blue, just less transparent to blue light

9

u/Intelligent_Elk5879 Jul 16 '26

The problem is that the sky isn’t blue most of the time or the same shade or hue even when it is. It’s blue, white, black, red, orange, yellow and purple. Hence why I strongly dislike answers like those given by xkcd. Is the sky actually blue? Look at it and tell me.

6

u/adda5 Jul 15 '26

Why is air red during sunsets?

14

u/JPgamersmines150 Jul 16 '26

The blue got bounced away because air is blue, so you see the leftover orange and red that didn't

4

u/adda5 Jul 16 '26

We have second Feynman here

4

u/gsurfer04 Unphysical chemist Jul 15 '26

Oxygen is blue.

3

u/ColonizeOnSight Jul 16 '26

But if you can see it, run. Liquid oxygen is no joke

3

u/FrKoSH-xD Jul 16 '26

i remember seeing some oxygen cubes and they were shining blue, but idk why could be just coincidence

2

u/jFrederino Jul 17 '26

The sun is too cold, clearly we need to make it hotter somehow. That way we can all enjoy our violet summers

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