Thanks man. And thanks for your service in the army!

Snow is quite different from ice when it comes to the way water molecules are organised. Each snow flake being a weird hexagon reflects much more light per molecule than ice which is much more organized. The more the molecules are organized, the clearer they're seen through.

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“What are you preparing? You're always preparing. Just go!”

Quantum fluctuations might make it a tiny bit less than 100%, to be pedantic

Ooof dude that's way above my wheel house. I got basics down but no where near that level of knowledge. I liked your original post cause I tell new Medics the same thing! I did work in a OR for a while and from experience ANA positive is super indicative of autoimmune but any more then that I'm clueless. I'm sorry about all that brother, it insane we know so much and so little that "medical mysteries" still exists. All the best wishes, when you get better here soon, come reply and lmk!

Basically all the calories you take in are burned as heat (you get a small amount of work, but the vast majority are heat lost). If you're eating 2000 calories/day and not adding to your fat reserves, you're almost certainly releasing at least 1960 calories/day as heat.

I believe I read once that the Mall of America in Minneapolis where it gets to -40 degrees sometimes doesn't have a heating source, and as an HVAC designer I believe it.

I feel like that's probably not true for most people. I imagine Pepsi is easier on the liver and brain, and diet Pepsi would be easier on the sugar. Not arguing that it's healthy, it's clearly not. But i think 10 beers is pretty definitely worse.

Oh, I love those. I had some recent record drawing projects where I only had scanned ancient BS like you said and a set of survey markups from a guy who couldn't write to save his life. Couldn't tell the difference between 3, 5, or 8. They all looked the same!

In the spirt of ELI5, Digital computing, at its most fundamental, is about breaking complex tasks into a bunch of yes/no questions. For example, representing the concept of '4' digitally is akin to saying yes 4x [to the question 'one more?'] then saying no . . . This is found at the basic level where ASCII codes come from having a unique 'number' for every conceivable character, to unique values for every color in the palette, to every command you can imagine.

While we might in our brains have a larger concept of, say, 10,000, or pi or 'scroll left,' it's all a rapidly iterated and refreshed set of yes/no questions for the computer.

The computer keeps track of the values for these questions with a whole bunch of spots where there is no voltage for a no and a certain voltage for a yes. They're like on/off switches for your bedroom lights, only they are turned on and off with electrical signals instead of fingers.

You can imagine with tasks of any complexity or sophistication, the number of switches quickly become huge and cumbersome. As others have mentioned, they used to be relays or tubes that were nearly as large as actual light switches.

Then they discovered transistors that were made of semiconductors. And the properties of these semiconductors made it possible to simply use an electrical current. A tiny piece of the semiconductor can hold that charge value [ie, none or some, yes or no] until another current comes along and changes it.

Now all those switches can be replaced with tiny tiny little blobs of that semiconductor material specially arranged to serve as tiny tiny switches, and they can be packed really close together. Again, as others have said, billions and billions in the same space that used to be one switch or vacuum tube.

Here, the conceptual limits are being refined by our ability to fabricate. These switches, tiny as they are, still need to be structured in an orderly manner, so we've refined our ability to make smaller and smaller versions of the 'blob' that does the work of a transistor keeping track of the on/off yes/no values. You can't just 'make the tiniest transistors' and stick them on a motherboard, you have to make them with the right connections and arrange them so they keep useful track of those billions of values in a meaningful way to accomplish a goal.

So the work since the advent of the transistor has not so much been computing in a different way as it has been making the fabrication process smaller, more precise, and more efficient.

>Nothing is 100% transparent

I'd argue that vacuum is kapp

Because snow is just a bunch of tiny crystals that scatter all wavelengths in all directions. When you think ice, you're thinking of a solid chunk of frozen water which refracts light the same way, albeit with a lower index of refraction. If the ice happens to be cloudy because of air or impurities, it will scatter more light and appear cloudy, all the way to the point of basically becoming snow white the more impure it is.

Edit: to explain scattering in an ELI5 friendly way, ever played with marbles as a kid? Most of them used to be transparent like glass, but we used to grab a subset and rub them against a rough surface like a pavement to make them opaque. In doing so, they would take a certain color. That's basically how light scattering works, the rough uneven surface doing the work.

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Anything finely divided has millions of facets that reflect light in millions of directions again and again. Nothing is 100% transparent. So the incoming light gets completely mashed up giving white.

Salt, powdered sugar, mist, a waterfall, ground glass, etc, etc, all the same reason.

So what you are saying is that we should welcome the lizard people as our new overlords?

Meant Union Station in DC, should have probably just mentioned Grand Central since it's the train station everyone knows.

I agree, but even in our own history there was life before trees and I guess that's more of what I'm concerned. Other things are flammable but without substantial things like coal and wood they simply wouldn't really be able to make fires hot enough to be able to forge anything stronger than like...bronze? I guess that's also needing to consider atmospheric content and stuff. Sorry if it feels like I'm arguing with you, I'm absolutely not trying to, I just don't have people that like this sort of thing that are willing to or are knowledgeable enough to talk about it

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Years ago, Pantone sold a physical set of cards, much like the cards for paint colors you see at Home Depot. Same idea: If you called out a specific Pantone color (by its number), you were sure of an exact color match. We built retrofit displays for aircraft cockpits. Often our display would sit side-by-side with the competitor's display we were replacing, so the colors of any symbol on our display had to be a darn good match with theirs, or the customer wouldn't accept it. We'd get a competitor's display, keep trying cards till it looked like a good match, then specify colors (by its number) to our software engineers.

That makes more sense to me. If fossil fuels or some sort of low level fuel source is almost a requirement when it comes to successful ecosystems as we know it, that makes me feel better about it. I have been thinking a lot about some poor intelligent species stuck in a pre caveman era forever because they simply don't have the necessary resources to advance.

Wood is not the only flammable material. And if we assume a carbon-based life form, it would be difficult to imagine them developing in an environment void of plant life.

Is this satire? You can't catch a cold through a cut. Only certain cells are susceptible to common cold virus/flu/coronavirus infection. The nasal mucosa, for example, is viable tissue for a viral infection. And it must be infected by respiratory droplets (infected saliva, phlegm, mucus).

AFAIK, there is no guarantee that fossil fuels will form in a life-bearing planet's geological history. But it's really unlikely not to. On Earth, the initial explosion of photosynthetic life took large amounts of CO2 out of the atmosphere. With nothing initially eating it, layer upon layer of dead biomass was laid down, and buried over geological time. When some alien microbe first figures out how to photosynthesize, it would inherently outcompete every other life-form on the planet, expanding far too fast for anything else to eat it. Even if the input of energy to the planetary ecosystem is something other than light - geothermal heat, perhaps, or some kind of chemical energy, or even radioactive decay - that energy will be stored in biomass, and unless it gets burned, that biomass will become fossil fuels.

The second possibility just doesn't make sense. It may not be something we recognize as plants, but an ecosystem has to have autotrophs of some kind. Something that uses an ambient energy gradient to turn the inorganic materials into more living stuff. And that stuff is inherently a store of energy.

Now, if your question is simply, "what would the chemistry be, if not like ours?" that's a different question, and one that xenobiologists are trying to figure out right now.

They're practical for us because we have had wood products since the dawn of humanity, but how does a budding intelligent species use any of those without wood or petroleum? Unless I'm wrong, early humanity would not have been capable of using any of those without wood burning first. Maaaybe hydro?