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[Dozebôm Lolumzalìs]

Oops, should've checked Wikipedia first. Thanks.

[alway]

See Richard Feynman's book QED for more details.

[sjm9876]

It can also (as far as I'm aware) be described by the absorption and remission of photons (or emission and subsequent absorption, cause uncertainty principle), with the angle of reflection determined by the constructive interference of the photons.

The wonderful thing about physics is that there are often many possible explanations for the same result, especially in classical physics.

[Max™]

See Richard Feynman's book QED for more details.

Yar, it's a great source, Feynman was the man: http://www.feynmanlectures.caltech.edu/

[Putnam]

You have forgotten a really important fact: photons have wave-particle duality. They're not 'uncharged' as such.

Huh? I don't see how those are related at all.

[Max™]

Yeah, that's a headscratcher, plus, virtual photons are a big part of the transmission of electromagnetic charge in various models, so you could reasonably say they are charge in some sense, but wave-particle duality doesn't really matter there.

[Arx]

In classical electrodynamics, light is considered as an electromagnetic wave, which is described by Maxwell's equations. Light waves incident on a material induce small oscillations of polarisation in the individual atoms (or oscillation of electrons, in metals), causing each particle to radiate a small secondary wave in all directions, like a dipole antenna. All these waves add up to give specular reflection and refraction, according to the Huygens–Fresnel principle.

In this context, it's easier to consider light as a wave than as a particle, since it interacts electromagnetically with whatever it collides with. It doesn't make sense to consider a photon as having EM interactions, but it does make sense to consider an EM wave as having them.

If this doesn't make sense, sorry, I'm a bit sleepy.

[Max™]

Ohhhh, I was thinking you were saying that the wave-particle duality itself was the reason, I favor the wave description anyways.

[Arx]

Hah, no. I worded that first post poorly, sorry.

[Starver]

Ohhhh, I was thinking you were saying that the wave-particle duality itself was the reason, I favor the wave description anyways.

Spoiler (click to show/hide)

[Max™]

Because I loved that path integrals were a way to draw out a diagram of an interaction, apply an algorithm to it, and use that to calculate the scattering amplitudes and so forth of said interaction, so they show you a convenient way of seeing what happened, but were a major part of the development of quantum field theory where particles are just excited states of a given field. So in the process of learning about them you see how to draw them in a way that suggests they behave like particles, but gain the understanding that you then use the drawing to work out the actual interference rules from all the possible paths resulting from a more wave-like behavior.

Since we've tested QFT more we see cases where the particle explanation doesn't quite hold as well, so it's a useful way to think of things, and indeed waves aren't always the most ideal description of field excitations, but they're close enough for nuclear hand grenades.

[Calidovi]

Biology hasn't changed.

I agree for the most part. But 74s never made a point about the evolution of man, at least not in the quoted post.

Take a baby from the jungle and bring them up in the city. You get 100% perfect adaptation. That proves that tech hasn't had time to affect evolution. At the point that someone from the jungle is fundamentally impaired from ever operating at the level of city-folk, then you could make the claim that evolution was necessarily affected by tech.

A baby from the jungle brought up in the city immediately after before language development is from the city. If you're saying that anyone from the jungle can be integrated into society, just understand feral children's developmental problems.

Also, who gave a shit about how humans are evolving? We were talking about society. We're not Homo novus or whatever, but we have a far different society than we used to. Ancient Rome to right now is a far greater change than Homo neanderthalensis -> Homo erectus, regardless or the time difference.

But the baby-from-the-jungle's brain has actually been shaped by tech - 2 million years of hunter-gatherer tech. And that tech/evolution cycle explains all the cognitive adaptations to modern life (proved because hunter-gatherers do in fact adapt perfectly well).

Yeah, humans are adaptive. That's why we're adapting to the internet, and forming our culture with it.

Also, name one example of hunter-gatherer technology that we are automatically, instinctively inclined to and I'll tell you that it's because simple machines and trial and error makes sense. A feral child probably can't make an axe from the woods on their first try, no matter what the "Jungle Book" says.

I added it to my last post, but that's slipped to the previous page. Training a dog to do new tricks doesn't change their innate dog-ness.

Dogs are dogs, and men are men. Comparing the basic, instinct-based life of an individual dog to all of human society and development is fallacious.

Training a human to operate machines likewise doesn't change their innate human-ness. Sure, some things are going to be malleable, but other things are immutable consequences of how we're constructed.

Wait, so you originally said that our minds are shaped by hunter-gatherer technology, and now you say that machines don't change us? Where is the line drawn?

Please clarify your post, I can imagine that I've misconstrued many of your points. Also let me know if any of this in unclear.

[Reelya]

Biology hasn't changed.

I agree for the most part. But 74s never made a point about the evolution of man, at least not in the quoted post.

Take a baby from the jungle and bring them up in the city. You get 100% perfect adaptation. That proves that tech hasn't had time to affect evolution. At the point that someone from the jungle is fundamentally impaired from ever operating at the level of city-folk, then you could make the claim that evolution was necessarily affected by tech.

A baby from the jungle brought up in the city immediately after before language development is from the city. If you're saying that anyone from the jungle can be integrated into society, just understand feral children's developmental problems.

We're talking about evolution here. Feral children is a red herring. i don't know where to start with what's wrong with that argument.

The question was: have humans evolved to be innately different because of living in cities. My answer was "no" because primitive hunter-gatherers blend right in. They're entirely the same in the "nature" side of things. Feral children is "nurture".

Basically, that fact that people evolved purely in a hunter-gatherer scenario for millions of years can adapt so fully to city life within a single generation proves that the genetic adaptation for hunter-gatherer life are already perfect for living in cities. We shape our cities for ourselves though, so that should be expected.

[Calidovi]

Biology hasn't changed.

I agree for the most part. But 74s never made a point about the evolution of man, at least not in the quoted post.

When did we get back to evolution? I thought this was a discussion of human society.

If reading 'feral children' throws you off, just read the rest of the post without it. ¯\_(ツ)_/¯

[Reelya]

Obviously you didn't actually attempt to read anything I wrote from my very first post onwards, because I was always talking about evolution specifically. Basically I was responding to the idea that everything's changed because we've adapted to the modern world, therefore we can throw out all the old evolutiony shit. Well, we haven't really changed at all.

But if you want to talk about sociology and not science (which was the bit I was talking about all along) then why in heck have you derailed the farking science thread with a discussion that was already part of a sociology thread?