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Crazy Conclusions in Early Childhood

raisingfutureadults.blogspot.com

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Re: Crazy Conclusions in Early Childhood

#81

Post by nate_meurer »

darkerside wrote: post #79
darkerside wrote: post #64

Earlier quoted context omitted.

Crystals are by definition ordered by a very regular pattern. I don't fully understand the mechanism, but I'm not surprised that it exists.

Glass is not a crystal. Not sure what I was thinking. No idea why its surface is reflective.

Any abrupt change in refractive index, either higher or lower, will result in reflections. This can be somewhat intuited by analogy to sound waves, which reflect off of abrupt material density transitions.

This is how anti-reflective coatings work-- by "smoothing" the transition using materials that have intermediate refractive indices. E.g., flourite coatings on glass lenses.

Re: Crazy Conclusions in Early Childhood

#82

Post by photojosh »

spoonjim wrote: post #24
TedDoesntTalk wrote: post #4

That a 16-year old remembers such detail about age 3 seems… unusual. I don’t mean a memory here or there; this child remembers very specific experiences and the feelings he had about them when he was almost pre-verbal. Seems almost incredible.

A 3 year old can remember something at 16 if they regularly recall it. It gets refreshed like DRAM. I do this with my kids for special memories. They can remember everything they did at LEGOLAND the day after. So I have them tell me about it, regularly, and they remember it permanently.

I'd add, the "on this day" photo library feature is amazing as your kids get older and memories fade. Little video snippets (and live photos: priceless) from when your kids were 2, 5, 10 years younger. Searching for keywords from image/face recognition when you remember something and getting a real memory back.

Of course, there's a balance with living in the moment too, but as someone who forgets what happened yesterday, I try to document as much as I can.

Re: Crazy Conclusions in Early Childhood

#83

Post by barrkel »

nate_meurer wrote: post #81
darkerside wrote: post #79

Earlier quoted context omitted.

Glass is not a crystal. Not sure what I was thinking. No idea why its surface is reflective.

Any abrupt change in refractive index, either higher or lower, will result in reflections. This can be somewhat intuited by analogy to sound waves, which reflect off of abrupt material density transitions. This is how anti-reflective coatings work-- by "smoothing" the transition using materials that have intermediate refractive indices. E.g., flourite coatings on glass lenses.

I don't think people necessarily have an intuition about sound waves reflecting on material density transitions (the obvious one is air vs water but I guess unless you grew up near a lake or slow river you wouldn't know much about it), and I don't think it's clear how such an intuition - if present - would transfer from sound, which has a transmission medium, to light, which doesn't.

Sound is transmitted by waves of compression and decompression in the medium. In the reflection scenario that's is ultimately molecules of air and water hitting the boundary and transmitting some kinetic energy into the other medium and bouncing back, to some degree. You can visualize it as marbles hitting each other.

It's much harder to do the same for light.

Re: Crazy Conclusions in Early Childhood

#84

Post by darkerside »

barrkel wrote: post #83
nate_meurer wrote: post #81

Earlier quoted context omitted.

Any abrupt change in refractive index, either higher or lower, will result in reflections. This can be somewhat intuited by analogy to sound waves, which reflect off of abrupt material density transitions. This is how anti-reflective coatings work-- by "smoothing" the transition using materials that have intermediate refractive indices. E.g., flourite coatings on glass lenses.

I don't think people necessarily have an intuition about sound waves reflecting on material density transitions (the obvious one is air vs water but I guess unless you grew up near a lake or slow river you wouldn't know much about it), and I don't think it's clear how such an intuition - if present - would transfer from sound, which has a transmission medium, to light, which doesn't. Sound is transmitted by waves of…

I think that does make sense. A more extreme example is echos caused by sound bouncing off of solid materials. Definitely intuitive to me, unless someone can again explain why I am wrong. :)

That said, it explains why glass is shiny, but not necessarily why it is reflective. At least to my understanding.

Re: Crazy Conclusions in Early Childhood

#85

Post by nate_meurer »

barrkel wrote: post #83
nate_meurer wrote: post #81

Earlier quoted context omitted.

Any abrupt change in refractive index, either higher or lower, will result in reflections. This can be somewhat intuited by analogy to sound waves, which reflect off of abrupt material density transitions. This is how anti-reflective coatings work-- by "smoothing" the transition using materials that have intermediate refractive indices. E.g., flourite coatings on glass lenses.

I don't think people necessarily have an intuition about sound waves reflecting on material density transitions (the obvious one is air vs water but I guess unless you grew up near a lake or slow river you wouldn't know much about it), and I don't think it's clear how such an intuition - if present - would transfer from sound, which has a transmission medium, to light, which doesn't. Sound is transmitted by waves of…

If I think about the wave nature of light, then a material's refractive index is sort of the "density" of the medium. Light travels more slowly through materials with higher refractive index. As you know, this is actually due to the absorption and retransmission of photons from atom to atom, somewhat analogous to your marbles illustration of sound. Both models support wave-like behavior in aggregate.

Thus, when light moves from a "faster" medium to a "slower" one, refractions and reflections result that are similar in character to acoustic reflections.

That's how I think of it anyway.

Re: Crazy Conclusions in Early Childhood

#86

Post by mongol »

posterboy wrote: post #80
mongol wrote: post #26

Earlier quoted context omitted.

I remember how a ladybug tasted because I crushed one with my finger and put it in my mouth. Don't know the exact age but I were as old as children are when they do those things.

I guess your memory would describe it approximately as "not great", unless it had either been cause for panic, or an unreasonable desire for more of that polkadotted hotbod.

My memory is that it tasted awfully bitter.

Re: Crazy Conclusions in Early Childhood

#87

Post by gee10 »

chriskanan wrote: post #44
spoonjim wrote: post #24

Earlier quoted context omitted.

A 3 year old can remember something at 16 if they regularly recall it. It gets refreshed like DRAM. I do this with my kids for special memories. They can remember everything they did at LEGOLAND the day after. So I have them tell me about it, regularly, and they remember it permanently.

Spaced repetition is a technique for exploiting psychology's spacing effect for getting information to be stored longer [1]. That is (roughly) a memory needs to be recalled to be retained and the optimal time to do that recall is just before forgetting the material. This is implemented by Anki, which I loved using throughout my PhD and a few years afterwards with 20K+ flash cards on AI, math, and neuroscience. I star…

I run SpacedRepetition.com - glad to chat if folks want to discuss further! (Gabe@spacedrepetition.com)

Re: Crazy Conclusions in Early Childhood

#88

Post by soulofmischief »

borski wrote: post #77
soulofmischief wrote: post #62

Earlier quoted context omitted.

To be fair, many people think it's not OK for Google to be listening, and you should be careful not to accustom your daughter to tech surveillance.

Sure, but if she has generalized anxiety, adding more to the plate in the form of “oh, also Google wants to throw you in prison eventually” is just not worth it right now :) I’m exaggerating for effect, because kids do

I'm not withholding these details from my children.
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