Posts Tagged ‘knowledge’

Liu’s Lizard

13 April 2011


Dear J-

Schrödinger proposed this experiment, which is now eponymously called Schrödinger’s Cat: you seal a cat up in a room in such a way that you can get no information out of the room — infrared, radio waves, sound, nothing escapes that would let you know if the cat’s alive and moving around, but otherwise fill the room with everything the cat would need to live — food, water, litter. You also seal up a bottle of poison with the cat in such a way that if you ooen the door the bottle breaks and the cat dies. How do you know if the cat is alive at any given moment? If you want to check you break the bottle and (disregarding the science of postmortem cooling) you wouldn’t know if that killed the cat or something else did long before opening the room.

Troubling ethics aside (of course it’s just a thought experiment, and no cats were actually harmed in this writing) it poses a philosophical question: what limits are there to our knowledge (and what are we willing to give up to find out?)? This morning after parking the van I spotted a lizard who appeared to be paralyzed with cold. Lacking time and incentive (as well as a stick) I didn’t poke it to see if it was still alive but later when driving off in the heat of the afternoon the lizard was gone. Did it wake up? Was it already dead, and did someone discard it? I’m never going to know; how soon does it take to get comfortable with that limit?


PS It does look unnaturally twisted, doesn’t it?


Knowing Smile

25 April 2010

Dear J-

We actually didn’t finish Chitty Chitty Bang Bang until today, but we’ve been humming songs from it since. And it turns out that the belt I’d bought yesterday was too long, so it’s almost like I got to do yesterday over again (note to belt vendors: what happened to plain strips of leather, nicely finished on the edges, roughly an inch to an inch and a half wide?). The excitement of Friday is lost in the foreshadowing of the work week writ large on Sunday afternoon.

I wonder about the paucity of digital distribution solutions; I understand that it’s important to keep track of copyright and provide proper credit, but doesn’t it seem that the minor amount of potential theft would be outweighed by the benefits of not having to provide physical storage and supply. For some industries — music — digital distribution is an accepted norm; for others — movies — folks are still buying and renting DVDs instead of sending bits around (there’s a seedy air about torrents, no pun intended); and for still others — books — digital adherents are looked upon as heretical, despite being perfect candidates (relatively small amounts of data). After all, all those physical artifacts end up cluttering the house when you’re done with them (we’re not going to talk about the box of DVDs that were watched only once).

There is, after all, a lot of important information out there to be digested; life works and whole careers continue to come on market and impact other lives. Was it Newton or Galileo who said that they saw further because they had stood on the shoulders of giants? The easier it is to know, the more we will know.


Shallow Field

16 August 2008

Dear J-

Saturdays seem to turn into photo days, for whatever reason, so let’s talk about f-stops, you and I.  F-stops follow the progression they do because they express the ratio of diameters; at f/1.0, the effective diameter of the lens matches the focal length.  Thus a 50mm f/1.0 (and they exist, at you-gotta-be-kidding-me prices) has a 50mm effective diameter.  At f/1.4, your diameter is 1/1.4-th of the focal length.  It makes more sense when you consider it this way:  since the area of the opening determines the gross amount of light transmitted through the lens (ideal lenses, here, and with modern multi-coatings, transmission ratios are pretty high); thus since area varies with the square of the diameter, it’s actually the square of the f-stop you’re interested in.

Hence, a f/1.0 lens transmits twice as much light as a f/1.4 lens, and thus you can derive the f-stop full stop scale (f/1.0, f/1.4, f/2.0, f/2.8, f/4, f/5.6, f/8, f/11, f/16, f/22, f/32, f/64, f/128, etc.) by taking the square root of the 2^n sequence (1, 2, 4, 8, 16, 32, etc.).  Consider it for a moment and it starts to make sense.  If you close down the aperture one full stop (f/1.4 to f/2.0, say), you have to double the shutter speed (1/30th at f/1.4 to 1/15th at f/2.0) to make an equivalent exposure — you show the film (or sensor) half the light, for twice as long.  All else being equal, why wouldn’t you keep the aperture as wide as possible?  Well, for one thing, lenses aren’t necessarily designed to be run wide-open, and often hit their optimum performance one or two stops down.  For another, aperture controls depth of field; low f-stops (big apertures) give shallow depth of field, which is useful for the Martha Stewart style of product photography, or if you’re trying to draw attention to one thing over another.

Isn’t it ironic, then, that in real life, opening yourself up to new experiences actually widens your depth of knowledge?  I’ve been reading about some guy out there who has some kind of beef with Democrats; he coauthored a book for the Swift Boat Veterans, blamed by some for torpedoing Kerry’s campaign in 2004 (someone please explain to me again how two draft dodgers came out looking more virtuous than a veteran, especially representing a party that prides itself on supporting the military), and he’s at it again with Obama fear-mongering.  Sadly, it’s not about the accuracy of the message, simple as it is in photography — if you’re using shallow depth of field techniques, make sure you focus on the right thing — but how repeatable the lie.

I remember from debate there were two sources you wanted to use for definitions, each useful to the affirmative (making a case for change) or negative (keeping the status quo) side.  And, depending on the side you had to argue, the standard reasons went like this:  affirmatives wanted to use a “common” dictionary like Merriam-Webster because it was the most reasonable to the greatest amount of people; negatives chose Black’s Law Dictionary because it was the most precisely focussed definition.  Neither was the best answer all the time, and you needed to carry around both, because you didn’t know what side you’d be asked to argue.  So it goes in life, so too in photography; develop your skills and make sure you use the right tools when needed.


Little Professor

19 November 2006

Dear J-

Sometimes I wonder about how much I really could have known way back yesteryear, when I spouted off regularly on such various topics as WWI-era Dreadnoughts, Star Trek (embarassing myself last night, having recited some details of Amok Time to a half-asleep theVet — I got the priestess’s name right, but not the betrothed), and hockey (hey, Spokane is close enough to Canada to count, and the Chiefs did win the Memorial Cup around the time I graduated). TheVet often tells me that I slip into an unconscious lecture mode; I think it’s a habit that I picked up from my dad and also from debate (thankfully, the only other lasting debate aftereffect has been a predilection for Phoenix Wright games). It makes me wonder (with a fair amount of dread) what kind of horrible influence I’m going to pump down to the next generation, and if they’re doomed to the same corduroy-wearing factoid-spewing fate.

No secret, theVet is pregnant. We are with child, in gentler terms. But that was the easy part — six months from now, how do I suppress the urge to cram the sum total of human knowledge into an unsuspecting infant, how I do know I’m doing right by the child, how do I blend the same measure of steely discipline and self-esteem needed for this world? Here’s a shiny new life, now just make sure you don’t mess it up for them. Agh, the responsibility.

I know I’ll be able to associate answers with questions, but that doesn’t necessarily mean that I have the answers. We’ll muddle through together, unborn fetus, theVet, and I; we’ll learn together and as much as I know I’m going to be able to teach you, I already can’t wait to learn more from you. So hurry up already and stop making your mom nauseous and tired (and some sort of amazing ravenous eating machine) so we can meetcha. I want you to know as much happiness in your life as I’ve known in mine; I want to watch you laugh, watching me with bright curious eyes; I want to lead you to the same castles and pyramids and knights and emperors to see the new blooming bright every day. I already know you’ll be wonderful.

J-, I want you to meet baby nemo, and don’t tell me you’re too busy or don’t know the way. Anyone who can sit through Scent of Green Papaya (will he pee into the pot or not?) can spare a few moments to meet someone completely new.