Wednesday, February 29, 2012

Observations of Nature in Art

May 23rd 2012, Please read this DISCLAIMER before proceeding. Today's edits are in red.

RAINBOWS:

A. What is wrong with this picture?

(Thanks to Shailesh S for motivating the following.) 
Have you ever seen an elliptical rainbow? No? Let's ask ourselves why not? Imagine looking at a circle, a child's hula, or a hoop-earring in a 3/4 profile photo of a beautiful woman looking out over a seascape (just saying!). The hula-hoop appears as a circle only from one particular angle, out of 2 Pi steradians. To anyone else looking at it, it appears as an ellipse. This becomes clear when they are as far to one side of you as you are from the hula-hoop. Now imagine that there is a big evening rainfront about 20 miles to your East, and you see a rainbow (in the East, why?), and your friend who lives 20 miles to your North texts you, "i c byu t ful rnbo, do u?". You respond, "Yes, i c it 2, as circle, so u must c it as ellipse." She txts bak, "No way, mine is circle 2! ;-?"

Now, the only way the same real object can appear as a circle to all viewers is if it is a ... sphere! Let's accept that a rainbow is not a sphere (in four dimensional space, it would be! Isn't just that a reason one would wish String Theory to be true?). Then we have to conclude that a rainbow is not real! What one means by "not real" is that you can't project it on a screen. Such images are called "virtual images", like the image you see through a magnifying glass. 

We see the rainbow, because the lens of our eye collects the light reflected and refracted from all the raindrops and projects a real image onto our retina. If we consider "seeing an object" to mean sensory perception of light emanating or reflected or otherwise having interacted with that object, then what we are seeing when we "see a rainbow" is all the raindrops!

So the only real image of the rainbow is the one that is projected onto your retina and which is then processed by your brain. Now since that is just as true for your friend as it is for you, what that means is that each and every person has their own personal rainbow, and she or he is at the center of it!   That is a pretty good analogy for consciousness of the universe.

You'll never see a rainbow as an ellipse, less so as co-axial elliptical bands. If we insist on imagining what it would look like to another observer far to the left of us, it would still not look like the above where the red arc remains on the left edge and the blue arc remains on the right edge. The colors form concentric annular discs, so the red arc should be imagined to stay on the outside edge of the elliptical form, and the blue arc on the inside edge.

B. What is wrong with this picture?
 The three rainbows have three different centers, implying three sources of light! On a planet with three or more spectrally identical suns, this landscape is possible. However, since rainbows are virtual images, they would not obscure one another.

Ignoring the rainbow on the right, non-concentric double rainbows are in principle possible. The lower one (whose center is the shadow of your head and is below the horizon) is the normal one formed by light from the sun refracting and reflecting off the raindrops. The upper rainbow, with its center above the horizon, is formed by sunlight which is first reflected by the body of water in the foreground, and then impinges at an upward angle on the raindrops! The center of the reflection rainbow is where the shadow of your head would appear to be after reflection from (a continuation of) the expanse of water. Because of the landforms, the upper rainbow should be incomplete except where there is water directly below the lower rainbow. What a thought-provoking painting!

Now, just as we can see multiple shadows due to multiple lights, for example at night in an illuminated parking lot, with some luck and lots of practice with a hose spraying water, one might be able to see three rainbows as well. 

C. What is wrong with this picture?

The sun is under the rainbow? Whatever the artist is smoking, I want some! This was seen by some of my readers as being derisive towards the artist. By no means! I really really do want some! A rather prosaic way of achieving the same effect would be to have a filtered mirror in front and just to the side of you while looking at the rainbow. By the way, even if the sun was above the rainbow it would still be wrong. Here is an excerpt from the page of an observant artist : "On a showery day, one may be blessed with the appearance of a rainbow. It is visible in an area of the sky opposite the light source."

D. What is wrong with this picture?
The order of the colors is inverted, as the artist could have ascertained by umm ...  looking. But hey! Why look at nature when you can do an art project? Or go online to check whether it is raining? What I think bothers me here is that young children, even when they see a rainbow, are perhaps missing the time with an adult who could help them look at the rainbow. By which I mean observe and mindfulness, which is a first step towards both science and art.

The angles for the first maximum, or the primary rainbow, are proportional to the wavelength. A rainbow, or anything else with a spectrum, requires dispersion, i.e. wavelength dependence of the relative refractive index of the material of the drops (water) in the atmosphere (air). In water, shorter wavelengths (blue) are dispersed more than longer wavelengths (red). Hence one might expect that red be on the inside and blue be on the outside, as in the above painting.  However, the light is also reflected from the back wall of the droplet and purely due to the geometry of this reflection, the colors cross each other and are inverted. See the wikipedia rainbow article.

E. What is wrong with this picture?

This is more subtle! Again, all the artist need have done is look! From inside to outside, the colors in the secondary rainbow go from red to blue! The secondary rainbow is formed when the light is reflected inside the rainbow twice! This causes the order of the colors to be inverted yet again and back to the original "blue is dispersed more". I'll confess that I haven't figured out the geometry of this, and neither has wikipedia.

F. What is i) right and ii) wrong with this picture?

i) The two rainbows are concentric, and the shadows cast by objects are consistent with the position of the sun. That is, the line joining the observer to the center of the rainbow is parallel to the lines joining objects to their shadows.
ii) However, I would have expected to see the shadow of the artist's head at the geometric center of the rainbow, near the bottom, but by my reckoning within the frame of the painting. This is a minor quibble.

G. In contrast, what is right with this picture?

The order of the colors of the secondary rainbow. An artist actually looked at nature! (Okay, the last sentence is unneccesary.)

G. What are two things wrong with this picture?

First, the only way the rainbow can be seen in front of the background trees is if there is rain or mist between the artist and the trees, which, from the clarity of appearance of the sheep and houses near the "pot-of-gold" point, does not appear to be the case. Second, from the artist's viewpoint one can see close to 180 degrees worth of the rainbow, implying that the sun is at the horizon. This is inconsistent with the rather short length of the children's shadows, which indicate the sun to be about halfway to the zenith, or about 45 degrees above the horizon, in which case the rainbow shouldn't be visible at all! (The sun has to be less than 42 degrees above the horizon, since that is the outer conical angle of the rainbow.)

 SNOWFLAKES: The next time I see non-C6 symmetry snowflakes I'll scream.

Scream 1

Scream 2

Scream 3

The USPS, which tends not to be particularly science friendly, did use actual photos of snowflakes for their stamps.

To which one can only say,
"Naught immortal hand nor eye
  could frame thy C6 symmetry"

Next up: descriptions of nature in Turgenev.

Tuesday, February 28, 2012

WhatDoesThis MakeWarudkar?

If you have anything political to say that is more than 5 lines in length or likely to invite/incite responses, I think it is a good idea to write it on some blog of yours, and to the discussion group, mail only a link to your blog.

Discmailer: If you are not a member of the Hostel 8 B wing 1985 (IIT-B) yahoo group, this is probably irrelevant to you.

GAWAS 10 (However, since having to pay $4.89/gal. of gas is enough to make AW go completely ballistic, I just have to admit that my calibration is off. Perhaps we can work on a new scale: GetAshishWarudkarBallisticScale.)

Warudkar,

This post is NOT to criticize your politics. Since I do not like you, I can't give you any gaalis. However, based on the following, people can make up their minds as to what you are. (The images are screen captures from the YahooGroup. Click on the image for better resolution.)





Those of you who have looked at the post know that, at least at the beginning, I was careful to keep politics out of it, all the post has are photos of food and people eating it. AW's response is longer than my original post.

A little later:


Since AW doesn't want to see my "lefty" politics, he wants to regulate this space and keep me from posting links to my blog. Hower, like most anti-regulationists, what he really believes are that regulations only apply to others, not to those -like him- who are the "chosen ones". Witness the following, which is only about 1/8th of the full-length article that AW chose to cut-and-paste into his mail message. (I can hear you shouting, AW!)

Is AW now against Copyright protection as "too much regulation stifling innovation"? Next will AW launch a anti-regulatory tirade against the Patent office? Inquiring minds all are all agog!

Wednesday, February 22, 2012

Five-toe running non-shoes


After dissing these shoes for years, I saw them on sale and bought a pair. My reaction: love them!

I've been running barefoot on the sidewalks here for a year or so. Why? because I can! No shit, as in India, and no snow as in Buffalo. I've learned to run on light gravel and can take the occasional pebble in stride. However I've also been hill running for about a year on the trails in Rancho San Antonio and have wanted to try running lightfoot on the trails. I've tried with varying degrees of success to run in Tevas or Chacos. They work out OK, but as a rule are too heavy and hot.

I am trying to get in shape so I can run with _. As many of you know, his nickname for me in IIT was "Slow". In fact he refuses to run with me even on adjacent treadmills, claiming I run so slow he has to make his treadmill go backwards so I can keep up.

A few months ago I got a pair of open Keen sandals and have run in those on the trails. They are quite light, the problem has been that once gravel gets in it is impossible to shake out. Also, my big toe still ends up hitting against the front of the shoe.

When I first got the Vibram FiveFingers, I went for a walk in them to try them out. A number of times I had the uncomfortable feeling that I was walking around naked, which is opuzzling becaise I walk barefoot quite a lot and have never felt "naked". The next day I went for a run in the hills, reallhy felt comfortable and ran well. SInce then each time I've run in them I've hit some personal best, mostly in terms of how high I've been able to run without stopping to walk. For example, on the second day I was able to run all the way around a loop that previously I had had to stop on twice. On the third day I ran it in the opposite, steeper direction and on the third day I ran a different trail to a point that had previously taken me 3-4 rests.

What do I note is different?
1) Sensations! You feel the ground beneath your feet. If you are a sensualist, you'll love these. You also feel the wind between your toes.
2) Lateral stability, since you no longer have that ridiculous 1.25" of sole below your heel, with a sharp edge just waiting to lever you over and hence twist your ankle. Your foot lands, and it is contact with the ground.
3) Because your heel is lower, your calf tendons get much more of a stretch and a workout. My strike was much more full-foot ball toe, and the feet muscles get a workout as well.  So watch out for the lower leg workout at the beginning, similar to when you start sand running for the first time.
4) They are so much lighter, on the way back, even when I was more tired, I felt like I was flying.
5) When you finish a cross-country run, you notice all the grass stalks stuck between your toes.


Thursday, February 16, 2012

OccupySnaFu

Jan 24, 2012

My heart sank the moment I walked up to 101 Market and saw the 8 large aluminium trays of food already there! Every person I had asked had insisted on their great need for food at the General Assemblies, and nobody mentioned to me that they have a semi-regular donor who buys and delivers cooked food most GA nights. On their website, the page which is supposed to have such up-to-date info for potential donors hasn't been updated since October! (As of last night their WebMaster was asked to resign and, apparently out of spite, curtailed access by other Working Group members.) Since they have no kitchen, they have no Kitchen Working Group, and there is no single point person who integrates "distributed information" (more on this later). My kitchen contact Meagan is involved in many other more important Working Groups (e.g. Financial), as well as reciprocal commitments to other causes (e.g. yesterday Meagan was to attend the first anniversary of the Egypt street protests), in between making a living (last night she was called to the restaurant to substitute for another employee. Have I mentioned that she is a Stanford grad.? - employed waiting tables! Who in their right minds thinks this is by choice?). In addition, Meagan's priority, perhaps, is and should be to ensure that there is food. So if there is uncertainty about the regular donor, she can't afford to turn away another. Hence the double-booking.

My on the ground contact for that night Miles apologized for not having called me as soon as he found out there was food there already, but in his defense, let me point out that the Occupy site is fairly dynamic. While the General Assembly proceeds there are satellite discussions, new people coming in that need to be filled in, pamphleteered or whose questions need to be addressed. Plus, Miles may have seen the task as solely to help me unload and serve, and there is a general skittishness about making decisions without "consensus". Distributed decision-making doesn't work either.

My reaction? Of course, personally frustrated or offended, "never going to bring them food again", my home-cooked food going to waste etc etc. OK, over it.

The fix: I decided and told Miles I would just take the stews back with me and refrigerate them for another day. He then had the excellent thought of taking it to Oakland this weekend, where they plan to take over an abandoned building and establish Occupy there, with a social center, first aid post, full working kitchen etc. A big call is going out, Move-in day rally is at noon at Oscar Grant Plaza and a two day festival is planned. So my thought was to find someone/place in Oakland where I could drop the food off on Friday night for the OO social center. There was also a large amount of food left-over from the cooked food donation - three trays each of rice and soft flour tortillas, which I volunteered to take back, refrigerate and deliver to Oakland. Somehow! I've come back home with more food than I left with!

The Solution: RyanRh, independently of me and my problem, boldly announced the formation of the Post of Food Coordinator and Food Point Person. He is going to be my main contact henceforth, and will coordinate information for me. Plus, he has a place in Berkeley where I can store all the food on Friday night for the Oakland events. And I now have Aluminium trays for my food so I don't have to take my pots.

The best part? After the General Assembly, Big Mike and Miles still had not eaten, neither had I, and the pseudoSpanish rice and plain soft flour tortillas looked unappetizing compared to the stews I'd cooked.
Vegetarian beans and greens
Beans Greens and Hotdogs

 So 6 of us went back to where I'd parked on Beale and Market and ate my stews out of the back of my station wagon,
Mike and Miles

sitting on the curb. And I now realise that I seriously overestimate how many people 3.5 gallons of stew and 8 kg of cooked rice can feed, if the people are twenty-something guys who haven't eaten all day and are allowed unlimited seconds.

Distributed Information and Decision-Making: I know various people in OccupySF, one of whom, Meagan, has been my principal contact so far, the others have mostly been helpful with physical aspects like carrying things back and forth and serving food. From the other extreme at which information is present, at a minimum the Regular Food Donor knew that food would be available that night, but there is no central clearing house with meal requirements that both RFD and I can access. Both RFD and I must know Occupy Peeps in common, though it is not clear that Miles knows RFD. Why could I not have been in touch with RFD earlier? Because there is no central clearing house for responsibilities/roles and contact information. Because decision-making is diffuse, no one person was in the position of making the connection (RFD's peeps know my peeps, which is a 3rd degree connection.). From the computational analogy, you still need one single processor for integrating the assignment of tasks to the other parallel processors and interacting with the human. All processors are equal, some processors just have to be more equal than others.

OccupySF really needs a web-based information clearing house and space for community contributions. Maybe with a new webmaster.

Outcome so far? I've got contact info for other possible Food coordinators, met and interviewed various other new people: a latina-palestina, an artist doing political Occupy related work, and 2-3 people who are engaged in the sustainable food movement - community gardening, integrated agriculture and sustainable landscaping. Miles has his own landscaping company and now is interning with SF Parks and Rec. Dept. Someone with expertise in helping communities self-organize should connect with him and help out.

How did the GA go? I haven't yet reached consensus on that, most of me thinks it was a waste of time and inefficient and too much time is dedicated to the opinionated nay-sayer holdouts who exercise their effective veto power to prevent things from moving along, but my left pinky wants to be heard, the rest of me respectfully listens to its point, that this is the nature of the beast of consensus decision-making and hence it refuses to join in the general censure of the GA by the rest of me and refuses to walk-away. We tried to decide to vote and adjourn but Left Pinky still has something important to say, even though it has been pointed out to it that everybody else has heard this same point, has understood it and disagrees. So we continue. Once the motion passes unanimously I'll let you know my opinion about the GA proceedings.

Intransigence, Theological

What makes me an intransigent or uncompromising atheist?

A friend of mine in Buffalo, the son of a Methodist preacher, labelled me as the only “evangelical atheist” he'd come across. I was young then. As part of the conversation, he offered me an “out”: Wasn't I an agnostic, or skeptic? I responded that for me as a scientist it would be a cop-out to be just agnostic or skeptical in the face of the overwhelming lack of evidence in favor of … whatever it is that is not out there. It is true that being skeptical or agnostic about WIITINOT, fairies or the Great Halloween Pumpkin is not quite the same as being skeptical or agnostic about say the ether or caloric. The theories of the ether or caloric made clearcut predictions (which were then falsified by counter-evidence), unlike religion or String Theory. So the existence of WIITINOT has not been disproven, nor can it be. It is just that the evidence in favor is … underwhelming, and I invoke Occam's razor.

Now that only explains why I am an atheist as opposed to an agnostic or skeptic – it does not serve to functionally distinguish between an atheist and an agnostic. I asked myself what it is that makes me an atheist. An agnostic or skeptic is open to the possibility of admitting the existence of WIITINOT, and hence one can (and should) ask of an agnostic what it would take for her or him to admit the existence of WIITINOT.

I am only agnostic implies that there exists some hypothetical event which would leave me no choice but to admit the existence of WIITINOT.

In my case, however, there is absolutely no imaginable event or series of events that would force me to accept or even suggest to me the existence of WIITINOT. This is not to say that there are no phenomena that I can't explain, nor that if something mysterious were to take place in front of my eyes I would be able to explain it. I would be happy to admit my personal ignorance, but before attributing the event to some WIITINOT, I would be assured that some human either already can explain it naturalistically, or that in the future humanity would eventually be able to explain it naturalistically. After all, none of us understands derivatives (the financial instruments, not the calculus kind), but we don't usually invoke them as evidence in favor of the existence of WIITINOT.

400 years ago no human being understood the rainbow, and it was an ineluctable mystery attributed to WIITINOT. Now, the immense majority of even us educated humans still can not explain the rainbow (nor even describe it fully), but it is no longer a mystery that necessitates the existence of WIITINOT, we all know that there is some human being, likely a physcist, who can explain it fully.

I repeat, there is absolutely no imaginable event or series of events that would force me to accept or even suggest to me the existence of WIITINOT. By modus tonens, I am not only agnostic, I am a full-blown, unremediable closed-minded atheist.

That doesn't prevent me from being friends with NAIFs – NonAtheistIntelligentFaithers. (My friend dissuaded me from referring to nonAtheists as “credules”.) Witness my friendship with Cosmic, who is a christian. On the morning after the day I met him in Las Vegas, in his pickup truck on the way to climb, I noticed a handsewn dashboard cover, a wooden cross mirror ornament etc. I asked him and he explained, that he was a christian (Christian?), that Jesus had walked this earth, that he died on the cross for us and that his love for us … that Cosmic felt Jesus' love for him, as he felt Jesus' love for everybody and that he hoped I wouldn't mind his talking to me about Jesus, because he would. I told him I was an atheist and I didn't mind at all, I would love to hear what he had to say as long as I could ask questions and discuss things, but that there was nothing he could say that would convert me and that I was not looking to convince him either. Cosmic said very slowly that was fine, he just felt compelled to talk because he felt Jesus' love.

So later that day when I slipped on a hard move, 15' off the deck, and nearly fell, and managed to make the two or three moves up to the large hold, and looked down at Cosmic with relief and pride and then exclaimed upwards, Thank You Jesus!, Cosmic understood me, you'll be a Believer yet.

And when he called me this week to tell me that his prayers would be with me, I understood him, and was able to honestly tell him that my prayers would be with him during his shoulder surgery.

I have two take-aways: One, agnostics and skeptics should be challenged to state the conditions under which they would admit the existence of a WIITINOT. Two, if you are inflexible, decided, obdurate etc., you should declare yourself as such before entering a discussion.