A car for your Valentine

On my last morning in Chicago, as I started to pack, I looked out of the window and saw a pink vintage car standing outside the IBM building. I kept an eye on it through the morning as I got ready to leave. It was stood there through the morning’s rush. As I was about to leave my hotel room, I took a parting shot of Chicago, the one you see in the featured photo. I spent that day and the next in flight.

Later, after I’d arrived home, I showed the photo to The Family. Her diagnosis took into account the date, something I’d forgotten about. "It must be someone’s Valentine," she said.

Patterns from turbulence

Walking along a beach before sunrise I saw a piece of brain coral had washed up at night. I have no idea what are the uses of the intricate patterns on the coral. The valleys between the ridges are where the feeding tentacles of the coral rest when they are not waving around. But why is are the ridges so complicated in shape? I had no clue about this. But I thought I should be able to understand the pattern in the sand around the piece of coral.

Small scale turbulence in water runoff on a beach

As the tide recedes, waves break near the shore, and the water runs up the sand. Then, the water drains back. As you can see in the photo above, the water breaks into little eddies as it drains, and the eddies conjure up the pattern in the sand around the piece of coral. You can see a pattern of parallel grooves.

The spacing between them is determined by the viscosity of water. It turn out that if the water tries to drain away with a speed of about a meter per second, then turbulent eddies of size of about 5 millimeters should be seen. That size is about the smallest scale that you can see in the pattern. Interestingly, this gives us a way to see how fast the water drained away after the water has gone. Look at the smallest structure in the pattern left by the water, and the speed should be inversely proportional to this. This means that the finer the pattern, the faster the water drained!

This is all about very small scale patterns. There is much more to the formation of patterns in the sand, as another blog discusses. As I walked about, the horizon began dipping towards the sun, and I was distracted by the easier pattern of the daily sunrise.

The 10 best ways to find my blog?

Here’s a nod to The Wife of Bath who sprung this meme on me. What are the most unexpected search terms which led to this blog?

  • For enigma can anything beat the search term "don don don"?
  • "75/300 the courtesan" led to my blog? What happened to the other three quarters?
  • My favourites include the very serious question "how to fill a cheque of almora urban bank". I hope my step by step illustrated guide helped.
  • The most esoteric was "best guarded secret recipes of 19th century". Mum’s the word here. The only secrets I spill are the ones which you already found.
  • Did I really have photos of "men dressed as women in public" on my blog? And if I made a "kerala elephants height list 2016" why can’t I remember where I put it?
  • "poison plants in tamilnadu" would not be a criminal query, would it? And neither is "classic front porch pillars tomb" I hope.
  • For sheer desperation the query "is when go bhalukpong there have any pass give" is hard to beat. I hope I answered that gently.
  • And finally, a cri de coeur: "wine shop distance from highway miter in assm"

No entry

noentryWalking around Lisbon one has a distinct feeling that people do not like one-way streets and the crazy traffic routing. No entry signs are constantly vandalized all over the central part of the town. Every time we took a taxi we found that it would first go in a completely crazy direction. The friendliest of drivers would drop us at some street corner and say things like "Walk down that road and take the first left." Going to the doorstep presumably was just too round about.

On the other hand, if you do not have no entry signs, you may just ride a bike up to a point of no return.

Look on his works

Outpatient building of the J. J. Hospital in MumbaiIn my decades in Mumbai I’ve passed the J. J. Hospital often enough to look up the fact that it is named after the 19th century philanthropist, Sir Jamsetjee Jeejeebhoy, who donated the funds required for setting up this hospital. I’d never had to visit the hospital. So this week when I had to look for the outpatient department I realized how large it was. The doctors who I know claim that interning here is the best training possible, because of the volume and variety of cases that you need to attend. As I arrived at the neo-classical facade of the out-patients building, it was clear to me how large this volume is. The next morning I read in the papers that I had underestimated the numbers of cases the hospital deals with; apparently this week medical interns are on strike, and the number of visitors has dropped dramatically. As I thought about this, I was reminded of an observation by Atul Gawande about the innovations in medical practice created in Mumbai just to keep up with the demands on services.

Statue of Jamsetjee Jeejeebhoy in the hospital named after himI wandered into the administrative building for the case papers I was there for. The crowded corridors smelt of strong bleach. As I stood in the queue outside the clerk’s office one of the people ahead of me tried to take off his slippers before entering. The clerk was furious “This is not a temple”, he told the man, “You are not here to pray”. After my work was done, I walked through the busy crowds to an alcove which held a statue of the person the hospital is named after. One person came by, took off his slippers and placed a flower at the feet of the statue. There was a small pile of flowers there. I thought that it was good that the staff kept the distinction between a hospital and a temple in mind. But for the poor who come here for treatment, the availability of government health care is a prayer come true.

There is a little donations box near the base of the statue. Even if it were full every day, it would not suffice to keep the hospital running. I wish that a larger fraction of my taxes would go into maintaining and expanding such health services.

Bird sounds

crow

Kolkata is green. I was surrounded by trees. You could hear the sun rise through bird calls. As in all Indian cities, the most numerous were the crows. But the greenery just outside the window meant that you could not miss their activity. In this season it was nesting. It seemed that every crow was in search of long thin twigs with which they build their untidy nests. Crows don’t seem to have a sense of which twig they need, and often try to pull fairly thick twigs out of trees. Continue reading “Bird sounds”

Simple pleasures

ducks

Mumbai does not give you the simple pleasure of standing by a pool in a park and watching geese swim by. Delhi does. On this count I score Delhi ten on a scale of one to ten. Work brought me to Delhi, but in the evening before I dived into a series of meetings, I followed the locals into a lovely garden in the middle of town: the Lodhi garden. The sun was about to set when I walked through this crowded park and came to the pond full of geese. Some of them stood about in the shallows and honked; others glided through deeper waters, submerging occasionally and coming up looking satisfied for no visible reason.

purplemoorhen

In the middle of these large white birds I saw a small dark thing swimming rapidly by. Was it a duck? No. When I looked at it the purple colour was clear. A lone purple moorhen glided past the cacophany of geese. I stood by the pond as the sun went down, enjoying these utterly commonplace sights in the company of the hordes of Delhi.

What makes gravity wave?

Occasionally something comes along which is as exciting as travelling, and makes me want to write off-topic. Newspapers have been full of the story of the discovery of gravitational waves. One corner of Mumbai is full of boffins who know all about this. I tried to find out from experts why this is interesting. This post is a broad-brush picture of what I now understand.

When I throw an apple upwards, it does not continue to move in a straight line. Its velocity changes: the upward motion reverses and becomes a downward motion. Newton realized that this change in velocity (which he named acceleration) means that some force acts on the apple. This is the force of gravity.

The planets go around the sun. This means that each of them is constantly changing its direction of motion (think of going round a tree: at some time you may be moving east, halfway around you will be moving west; the direction of your motion has changed). This change in velocity must also be due to a force. Newton ascribed this change to the sun’s gravity. Then he computed how the gravitational force depends on the distance from the sun, and came to the famous conclusion that it changes as the inverse square of the distance.

Gravity is a force field: everywhere in space the sun exerts a force. This has different strengths at different places, but always pulls in towards the sun. We are used to thinking of this force field as a static thing: it does not change with time. If it did, then the orbits of the planets would change with time.

Three centuries after Newton, and a hundred years ago, Einstein wondered about what new experiments imply about gravity. At that time experiments had begun to demonstrate that nothing can travel faster than light. Einstein applied this principle to gravity.

If the sun moves from one place to another, the gravity field around it must change. Since the force of gravity always pulls in towards the body, at one time it must pull in towards one position, and at another time towards another position. How would a distant planet react to the change in the sun’s position? Since nothing could move faster than light, the force of the sun’s gravity at the planet could not possibly change instantly; the planet would continue to move as if the sun had not changed its position, until this information caught up with it.

If, for some reason the sun jiggled back and forth, then the force of gravity on a distant object would jiggle back and forth, with a delay because of the speed of light. But slowly propagating jiggles are exactly what we call wave. So we figured that there are gravity waves! Such waves are exactly what were detected a year back, and announced yesterday.

So why don’t we see this all the time? First, because the motion of the planets is much slower than the speed of light. So much slower that we are not even aware of this universal speed limit. The planets behave as if the field of gravity adjusts itself instantly. Of course, particle accelerators routinely accelerate electrons and protons to very near the speed of light. But gravity is such a weak force, that we have no way of detecting the gravitational fields of these accelerated particles. This is why it requires objects 30 times as massive as the sun, moving close to the speed of light, to make gravity waves which can just barely be detected by the LIGO experiment.

Gravity waves are interesting, but it is also fascinating to listen in on a global conversation across centuries between hundreds of scientists which we marked out with simple milestones: Newton in 1687, Einstein in 1915, LIGO in 2016. The work of Newton depended on painstaking observations, calculations, and refinements of the understanding of planetary motions stretching back to the beginning of human history. From there to Einstein was a round-about path which involved Chinese and Arab observations about magnetism and electricity, leading to Faraday, Maxwell, and Bose. The trail from there to LIGO is also as fascinatingly branched and intertwined and spread across our globe, as you can judge by the names and addresses of the 1000 authors on the paper.

Chor bazaar

chorbazar1

An off-beat walk that one can do in Mumbai is to stroll through Chor Bazaar. To get there, follow Mohammad Ali Road until it crosses S. V. P. Road (Sardar Vallabhbhai Patel Road, if you are a pedant), then go westward along S. V. P. Road and turn into Mutton Galli.chorbazar2 Why chor bazaar should displace the mutton vendors whose galli they sit on is a topic ripe for urban historians. But the moment you turn into the road you know from the bizarre collection in each shop that you can be nowhere else.

One of the first stalls that I saw had used fans of all descriptions: exhaust fans, pedestal fans, table fans, and ceiling fans were what I recognized. The two young men selling these things were not averse to being in a photo. Further down was a bright yellow shop which sold any variety of hardware. I spotted a camera tripod standing in lonely majesty among polishing wheels.

chorbazar4

If chor bazaar was really a den of thieves anytime, that must have been long ago. It is rapidly gentrifying. A couple of turns later we came across a section of the bazaar which looked like a supply store for films. There were period object: empty tins of Cadburys from the 1950s, an empty cigarette tin of the same vintage, even some tins of patent medicines which could easily have been used by Sadhana in one of her movies. chorbazar3 Further along there was a small store selling vintage advertisements. When you looked closer they seemed like today’s idea of the 1960s. Could they have been real? It would need research to establish it either way.

We walked on and came to the section of the market which sold furniture and light fixtures. The furniture vendors were quite clear about which of the pieces were reproductions and which were new. Perhaps this depends on whether you know wood. Ten years ago I’d seen a genuine Art Nouveau piece, a tiny shelf with an asking price which was a touch more than I was ready to pay. I still regret not bargaining for it.

Today I saw an imitation Art Deco piece made of the right wood and materials, but looking too new. The price fitted my evaluation.chorbazar5 In a nearby shop I had a long chat about an Art Deco bar which seemed to have been made to the specification of an eccentric Parsi gentleman. Apparently much of the older furniture which reaches the market today is sourced from the estates of Parsi families.

It was getting very warm by now. The two days of winter in Mumbai are over. I looked across the lane from the furniture shops and saw a tiny stall which seems to specialize in lamp shades. The shopkeeper was taking a siesta. It was good to take the hint and bring the walk to an end.

Flower shower

Just west of the Eastern Express Highway at King’s circle you will run into an Ayappa temple, a Nalli sari store, and a variety of small Tamil eateries, all signifying that this was once an enclave of Tamil brahmin culture in Mumbai. Although you hear as much Gujarati and Marathi on the road today as Tamil, it still remains Tamil in spirit. At the eoad crossing leading in to the Ayappa temple is a flower market.

flowerworkera

In the afternoon the flower market is quiet, but you get a strong feeling that the pace quickens at other times. The morning must have seen a rush of devotees to the temple, and the evening’s customers have yet to arrive. Everywhere people are stringing togther garlands of flowers. Most flower stalls have two levels: the upper level is normally the point of sale, and the lower is the back-office. At this time of the day both levels are workshops.

flowerworkerb

I took a closer look at one of the persons rapidly putting together garlands. His hands are a blur to the camera. The man concentrated on his work, looking up only once to check me out. Since I was obviously not a customer, his attention was back on his job in a moment.

flowerworkerc

One man was clearly not in the Ayappa business for the rest of the day. He was rapidly churning out bouquets which look totally different, and could well be used in weddings. As I was taking photos, two young men came by in a scooter and started negotiating a large order for a wedding. Since this is the marriage season, the market must be pretty large.