CAM Diaries: It goes over head now

 Three days of lectures have passed as quickly as these lavish bedroom in my CAM appartments  lulls me to sleep. Faster than Ismail Bhai's (for I can't properly pronounce the Ismaël Bailleul) words flew over our head. The darkness of ignorance is like in which I left NISER.  No तमसो मा ज्योतिर्गमय granted yet. The thing is this workshop is about solving certain singular parabolic heat type Stochastic PDEs with a novel renormalization technique developed by Fields Medalist Hairer. Phew. Long sentance. Knew it was out of my bounds much earlier. Ismail bhai thinks that it is the Hopf algebraic structure of Models and regularity which might be a problem. But that part sits well with me. My problem is the standard PDE ailment. Kesavan avoids in as does R sir, but they are outsiders to the field. So am I. Perhaps that point of view is what suits me. But I think a lot many "natives" are also lost in the workshop. LB most certainly is. This I know from our long walks. Other I talked to are in the same boat too. But even as an outsider, since I work in Corona Problem, PDE is an important tool in my toolbox. I have been in an search of the elusive proof Hall's Lemma.  There is an 1983 paper which derives it using Stochastic methods. Which was one motive to come here. But alas it didn't help directly. But now I feel now confident to actually tackle the '83 paper rather than cowering hearing Stochastic. Anyway random pics from the walk today. 

CAM Diaries: दिग्गज, दोस्त और दिव्यता

एक दिन वर्कशॉप का बीत गया। एक थोड़ा बहुत बस idea सा लगा कि क्या हुआ लेकिन कुछ ठोस नहीं। अब जिस विषय में क ख ग का ही अंदाज़ा ना था, उसमें यदि 2021 के पेपर को पेश किया जाए तो इतना भी बहुत बड़ी बात है। काम cutting edge है एकदम। और बहुत लंबा चौड़ा, तो ऊपर ऊपर से ही बताया जा रहा है। इस्माइल भाई वर्ता है, और कल रात पता चला कि मेरे ही साथ वाले कमरे में ठहराएं गएं हैं। नामी दिग्गज है, उनके पास रुकना ही तो सम्मान की बात है। मुझे भी एक आलिशान अपार्टमेंट मिला है। रूड़की के एक भईया के साथ मिला है लेकिन ये इसकी तो रसोई ही मेरे निजी के कक्ष से बड़ी है। निजी लैट्रिन है। खाना भी एक नम्बर है और सस्ता भी। काश 2023 में इधर मुझे ले लेते, दिल तो बस गया हे इधर। जाते वक़्त दुःख होगा। अब क्या ही कर सकते हैं। आस पास का इलाका भी शान्त साफ़ सुथरा है। सुबह शाम टहलने जाना भी एक Therapy है इधर तो। आज सुबह ही गली में एक सुन्दर का मंदिर मिला।

भव्य मंदिर होते हैं गली गली गंगापट्टी के बाहर। देखकर ही दिल में दिव्यता का अनुभव होता है।

वैसे तो इधर जो है मेरे काम से बाहर है। लेकिन आज और कल इस्माईल भाई बोले हैं कि कुछ tools develop करेंगे जो analysis में काम आएंगे। The mechanics of local expansion और Renormalised continuous models । अभी तो हवा तक नहीं की ये क्या है। देखते है भविष्य में क्या होता है । पलक्कड़ में गए थे और ज़्यादा सीखे नहीं, बुरा लगा था। इधर नहीं लग रहा लेकिन। LB के साथ खाना, चाय, घूमने का ही कार्यक्रम करते रहते हैं। पिछले 6 महीने छोटी सी कक्षा में पढ़े तो दोस्ती तो बढ़ गई थी, अब तो बिलकुल भाई बहिन ही हो गए हैं। अच्छा है। कुछ तो फायदा हुआ। लेकिन नहीं सीखने का प्रयास करना है, बिना टेंशन के लेकिन ।अब जाना होगा दूसरे Lecture के लिए। चलते हैं।

NISER to CAM with Azithromycin

 It's 3 am and it's pitch black inside. Skipped bath. Bath, irrespective of the water temperature - which anyone needs to be regulated by my induction for the geyser works in timming nobody knows and nobody can change - and duration, would have resulted in death due to my cold which have survived 5 Azithromycins. Still I must leave for the SPDEs workshop I have been talking of again and again. The car won't come to the hostel, for there is some nonsensical rule about gate timming which is sporadically implemented, perhaps the workshop will help with this knowledge. Yet in the half dead state I must push on, push on I must. 

Arrived at Bangalore, or Bangluru as one have to say it now. Flight was not at all how I assumed it would be. It was nice. While apparently sinus worsening in flight or Aerosinusitis is a real thing, in my case the pressure difference seemed to have made some nudges in the postive direction. Nah, not nudges, particularly potent proding it was. It am all but almost cured. The Banglore skyline, welcoming me for the third time (and second time when I am headed for CAM) camouflaged itself like the early November Delhi smog, minus the smoke. So yeah just fog. I almost forgot how nice it felt in childhood when we could experience pure(ish) fog. And the excellent BMTC and KIA brings me and the batchmate LB at the gates of TIFR CAM. 

Workshop starts from tomorrow, as does hopefully my learnings too. Now it's just unpack, wait, relax and watch.

Review: Topics in Functional Analysis and Applications

Topics in Functional Analysis and Applications by S. Kesavan
My rating: 4 of 5 stars

Despite the name, this is one of the better written PDE books out there. It treats partial differential equations as applications of functional analysis, and its handling of function spaces and operators is correspondingly rigorous. While this book came about earlier, it should be used in conjunction with Kesavans' Measure and Integration and Functional Analysis. When reading those two books, readers will find that there are certain results not normally available in books on Measure Theory of Functional Analysis, but which are used in this book. The only thing missing is that the new editions should directly refer to the said results in the other two books, rather than one frantically searching for the actual statement based on what one needs. The authour also has a NPTEL course, avaible on YouTube, to go with the book, but the quality of those I can't judge for I haven't watched the.

This (3rd) edition is the best one for me, the earlier editions, especially the first one Topics in Functional Analysis and Applications, have many many typos and omit several important topics. The latest (4th) edition retains all the typos and mistakes of the third, the main change is the typesetting, which is more "modern" and non-compact. Also, the price. Up 33% from 300 to 400. NO typesetting is worth that.

Still, there are errors in the books. Notably, in the section related to the Trace Theorem. One should refer to Krantz's (he does write on almost everything I need) Partial Differential Equations and Complex Analysis and McLean's Strongly Elliptic Systems and Boundary Integral Equations. The section on Sobolov Spaces should be supplemented with Real Analysis: Modern Techniques and Their Applications and the boundary Sobolev Spaces can be better learned from J-Holomorphic Curves and Symplectic Topology (COLLOQUIUM PUBLICATIONS (despite the Scary sounding title, I still haven't dared to try comprehend what title is about, the relevant appendix is self contanined and rigorous in treatment). Keeping a standard PDE reference such as Evans’ Partial Differential Equations at hand is also advisable, as one can easily get lost in the functional-analytic machinery and techniccalities.

In summaryt this is a good textbook for a secon course on PDEs with a Generlized Functions viewpoint. Moreso for people primarily working on hard analysis who view PDEs as a tool for their work and those who are fed up with the general lack of rigour in PDE books as a whole.

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Sanyal's Two Beers, a Few Laughs, and Many Abrupt Endings

Just finished reading "Life over Two Beers and other stories" by Sanjeev Sanyal. This is Sanyal's. better known for his non-fiction works and being in the PM's Economic Advisory Council, first attempt at fiction. He chose the medium for he laments the loss of short stories and satires in contemporary Indian literature. While I agree with his diagnosis, this collection of about fifteen short stories and a couple of poems is not the cure.

Most of the stories are set in modern metropolitan India, and the satire is mostly aimed at the buddhijeevis—the inhabitants of the IHC, the cultural-intellectual elite. While the undertone of satire is there, as Ashish Taneja' also notes, it is often too thin and difficult to appreciate. The stories are too short and the endings seem abrupt in most cases.

 Sanyal can be a delight to hear when talking of domains he knows of, like his talks on  Process Reforms. I think more important to appreciate is that he is actually carrying out the reforms and nit just an advocate for them. While I have not read his non-fiction, I have seen his lectures and debates. He even had a show called Economic Sutra on RSTV to basically sell the current government's reform agenda, but that seems to have been discontinued. I liked that. It was a good show for people who knew nothing of economics as well as those who keenly followed the public policy debates. But alas, Prasar Bharti works in mysterious ways. In the collection too, "Drivers" and other stories which focused on the side working of the government stood out. "Used cars salesman", "Bench by the lake", "The intellectuals" were also good. Ironically, tales not set in contemporary India fared better to me. "Revolution of Humour", "The Return of Imagination" and the "Conference Call" were in this category. The first two of the three were set in distant exotic lands in past times, which I felt the author had a real knack for writing such settings, more so than for portraying contemporary India.

Here is my GR review. I will not link the other way around as one would normally expect due to reasons noted previously.  The Harmonic exam went well enough in terms of marks (should one have just memorised the assignments, it was a 100/100 paper), and it is as a treat I reward myself with writing this post despite the Advanced PDE exam tomorrow. Not that I was 100% seriously studying for harmonic. I finished The Housemaid's Secret and read half of Sanyal's collection yesterday. Just one more day and the semester ends. The atipication kills one before, and relief afterwards.