gear Let's design some spur gears MotivationI need to draw spur gears to make a picture look cool... and I want to make them viable. I vaguely remembered that the teeth are involute curves to circles, but why and what exactly? I need formulae! Why do I publish this online? I think it might be useful

internet Great Time Waster and that Sucking World I am learning about diamonds. No, I totally don't know why I need to know about them. They look very concocted to me. I learn them in blind faith that they will be key encapsulating concepts to simplify the view. So far I don't understand nor have I formed any

reading Reading: ZMM Several months later, I picked up this book again. During those several months, I had very brief bursts of productivity, but mostly I wasted time doing nothing. I noticed that I didn't remember what the story so far was. One forgets things really fast. I remembered that I enjoyed reading

mathematics Flyer's License What Tuji got in first passTo get a permit to fly flying saucers one needs to master all of its manoeuvres. The possible manoeuvres are constrained by the structure of the configuration space [space parametrising location+orientation of vehicle]. A certain form on the contact manifold dictates that it can

mathematics Exponential Function Tuji's accountIn the beginning, we wanted to multiply number by itself many times. We produced a*a*...*a. Then we made a short hand an where n is a positive integer. After making a-1 to mean the inverse of a and a0 to be the unity 1, we found that

mathematics Homeownership After a brief scan of the word 'Homeownership', Tuji autocompleted it to 'Homeomorphism'.

mathematics Writing a friggn proposal If given complete freedom, I would set up some preliminary notation, explain the problem while referring to past endeavours and achievement of many people and potential application and relation to others work and suggest future direction of research in an organic fashion. Well, hell no in reality. I need to

mathematics Shopping FINALLY I ditched my Trump wallet. I got a new wallet and bantered a bit with the shop owner on wallets, mathematics and humanity. Apparently I know nothing about wallets except that those look great and feel great. We view maths as exploration with myriads of ways to approach problems

tags Tags Yesterday I went to a talk because I was attracted by the topic. The title contained the combination of names of two mathematicians which signified that we probably studied the same objects or, to a less extent, related objects. I wonder if research is mainly about giving good tags to

division The division symbol Tuj stared at the symbol, ÷, lost in thought. The first thought was that he had not seen it for ages. The second thought was that it actually conformed to the pattern of notation like f(·) = h(x, ·), H(G,·), (·,·)... ÷: Q × Q → Q (x, y) → x/y

talk What was I looking at? So I gave a talk and then received some photos of me giving the talk. I was aware that I lost the audience about 1 minute into the talk, my heart sank and the rest of the time I was not totally conscious. On the one hand, I am not

teaching Where did my female students go? It is embarrassing to report that I have lost all my female students after two lectures. ;_; What did I do wrong? (Was the fault entirely mine?) This is a delicate topic, extremely easy to offend people. I have a conjecture that my female students disliked challenges. Offence made. ;_; Please talk

teaching Teaching We sat down to prepare as we are going to teach some theory. That was overwhelming. We understand the theory pretty well, because we use it on a daily basis. However to teach it, we needed to pick a way to present it. That was really exacerbating when you could

happiness A Happiness Model There are many aspects of life that contribute to one's well-being, such as food, housing, income, community... Suppose that each of these can be quantified. People rate these and get a vector in the real space of aspects of life. Then people combine the results into something that may be

mathematics Modular Forms and Automorphic Forms What makes the theory of automorphic forms more complicated is the lack of names of individual elements. For modular forms, one can label all the various congruence subgroups as $\Gamma(N)$, $\Gamma_1(N)$, $\Gamma_0(N)$; one can label the Hecke operators as $T_p$-operators, diamond operators $$, Atkin-Lehner

feelings That which underlies We have been dawdling mostly. Still we read a paper, which may not be the best of choice for the present us. It explains a phenomenon of repeated systems of eigenvalues by means of action of an object whose existence is still a mystery even though whose manifestation is known.

mathematics Seminar We did not write summaries of seminars for several days. There was a talk about swapping to a good Shimura variety to do computations. It was not clear to us what the idea of the proof was. Have we talked about this already? Then there was a talk about Eisenstein

mathematics Staring into Black Hole, Changing to a Sensational Title First thing first, the speaker taught us how to write German letters to avoid any confusion. He obviously had that person who could not distinguish the letters p, y and g from last time in mind. Then began the lecture proper. It was all about how automorphic forms play a

mathematics Today's Lecture The speaker continued his talk of relative trace formula. The relative trace formula in itself consists of two ways of expressing a period integral of a kernel function. On the spectral side, one computes the contribution from each representation. On the geometric side, one computes the contribution of orbits of

mathematics Lectures The lecture began with the speaker finishing what she did not finish last time. We had forgotten about why we did what we did last time. It was all about a complicated construction, but we were quite lost on its use. Thus we stacked the idea away. The next speaker

git A new post-receive and Lecture Today we automated updating the database after git pushing to the server... It did not go smoothly. We learned how to use read to read in variables from a file. To guard against ourselves, we checked the variable names for matches before assigning. To make the shell file simpler, we

trekking Walking and walking We found ourselves in a house in the middle of a beautiful place with a hungry stomach. There were the white fluffy clouds, the golden sunshine, the translucent blue sky, the gently shuffling leaves, the sprawling meadow... except that there was no food. Then started our 30-minute trekking towards the

mathematics An Application of Path-connectedness We tried to get into a building to study, but the door was locked. Then we mapped out how this building connected to other structures at a local scale and tried various other doors to other structures. Finally we located an unlocked door and navigated into our desired building. We

mathematics Talking about Our Work We walked the trails in the morning. It was a little bit misty. The golden sunshine gently sifted through leaves that were shedding their verdant colour. The topic drifted into our past work. It was mostly hard work, laden with agony, yet sprinkled with moments of joy. We have navigated

mathematics Lunch and Lectures We were roaming. We went to lunch and unabashedly sat down at a French table. We talked about various things, including the haunting topic of job-searching. ;_; Then we went to lectures. The first one basically computed Fourier expansion of Eisenstein series. Armed with a version for higher rank case, we