Ever wondered why "sin" (of trigonometry) is called "sin"? Today, I decided to find out, and the history is fascinating. It comes from the Sanskrit word for bowstring which somehow got translated to the Latin word for the "pallu" of a toga.

Follow me down this rabbit hole 🧵 Let's start with this wonderful image I received from a friend on WhatsApp (source unknown). Here, you can clearly see why "tan" is called "tan". But what about "sin"?

If you think of the solid yellow arc as a bow, then the solid blue line (sine) is the bowstring 🧵

WhatsApp (if used well) is one the best things that has happened in communications in recent times.

It is excellent for deepening bonds with friends, relatives, and professional contacts.

But you have to work to ensure that WhatsApp doesn't degenerate into uselessness/toxicity By default WhatsApp can be too noisy and a distraction. Here's 4 things I have done to improve the situation significantly:

1. Surgical notifications
2. Ruthless exits from noisy large groups
3. Proactive creation of smaller groups
4. Polite policing

Rewriting my thread on #karmanyevaadhikaraste because it is important enough to get right

The first few tweets are a simple introduction and you can skip those because it will be familiar to most Indians

But the rest of the thread, the example applications, are the good stuff Bhagavad Gita, chapter 2, verse 47:

कर्मण्येवाधिकारस्ते मा फलेसषु कदाचन
मा कर्मफलहेतुर्भूर्मा ते संगोसत्वकर्मणि

You have the right to action alone, not to its fruits
Don't be motivated by the fruits, and don't get attached to inaction either

Good HBR article (by @TylerCowen et al) on reducing wastage and useless bureaucratic overhead from your hiring process.

Quick overview: /1 Do not have more than 4 or 5 "rounds" of interviews/interactions with a candidate. A study (at Google) showed that the first 4 gave 86% of the value. After that, the value diminished rapidly. /2

Voluntary student participation in your classes is higher if you're known as a teacher who randomly picks students to answer questions even if their hands aren't raised.

https://twitter.com/emollick/status/1546510485926862854

Some students don't participate because they're shy. Others because they have social anxiety.

This technique will work well for the former but ss Meeta points out, might make class worse for the latter

https://mobile.twitter.com/Meetasengupta/status/1546690694110031872

Did you know that a lot of hotels in India refuse to let a couple rent a hotel room if they don't look married? (i.e. if last name on Aadhaar card doesn't match).

For example, see:
thequint.com/lifestyle/taki… The problem appears to be widespread enough that a couple of hotel chains have made it their primary marketing pitch that they have no problems renting to unmarried couples. (Even OYO was using this line for a while)

1. Yesterday's budget announced that India will have a digital Rupee or a CBDC (central bank digital currency)

However, nobody really knows what India's digital Rupee will really be

A thread on why governments all over are considering CBDCs and what options RBI has looked at 🧵 2. First, what's a CBDC? Unfortunately, this is not a well-defined term and means different things to different people. But the basic idea is that it is a form of currency inspired by cryptocurrencies like Bitcoin but actually issued by the government and hence is "legal tender"

If you know someone on Twitter who:

1. Lives somewhere other than India/US/UK
2. Has >1000 and <10000 followers
3. Doesn't primarily tweet politics, and
4. Isn't a media person

Please let me know. I want to follow more such people. Expand my horizons. Reasons for the conditions:

1. Too much of my Twitter is focused on India/US/UK. Want to know how the other three quarters of the world lives
2. >1000 followers means they have interesting things to say, <10000 means they're not bland
3. Politics is boring to me

I'm not going to explain the meaning of IYKYK to you.

If you know, you know. Do you feel left out when people around you use acronyms like FOMO and you don't understand what they're talking about, and you worry you might be missing something interesting?

Storytel (the audiobooks + ebooks subscription app/service storytel.com) appears to have upgraded its collection.

Suddenly found a good chunk of my wishlist there and now have a very long reading/listening todo list

At ₹300 per month it is good value for money FYI: Storytel's collection includes fiction, non-fiction; has classics (e.g. One Hundred Years of Solitude; or How to Solve It by George Pólya) and new releases (e.g. Neal Stephenson's 2021 novel Termination Shock or Angela Saini's Inferior)

And regional languages (e.g. पु.लं.)

1. Everything that’s worth doing seems worthless and frustrating at some point. Learning about how to deal with this phase (called The Dip by @ThisIsSethsBlog) is something everyone should know about.

(Source for chart: bennadel.com/blog/776-the-d…)
🧵 2. I’ve found myself using this concept over and over again in the last 15 years when giving advice to people struggling with “what to do” choices. This includes everyone from high-school students to PhD aspirants to professionals with mid-career midlife crises.

1. I'm going to say this one more time:

You do not get jobs by applying through company websites or by uploading your resume on naukri or monster or writing to careers@company.com

You have to get your resume forwarded by someone in the company or known to the company 2. I had to give this advice to 2 people in one day yesterday. And I regularly have to give this advice to people from freshers to veterans with 20+ years of experience. So once more, loudly:

YOU HAVE TO GET YOUR RESUME FORWARDED BY SOMEONE IN THE COMPANY OR KNOWN TO THE COMPANY

1. The great promise of Aadhaar is (was?) associating a unique ID with every Indian which is very useful in real-life applications

But privacy advocates (rightly) complained of possible misuse.

The good news is: cryptographic algorithms can allow us to satisfy both requirements 2. For example DECO (deco.works) is a cryptographic protocol via which a person can verify their US Social Security Number to another person/company/website *without disclosing the number* to them.

The same should be possible to do with Aadhaar too.

Let me explain

1/ This fake resume getting past automated screens of big companies is going viral.

But, I think people don't understand how hard the life of recruiters is, and why such automation exists, so here's a thread presenting the other side.

https://twitter.com/Coding_Career/status/1454293034179317764

2/ Before starting, I should point out that I hate such automated keyword filtering tools. This is precisely why I co-founded @ReliScore with @aparanjape: so that companies can skip such automated filtering and directly move to testing for *relevant* skills.

But...

My code for @ReliScore is slowly falling for Greenspun's tenth trap, "Any sufficiently complicated program contains an ad hoc, informally-specified, bug-ridden, slow implementation of half of Common Lisp" as we implement automated eligibilty criteria for candidates Customers want to make candidates appear for different tests based on various criteria (branch, percentage, score on first round test, etc). And of course, I don't want to hardcode that. So I've ended up with a mini expression language.

And now there's classic score creep.

If a student in high-school is keen on a career in AI/ML, how should they prepare for it? What subjects should they learn, and what activities should they participate in? What basic subjects should you be strong in if you're interested in a long-term career in AI/ML? The replies to the parent tweet show that there are many different opinions.

Here's a thread on the slow and steady method, which focuses on building foundations for the long term.

1. Ransomware attacks are increasing. Even small companies in Pune/Bangalore have faced huge losses, in some cases coming to the brink of shutdown because of ransomware attacks

This danger is not really appreciated by people, so I wrote an article about this with @rohit11's help 2. There was a severe fuel shortage all along the US east coast last week. This was caused by a ransomware attack on the computer of the largest gas pipeline company in the US. The pipelines were shut for 5 days, and they ended paying $5 million in ransom

https://twitter.com/BarrettWilson6/status/1392169626780512258

1. There are videos floating around on WhatsApp implying that Bhramari Pranayama (yogic breathing/humming) can protect you from Covid. I would like to poke holes in that theory and hope that a real expert (@bhalomanush?) will also chime in. 2. The claims start by talking about SaNOtize, a Canadian nasal spray that releases NO (nitric oxide) in your nose and claims to be a "prevention and early-treatment for Covid-19". Then they point out that bhramari increases NO naturally. Thus implying bhramari prevents Covid-19

The Utah government paid $20 million for an AI software that scans social media posts and identifies criminal activity in real-time.

Due to some problems they had to start an investigation: is the AI racially biased?

What do you think they found?

I love this story, so a 🧵 /1 Before you read the rest of this thread, try to guess what the investigation found in response to the question: Is the AI algorithm racially biased?

I bet the answer will surprise you.

But let me tell the whole story first. /2

1. "There is too much variability in our hiring process," says the business leader. "Depending on which interviewer they get, people with very different skills get hired. Your tool will help us standardize."

Supposedly the customer is always right, but this is where I push back 2. I feel like wisecracking: if our software outperforms your employees, you need better employees

But I know that's not true. They are usually good employees who need to be given better training

Did you know that all the nuclear bombs we exploded in the '40s-50s-60s have permanently contaminated all the steel the world has produced since then? All steel in the world is divided into two categories: pre-1945 non-contaminated steel, and post-1945 contaminated steel.

How? Nuclear bombs (including the tests) create a lot of radioisotopes that are not found in nature. For example Cobalt-60 (a radioactive version of Cobalt-59). And since the 1945 Trinity test, these have all dispersed in the atmosphere.

What does this have to do with steel?