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Ask HN: What are some problems solved in unrelated domains?

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Re: Ask HN: What are some problems solved in unrelated domains?

#71

Contrary to popular belief problems solved in unrelated domains are very common in invention and innovation but people just hate to admit them, hopefully in the near future someone can honestly write a book on it. One of the most prolific scientists Albert Einstein had his single most productive year while working as a patent officer (Annus Mirabilis). I strongly suspect that he learned quite a lot from many patent a…

There's a fair bit of disagreement about how much CSIRO actually achieved rather than simply being the first to patent. The Wikipedia page is probably a better source than ars.

https://en.wikipedia.org/wiki/CSIRO#802.11_patent

Re: Ask HN: What are some problems solved in unrelated domains?

#74
Second order differential equations, they seem to pop up everywhere. Particularly relevant to classical mechanics. Also gives rise to the metal model of second order consequences of actions.

The concept of bootstrapping. How to start something from nothing that eventually becomes self sustaining.

Compound interest and exponential growth. Particularly relevant to investing as well as the personal ‘growth’ mentality. The natural exponent that was discovered from compound interest is everywhere in mathematics and physics.

Re: Ask HN: What are some problems solved in unrelated domains?

#75
post #7

Kanban comes from the automotive industry, and works really well in the tech industry. The Toyota Production System is a brilliant set of principles and practices that fit well in most industries. Toyota sent engineers to optimize street kitchens some years ago. ISO 9001 was implemented in manufacturing, and is quite popular in many circles of hell.

When I researched this I found that automotive Kanban bore absolutely no relationship to the computing industry's Kanban. Shigeo Shingo's book ( https://www.amazon.co.uk/dp/0915299178/ ) is particularly emphatic that Kanban was a was for repeatable industrial processes and not, for example, for knowledge work. Automotive Kanban is not a "Todo"/"doing"/"done" board, by his account anyway. The tickets sat on individual…

> It was about limiting the number of unfinished work items (which take up space and can be a sign that something is out of control).

As it happens, limiting unfinished work items (aka WIP) boosts software development productivity as well. The space being taken up is mental, but is also a bad sign of things spinning out of control.

Re: Ask HN: What are some problems solved in unrelated domains?

#76
post #14

The black-scholes model for pricing options had a big impact on the financial industry, and the big breakthrough for solving the equation was to realize it could be turned into the heat equation that already had a solution. If I remember well, the insight came to Robert Merton, an economist who had also studied engineering mathematics. https://en.wikipedia.org/wiki/Black%E2%80%93Scholes_model

"Big impact" is understating it. It's caused at least one financial crisis when Scholes and Merton's hedge fund ( https://en.wikipedia.org/wiki/Long-Term_Capital_Management ) went boom in the late nineties. Since then the assumptions present in Black-Scholes and similar pricing models have caused considerable chaos elsewhere in finance. One of those things that perhaps it would have been better that they had not inve…

It's also led to lower costs in just about every industry due to the ability to price obscure contracts and lower risk. An example is airlines need to deal with fuel price volatility when selling tickets now, and, if they take on more risk, they need to price that into tickets. Getting someone to hedge against that lowers their risk. The pricing of such hedges and contracts has led to less volatility for pretty much every industry.

For about a decade, as I flew a lot, I met a lot of mid level executives at all sorts of companies. I routinely asked them to describe if their company used any derivative products, and which, and why. I was astounded to learn pretty much everyone did, from pricing plastics, to dealing with international trade variations, to getting financing for projects.

There is a reason the derivatives market has a notional value of ~1 quadrillion, and it's not because the people using them are all idiots. Quite the contrary, this value is there because it adds value across every sector of the world economy, and business the world over voluntarily use these products because they deem it in their best interests, which almost universally is because it lowers costs and/or volatility.

This [1] claimed 94% of the world's biggest companies used derivatives, and this was in 2009. I'd expect more and more of them to use derivatives over time as more products get priced.

All this followed from the ideas in Black-Scholes, for pricing certain contracts, ideas which were later developed to handle all sorts of products. Before this, people did a lot of the pricing mostly by guesswork, making it much harder to design and use all these volatility reducing products.

[1] https://derivsource.com/2009/04/23/over-94-of-the-worlds-lar...

Re: Ask HN: What are some problems solved in unrelated domains?

#77
post #14

The black-scholes model for pricing options had a big impact on the financial industry, and the big breakthrough for solving the equation was to realize it could be turned into the heat equation that already had a solution. If I remember well, the insight came to Robert Merton, an economist who had also studied engineering mathematics. https://en.wikipedia.org/wiki/Black%E2%80%93Scholes_model

"Big impact" is understating it. It's caused at least one financial crisis when Scholes and Merton's hedge fund ( https://en.wikipedia.org/wiki/Long-Term_Capital_Management ) went boom in the late nineties. Since then the assumptions present in Black-Scholes and similar pricing models have caused considerable chaos elsewhere in finance. One of those things that perhaps it would have been better that they had not inve…

> One of those things that perhaps it would have been better that they had not invented.

I think you're off base on this. The ensuing financial mishaps just made the model better, but the creation of Black-Scholes brought us from 0% to 90% of the way to where we are today, where modern derivatives insure product price swings for almost everything across the world. Since then, a patch-work of model changes have brought us closer to perfect pricing through the realization that many markets have higher kurtosis.

Re: Ask HN: What are some problems solved in unrelated domains?

#78
post #14

The black-scholes model for pricing options had a big impact on the financial industry, and the big breakthrough for solving the equation was to realize it could be turned into the heat equation that already had a solution. If I remember well, the insight came to Robert Merton, an economist who had also studied engineering mathematics. https://en.wikipedia.org/wiki/Black%E2%80%93Scholes_model

"Big impact" is understating it. It's caused at least one financial crisis when Scholes and Merton's hedge fund ( https://en.wikipedia.org/wiki/Long-Term_Capital_Management ) went boom in the late nineties. Since then the assumptions present in Black-Scholes and similar pricing models have caused considerable chaos elsewhere in finance. One of those things that perhaps it would have been better that they had not inve…

LTCM's blowup had nothing to do with any flaw in Black-Scholes. They did lose money on equity volatility strategies but it was because they were betting that volatility in the future would be lower than the volatility implied by Black-Scholes. Volatility ended up going up and they lost money. They lost money because their forecast of volatility was wrong, not because Black-Scholes was wrong about the market's view of volatility.

Re: Ask HN: What are some problems solved in unrelated domains?

#79
post #27

Earlier quoted context omitted.

My wife said to me yesterday "How do I use a QR Code?". Keep in mind, she's a civil engineer and one of the smartest people I know. I said "In what context?" because really, I didn't know either. "I have to scan this QR code if I go to my office. It's apparently posted at the door, and will let them know I've been there, for contact tracing." After a lot of playing around, we finally found out her phone's camera coul…

It sounds like you aren't a fan of the way this QR code was used. I went to a restaurant the other day and it had one of those Coke Freestyle soda machines. There was a QR code on the screen which I scanned with my phone. This opened a website with drink choices. I put my cup under the dispenser and pushed the Barq's Root Beer button on the website on my phone which dispensed the drink from the machine. I was impress…

In Denver, I've seen many restaurants that have eliminated their physical menu and switched to a QR Code at the table that brings you to their menu online. Not as nice, but definitely useful in these times.

Re: Ask HN: What are some problems solved in unrelated domains?

#80
post #2

A real popular one would be QR codes. They were initially created to track manufacturing processes in the automotive industry. And you know how it is these days...

I really like Apple's implementation of an animated secure QR code [1] for migrating data from one device to another. It looks like undulating point cloud, and it has no formal name (but is described in 2 Apple patents as an "invisible optical label")

[1] https://apple.stackexchange.com/questions/301563/what-is-the...

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