I sail the high seas of the Lemmyverse, posting snarky + Lefty comments

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Joined 1 year ago
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Cake day: May 7th, 2023

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  • I’m a dev but not very good at mobile.

    I can promise you that a lot of engineering work went into making the tiktok scrolling experience so smooth. Part of the trick is having a good enough algorithm that the user wants to watch the majority of served videos.

    Another huge part of it is having lightning fast content distribution and aggressive “prefetching” of the next videos in the feed.

    I don’t want to discourage you but I also don’t want you to be caught off guard by the difficulty. Do you want to make this bad enough to give it your nights and weekends for a year?


  • Rail is fundamentally superior to roads + cars at an engineering level.

    All at the same time:

    • Rail has a smaller footprint

    • Rail moves multiple times more people or cargo per hour

    • Rail has multiple times more fuel efficiency

    The fact that USA’s policy has been designed to favor cars only makes them more ‘practical’ than rail if you consider political constraints more binding than physics constraints.

    I’ll grant that trucks have tighter turning radii and maximum operating grade. If we truly only used them when those characteristics are needed THAT would be ‘practical’





  • I did a little research and the answer is pretty interesting!

    Originally, chemists assigned hydrogen a mass number of 1, and used that assumption to derive the masses of the other elements. Today we definine “1” as being 1/12 of the weight of Carbon-12 (which is very close to the average weight of hydrogen we use today)

    As to the relative frequencies, they can be different at different points on earth, this Chemistry SE answer goes into a lot more detail.

    If you have never done “stoichiometry” before it may not be obvious but the periodic table average weights are essential for going from “I have x grams of substance” to “I have x number of atoms/molecules of substance” and from there you can use the equation of your target reaction to precisely predict the outcome of a chemical process. If you were doing very high precision chemistry, the differences in isotopic ratio in your sample vs the standard values could introduce an error but I would guess most of the time it is insignificant.












  • So…the US dollar is the world’s “reserve currency”. Most international trade is actually conducted in USD, and central banks have to hold billions of USD in reserve as part of their basic operations.

    This gives the US two massive geopolitical advantages:

    • Because central banks like to hold their reserves in US Treasury bonds (which are considered safe but also pay interest) it artificially lowers the interest rate on those bonds. It’s estimated this saves the US hundreds of billions of dollars annually in borrowing costs.

    • Unless you want to use literal truckloads of cash, the only way to obtain and hold USD is through the global dollar-denominated banking system, which itself MUST comply with US sanctions. In practice this means that the US can “sanction” individuals, companies and countries - and thus nearly freeze them out of global trade and finance.

    I think it’s best to see BRICS as a direct response to that reality. The more these countries trade with each other in their own currencies, the more they weaken “dollar supremacy”.

    Over time, (20 years?) I personally would predict that the effectiveness of the US sanctions will degrade to the point of irrelevance. You can already see this (IMO) in the “chip wars” and Huawei’s “escape”. I think the proportion of global trade denominated in dollars will steadily decline, and borrowing costs will start to normalize to the rest of the world, and possibly spike.