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Cake day: June 12th, 2023

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  • It’s the renewables on the grid that have to make a difference. If you’re powering an electric car purely out of electricity generated with fossil fuels you’re effectively building a series hybrid with extra steps, with the combustion engine being outside of the vehicle. Or I guess you could also compare it to a diesel-electric locomotive with the generator outside the vehicle, which he also explained in the video would not be good for efficiency. And yes at the scale of power plants you can do some things more efficient, but it’s not actually that much as the efficiency is mostly limited by similar thermodynamic processes than that happen inside an engine. A typical coal power plant also has an efficiency of 30-40% (so effectively a mediocre coal plant is similar in efficiency to a very efficient engine, and yes, some new ones can reach higher efficiencies, but the vast majority still use an old design, at least around here). But when you get the energy from a power plant you still have distribution losses on the grid, conversion losses when charging the battery and again when discharging the battery, and the efficiency losses in the electric motor, while you do not have grid losses and charging/discharging losses and losses in an electric motor with a combination engine is directly driving the wheels.

    That’s why it’s important to keep investing in renewables. You indeed don’t need a whole lot of renewables to offset the efficiency losses of the battery and distribution, but you do need at least some of it. And you also should not just look at the grid as a whole, but at how the additional load of charging the vehicle gets handled. If all renewables on the grid are operating at maximum capacity all the time, and there is a coal plant that is used to burn extra coal when extra capacity is needed, then any additional load can be considered to be running on pure coal power even if the grid contains many renewable sources. But if you live in a neighbourhood where there is a constant overproduction of solar power while the grid and can charge your car at times of overproduction, then you effectively charge your car with fully green energy even if the grid contains a lot of fossil fuel plants.

    You can consider electric cars to be the infrastructure that enables the transport sector to become more green, but we do also need to actively increase energy generations via green sources to actually make use of that “infrastructure”. Though I guess there is also some good news: Powering an electric car from exclusively fossil fuel energy sources puts the efficiency of the full chain somewhere between regular cars and hybrids. So it should at least never be worse than driving a regular car. Worst case it’s just equivalent. But it does need investments in green energy sources as the demand on electricity increases to become significantly better.


  • I think the “80% after 1000 cycles” isn’t ambitious enough. 1000 cycles is still very easy to reach, and some phones already barely last a full day when new so even that 20% lost capacity can really degrade the experience. I’d argue that it’s not even an ambitious target at all, as even bog standard lithium ion batteries are frequently rated for that lifespan or more.

    I could understand it if they had an exception for potential future technologies that would be pretty much guaranteed to outlast the useful lifespan of the device (such as solid-state batteries which could in theory last for tens of thousands of cycles and thus last for decades, if it is ever able to leave the lab). But as it is now with the unambitious goal of 1000 cycles so many batteries will be exempt by default that I don’t think it’ll change much.



  • The total voltage or amperage of the battery pack does not mean anything for the battery cells. You can put more cells in series and get a higher voltage at lower current, or more in parallel and get a higher current at a lower voltage. But all individual cells will run at the same voltage in either configuration (iirc between 3 and 4V), and the current per cell will also be the same for a given load regardless of the situation.

    The main thing a higher battery pack voltage accomplishes is that the cables connected to the battery don’t need to be as thick, as the required thickness of a cable depends only on current, not voltage.



  • It’s not easy to scale up chip production, because it relies on extremely precise machines, which take a long time to build, and many different steps on the way from raw materials to a finished chip.

    If you’d want to set up a new RAM chip factory with competitive performance, it’d be an investment of over a billion USD at the bare minimum, and it’d take a few years to set up all the processes because the first chips can roll off the assembly line.

    If the bubble popped by then, then your new factory would probably run at a loss because it’s nearly impossible to complete with companies who have had decades to optimise their production processes.

    Even if the bubble didn’t pop by then, then the next problem will likely be the wafer supply. Because just like how there are only a few companies with the infrastructure to build modern, high-performance computer chips, there are only a few companies with the infrastructure to build silicon wafers of a high enough quality to build those chips with. And they have only just enough capacity to supply their current customers.

    So to then solve the wafer problem, someone needs to be willing to invest at least a few hundreds of millions of USD to build a new factory for those, which again would struggle to complete in a post-scarcity market. And wafers are far from being the only resource with that issue.

    TL;DR: It’s be a huge investment and a huge gamble, and would likely end up just moving the problem anyway.



  • Yeah, it’s not a miracle drug, but it does allow you to diet on easy mode. What you’re supposed to do while on the drug is switching to healthier food and healthier eating habits. The drug should make that easier as it should remove the cravings that you’d normally get from switching to less calorie dense meals, and if you’re eventually used to healthier meals then it should be easier to keep that up once you’re off the drug.

    But you do have to actively build those healthier eating habits while on the drug to get that lasting effect. It offers an easier way to switch to a healthier lifestyle, but if you don’t actually make that switch then the effect will indeed just wear off immediately once you stop taking the drug.


  • I am typing this on a 5 year old Android phone. It has 128GB of memory and 8GB of RAM, very decent cameras, a beautiful OLED screen and a processor that is more than fast enough for everything I do with it. And even now the battery still lasts two days with normal use. It cost me about €300 at the time.

    Unfortunately the Android version is getting so far behind that some apps are starting to get a few issues, so I have been checking out some black Friday deals for new phones, but they look very disappointing.

    In the current market it seems like I’d have to pay about €500 to effectively just get a side-grade. All €300 offerings look like just a straight up downgrade in any way apart from the more recent android version.

    So I think I’ll hold on to this one a while longer. Hardware-wise it’s still in perfect condition, and if software support really becomes an issue then perhaps I’ll try out a custom ROM.


  • The main reason is tech debt and proprietary software. Most companies have decades of software infrastructure all built on Microsoft based systems. Transitioning all that stuff to Linux is a massive investment, especially taking into account the downtime it’ll cause combined with the temporary decrease in productivity when everyone has to get trained and build up experience with the new platform.

    And then you have to deal with proprietary software. A lot of niche corporate or industrial hardware only supports Windows. And you probably have to regularly interact with customers who use Windows and share files with you that can only be opened in Windows only proprietary software.

    Linux also frequently struggles with a lot of weird driver issues and other weird quirks, causing an increased burden on the IT department.

    Basically you’re looking at a massive investment in the short term, for significantly reduced productivity in the long run. And all that mostly to save a bit of hardware costs, which are only a fraction of the operating costs for most companies. Just sticking with Windows ends up being the more economical choice for most companies.



  • In this case it’s somewhat different.

    We have seen almost these exact formations on earth, where they are created by microbiological lifeforms which could survive in the condition of how we expect ancient Mars was like when this sediment was formed.

    We have been able to reproduce similar patterns in the lab, but only in conditions with much higher temperatures or with much higher acidity than what we’d expect Mars to have been like back then.

    So the possible options are:

    1. Ancient Mars was how we expect it to have been, and these patterns were formed by ancient microbiological, Martian lifeforms.

    2. These patterns were formed by a known chemical process, and ancient Mars was much hotter or more acidic (or both) than we expected based on all other research.

    3. These patterns were formed by a currently unknown chemical process that does not require the high temperature of acidity that the known processes require.

    So in this case it’s not just wishful thinking. The hypothesis of this being formed by microbiological life is the hypothesis that best fits with what we currently know about the conditions in which the sediment was formed (which doesn’t fully prove that it’s true, but does give it credibility). And even if options 2 or 3 will end up being the right explanation, then we’ll still at least learn something interesting from this.





  • x86 has bit manipulation instructions for any bit. If you have a book stored in bit 5 it doesn’t need to do anything masking, it can just directly check the state of bit 5. If you do masking in a low-level programming language to access individual bits then the compiler optimization will almost always change them to the corresponding bit manipulation instructions.

    So there’s not even a performance impact if you’re cycle limited. If you have to operate on a large number of bools then packing 8 of them in bytes can sometimes actually improve performance, as then you can more efficiently use the cache. Though unless you’re working with thousands of bools in a fast running loop you’re likely not going to really notice the difference.

    But most bool implementations still end up wasting 7 out of 8 bits (or sometimes even 15 out of 16 or 31 out of 32 to align to the word size of the device) simply because that generally produces the most readable code. Programming languages are not only designed for computers, but also for humans to work on and maintain, and waisting bits in a bool happens to be more optimal for keeping code readable and maintainable.



  • Depends on viewing conditions. As of yet there isn’t an objectively superior display technology.

    OLEDs have the best contrast in a dark room as black pixels can be fully turned off, but they are generally less bright and use more power than comparable LCD TVs or monitors (especially when you compare models of a similar price range).

    LCD based monitors and TVs can get brighter and can actually achieve a higher contrast in a well lit room as the black pixels on an LCD are less reflective than black pixels on an OLED, and when viewing in daylight the ambient light is more than enough to drown out the backlight bleed.

    There are also other smaller pros and cons. OLED for example has a better pixel response time, while IPS LCDs are more colour accurate. Text rendering and other fine graphics also generally look slightly sharper on an LCD than on an OLED display (when comparing displays of equal resolution / pixel density) due to the subpixel layout.