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Cake day: July 7th, 2023

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  • “Our doubts are traitors, and make us lose the good we oft might win, by fearing to attempt.” ― William Shakespeare, Measure for Measure

    “It is possible to commit no mistakes and still lose. That is not weakness, that is life.” ― Captain Jean-Luc Picard

    “How much more grievous are the consequences of anger than the causes of it.” — Marcus Aurelius


  • One massive point that most people are completely blind to is that with energy considerations we are aggressively pursuing two very different goals that in many regards are directly at odds with one another.

    The first goal is electrification, which can largely be accomplished by increasing renewables, investing in battery technology, etc. But in the US, we have also been accommodating the desire for electrification by massively increasing natural gas capacity.

    The second goal is decarbonization. This requires us to also nix natural gas from the equation at some point. In addition to the problems others have already mentioned (like the fact that renewables aside from hydro are not viable base load power options right now), there is a significant chunk of our energy infrastructure that simply cannot be satisfied in any regard purely with renewables. Like the huge number of industrial processes that need process heat to achieve their end product.

    So the best solution is energy portfolio diversity. We can steadily continue to phase out heavy polluters for electrification, but if we want to truly decarbonize, industry demands a solution that can still produce high heat without emissions. Nuclear is a woefully under-exploited technology in that regard, but it is potentially a great solution.



  • Sure. Except “letting them evacuate” in this case is better characterized as “continuing to expel them from their homes under threat of violence.” I’m not arguing the 24 hour time period is the atrocity, I’m arguing the act of creating a humanitarian crisis under the auspices of a military campaign effort is abhorrent.

    It’s not like we don’t have any good reporting on the matter either. The BBC for example has already been attacked because they refused to declare Hamas as terrorists (a label I agree with, for the record). [This article](BBC News - Khan Younis: A Gaza city on its knees, now with a million mouths to feed
    https://www.bbc.co.uk/news/world-middle-east-67116403) provides some insight into the absolute horror regular Palestinians are going through right now.




  • This is one of the most commonly touted engineering myths that simply doesn’t hold up to even a brief analysis. The first glaring problem is the inherent survivorship bias behind claiming Roman concrete was objectively better than modern concrete. As other users have already mentioned, modern concrete is actually very strong and exceeds the strength of Roman concrete when such strength is required, but where it really has an advantage is in its consistency.

    If every concrete structure built in Rome was still standing and in good shape to this day, engineers would be salivating over the special blend and would be doing whatever they could to get their hands on it or replicate it. But we don’t see that. We see the Roman concrete structures that have survived the test of time (so far), not the myriad structures that have not. Today’s concrete on the contrary is deliberately consistent in chemistry, meaning even if it typically isn’t designed to last hundreds of years, you can say with a great deal of confidence that it will last at least X years, and all of it will likely exhibit similar wear and strength degradation behaviors over that same duration.

    There are other factors at play too:

    1. Romans didn’t use steel reinforcing re-bar, instead opting for massive lump sums of concrete to build structures. These massive piles are better against wear and porosity-related degradation, especially due to the self-healing properties of the Roman concrete blend due to volcanic ash helping to stop crack propagation.
    2. Our modern concrete structures are much, much larger in many cases and/or are under significantly higher loads. Take roads for example—no Roman road was ever under the continued duress of having hundreds of 18 wheelers a day rumble over them.
    3. Our modern concrete structures do things that would have been considered witchcraft to a Roman civil engineer. Consider the width of unsupported spans on modern concrete bridges compared to the tightly packed archways of Roman aqueducts.

    None of this is to detract from Roman ingenuity, but to make the claim that Roman concrete was objectively better than what we have today is farcical.