Hi, I’m Shauna! I’m a 37 year old transgender woman from Ontario, Canada. I’m also a Linux enthusiast, and a Web Developer by trade. Huge Star Trek fan, huge Soulsborne fan, and all-around huge nerd.

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Joined 1 year ago
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Cake day: June 15th, 2023

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  • It’s definitely an edge case by say you’re in ~/ and you run a script like ./code/script.sh then it thinks the current working direct is ~/ rather than what is probably intended which is ~/code/. If your bash script uses full paths like /home/$USER/code/ then it will still run correctly regardless of the current working directory that the scrip was run from.


  • That’s true of any galaxies which aren’t gravitationally bound. At closer distances (tens/hundreds of millions of light years) gravity wins out over the expansion of space and keeps things together. At larger distances, the expansion of space wins out and clusters of galaxies will drift apart faster and faster until the combined speed of them moving away and us moving away from them will exceed the speed of light and we’ll never see those galaxies again.

    Our neck of the woods is called the Local Group because scientists are bad at naming things and includes the Milky Way galaxy, and the Andromeda galaxy, as well as between 50 to 80 more galaxies.

    As for the black holes, yes, eventually all that will be left are black holes for trillions of years until even those evaporate which is often called the “Heat Death” of the universe. That is just a theory, but if it’s true, it won’t happen for 1.07x10^106 years. Considering the universe is only 13.8 billion years old right now, that’s a very, very, very long time.



  • I’m not a professional, but just an enthusiast but I’ll try to simplify the article from my layperson perspective, so take my interpretation with a grain of salt.

    The new theory seems to point to how Einstein’s theory of gravity considers the “energy-momentum tensor” to be unchanged in all scenarios. The energy-momentum tensor describes the relationship of energy as it changes between various forms, for example a stick of dynamite exploding changes the chemical energy stored in the dynamite into kinetic energy - the force of the explosion - and if you calculated the energy of both they would be equal to the initial chemical energy stored in the unexploded stick of dynamite. Which is called the “law of conservation of energy”, that energy cannot be destroyed, only transformed into a different form of energy.

    The problem arises in high-energy situations where infinities start to appear in the equations. If you know much about math then infinities can break equations, and often in physics if there are infinities appearing in your equation then it usually means that you’re missing something crucial. So scientists can use a technique called renormalization which can apply tweaks to equations to reduce these infinity spikes. At these high-energy situations described, renormalization fails and the equations can’t be properly satisfied no matter how you tweak the variables. This is a big problem since a correct theory should be able to come up with answer for all possible situations that might arise within the system it’s trying to describe without breaking.

    Einstein’s field theory - which is a model used to describe spacetime based on the distribution of matter within it - uses the curvature of spacetime, the relationship between stress and energy, and the cosmological constant. The new theory proposed suggests that adding to Einstein’s field theory with math that accounts for the relationship between temperature and entropy, and the relationship between charge and interaction changes the equation in such a way that the infinities disappear, even at higher energy levels which traditionally break field theory, and most importantly that it’s still consistent with observations.




  • You need to learn bash scripting. Also, there are a few default files that the .bashrc uses which can be helpful to compartmentalize the custom things you do to it so that it’s easier to undo if you screw something up. To do that, just add this to the bottom of your .bashrc

    if [ -f ~/.bash_custom ]; then
        . ~/.bash_custom
    fi
    
    

    What that will do is check if the .bash_custom file exists and then run the .bash_custom file in your home directory and apply anything in there. Also, you can call the file whatever you like, but bash does have some defaults that it will check for and run them without editing the .bashrc at all. It’s kind of hard to find a list of the the files that it automatically checks for, but I know that .bash_aliases is one of them, and I think it checks .bash_commands as well, but I’m not entirely sure. Either way, you can force it to check your custom one by using the code above.

    Then you can create the file and add any custom things in there that you like. For example, I like to frequently update through the terminal but running sudo apt update && sudo apt upgrade && sudo apt autoremove && flatpak upgrade was a bit tedious and I wanted a bit less feedback so I made a custom alias for my personal use.

    alias update='echo "Updating packages..."; sudo apt update -y &> /dev/null; echo "Packages updated."; echo "Upgrading packages..."; sudo apt upgrade -y &> /dev/null; echo "Packages upgraded."; echo "Cleaning up packges..."; sudo apt autoremove -y &> /dev/null; echo "Packages cleaned up."; echo "Updating flatpaks..."; flatpak update -y &> /dev/null; echo "Flatpaks updated."'

    Which hides most of the text from updating and just gives me feedback on what it’s currently doing if I don’t really care to know all of the details. So now I just run update in the terminal and plug in my password and it updates and upgrades everything in a human readable way.

    There’s a lot that can be done with bash scripting, like editing files, iterating over files and directories, setting environment variables. It’s basically a full programming language so the limits are mostly your imagination.