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    1. Where to check and submit game length times?

      I was wondering where one can find (and submit) how long it takes to finish a game. After a quick online search I did find one or two pages where petiole post this, but none looked really good. So...

      I was wondering where one can find (and submit) how long it takes to finish a game.

      After a quick online search I did find one or two pages where petiole post this, but none looked really good. So I'm wondering if more regular gamers here have a recommendation.

      11 votes
    2. A layperson's introduction to Thermodynamics, part 1: Energy, work, heat

      Intro Hello everyone, @wanda-seldon has been giving us an introduction to quantum physics. For now, she will be given a short break to prepare new stuff. In the meantime I will be covering some...

      Intro

      Hello everyone,

      @wanda-seldon has been giving us an introduction to quantum physics. For now, she will be given a short break to prepare new stuff. In the meantime I will be covering some classical mechanics, more specifically thermodynamics. In part 1, we need to work our way through some of the more dry concepts, so we can understand and appreciate the horrifying implications of the fun parts. So I promise, this will be the most verbose one.

      Some of you may have briefly seen a version of this posted, that was due to me misunderstanding the schedule with @wanda-seldon. If you saw that one, I will mention I rewrote nearly all of it to be more readable.

      Now, on today's agenda: The basics of heat, work and energy and how it's all related.

      Previous posts can be found here: https://tildes.net/~science/8al/meta_post_for_a_laypersons_introduction_to_series

      Important note

      If @wanda-seldon in her posts mention "energy", it's most likely in the context of energy operators, which is a concept in quantum physics. I'm not going to pretend I understand them, so I will not be explaining the difference. We will cover what energy is in classical mechanics. So keep that in mind if you read something from either of us.

      Subject

      Summarized

      What is heat? Using a lot of fancy words we can describe it as follows. Heat is an energy that is transferred between systems by thermal interaction. And what is work? Work is an energy that is applied in a way that performs... work. The combined energy in a system is called internal energy. This type of energy can be transformed or applied to other systems.

      These are a lot of new words, so lets break that down a bit.

      Systems

      A system is just a catch-all term for something that can be defined with a boundary of sorts. Be it mass, volume, shape, container, position, etc. A canister, your tea mug, the steam inside a boiler, your body, a cloud, a room, earth, etc. They are all systems because you can in some way define what is within the boundary, and what is beyond the boundary.

      In theory, you could define every single nucleid in the universe as an unique system. But that would be counter-intuitive. In thermodynamics we tend to lump things into a system, and treat it as one thing. As opposed to Quantum stuff that looks at the smallest quantity. Calculating every single water molecule in my coffee would be pure insanity. So we just treat my mug as the boundary, and the tea inside the mug as the system. And just so it's mentioned, systems can contain systems, for instance a tea mug inside a room.

      Energy

      Energy is some quantifiable property that comes in either the form of heat, work. It can be transferred to other systems, or change between the different energy types. An example of transfer is my coffee cooling down because it's in a cold room. That means heat has been transferred from one system (my mug) to another system (the room). Alternatively you could say my hot coffee mug is warming up the room, or that the room is cooling down my coffee. Thermodynamics is a LOT about perspective. An example of transforming energy types is when we rub our hands together. That way we convert work (rubbing) into heat. It's really not more complicated than that. An interaction in this case is just a system having an effect on a different system. So a thermal interaction means it's an interaction due to heat (like in the mug example).

      This brings us to an extremely important point. So important, it's considered "law". The first law of thermodynamics even. Energy cannot be destroyed, it can only change forms.

      Your battery charge is never really lost. Neither is the heat of your mug of coffee. It just changed form or went somewhere else. The combined energy of all types that is residing inside a system is called internal energy.

      Heat and work

      Let's say we have a system, like a room. And all windows and doors are closed, so no energy can leave. In this system, you have a running table fan connected to a power line, getting energy from outside the system. The table fan is making you feel cool. Is the fan cooling down the room, heating up the room, or doing nothing? Think about it for a moment.

      http://imgbox.com/CKtQLLOQ

      The first thought of many would be to think that this fan would cool the room down, it sure makes you feel cooler! But it's actually heating up the room. As we remember, internal energy is the energy inside a system (room, in this case). The fan is getting energy from outside, and uses this energy to perform work. The fan accelerates the air inside the room, and this accelerated air will evaporate some of your sweat, so you feel cool. But as we remember, energy cannot be destroyed. So we are importing energy into the system, increasing the internal energy. Some of the work from the fan is also directly converted to heat, since the motor of the fan will get hot.

      So if we are not getting rid of any of this excess energy, we are increasing the internal energy. And therefore actively increasing the temperature of the room.

      http://imgbox.com/SAtqk7YG

      To use a more tangible example: Simplified, this phenomena is why green house gases are bad. Lets define earth as a system. Earth gets a lot of energy from the sun. And a lot of this energy will be reflected and sent back to space. Green house gases will reflect back some of this energy trying to leave earth. So instead of having a roughly equal amount of energy enter the system (from the sun, from us doing stuff, etc) that leaves out in space, we have an increasing amount of energy on earth. This, as a consequence, increases temperature.

      Implications

      Now, what are the maybe not so obvious implications of this?

      Waste heat, from supplied energy or inefficient work is a constant headache in engineering. If we cannot remove enough heat, we will actively heat up objects until they are destroyed. Thats why good cooling systems are important in cars, computers, etc.

      Whats next?

      Now this was not so bad. In the future we will cover phase changes, equilibriums, entropy, the heat death of the universe and briefly touch upon engines. So thats most likely two more parts after this. After that @wanda-seldon will take over again.

      I plan on doing one main part per week, but if something is asked that warrants a small topic I might do smaller ones inbetween.

      Feedback

      Something unclear? Got questions? Got feedback? Or requests of topics to cover? Leave a comment.

      19 votes
    3. An error message in Windows 10 is a mistake from 1974

      @foone🏳️‍⚧️: It is 2018 and this error message is a mistake from 1974.This limitation, which is still found in the very latest Windows 10, dates back to BEFORE STAR WARS. This bug is as old as Watergate. pic.twitter.com/pPbkZiE57t

      Twitter: foone🏳️‍⚧️
      32 votes
    4. Note-taking, bookmarks, reminders and todos: What do you use to organize your life?

      I find myself on a bit of an unending quest to organize my own thoughts, especially since my work evolved into multiple streams on different projects. I have been looking for a tool to help me...

      I find myself on a bit of an unending quest to organize my own thoughts, especially since my work evolved into multiple streams on different projects.

      I have been looking for a tool to help me organize myself and focus on the things I want to do. More specifically, I keep wanting to improve my ability to remember things: Be able to remember faster, longer, recall more reliably, categorize, filter and export those things, etc.
      Links, reading material, "watch later" material, todo lists, contacts, phone numbers/emails, identities, what I know about people, reminders, highlights, emails to respond to, work logging, etc. The more I think about it, the more I have this need for a tool that essentially acts as a permanent second brain.

      I feel like I've tried everything. Note-taking apps like Keep, orgmode, wikis, journals, disorganized text files, issue trackers, Pocket, gmail itself, calendar reminders, even Magic. Nothing quite works. The issues I most consistently hit are:

      • The method is not good enough at ingesting abstract data. Examples: Anything calendar-bound is not good at storing anything that isn't related to a point in time. Pocket cannot store things that aren't links to web pages.
      • The method is far too cumbersome to be able to braindump into it or too impractical to retrieve data from. Examples: Wikis, Keep and other object-based note-taking systems are unfilterable unless you take a ton of time to attach a lot of metadata to each note. Magic is too asynchronous as you sometimes wait several minutes for responses (and it also gets far too expensive to use at the level I'd like).

      Despite trying everything, I don't know if I want to build that tool myself, because I think it probably already exists somewhere (and it might be down to me not knowing how to use the things that are already out there). Although if someone does feel inspired to build that, hit me up. :)

      My current flow looks like a frankenstein mix of Keep/Gmail/Calendar, which at least integrate with one another, and a ton of proprietary or dissociated methods (including Pocket, Discord, Spreadsheets/Drive, Magic, Kayak, 1Password and a ton of duplicate files and documents). Then it just becomes a matter of remembering what type of information is where, and how to best find it.

      So Tildes, what do you use?

      23 votes
    5. nil

      I'm rather sleepy, generally very reserved when it comes to sharing my work, and not a native user of English, but I have a couple poems in English, and I though I'd share one here and see what...

      I'm rather sleepy, generally very reserved when it comes to sharing my work, and not a native user of English, but I have a couple poems in English, and I though I'd share one here and see what the folks think of it. I love the challenge of writing stuff in languages other than my native tongue.

      a bird with no wings
      a song no one sings
      a sorrow when time brings
               nil.
      ex nihilo nihil fit
      et words have no wit
      mouth knows only to spit
               nil.
      time is scarse and gods wobble
      in vain hurry naive men hobble
      ignoring they will only nobble
               nil.
      
      12 votes
    6. If human population stops rising or decreases, what will be the negative effects for people?

      From the environmental standpoint shrinking of human population is often quoted to have desirable effects, and that's reasonable. But from the point of view of our daily lives and functioning of...

      From the environmental standpoint shrinking of human population is often quoted to have desirable effects, and that's reasonable. But from the point of view of our daily lives and functioning of the human society, what negatives could we then expect? (I mean a soft decline due to lower birth rates, not some abrupt events.)

      For example, with smaller population fewer music albums could be made every year than some time before, and people would maybe feel less inspired and satisfied. Less scientific research, less choices for relationships... and maybe other things? Would being more technically advanced compensate for the issues? Won't we feel ourselves in oblivion and romanticize the "numerous" past?

      15 votes
    7. Which social media design features you find to be pet peeves?

      Most social media users enjoy some design features and dislike others. However, there are often things that, while minor, significantly worsen these users' experience. What are your social media...

      Most social media users enjoy some design features and dislike others. However, there are often things that, while minor, significantly worsen these users' experience.

      What are your social media design pet peeves?

      19 votes
    8. What have you been watching/reading this week? (Anime/Manga)

      Making the thread before I fall asleep edition. Anyway, what have you been watching/reading this week? Feel free to talk about something you saw that was cool, something that was bad, ask for...

      Making the thread before I fall asleep edition.

      Anyway, what have you been watching/reading this week?

      Feel free to talk about something you saw that was cool, something that was bad, ask for recommendations, or anything else you can think of.

      If you want to, feel free to find the thing you're talking about and link to its Anilist, MAL, or any other anime/manga database you use!

      9 votes