• 7 Posts
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Joined 1 year ago
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Cake day: June 29th, 2023

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  • We know something is out there; galaxies are rotating far too quickly for our understanding of gravity to be correct. This is based on the observable matter.

    For the galaxies to be rotating at the speeds we observe, we need approx 5 times the matter we see. So it is not like we have missed 10 - 20% of the matter that interacts with electromagnetic radiation, we would have had to have missed an extra 500%

    As someone else pointed out, MOND is the next most promising candidate, but it has major issues even explaining what we see. Which is why it hasn’t received widespread acceptance.

    I don’t have an answer; I have a few ideas. It maybe that something MOND adjacent is the answer; i.e. on the largest scales spacetime “relaxes” more when there is nothing pulling on it. So near galaxies and clusters spacetime is under more stress, this stress could equate to spacetime curving more on galaxy sized scales. But on the small scales we work on the extra stress will be almost invisible.

    But as for us figuring out what “dark” matter is in your lifetime, unless you are already in your 80’s; I think there is a very good chance. The only thing we know for sure about dark matter, is that it interacts with gravity (spacetime). We are building some pretty epic gravitational wave detectors, bringing the detection threshold lower.



  • If cosmic inflation is correct, probably not. Inflation is our best theory of the beginning of the universe.

    According to inflation, spacetime expanded exponentially from an infinitesimal point to many billions of light-years across. As far as we can tell, the universe is expanding again but at a much slower rate, due to dark energy.

    Spacetime survived the inflationary period, so it looks like it doesn’t have a “tear” mechanism.

    Another way to think of it, is to assume once torn, what is it tearing “into”. If you rip a bit of fabric, you look through to the other side, nothing special. If you tear our 4-dimentional spacetime, what are you looking at when you look “through” the ripped portion? This implies that out 4D spacetime is somehow existing in a higher dimensional reality.



  • Good choice on Mint.

    I have been using Linux exclusively (personal) since 2008, distro hopped for a few years then settled on Ubuntu, until they shot themselves in the foot with 22.04 and the snap debacle; moved to Mint (after trying Pop, MX and a few others).

    I have to say a big well done to the Mint devs, it is better than Ubuntu ever was; part of this is newer drivers etc…but it is very polished and it gets out of my way and lets me do my work.

    Been working with the various flavors of Windows in a work capacity over the same stretch, in my opinion windows peaked with XP, 7 was ok, and 10 is also ok. But it really has been down hill since XP was retired.



  • absGeekNZ@lemmy.nztoFuck Cars@lemmy.worldWalk-thru
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    12 days ago

    2007, Palmerston North, New Zealand.

    So a while ago, and Palmy has always had a significant student population, ideas like; you can get a free feed at maccas by going through the drive through and walking / biking off; tend to spread quickly.



  • absGeekNZ@lemmy.nztoFuck Cars@lemmy.worldWalk-thru
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    13 days ago

    When I was at university, I used to ride my bicycle to the local 24hr Macdonalds after I finished work; around 12:30am, I’d arrive just before 1am.

    After doing this for ~8 months, they must have changed the policy, I was no longer able to use the drive through. But the door was locked after 10pm, so no more late night snacks for me!

    Not sure if motorbikes were allowed or not.