• 7 Posts
  • 16 Comments
Joined 1 year ago
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Cake day: June 12th, 2023

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  • I think Schneier wrote this well before quantum computers were a reality - did he miss something fundamental in regards to them? Quantum computers are relatively new but the theory behind them is nearly a century old.

    *One of the consequences of the second law of thermodynamics is that a certain amount of energy is necessary to represent information. To record a single bit by changing the state of a system requires an amount of energy no less than kT, where T is the absolute temperature of the system and k is the Boltzman constant. (Stick with me; the physics lesson is almost over.)
    
    Given that k = 1.38×10-16 erg/°Kelvin, and that the ambient temperature of the universe is 3.2°Kelvin, an ideal computer running at 3.2°K would consume 4.4×10-16 ergs every time it set or cleared a bit. To run a computer any colder than the cosmic background radiation would require extra energy to run a heat pump.
    
    Now, the annual energy output of our sun is about 1.21×1041 ergs. This is enough to power about 2.7×1056 single bit changes on our ideal computer; enough state changes to put a 187-bit counter through all its values. If we built a Dyson sphere around the sun and captured all its energy for 32 years, without any loss, we could power a computer to count up to 2192. Of course, it wouldn't have the energy left over to perform any useful calculations with this counter.
    
    But that's just one star, and a measly one at that. A typical supernova releases something like 1051 ergs. (About a hundred times as much energy would be released in the form of neutrinos, but let them go for now.) If all of this energy could be channeled into a single orgy of computation, a 219-bit counter could be cycled through all of its states.
    
    These numbers have nothing to do with the technology of the devices; they are the maximums that thermodynamics will allow. And they strongly imply that brute-force attacks against 256-bit keys will be infeasible until computers are built from something other than matter and occupy something other than space.*
    

    I’m not a physicist but quantum particles were still considered to be matter the last time I checked.






  • Can you get into your router’s admin interface? At the very least assuming you don’t have much networking experience I’d do these things in this order:

    1 - Check for firmware updates and apply them

    2 - Factory reset

    3 - Change password

    4 - Recheck for updates in case the reset wiped them out

    There’s a million other things you can do to get more info on what’s going on and put in security layers to do this and that. But if you just want the maximum results for the minimum effort this is the best place to start.


  • Sorry, I've been trying to login at least a couple times a week but haven't seen any notifications that there were new posts. I tried to watch the video but it says the r/DIY community is private. Just based on your description though I was wondering if maybe you need to balance the fan blade. I've had that problem with a few cheap fans and was able to get them to run about 90% more quietly by just eyeballing the blades and bending the one that looked "off" back into place. I think Mattias Wandel has a video somewhere on how to get really scientific about it if you want to get down to zero vibration.



  • Sounds like you’re looking for boots, not shoes. I hear you, I hate how I can rarely find a good pair of shoes and then when I finally do, they wear out in 1-2 years and anything remotely similar to them has been discontinued. I hate walking through a snowbank in winter and having it get wedged around my ankles. I hate stepping in a puddle and it turns out it’s deeper than expected and your feet get soaked. Fuck shoes.

    Several years ago I got a pair of Redwing 4473 boots with the zipper insert (I’m too lazy to mess with all those laces) and they’re still my primary work boots. I just had them resoled for the 2nd time and they’re in excellent shape again. Awhile back I realized that they were by far the most durable, comfortable, and all around best pieces of footwear I’ve ever worn in my life despite a complete absence of cushioning, gel insoles, foam padding, etc. So I ditched shoes altogether and just wear work boots that can be resoled. I just don’t wear the nicer pair when I’m painting, digging, mowing, etc.

    They don’t make the 4473 anymore and I heard the overall quality has gone downhill but I think you still need to research the individual boot model as much as the maker because some are winners and others are lemons. For my nice not-work boots I’m trying out the Solovair crazy horse gaucho 11 eye derby boot. A local cobbler installed a side zip on them for me for $70 because again, I’m lazy and don’t like to screw with boot laces. I won’t know whether they’re worth it or not for a few more years but I like how they look and they’ve been comfy enough so far. Pair some good leather goodyear welted boots that are properly broken in with a pair of wool Darn Tough socks and you’ll never go back.


  • I added a sink to it over the weekend, now there's a place to rinse out paintbrushes and wash hands. It's hooked up to a garden hose, so there's no hot water. There's a twist timer at the end of the hose so it will shut the water off automatically after 2 hours in case the 3 year old leaves the sink running. The drain just goes out the back corner and into the lawn. I've been dumping my buckets of paint water in the side yard for several years now and it hasn't killed my grass yet so it should be OK.

    It works perfectly! I was able to leave a 6 and 3 year old out there with 50 little paint bottles completely unattended for 45 minutes while I made dinner last night. There's paint all over the place in the playhouse but none got in their hair or in our house so I call that a win.