Along similar lines, the double-slit experiment, seems simple. Two slits let light though and you get bands where they constructively or destructively interfere, just like waves.
However I still find it crazy that when you slow down the laser and one photon at a time goes through either slit you still get the bands. Which begs the question, what exactly is it constructively or destructively interfering with?
Still seems like there's much to be learned about the quantum world, gravity, and things like dark energy vs MOND.
I had a conversation about this in HN some months back. It's a surprisingly modern experiment. It demanded an ability to reliably emit single photons. Young's theory may be 1800 but single photon emission is 1970-80.
(This is what I was told, exploring my belief it's always been fringes in streams of photons not emerging over repeated applications of single photons and I was wrong)
To get single photons, you just need to stack up enough stained glass infront of a light source. That's been acheivable for aeons (the photon will go through at random time though).
The difficult part is single photon _detectors_, they're the key technology to explore the single-photon version of Young's experiment (which originally showed that light has wave-like properties).
The most simple answer here is the "fields are real, particles are excitation patterns of fields." And that's generally the practical way most physicists think of it today as I understand it.
If I make the equivalent of a double slit experiment in a swimming pool, then generate a vortex that propagates towards my plywood slits or whatever, it's not really surprising that the extended volume of the vortex interacts with both slots even though it looks like a singular "particle."
> However I still find it crazy that when you slow down the laser and one photon at a time goes through either slit you still get the bands.
why does nobody mention the fact the photon doesnt keep going through the same hole? like why is it randomly moving through the air in this brownian way? the laser gun doesnt move, the slit doesnt move, so why do different photons end up going through different holes?
Sure, if you are smart enough. Maybe mount a small transmitter on a tree then use a directional antenna at a very low power and use the tree as a repeater.
Or use NVIS, which at least makes triangulation harder.
Not that I have to tell this crowd. Tuxpaint is free, get it from tuxpaint.org, do not buy it, do not download it as part of a "desktop". I was talking to the author, apparently it's sadly often used to trick people into buying or downloading malware.
I set up my kid, I think she was 3 or so, she started out with stamps of butterflies and the like. After awhile she looked at her hand, then mouse, then me, stared at me and said "ouch". I got a "travel" mouse that was half size or so, perfect for her hand and she loved using tux paint.
Don't forget to setup sound, preferably in stereo.
She used the hell out of it for years. One time on a call she was fascinated by fish. I printed out one of her drawings remotely while we were on the phone and she loved it.
Keep in mind the desktop env knows when you are left clicking a link or middle clicking. So on linux, usually it's left click to go to a link or middle click to open link in a new tab.
Middle click to open new tabs is compatible with middle click to paste.
In reality such features are often dropped, no settings in gnome-settings, and non default features are not tested in new builds.
So you end up googling how to get that feature back and the answer is manually navigating the config tree or using gnome-tweaks, both with large disclaimers that any changes might break your system.
No thanks, I'd rather have left click to select and middle click to paste, do we really have to involve the keyboard by default?
Similarly gnome-terminal used to have "new terminal" as the first option in the menu of a terminal. Then it got moved down to 6th item, then in the newer versions removed completely.
Sure. But it's a depreciation and there's numerous similar settings that are only available by tweaking settings manually or using gnome-tweaks. Right now nearly every linux app supports select with the left button and paste with the middle. It's fast, useful, doesn't require a keyboard, etc. Amusingly I've seen various logins block control-v, but middle click works. God forbid you use a password safe with your bank login.
When you use gnome-tweaks there's a ton of "WARNING you may break things" and of course anything off the default path is likely to receive zero testing.
Personally I find middle click to paste one of the differentiators between MacOS, Windows, and Linux. I'm pretty surprised it's not more common. I was amused the iterm2 added select without having to type control-c.
I don't have a static IPv4 address and I have to use a DDNS built into the Caddy plugin on my OPNSense router. From what I understand, you can't get a static "local" (I know, IPv6 has no direct equivalent) address to use for a reverse proxy — at least not in an easy manner. I might be completely wrong but that's why I don't bother with IPv6.
Yep. ULA addresses are the equivalent of 10.0.0.0/8, 192.168.0.0/24, and 172.16.0.0/12 space. [0] And you can use them to do NAT, just like with IPv4.
The huge difference from the IPv4 world is that the procedure for generating your /48 ULA prefix ensures that it's very, very unlikely that you will get the same prefix as anyone else. So, if everyone follows the procedure, pretty much noone has to worry about colliding with anyone else's network.
Following the procedure has benefits. For example, VPN providers who want to use IPv6 NAT can do that without interfering with the LAN addressing of the host they're deployed to... companies that merge their networking infrastructure together can spend far less (or even zero) time on internal network renumbering... [1] etc, etc, etc.
[0] And link-local addresses are the equivalent of 169.254.0.0/16 space.
[1] Seriously, like a year after one BigCo merger I was subject to, IT had still not fully merged together the two company's networks, and was still in the process of relocating or decommissioning internal systems in order to deal with IPv4 address space constraints. Had they both used ULA everywhere it was possible to do so, they could have immediately gotten into the infosec compliance and cost-cutting part of the network merging, rather than still being mired in the technical and political headaches forced upon them by grossly insufficient address space.
> Problem with ULA is that it's functionally useless on a dual-stack network.
Nope, it works just fine. I use it for stable local addressing and LAN host AAAA records and let my ISP-delegated global prefix drift as my ISP wishes it to.
And -as it happens- the prose in that article about source address selection is incorrect.
On Linux, source address preference appears to be application-specific. For example, curl prefers IPv6 addresses, and falls back to IPv4 if the v6 connection fails. I checked just now by removing my globally-assigned IPv6 address, and capturing the traffic created by executing 'curl https://www.google.com'. I know for a fact that BIND 9 prefers non-link-local IPv6 source addresses over IPv4 addresses because until I set up my home-built router to reject Internet-bound traffic coming from my ULA, a sufficiently-long failure of the DHCPv6 server run by my ISP would cause name resolution to get very, very, very slow when the global prefix expired and BIND started using its host's ULA as a source address and my router dutifully relayed that traffic into my ISP's black hole. I'm certain that very many applications unconditionally prefer non-link-local IPv6 addresses over IPv4 ones. You might also care to pay attention to this comment and its publication date: [0]
OTOH, Firefox prefers IPv4 connections in that scenario and doesn't even attempt a v6 connection. I assume Chrome is the same way.
And, that article suggests GUA space as a replacement for ULA space:
> All of these are serious pitfalls that arise when attempting to use ULA. The simple and more elegant answer is to simply leverage GUAs.
Which... uh... no. I'd have to go through my local RIR to get an allocation, and then negotiate with my ISP to get it routed. Given that I'd have to go through ARIN because I'm in the US, and I have a boring residential account with my ISP, neither of those things will ever happen. The entire point of ULA is that no coordination with external entities is required to do network-local addressing.
Also, the documentation that that article links to to discourage people from deploying NAT66 is almost literally "It's exactly as complicated as NAT44. Why do it when you can get global IPv6 addresses?!?", which isn't a useful complaint when your intent is to exactly replicate what you get from IPv4 NAT in an IPv6 world. I agree that globally-routable addresses are better, but if your site admin demands (for whatever reason) that you not have them, then -because of the collision-avoidance property of the ULA prefix generation procedure- you're better off than with IPv4 NAT.
Note that although the policy is that you choose a random prefix, nothing actually enforces this and nothing stops you using fd00::1, fd00::2, etc just like 10.0.0.1 etc.
No, but they can skip the socket, much like many of the mini-pcs/SFFs that include laptop chips in small desktops. Strix halo already doubled the memory channels and the next gen is supposedly going to move the memory bus from 256 bits wide to 384 bits.
However I still find it crazy that when you slow down the laser and one photon at a time goes through either slit you still get the bands. Which begs the question, what exactly is it constructively or destructively interfering with?
Still seems like there's much to be learned about the quantum world, gravity, and things like dark energy vs MOND.