The website itself is a demo, as it says in the article. Here's the documentation for more details: https://aether-cms.pages.dev/

I feel the issue is deeper than that. We no longer buy products, we rent them, it's hard for consumer protection laws to catch up with that (even European).

How so? The rental vs buy setup is orthogonal to respecting people's privacy.

Censoring of token/s values in the sample output surely means this runs great!

Frequencies you don't hear - can't hurt you, or rather they cannot damage your hearing. Sure, submerging your head into an ultrasonic cleaning bath will irritate your skin, but the energy won't vibrate away your hearing abilities, if it had the potential to do that you'd hear it as a loud unpleasant sound.

Haha my dyslexic ass read the title as “MiniKaren”… I was half-expecting to see some miniaturized version of someone complaining at a grocery store or something

Thank you. I was about to just write "confirmation bias" as a comment.

Just using "cropped" as a negative prompt eliminates this issue entirely on my end and produces same results as per their owl example in SDXL.

ROS doesn't need a clone, it needs a successor.

Took the bait as well.

ROS2? I'll see myself out...

Could someone explain the joke? I've been dabbling with learning robotics and I've been confused by how ROS and ROS2 both appear to be actively developed/used. Is ROS2 a slow-moving successor version (like Python 3 was) or a complete fork?

Slow-moving successor, which the community isn't exactly going wild over. It offers modest improvements in exchange for a painful upgrade process, and many of the original issues with ROS1 remaining unsolved.

The other half of the joke is that ROS was never an operating system either.

Well there is one thing that ROS 2 does better, you can declare params directly inside nodes and reconfigure them all without building extra config files. And it doesn't stop working if your local IP changes.

But the rest are firmly downgrades all around. It's slower (rclpy is catastrophically bad), more demanding (CPU usage is through the roof to do DDS packet conversions), less reliable (the RMWs are a mess), less compatible (armhf is kill). The QoS might count as an improvement for edge cases where you need UDP for point clouds, but what it mostly does on a day to day basis is create a shit ton of failure cases where there's QoS incompatibility between topics and things just refuse to connect. It's lot more hassle for no real gain.

Config generally feels more complex though, since there isn't a central parameter server anymore. The colcon build system also just feels more complex now, which I thought was already impressively complex with catkin.

Yep it takes super long to get parameters from all nodes cause you need to query each one instead of the DDS caching it or something.

And yeah I forgot, there's the added annoying bit where you can't build custom messages/services with python packages, only ament_cmake can do it so you often need metapackages for no practical reason. And the whole deal with the default build mode being "copy all" so you need to rebuild every single time if you don't symlink, and even that often doesn't work. The defaults are all around impressively terrible, adding extra pitfalls in places where there were none in ROS 1.

It does a lot of things better but it also does a lot of things worse and also doesn't fix a lot of the real problems with ROS as a system.

ROS2 has been pushed a the successor to ROS for like a decade, and people still prefer ROS for various reasons. So yeah like Python 2/3 kinda.

No it’s much worse, python3 was all round better, it just took a while to get all your dependencies ported which made the transition hard. Judging by the comments it doesn’t seem like people agree that ROS2 is even all round better from ROS.

It's funny this topic came up today because I have a group of students working on a ROS2 project and at our meeting this afternoon they had a laundry list of problems they've been having related to ROS2. I'm thinking our best option is to use ROS1...

You're right ROS2 isn't all round better than ROS so the transition will never happen fully.

FWIW I'm working on an actual replacement for ROS, I'll post it to ShowHN one day soonish :P

Entanglement isn't particularly useful for communication, you can't send bits without sending photons (or similar) physically. Quantum mechanics doesn't permit ansibles as far as anyone knows.

While the second and third parts if your comment are complete true, the first part

> Entanglement isn't particularly useful for communication

I would say is false. Entanglement lets you do some fun and theoretically useful stuff for communication tasks. At the most basic level sharing entanglement lets you upgrade a classical communication channels you have into a quantum one (sending 2 bits and burning an entangled pair lets you send a qubit). You can do increasing fancy stuff if you so wish, if you are sufficiently paranoid you might be interested in device independent cryptography, which is only possible because of entanglement.

Yes, they are fun, but not notably useful, at least not yet. And only useful for pretty specialized tasks like key exchange.

Isn't it true that in key exchange entanglement isn't used in any way shape or form for sending data, but only in making a determination that there was no eavesdropping on the transmission, because any eavesdropper would collapse the wave function.

So like you said, entanglement can't be used to send information, but it can be used to detect if the transmission was secure (I think)

There are many protocols for quantum key distribution/exchange so it's hard to answer fully without knowing which one you're talking about. That said their are protocols, like the one invented by Artur Ekert in 1991, which use entanglement in an essential way to transmit the key. Even in the absence of an evesdropper the protocol will not work without entanglement. It escapes the no-communication theorem by also requiring some classical communication.

Right, if you expand the scope of the discussion to other areas other than sending bits, there are various ways entanglement is used in various protocols. But none of them utilize entanglement to be able to get a bit from Alice to Bob faster than light can go.

I had to google ansible. https://en.wikipedia.org/wiki/Ansible

Is it the issue or is it rather than any measurement of entangled quantum state change is modifying the measurement to the extent that there is a chicken and egg problem?

Basically reading quantum data is also a write operation?

The issue the person above is alluding to is known as the no communication theorem.

It has a wiki page

https://en.m.wikipedia.org/wiki/No-communication_theorem

But the upshot is basically that entanglement doesn't let you do anything unless you send some classical data as well.

Thanks. The reason still seem to be related to the uncertainty principle although I am not sure.

The same way they explain no-cloning but it seems to be analogous to identity within a system with interaction from neighboring data. Ultimately there is no pure independent state. Data always exists within context. Hence causality and spatial preservation (no instant physical teleportation as far as is currently understood). (in very layman's terms)

I am unable to grasp why FTL communication would break causality, it's like my brain just refuses to accept it. Seriously, I've had it explained several times over the years.

Its probably mostly because you have an intuitive idea that there is some concept of "now" which is independent of the observer.

In special relativity this global "now" isn't a thing. It doesn't exist. There is no global now. Different observers who are in different places and/or moving at different speeds will describe different events as simultaneous.

In particular say we have an observer who sees an event A happening at time 0, and a second event (call it B) at time t and the distance between them is greater than c t. Then you can find observers who see A happening first, B happening first or the two happening at the same time. However all observers will agree that the distance between the events was greater than c times the time between them.

This seems like it would cause problems with causality, but it doesn't because we need the distance to be greater than c times the time, which means no lightspeed signal could get from A to B. If you allow ftl communication then this "escape" doesn't work anymore, and causality can be explicitly broken.

When you communicate, you're sending energy - whether it's sound waves or radio waves or whatever. Energy can't travel faster than c through spacetime. Now if you manipulate spacetime, such as a wormhole or whatever, then the end result can effectively appear as if it's FTL but its still going at c, its just traveling through less/compressed space.

    There was a young lady named Bright,
    Whose speed was much faster than light.
    She went out one day
    In a relative way
    And returned on the previous night.

Time flows differently depending on velocity with respect to your frame of reference. Two observers moving at different speeds with respect to each other see different time flows. At normal speeds this is negligible but at close to light speed... hoo boy. You get things like observers seeing events occur separately that occured simultaneously for their counterparts and so forth. So if you were able to send information faster than light somehow, you would be sending it from one frame of reference with one notion of time into another frame of reference with a different notion of time -- one which observes receipt of the message before it can observe the sender sending it!

It's all a big ball of wibbly-wobbly, timey-wimey stuff.

One intuitive explanation is that anything moving at the speed of light is experiencing no time at all (from the point of view of an observer) and if something is moving faster than light that means it's going backwards in time. (only massless virtual particles can)

If a clock stops or runs backwards that totally messes up "causality" which is about events interacting relative to a time order, and so time must exist for causality to make sense.

If you have two very very long trains several light years long, passing each other in opposite directions, and each train has FTL-comm devices, and the front and back end of each train can flash signal lamps that are synchronized with each other, your train will see the other train's rear lamp flash long before the other train's front lamp. The other train's front FTL-comm is sending messages 'back in time' to reach the other train's rear FTL-comm. By sending signals from your front, to your rear, to their front, to their rear, and back to your front, the message arrives before you sent it. So we think FTL-comm can not work.

If you did manage FTL communication, it seems like it might let you detect the notional absolute rest frame, so you'd be breaking special relativity anyway.

Yeah that's the point of the article really. The rest of special relativity remains intact though for subluminal particles, you still have Lorentz transforms and energy-mass equivalence and all that stuff.

That post is very straightforward, thank you!

You can't grasp this because there is no FTL communication. Quantum entanglement does not enable FTL communication, and wormholes etc. are entirely theoretical.

It doesn't even enable STL communication, other than eg superdense coding and similar. But that's not what people mean when they think entanglement can be used for communication.