And by "more difficult", you mean that there is a massively larger amount of efficiency loss. If you're lucky, you recapture 60% of the energy in the fuel, and multiply that times the 75% efficiency for electrolysis, if you're lucky, and you're throwing away more than half the energy that goes in. So if folks are freaking out about the power grid not being able to handle EVs, imagine what would happen if you doubled the power requirements.

It's not really that bad. You can put probably ~500 miles of range into a hydrogen fuel-cell vehicle in 7 minutes versus 200 miles in 15 minutes on a modern EV. It's actually pretty comparable to a gasoline-powered vehicle. But you do still have to stop, unlike with an EV, where 90% of your charging can be done plugged in at home while you sleep. So in that sense, it's slow.

I've said similar things about NASA's Artemis mission for the same reason. Doesn't everybody want to use a fuel that is almost impossible to keep from leaking, and then spend the better part of a year with the rocket stuck on the pad trying to fix the leaks so they can launch it? :-D

Is it really? If Steam said, "No, we'll find another processor that isn't trying to run our business for us," they would probably not get as low a fee, but that's far from existential. It's not like the actual payment networks give a crap. They get paid either way, even if the transaction gets refunded. It's the merchant account providers that are the issue, and if one is a problem, there are almost a thousand other companies who will gladly step in and fill the void.

So from my perspective, this is Steam saying, "We've decided that the cost impact from taking payments for this type of content is too high, so we're not going to sell it anymore," which while entirely within their rights to do, is a far cry from "The payment processors made us do this." There's always a choice.

Payment providers don't work with game developers anyway. Payment providers work with Steam. Steam can't pay developers in certain countries, and they therefore presumably aren't eligible to sell on the Steam store.

So no, this has nothing to do with who gets the money. No matter what, Steam gets the money, and Steam pays somebody else.

Just curious how much SteamOS contributes to that total.

Exactly. It is possible to perform verification in a near-zero-knowledge way, where the only thing that the government entity that issued your ID knows is that you used X browser to verify your identity. If the browser nags you to do this until you agree, that provides no information to the relevant agency about whether you actually used it. And as long as the agency has millions of IDs, knowing what agency verified the ID tells the site *almost* nothing about who the user is.

And the proof of age can be safely stored in the browser, so long as the actual identity is not, because the proof should not contain any actual identity information beyond what state/country issued the ID.

And this is why nothing other than a photo of a driver's license should ever leave the device. If you design the system to not provide any information about whether the user is actually accessing an adult site at the time, this becomes a fairly innocuous piece of information to leak.

Ah, but with that approach you have no privacy at all, because the government would have to interact with the adult site, and now they have the knowledge that you don't want them to have.

That also doesn't necessarily work, because even still, that entity has to do so, and if they have the information, it can be subpoenaed.

No, the *only* way to prevent leaks is to compartmentalize the information so that no single entity has both the knowledge of your identity and the site you are visiting at the same time. This can be achieved by the browser pushing you to verify your age continuously until you agree, and storing only the proof of age, not your actual identity, such that the identity is ephemeral, and never exists in the same place and time as the URL of the site you want to visit.

Worth noting also that it's doubly hard to do that in a way that doesn't provide evidence that the user went to an adult site, though, likely requiring some sort of randomly timed requests designed to have similar frequency distributions to actual adult site access.

That's an implementation detail. The one thing that is certain is that only the browser can do this in a way that doesn't provide the government or a quasi-government entity with information about what site you went to, because if you send credentials to a website, it will have to know what website to handshake with, and it will know who you are. And even if you do some interesting privacy-protecting handshake in JavaScript, it is too easy to modify to compromise privacy, and you'll never know it if one of a hundred verification sites does this. With a browser, there would be only a single-digit number of interesting implementations worldwide, so monitoring them is practical.

My first thought is that a best-effort approach is good enough. You provide your photo ID once, and if the website requires additional validation, the browser can also require you to take a picture with your webcam once for verification purposes.

After you verify your identity, you should have a choice between leaving the browser permanently authorized on a non-shared computer/device or requiring a passcode/Touch ID tap/Face ID scan on a per-use basis, at your option, for a multi-user device. Either way, that decision must be in the user's hands, rather than the browser's, the website owner's, or the government's hands, or else it becomes psychologically abusive, and a tactic for discouraging use of certain sites.

The browser then verifies the photo (on-device), if applicable, uses OCR to determine the issuing authority, and sends a random nonce to the issuing authority along with an image of the photo ID (not a photo of the user, because that could reveal where the user is, what the user is wearing, and other potentially privacy-violating details, depending, making that an unreasonable thing to do).

The authority signs the nonce provided by the browser and then sends back the signed nonce. The browser then verifies issuing authority's public key against a periodically updated shared database of issuing authority root certs, and sends back the fully validated request to the requesting website, which should also validate the signature against its shared database of issuer certs.

For this to be secure and privacy-protecting, you need a few guarantees:

• The photo used for verification, if required, never leaves the device (and this practice should be strongly discouraged).
• The retrieval of the issuing authority's public key must always be from a local root store, not by retrieving it directly from the authority at the time of access, to prevent information leaks through timing attacks.
• The issuing authority must use multiple overlapping signatures to ensure a reasonable transition period when signing keys/certificates change, so that sites can update their local root store on a weekly (or, ideally, monthly) basis.
• There must be a central authority providing either downloadable root stores or downloadable lists of URLs for per-country root stores (the details of this part of the implementation are not that important).
• No issuing authority may have fewer than a few million users.
• Browsers must encourage users to verify their age as soon as the feature is added (or afterwads, whenever the user first runs the browser), and periodically after that, so that age verification does not create any presumption that the user is actually going to what any particular country considers to be "adult" sites.

In an ideal world, you'd go one step further and have the website provide the nonce. Then you'd use some sort of zero-knowledge proof to prove that a certifying agency trusted by the browser knows the nonce without revealing which certifying agency it is, thus preventing it from revealing anything about the user, including the user's country/state, but I'm not entirely sure how you'd pull that off in a way that doesn't require trusting the browser to not be compromised with fake authorities, so that optional next step is left as an exercise for the reader.

No. It needs to be high enough that the submitter limits the number of submissions. I expect that $1 would suffice, but that's a guess.

OTOH, I'm reluctant to pay money over the internet, so I am usually only willing to do so if I have a previous financial-over-the-internet transaction history. So it might limit the valid bug reports/suggested fixes.

That's a weird way to think about things. A computer can definitely be an instrument, but instruments aren't the essence of music anyway.

The essence of music is how the listener reacts when hearing it. Period.

It's my understanding that hologram rock stars are very popular in Japan, though perhaps that was just a decade ago.

There's nothing intrinsically impossible about that scenario. I don't think we're quite there, yet, but only because that's not the way the effort has been directed.

OTOH, none of those steps justify copyright. And none of the even ADDRESS the quality of the product.

Mark parent insightful!

There are copyrights on the performance as well as on the work itself. It *will* change the performance copyright, because the only copy made available will be the more recent performance.

Book publishers do the same thing. Yeah, the old edition is out of copyright, but the new one had changes, and you can't find the old one. And the new one is under copyright.

Unless it's straight down from overhead (satellites, drones, etc.), in which case the curvature of the earth goes away as a factor, and you're just left with attenuation.

Wait, overpower another signal? That's a new detail.

First, I would assume that such a signaling mechanism would use some sort of spread spectrum or frequency hopping approach to allow multiple senders, or else you'd kind of have a signal-shaped mess on your hands, unless the wattage is *really* small, because presumably a train would "see" more than one signal/switch point at any given time. And if it is really small, that makes it easier to overcome.

Second, if this is PTC we're talking about here, I don't think there are PTC signals on every mile of track all across the country. They put that stuff where it is needed, e.g. near curves with slow speeds. Anywhere else, there would presumably be no signal to overcome, making the threshold for detection way lower.

From a quick Google search (which might not be accurate, given that I didn't dig into the results deeply), PTC receivers on a train can detect signals as small as -95 dBm. A SpaceX satellite can push 34.47 dBm (though whether it can do it at that frequency or not, I couldn't say). You'd have about 5.5 dB of atmospheric attenuation at that frequency and about 92 dB of free space path loss. So given line-of-sight from space through open air, I think getting the signal to be detected by a train should be feasible in the absence of an interfering signal from the ground, with a fairly sizable noise margin, but I could be understanding the math wrong.

That said, even if you had to overwhelm a multi-watt signal, such that a satellite was infeasible because of the signal loss, that would still leave drones, balloons, things left by the side of the track, things hanging from bridges, etc. After all, sending out a few watts from the ground is really no big deal. I've seen handheld CB radios with that much output (different frequency, but you get the point).

So I think you're overestimating how hard this would be to exploit. But I could be wrong. I'm not an RF engineer, and I don't really have the desire to spend a lot of time researching this. Again, my gut says if nobody has exploited this to cause chaos, it means nobody cares enough to bother, which is probably good, because it means there are way fewer terrorists, etc. than we've been led to believe.

Can PTC not completely stop a train? I thought it could. If so, then there's no reason you couldn't completely stop the train. It isn't hard to transmit a signal for a couple of miles in that frequency band. A watt or two should be adequate, plus whatever you need to overcome any other signals if there are any at that particular spot.

This feels like it would be a great Bond movie plot. Someone stops a train and robs it using a drone with a fake PTC signal.