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Comment Re:Benefits cliffs penalize work (Score 1) 412

There's still a cliff. There has to be a cliff, although in the opposite direction of what you currently see. There has to be a significant jump in wages by getting off your ass and working in order to motivate people to do so. It penalizes companies, as those low end jobs now have to be paid significantly above what used to be minimum wage, counting both direct wages and wages paid in through new corporate taxes.

Comment Re:Same marketing BS as "hyperthreading cores" (Score 1) 311

The alternative is to try to call them "dual module" processors, and then go through a big long explanation to customers who really don't care what "module" actually is.

Can it execute two separate threads simultaneously? Yes. At full performance? Mostly, although with a shared frontend, when both units are running at full load, instruction disp---- Is someone trying to make a practical judgement of a chip's performance based solely on its core count going to have a clue what any of that means? No. Then it's a four-core processor.

Comment Re:Only if you use App Cards with APPS! (Score 1) 317

The US went chip & signature instead of chip & PIN, so the entire change is basically meaningless.

How so? With chip and PIN, if your card is stolen, the attacker either has to accurately guess the PIN before the chip self destructs (unlikely, but not impossible), or disassemble the chip to extract the data. It buys you a small amount of time to contact your card issuer, and have your card key deactivated. With just chip, your card is stolen, and can be used immediately, so you potentially have a couple additional transactions that you would not have had were it protected with a PIN.

In either case, the card must be stolen. That's the real purpose. A stolen card with a PIN is only going to buy you a few extra hours. The real protection is that the private key stored on the card cannot be non-destructively accessed. It cannot be skimmed without the owner's knowledge. It cannot be stored by a retailer and compromised. The owner is expected to notice the loss of the card and report it to their issuer, deactivating the key.

Comment Re:Wifi saturation? (Score 1) 152

Ultimately, it's still a violation of the NEC. You can run low voltage signaling through high voltage conduits, provided proper wiring, but standard CAT6 and its endpoints is not rated for that. Is it going to cause any practical problems in residential wiring? Assuming you're using shielded and properly grounded CAT6, probably not, but you may run into trouble if you have to file an insurance claim or try to sell the property.

Comment Re:a bright future (Score 1) 40

Not "commercial flights as we know them", just "commercial flights, period". Commercial aviation only exists because it exists as it does. You mandate solar power, and now you've mandated aircraft that are no faster than wheeled vehicles. Transportation would shift back to those vastly cheaper wheeled vehicles, and commercial aviation would all but go away.

Comment Re:Took a few seconds (Score 1) 217

This isn't a particle accelerator. You're accelerating your launch vehicle with the very same magnets which are levitating it around that curved track. If they can bend it around a 1km radius, they can accelerate it linearly in a shorter distance than that.

There's also the minor issue with all launch rails, linear or circular, that your orbital inclination is basically fixed by the installation. You're not going to have the energy to perform any significant plane change at 8km/s, especially with a kick motor that's supposed to survive a 2000g launch.

Comment Re: Solar-Thermal (Score 1) 282

Concentrated solar thermal gets much better performance than nuclear thermal because you're only limited by the materials properties of your heat exchanger, not your reactor fuel. The problem with solar thermal is three fold.

First, you have to be able to see the sun, so your burns are restricted to times where you're not in Earth's shadow. That could make transfer windows difficult to hit, of course if you have a thousand seconds or higher ISP, that's not such an issue.

Second, we're talking about high thrust rockets so you don't have astronauts sitting in the radiation belts for days as a low thrust rocket spirals out. That means you're going to have to have significant structure to support that concentrator, and it's no longer going to be very lightweight. Of course with such a high ISP, this may no longer be such an issue.

Third, this reflector cannot simply be static. It needs to be able to articulate to whatever angle you need to thrust, which greatly increases the complexity and mass of such a system.

Comment Re: Ion Thruster (Score 1) 282

But if you want to move great masses you'll need something more powerful.

No one here has actually made an argument about why they can't be scaled up, but just waved their hands and said "Nope."

No one has ever said they can't be scaled up. The problem is one of electrical power. ISP is directly proportional to exhaust velocity. While high ISP means high propellant efficiency, it also means low power efficiency. 200kW fed into a moderately high ISP NTR is going to offer much more thrust than a very high ISP ion drive. On top of that, the NTR uses the thermal output of the reactor directly, while the ion drive is going to suffer huge losses first converting that to electrical.

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