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Comment No way to distinguish a legit survey from a scam (Score 2) 159

If someone calls or emails me wanting information, my first assumption is that its some sort of scam, or at least a marketing survey, and I don't have the time or interest in figuring out whether its legitimate. If I had a way to quickly know that it was a legitimate research survey, I'd be happy to answer.

Comment Most people don't want shorter work weeks (Score 1) 52

I expect that if if you give most people the option of a 4 day week for X$ or a 5 day week for X*1.25 dollars they will take the latter. In reality it will probably be > X*1.25 because all jobs have some "fixed costs" for things like training that mean that the work done in 5 days is > 1.25 the work done in 4 days.

Some will take the option, some will decide to work even less, but my guess is that the majority are willing to work more hours for more $

Comment Re:Such a cool mission, I don't care what it costs (Score 1) 30

Do you think high 6 figure salaries are unreasonable? In technical fields, the best people are far more productive than the average people so it makes economic sense to pay what it takes to employ them. In any case NASA salaries are far (2x-3x) below industry for similar skills.

I agree that there is a huge bureaucracy problem, but like all bureaucracies, its difficult to decide what parts to eliminate. My experience is DOE, but I expect its similar. Environment Safety and Health represented a huge expense - should we cut that? The purchasing system includes all sorts of checks and balances to prevent fraud - and I believe fraud is very rare - but at a huge cost. Project reviews are designed to eliminate risk because "failed" projects are a political disaster, but in order to make progress you NEED to take risks.

I wish NASA had stayed on the path it was on in the 60s but NASA's budget today is 10X less as a fraction of the federal budget than it was during Apollo and I don't see any hope that the public is willing to return to those levels of spending.

Comment Re:You should know better. (Score 4, Informative) 69

Its the standard rocket equation (as viewed in the frame of the rocket). https://en.wikipedia.org/wiki/...

In the non-relativistic case, if you need a delta-V that is larger than the fuel exhaust velocity, you need to carry an amount of fuel that grows exponentially with that ratio. (see above). In the relativistic case, its similar https://en.wikipedia.org/wiki/...
What is going on is that you need to accelerate not just the rocket , but the mass of the fuel that you will need for future acceleration. Start with the rocket mass. To apply thrust for acceleration * time = exhaust velocity, you need a factor of e in fuel mass. If you want to double your speed you need to do that again, so you need e*e mass ratio. And so on.

You can do the math, or write a simple program - just take small steps and work in the comoving frame of the rocket so that you can ignore relativistic effects.

Comment Re:Such a cool mission, I don't care what it costs (Score 3) 30

The NASA employees aren't getting rich. The director of NASA makes about as much as a moderately experienced researcher in an industry lab, and the rest of the pay scale is far below industry standards. There IS a huge bureaucracy but a lot of that is demanded by the public in order to ensure that there is no "waste", even though the bureaucracy itself IS the waste.

I worked for many years at a DOE lab and the fraud protections meant that everything required N levels of approval - often by people with no knowledge of what was being done. Now that I'm at an industry lab, I can pretty much buy whatever I need for research and presumably if I spend money inefficiently or on inappropriate things I'll get fired. Its far more efficient.

Comment Re:You should know better. (Score 1) 69

Sadly there is a rarely mentioned difficulty. Constant acceleration requires exponentially increasing amounts of fuel with time. Even with matter / antimatter as a fuel, its difficult to imagine getting a relativistic time contraction of more than a a factor of a few. (remember you need to decelerate at the far end which requires another exponential factor in fuel). Antimatter propulsion also has other difficulties, in both creation and storage. The creation of anti-protons is inefficient, there is a far higher probability of producing mesons that decay again. Its not clear how to store and accelerate high density anti-hydrogen, exceptionally low temperatures would be required to keep the anti-hydrogen vapor pressure low enough to prevent runaway heating. Maybe you could make an anti-hydrogen fusion reactor to get to carbon, but that reaction proceeds vastly more slowly than does DD fusion which we still haven't figured out.

"Bussard ramjets" seem impossible for a variety of reasons.

Its always risky to bet against advancing technology but this does seem really difficult

Comment Re:I don't understand (Score 1) 66

Most managers do not like firing people, both for personal reasons, because firings can be demoralizing to a team, and because the cost to train a new employee can be large. Its both the policy at most companies and generally good practice to find a way to fix problems, not just fire people.

Comment Re:Finally! (Score 1) 73

The most severe climate issues are long term. Fusion won't have any impact in the next couple of decades, but what we do over the next hundred years also matters. If fusion power can be made economically viable, it solves the majority of the world's climate problems. Its far from a sure thing, but seems worth a several billion $ investment, 1% of the investment in solar, and similar I think to what is spent on each new model of phone.

Comment Totally wrong! Domestic labor is the future (Score 1) 134

AI will likely become very good at investing because it can integrate huge amounts of data into a decision very quickly. AI is also becoming very good at a wide range of intellectual tasks and that will likely continue to expand.

So far though general purpose robots are nowhere near being as capable as humans and they are far more expensive. No single robot can make a bed, cook dinner, change a diaper, wash and fold clothes etc. The future is being manual workers. We should all train on doing domestic chores so that we can effectively serve our AI masters. I'm sure we will be well cared for, as high quality domestic servants have been for much of history.

Its possible that robots could eventually compete, but why bother when we already have self replicating, self repairing machines with a multi-decade working lifetime?

Comment Re:Good idea (Score 1) 72

Its wise not to document actual crimes you have committed, but what about hypothetical crimes? Maybe someone is writing a murder mystery. Maybe they just want to win an argument with a friend about how easy or hard it would be to assassinate the president. Maybe they fantasize about crimes they have no intention of ever committing.

I'd like to believe that the police can recognize the difference between fantasy crime and real crime, but I'm not convinced that is always the case.

Comment Re:Everything About AI is Harmful (Score 5, Insightful) 72

AI certainly has some positive benefit, I use it regularly at work both for coding suggestions as well as for physics an engineering questions. I don't trust the results to be true, but those results often include references that greatly reduce the time I spend investigating things. Does that "outweigh" the harm - I don't have a scale on which to measure that.

Almost every new technology has brought benefits and harms, and it can take a very long time to understand the balance. Did the internal combustion engine cause more benefit or harm? How about plastics, or even television. We've seen basically the full lifecycle of television now, and how would you compare the harm and benefits? More importantly your estimate of harm and benefits might be very different from someone else's estimate.

Comment Not qute what the headlne says (Score 1) 27

When they describe routing quantum signals over the same "infrastructure" as standard IP, they are just talking about the physical fibers, of course all the switching has to be new. Basically they are using classical IP data to control fiber switches that route the quantum signals. Then they run the classical and quantum signals on the same fibers.

So its OK, but not exactly surprising - once an optical switch with sufficiently low noise for quantum links exists, this is pretty straightforward. In the simplest version the qbits just run on a separate optical frequency, and are separated / combined with the classical data with wavelength division multiplexing hardware.

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