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Comment The general issue is decentralization & resile (Score 1) 549

Exactly. Building any kind of colony in space will probably be easier and less expensive than building it on Mars. If nothing else, it will be a lot easier to send the initial manufacturing equipment there, since it will be a lot closer to Earth. And once it's built it will have lots of advantages: closer to Earth, no gravity well making it hard to come and go, closer to the sun (hence much greater supply of solar energy), and you get to live in normal Earth gravity (from rotating the colony to create artificial gravity) rather than the 38% Earth gravity you get on Mars. We don't even know if humans *can* be healthy living long term in such low gravity.

Way back in 1975, NASA estimated the total cost of building a space colony large enough to permanently house 10,000 people at $190 billion. And that was relying entirely on 1975 technology. This is totally something we could do, if we really wanted to.

Comment Re:Public cynicism about fusion (Score 1) 147

There's enough deuterium to last 100,000 years, but we'll go through it all in 1000 years anyway. Never underestimate the ability of humans to be wasteful when they don't have an incentive to be efficient.

Fortunately, solar doesn't have that problem. It gets delivered to us at a nice steady rate, and that isn't going to change much for many millions of years.

Comment Re:Public cynicism about fusion (Score 1) 147

It took somewhere between 1500 and 1700 years from the time the first steam engine (aeolipile) showed up until it was practically applied.

That's not what I mean. That was the time between when someone came up with a cute toy and when someone starting trying to do something useful with it. I'm talking about how long we've had an active fusion energy program spending large amounts of money every year to try to create something practical. When they started out, they thought they could have something in ten years. Ten years after that, they thought they could have something working in ten years. Ten years after that, they STILL thought it was about ten years away. Sixty some years and billions of dollars later, even the optimists are saying it's 20 years away.

Besides, you demonstrated my point exactly. Centuries before anyone tried to develop a steam engine into a useful device, they already had a working proof of concept.

One other thing to keep in mind is that fusion, if we can find a way to make it work, could potentially outshine every other technological achievement in human history up to this point because of the possible applications.

Why do you think that? What's so amazing about fusion that makes it so much better than every other technological achievement in history? Sure, it would solve all our energy problems for about a thousand years, at which point we would have burned through most of the available fuel because, having no incentive for efficiency, we would have wasted most of it. (Yes, I'm cynical about humanity.) But solar energy is equally capable of solving all our energy problems. And unlike fusion, it's a real technology that actually works today.

Comment Re:Public cynicism about fusion (Score 2) 147

Isn't that true of pretty much every technology that's still in the development stage?

No, I don't think it is. Pretty much every technology that has gone on to be successful has started from a simple, working proof of concept and then scaled up from there. That covers everything from the steam engine to the telephone to nuclear energy to the microprocessor. Contrast that with fusion energy: 60-odd years of work, many billions of dollars spent, and we still don't have a minimal working proof of concept.* That's pretty depressing. Can you name any other technology that started out as badly yet went on to become successful? I can't think of one.

Given the history, I think extreme skepticism is the only rational response.

* By a "minimal working proof of concept", I mean a controlled fusion reactor (not a bomb) that produces more energy than it takes to run the reactor (and hence actually functions as a power source).

Comment Bad summary but cool project (Score 1) 133

Don't be put off by the clueless submitter. This is actually a really cool project that goes way beyond existing types of automation. This quote, for example, gives a sense of the kinds of things they're trying to enable:

The tremendous potential that FarmBot creates, allows for many new methods of farming, including the ability to create “polycrops” which mix and match different crops, unlike methods seen on typical farms.... Traditionally this has been impossible, as each different plant species requires different care techniques. For example, some crops require more water than others, while some crops require water at their stalk, rather than at their base. Some plants require more or different types of fertilizers than others. FarmBot’s software makes this process extremely simple, as each plant can virtually be programmed for their individual needs.

Comment Re:Uh? (Score 1) 147

On a similar note, I don't know that T-Mobile's music streaming policy is terribly unfair, since they're whitelisting all the major streaming music providers. If they made Pandora free while Slacker had to pay, that's not 'net neutral'. Since everyone who streams audio is included, it's a blurry area for net neutrality.

Here's one they don't include: totallyweirdsounds.com (all Tuvan throat singing, all the time!) Never heard of it? Of course not, I just made it up. But suppose I wanted to start that site. Millions of T-Mobile users would say, "If I use your service, it'll eat through my data cap, but if I get my Tuvan throat singing from Spotify it doesn't." I'd be at a huge disadvantage.

Net neutrality is about providing a level playing field. Not just for established companies, but for everyone. Maybe T-Mobile is doing this with good intentions, but they're creating a barrier to any new music streaming service that comes along. Besides, if they want to raise their customers' data caps (which is effectively what they're doing), why not let customers use that data however they want?

And it's not like they even have all the major services. Google Play Music? Nope. TuneIn? Nope. SoundCloud? Nope. Those, perhaps by coincidence, are precisely the services I stream music from most often.

Comment Just because you can do something (Score 1) 44

Congratulations, you're being a troll. They managed to take their existing app written for a completely different platform, and port it to the web in a way that runs flawlessly on my four year old laptop. Without having to rewrite the whole thing by hand in Javascript. I'd call that a big win, and a really cool achievement.

Comment Re:Computer Science (Score 1) 637

Exactly! Computer Science != Software Engineering. Yes, a software engineer needs a solid knowledge of computer science, just as an electrical engineer needs a solid knowledge of physics. But a degree in CS doesn't prepare you to be a software engineer any more than a degree in physics prepares you to be an electrical engineer.

In my experience, people who get to college and decide, "Computer science seems like a good career, so I guess I'll major in that," tend to become bad programmers. People who major in CS because they love computers and have been programming for fun since they were 12 tend to become good programmers. They're motivated to learn on their own all the things their CS classes don't cover, and likely have already learned a lot of them before they even get to college.

There are some schools that actually offer degrees in Software Engineering. But I don't think I've ever known someone with one of those degrees, so I don't know whether they do a better job of training good programmers.

Comment Re:Welcome to the Privacy Free Zone (Score 2) 79

Everyone I've known from Singapore has been very clear about this: they did not "consciously choose" to surrender civil liberties. They were never given any choice in the matter. They were very unhappy about the lack of civil liberties there and wanted it to change.

Perhaps the people I've known were not representative of Singapore in general. But even so, it's manifestly absurd to claim they consciously chose something they have never been given any choice about and have no power to change.

Comment Re:Carry the one (Score 1) 201

2. No one is claiming this device is a "free energy machine".

Skeptics are, because all reactionless drives are free energy machines.

That's doublespeak. No one who believes in it claims it's a free energy machine. Ok, you are free to announce, "It's a free energy machine, therefore it can't exist!". But since you don't have any evidence to support your claim, that's meaningless. Either it works or it doesn't. If it does work, it almost certainly is not a free energy machine. No one has presented any evidence to indicate it doesn't conserve energy. If you make that claim anyway, it just shows you're making claims that aren't based on evidence. It tells us nothing about whether this device actually works or not.

It can be hard to get your head around, you may want to actually do the maths to convince yourself.

The only thing that's hard to get your head around is that you just made two assumptions that directly contradict each other. Conservation of momentum follows from Newton's laws of motion. If you assume momentum is not conserved, you aren't allowed to use Newton's laws anymore. But that's what you just did. You first assumed the existence of a phenomenon that violates Newton's laws, and then immediately started applying Newton's laws as if they were valid. If you make two assumptions that contradict each other, all your conclusions are invalid.

3. No one is claiming this device is "reactionless".

Skeptics are.

Same as above. Or to summarize:

Scientists: "Experiments indicate this device seems to work. We're not absolutely convinced yet, and we don't completely understand the mechanism. But if it really does work, we're pretty darn sure it must conserve energy and momentum."

You: "This device doesn't conserve energy or momentum. (Because, well, I just know it doesn't, even though I don't have any evidence to prove it.) Therefore it can't work."

Space doesn't work that way.

Say the device interacts with virtual particles, a la Casimir Effect. The physics of virtual particles is not analogous to regular particles. The net velocity of virtual particles is zero, regardless of the velocity of the EmDrive.

Now you're just making things up. There is no difference between "virtual" particles and "real" particles. They obey exactly the same physics. If a particle/antiparticle pair is created out of the vacuum and then is annihilated without ever being observed, we call them "virtual" particles. But while they exist, they can interact with other particles, and they interact in precisely the same way other particles do. Furthermore, that interaction can sometimes prevent them from annihilating each other, in which case we say they have become "real" particles that were created out of the vacuum by the energy of the interaction.

Actually, the whole concept of "virtual particles" is just an artifact of the mathematics: we don't know how to describe the true vacuum state, so we use perturbation theory to write an infinite series describing how it differs from another state we do know how to describe. And we call the terms in that infinite series "particles".

All of which is really completely irrelevant to the question at hand. A particle/antiparticle pair initially has zero momentum, but they absolutely can interact with other particles, and that interaction can impart momentum to them.

Comment Re:Carry the one (Score 1) 201

Wow, that was wrong in so many ways.

1. There is no such thing as a "free energy machine".

2. No one is claiming this device is a "free energy machine". You have to put energy in as electricity, and you don't get more energy out than you put in.

3. No one is claiming this device is "reactionless". There's ongoing discussion about the exact mechanism (assuming it actually works). They suggest it may be pushing against space itself, somewhat analogously to how a swimmer pushes against the water they're swimming through. But if it actually does work, it almost certainly conserves momentum.

4. In any case, conservation of momentum and conservation of energy are independent conservation laws that come from different symmetries of the universe. If one turned out to be wrong, that wouldn't automatically mean the other was wrong too.

Comment Thanks for the pointless scaremongering (Score 1) 409

The only novel thing is that they're bringing a highly contagious patient on an airplane half way around the world. If you think that's no more risky than bringing an inert, freeze dried sample in a tightly sealed container, well, trust me, it is.

Of course, I'm sure nothing could possibly go wrong. Unless the plane crashes. Or experiences mechanical problems and has to make an unplanned landing. Or any of lots of other things that could go wrong, does.

Comment Carry the one (Score 1) 201

Unfortunately, even though you wouldn't have to supply propellant, you would still need to supply the energy to accelerate it. After accelerating for one year, your potato's kinetic energy is 1.8e12 Joules. That's a lot of energy. Initially you can stick a solar panel on it to power the drive, but once you're out of the inner solar system that won't work any more.

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