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Comment Re:Supernova Required (Score 1) 194

Actually it did not have to come from anywhere. Energy conservation relies on the laws of physics being constant in time. However since the Big Bang probably created those laws that would mean that it changed them and hence energy would not have to be conserved and so could be created. Alternatively it is possible that the Big Band created time itself in which case there was no such concept as energy before it (although "before" is hard to define in such a case).

Comment Re:The treaty says no such thing. (Score 0) 211

As unseemly as it might be to Canadians, an unrestrained land-grab in space is the most likely vehicle to spur progress.

It is also very likely to spur wars over territorial claims...hence the treaty preventing such claims. However extracting material from the asteroid and bringing it back to Earth seems like a perfectly allowed action under the treaty so long as the company does not try to claim that it is a US asteroid which they are mining.

Comment Opposite Effect (Score 5, Informative) 70

Actually if radiation is aligned with a crystal lattice it interacts even more with the material and the radiation length (the distance travelled before 1/e of the particles interact on average) gets shorter. However this only happens if the radiation is aligned to within a few milli-radians of the symmetry axis of the crystal (and most metal you encounter is not a single crystal). I actually measured this effect as part of my PhD thesis for an application in the main particle physics experiment I was working on.

So no, this material will probably be no more effective than the same mass of gold in a thin, but solid, sheet. Radiation shielding with matter is a statistical affair and the fewer nuclei you have the less shielding you get. I'm also surprised that they suggest a use in jewelry since they also describe it as easily malleable, far more so than solid gold. Still it is interesting.

Comment Supernova Required (Score 3, Interesting) 194

Even nuclear fission power comes from heavy elements fused at the center of the sun and spat out during an early nova outburst.

Actually a supernova is required to produce the heavy, fissionable elements. Based on the ratio of Uranium isotopes the one that gave us our heavy element occured about 6 billion years ago or about 1-1.5 billion years before the solar system and Earth formed.

The sun is powered by nuclear fusion which can only create elements up to iron-56 after which you have to put energy into the process to make larger nuclei. In stars ~4-5+ times larger than our sun this comes from the sudden gravitational collapse of the core when it has burnt all the way up to iron. The result is a supernova: the core collapses into a neutron star and the resultant release in gravitational potential power both the explosion as well as the production of the heavy elements beyond iron.

In fact if you really want to escape solar power the only option is nuclear fusion. However this could be regarded as a fossil fuel since you are using energy 'fossilized' by the Big Bang and is not renewable...but then there is no such thing as renewable energy if you take the really long term view.

Comment Look at Data (Score 1) 494

Since engineers and scientists naturally enjoy solving problems and sharing their knowledge, they fall into this trap easily.

Great theory but unfortunately there is a little problem that the data show that engineers are far more susceptible to this trap than scientists so your explanation completely fails to explain the data. Hence there must be a difference which you hugely long comment completely ignores.

Again I would argue that this is due to the big picture thinking of scientists. Give an engineer a problem of how to perform a "DoS attack on the enemy during a religious holiday" and that's what they will want to solve. Give the same problem to a scientist and they are more likely to ask what the goals of such an attack are and whether there are alternative and better i.e. more peaceful ways to achieve them. So the scientist may end up sympathizing but will look for their own solutions and not necessarily follow the narrow track laid out for them. Of course an engineer might do this too but their training does not emphasize this approach as strongly.

Comment More than just money (Score 1) 370

During the age of Columbus, any schmuck with a ship could go out exploring.

No they could not unless they had the backing of someone wealthy to pay for the ships, equipment and salaries needed. However they were willing to pay for it because while it was expensive and dangerous they were motivated by a variety of things: hope of treasure to plunder, land to lay claim to and knowledge of distant peoples and creature to learn about.

It's a bit sad that someone who calls themselves a scientist thinks that the only reason anyone will ever do anything is purely for money. The ability to make money will certainly be what causes space exploration to take off in a big way but, as with any frontier be it in knowledge or on the map, the first explorers are often motivated by things other than how much money they will make...that tends to follow later.

Comment Scientists trained to ask "Why?" (Score 1) 494

There is obviously a correlation between being dateless and becoming a terrorist.

It has to be more than that: computer scientists and physicists are not known for their terrorism or their dating (well unless it's radiocarbon dating).

Personally I think it has more to do with the fact that engineers are trained to follow rules and so it attracts people who are happy to follow rules without necessarily questioning them or completely understanding the reasoning behind them.

On the other hand scientists will question every rule you give them and even when they believe that the rules might be right they will still spend their time poking them to see if they really do apply everywhere....which is why we can be so annoying at times especially to those trying to use toxic, religious dogma to persuade others to commit irrational and immoral acts.

Comment Re:Litigious Much (Score 2) 815

You could also say "The big bang theory began with the Belgian Army", because he was also in that.

Which would only be relevant if people were complaining that the Belgian Army was an enemy of science. However given that at the moment they seem to be deployed on the streets of Brussels trying to keep religious fanatics from killing people I don't think this is something we need to worry about.

Comment Re: ...and the Science would have been Better (Score 1) 96

Did I claim that it meant that anywhere? In the simplest possible way it is wrong because the physics involved is at a minimum 13.8 billion years old since it has at least existed since the Big Bang. While you might regard this as pedantic in science details matter especially when communicating it. It's one thing to sacrifice accuracy for simplicity when communicating with the public but doing it unnecessarily like this is just sloppy and unscientific...and sadly something this writer who shamelessly self-promotes on Slashdot does far too often.

Comment ...and the Science would have been Better (Score 0) 96

Plus had that been the case we would not have a stupid title referring to "4.5 billion year old physics" which "StartsWithABang" would have known if he had any decent knowledge of physics, is a silly thing to say because the laws of physics are invariant with time. This is actually an incredibly fundamental point of physics since this symmetry with respect to time gives us conservation of energy.

Comment Marketing not greatness of product (Score 2) 249

If NeXTSTEP was so great, then why didn't it become as popular as Windows?

The success of something does not depend solely on how good it is. How well it is marketed plays a huge role as well. I will freely admit that Bill Gates is a world class genius when it comes to marketing software. When it comes to writing well designed, easy to use software his ability is far more modest.

History is littered with examples where marketing has triumphed over technical greatness e.g. VHS vs. Betamax, the Sony mini-disc, the incandescent light bulb (invented by others marketed by Edison), Acorn Computers (who developed ARM in the late 1980's) etc. It's very common for better products to lose to better marketing - Just look at the film industry the Oscar for best picture is not handed out to the highest grossing film every year is it? So by all means admire Windows for the way it was marketed but if you are going to claim it is an excellent product you need to provide more evidence than just the volume of sales.

Comment Channel Bonding (Score 1) 91

Until then, everyone will be capped at 1gig per device.

That's not actually correct. Thanks to channel bonding I have a Synology Disk array which has 4 Gbps connection all using inexpensive consumer grade hardware. Channel bonding 1Gb is far cheaper than 10Gb ethernet although with the new 10Gbase-T format this too is now becoming more affordable.

Comment Summary wrong: Uber is NOT being sued (Score 1) 210

Actually that was my immediate reaction but while I know we are not expected to read the article I did at least think that the submitter should. The taxi owners have NOT filed a law suit against Uber as the first line of the summary says, they have filed a law suit against NYC (as the title says) over them allowing Uber to operate. This seems to have some merit.

If you are going to create an artificial monopoly and charge people a lot of money to take part in it then they do have a grievance if you suddenly let others take part without paying the same fee. Of course if they had not created an artificial monopoly in the first place, or at least kept the costs to take part reasonable and the service quality high, then this would not have been an issue.

Comment Re:A lot simpler: Energy (Score 1) 378

If you have enough energy to accelerate something up to 90+% the speed of light radiation is not much of an issue because for far less energy you can create a extremely strong magnetic field which will deflect the hard to block charged, hadronic particles and for photons you can shield. The time to accelerate is something I'd not thought - at 1g it's a month to 10% the speed of light so for a gamma factor of 10 your estimate seems reasonable. You could cut this down by accelerating at 2-3 g but this would be hard on the crew and still mean a significant amount of time would be spent accelerating and decelerating.

However the biggest problem is still the generation of sufficient energy and the ability to use it for propulsion. However this is at least possible without violating any of the fundamental laws of physics as we know them which FTL is not and even then this is really only an issue for interstellar distances. Within the solar system the problem really is just energy generation.

Some people have a great ambition: to build something that will last, at least until they've finished building it.