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Comment: Re:They can produce tritium at fission plants (Score 1) 305

by amazeofdeath (#47735479) Attached to: If Fusion Is the Answer, We Need To Do It Quickly

Again, you have no point:

- If you can produce plutonium, you can produce tritium (in fact, you'll produce tritium in any water-cooled reactor).

- The relative amounts of Pu-239 and Pu-240 is a function of burn time. If you have a nuclear reactor, you can control the burn time, producing the isotope mix you prefer. Pu-239 doesn't need to be enriched with centrifuges or other methods like U-235.

- If you don't have plutonium production capability, but can get enough plutonium to make a bomb, getting tritium is trivial. Tritium has been widely used, and for example missing exit signs generate a large portion of NRC's "missing radioactive material" alerts.

- Pu-240 was discussed above. Its presence in large concentrations complicate bomb design because of its high spontaneous fission rate and shorter half-life compared to Pu-239.

Comment: Re:They can produce tritium at fission plants (Score 1) 305

by amazeofdeath (#47726509) Attached to: If Fusion Is the Answer, We Need To Do It Quickly

I fail to see any point in your reply:

- All explosives have impurities. A uranium-based nuclear bomb is not 100 % U-235, it's enriched to somewhere around 90 % U-235. A block of TNT is not 100 % trinitrotoluene, there are impurities too. The impurities sometimes contribute to the outcome, but in nuclear weapons, it's the U-235 or Pu-239 that's brought to critical density condition to make the explosion possible.

- Working nuclear weapons have been designed without D-T boosting; in fact, no nuclear weapons program to date has began with such a boosted design. The boosting is a complication from engineering point of view.

- It's access to weapons-grade uranium or plutonium that's the problem from proliferation point of view. If you have working nuclear plants, like Japan does, access to tritium is a trivial addition.

Comment: Re:They can produce tritium at fission plants (Score 2) 305

by amazeofdeath (#47709891) Attached to: If Fusion Is the Answer, We Need To Do It Quickly

Pu-240 isn't used for nuclear weapons, though. The isotope for bombs is Pu-239, with a critical mass of ~10 kg. The spontaneous fission rate for Pu-240 is much higher than for Pu-239 (about 30000 times as high), and it's also more highly radioactive, leading to additional problems with keeping the bomb cool before detonation.

The critical mass isn't that important in "normal" bomb designs. For example, Little Boy and Fat Man weighed about 4500 kg (the former being a couple hundred kg lighter), so a difference of a few tens of kg in the critical mass is negligible when compared to the total bomb mass. However, if you are aiming at the smallest possible physical bomb size, plutonium has a big advantage. Compare two actual weapons with ~1 kt yields, W33 and W54. The former is a gun-type uranium device, weighing something like 110-120 kg, based on the estimates I've seen, and it's an artillery shell with a base diameter of 20 cm and length of roughly 70 cm. The latter is a miniature plutonium implosion device with a weight of 23 kg and a diameter 27 cm.

Earth

IPCC's "Darkest Yet" Climate Report Warns of Food, Water Shortages 703

Posted by timothy
from the c'mon-fellas-lighten-up dept.
The Australian reports that "UN scientists are set to deliver their darkest report yet on the impacts of climate change, pointing to a future stalked by floods, drought, conflict and economic damage if carbon emissions go untamed. A draft of their report, seen by the news organisation AFP, is part of a massive overview by the Intergovernmental Panel on Climate Change, likely to shape policies and climate talks for years to come. Scientists and government representatives will meet in Yokohama, Japan, from tomorrow to hammer out a 29-page summary. It will be unveiled with the full report on March 31. 'We have a lot clearer picture of impacts and their consequences ... including the implications for security,' said Chris Field of the US’s Carnegie Institution, who headed the probe.

The work comes six months after the first volume in the long-awaited Fifth Assessment Report declared scientists were more certain than ever that humans caused global warming. It predicted global temperatures would rise 0.3C-4.8C this century, adding to roughly 0.7C since the Industrial Revolution. Seas will creep up by 26cm-82cm by 2100. The draft warns costs will spiral with each additional degree, although it is hard to forecast by how much."
Programming

Does Relying On an IDE Make You a Bad Programmer? 627

Posted by samzenpus
from the speak-up dept.
itwbennett writes "Writing about his career decisions, programming language choices, and regrets, Rob Conery says that as a .NET developer he became more reliant on an IDE than he would have with PHP. Blogger, and .NET developer, Matthew Mombrea picks up the thread, coming to the defense of IDEs (Visual Studio in particular). Mombrea argues that 'being a good developer isn't about memorizing the language specific calls, it's about knowing the available ways to solve a problem and solving it using the best technique or tools as you can.' Does using an IDE make you lazy with the language? Would you be better off programming with Notepad?"

Comment: Re:All scientific conclusions should be questioned (Score 2) 316

by amazeofdeath (#45161937) Attached to: How Science Goes Wrong

No, the AC set up a straw man in his "experiment". It ignores the higher thermal capacity and lower heat conductivity of humid air compared to dry air, for starters. He may have a PhD in physics (so do I), but that doesn't excuse him from the fact that CO2 has been shown to be a greenhouse gas.

Comment: Re:Detriment caused (Score 1) 115

Equipment that would join an unknown network without any user interaction at all?

Yes. You seem to be pretty out-of-date in normal laptop and other WiFi-enabled systems.

there's no such commercial products that'll crack WEP without user configuration

Sure there are, but the people selling them aren't exactly going to advertise them in your local store.

I thought putting up a disclaimer (as there are "commercial" products for pretty much everything), but I thought that it was clear from the context. Your OEM laptop will not crack WEP out-of-the-box.

Comment: Re:Detriment caused (Score 1) 115

Having a laptop open in your car does that, it's nothing special. My ages-old iBook would connect to any open WiFi network, were I using the default settings. Picking up an unencrypted connection is trivial, whether by purpose or by accident; connecting to a WEP-encrypted WiFi network requires some specific effort. You are building up some ridiculous straw-man here: There's a lot of equipment that will connect to any open WiFi network in out-of-the-box configuration, but there's no such commercial products that'll crack WEP without user configuration.

Books

Iain Banks Dies of Cancer At 59 141

Posted by samzenpus
from the rest-in-peace dept.
An anonymous reader writes "BBC News is reporting that Iain Banks, best known for his Culture series novels and The Wasp Factory, has died of cancer aged 59. It had been announced several months ago that he was suffering from bladder cancer, and he had stated his intentions to spend his remaining time visiting places which meant a lot to him after marrying his partner."

Comment: Re:And if one can't believe? (Score 1) 931

You've yet to show that Krauss holds that view. Abolishment through education (as higher education correlates with less belief in sky-fairies) seems to be what he advocates.

Huh? He want's it labelled child abuse.

No. He wants religious indoctrination of children to be labeled as child abuse. That is not equal to criminalizing religion.

It's also a blatant fallacy that "higher education correlates with less creation". In fact the opposite is true if a person pursues an education in Philosophy.

Wrong. 72.8 % of philosophers being atheists is much, much higher than the average in the US. Link to a very recent study: http://www.preposterousuniverse.com/blog/2013/04/29/what-do-philosophers-believe/

So, you couldn't find anyone giving those odds? Winning in lottery is a true/false question, how can anyone set those odds as anything different than 50/50? This is something that you seemingly fail to grasp.

Wrong, maybe you should go back and take a basic statistics class. Either that, or you need to stop twisting facts to support your beliefs, which would be the most advisable course of action.

But that's what you claim: The existence of a creator is a 50/50 chance situation, with nothing possibly skewing those odds to either direction. You just can't see how taking that stance in the lottery analogy leads to an absurdity. I'm not twisting any facts. I just find your unsupported 50/50 claim ludicrous, and tried to show how a true/false situation can mean anything but 50/50 odds.

The experiment comes from Philosophy first!

I don't really agree with this. The ancient Greek philosophers got several things wrong, when they didn't do the experiments they could have done.

You have a concept of something, you build a model to see if you are correct. The concept and thought process allowing you to build the experiment is Philosophy.

And that specific philosophy is called science. Philosophy in general lacks the self-correcting feedback that science has between the experiment and the theory. But, a theory begins with observations; usually such observations that aren't explained by existing theories.

I'm doubtful that you have a PHD.

Not my problem. My credentials are verifiable, but I'll prefer anonymity, as I don't try to make it an argument from authority. While you are on your trip to visit the cosmologist, find a couple of experimentalists and ask your philosophy question.

Einstein was not too happy about how Science was used against Japan either was he?

And? Science doesn't provide moral guidance in this sense. Though I'd like to know Einstein's view on atom bomb vs. invasion of the Japanese main islands, as the latter had a lot higher projected death toll.

We have found giant skeletons, which means that David and Goliath is very possible.

:D You do know that the giant skeleton was a hoax?

We have found all kinds of validation that a major world wide flood happened, so it is possible that this event occurred.

No. We have found evidence of local floods, but no evidence for a global one. And there isn't enough water on earth for a biblical flood.

Parting the Red Sea has been shown to have some merit with natural phenomenon, so while it may not have been a guy with a staff it could have happened.

Wind driving the water off from such a large area is a stretch, and it hasn't been demonstrated in reality. But yeah, I'll grant that it's not entirely impossible. The problem then is that you are trying to use a natural phenomenon as evidence for the supernatural.

You make a false claim that it's all horrible and all wrong.

I did not make that claim, I said "much". There are also the boring parts (genealogies, *yawn*), and even a few reasonably entertaining stories.

I haven't claimed that BB theory is right, as no theory is ever right. They can only shown to be wrong; until that happens, the prevailing theories are our best models to match the universe we observe. Did you read the Scienceblogs page I linked to? Where were the numerous BB theories presented there?

That whole paragraph reeks! Some theories are always wrong and should never be pursued.

What does that have to do with theories not being proven right? Of course some theories are so wrong that it's waste of time to study them, but to recognize theories that are wrong usually requires developing the theory to a stage where it can make predictions, and then making the experiment or observation.

Prevailing theories are often wrong, sometimes to the point of never being pursued Hitler's theories of a supreme race for example (which were heavily embraced in the US). Countless theories have been right enough that we can progress in knowledge because of them. Einstein's theory of relativity for example. Big Bang sits somewhere in the middle of those two theories.

That's an absurd claim. BB theory is based on Einstein's general relativity, which predicts non-static (that is, expanding or contracting) universes. If you want details, check out FLRW metric. "Race science" or eugenics, on the other hand, was politically motivated and twisted to produce "results" that the ruling parties wanted. It was more an ideology.

Yes, I read the blog but no, my opinion that Expanding Vacuum is a much better theory does not change.

Would you finally describe the EV theory? Google doesn't recognize it, and as I said earlier, the small bits you've inferred don't point to a theory which I've heard of.

It also does not change the fact that I can go to numerous locations to read variations in the Big Bang theory which also claim to be right.

You have to substantiate this claim (actually two claims: 1) different BB theories, and 2) claim to be right).

The next two points mean that you don't know Krauss's work at all. Again, you use fallacy to deny your own ignorance.

But Krauss's work is mostly about BB cosmology. Are you referring to A Universe from Nothing? A popular account of how the Big Bang could have happened.

Philosophy is required for every part of education. Rhetoric, Logic, and ethics.

Perhaps. But those are also well integrated into other disciplines, so math covers the logic part, for example.

Since you use fallacy so much, you seem to be extremely devoid of philosophical training.

Yet you seem to be leading at this front, starting the very post I'm replying to with a fallacy.

If philosophy is taught early, people are smarter. This is a fact, shown by over a thousand years of teaching in this way.

Evidence? I'd rather expect that education in general makes people smarter, and starting from an earlier age gives better results.

It should be taught young, not as an elective only in higher education. It has no precursor except for language which can be taught at the same time.

The problem here is you try to claim that philosophy, and only philosophy, can give these tools. In reality, those tools are in the sciences and math, and only in those disciplines philosophy can lead to actual knowledge about our world. You need to combine the philosophy with experiment, i. e. do science, to produce actual results. You can see this in the study I linked above: The philosophers don't have a consensus on any of the questions asked (external world comes closest, with 80 % agreeing with it). So while philosophy can provide us some useful tools, and studying it surely won't hurt anyone, it doesn't seem to be that useful alone.

Can I perform physics without Math, Algebra and Trigonometry? For more accurate Physics, I would also need Calculus right?

Yes, math is an integral part of physics. But if I calculate the trajectory of a projectile, am I doing physics or math? Or fit a theoretical model to my data? In the same vein, I'm not philosophizing when I try to deduce the magnetic interactions in a sample from different datasets.

Comment: Re:And if one can't believe? (Score 1) 931

While I don't doubt that you can find people with extreme views such as abolishment of religion, that's not what atheists in general demand. The demand is to keep the beliefs inside the believers and out of the society.

Were we not discussing Krauss that has just such a view? Randomly poll atheists and see how many agree with him, and don't see their belief as hypocritical.

You've yet to show that Krauss holds that view. Abolishment through education (as higher education correlates with less belief in sky-fairies) seems to be what he advocates.

And yet you can't give an example of your 50/50 claim. Not that it matters, philosophy is pretty worthless in evaluating claims of existence.

It becomes rather pointless to establish a different ratio when we know we can never prove either side is correct. It's a true or false question. How does any rational person set the odds any other way?

So, you couldn't find anyone giving those odds? Winning in lottery is a true/false question, how can anyone set those odds as anything different than 50/50? This is something that you seemingly fail to grasp.

The second half of that is absolute rubbish! Every scientific theory starts with a Philosophical evaluation! Every single one! Why do you think most scientists have PHDs? You do know what PHD is an acronym for don't you?

As a PhD, I'll have to inform that you are wrong. Every scientific theory begins with experimental data. This is why, say, the ancient Greeks theorizing about atoms didn't produce anything usable.

I've often wondered, how many of those people would have believed in a god, had they not been indoctrinated during their childhood (I don't claim that all of them were). I have hard time believing that anyone would come up with the Christian God and dogma (virgin birth and such) just starting from first principles and working in vacuum.

You are showing a great amount of ignorance of history here. Read up on Sumeria and Ancient Greek beliefs. It's not difficult to come up with any modern religion based on previous beliefs.

That's part of my point. The religious dogma seems like fairy-tales built on older fairy-tales. I did say "in vacuum", i. e. working without knowledge of the current and past religions.

Much of what is in the Judea Christian old testament seems to have some truth to the shape of the world also. If some does, perhaps you have been fooled into thinking there is no truth in anything except for what you have been taught to believe?

Much of the Old Testament is factually wrong or pretty hideous stuff morally. I don't know about truth, but science has been the only tool to give us something usable.

Einstein did believe in a creator, but was not a practicing Jew and did not believe what most Religions did or taught about the creator. You do realize that all of his writings are on the Smithsonian web site and translated to English, so you could easily check facts for yourself right?

So show me wrong with actual quotes.

How can you possibly agree with a disproportional set of conflicting information?

What conflicting information? We have talked about inaccuracy in measurements of parameters, like the age of the universe.

I'm not trying to claim the theories are bad, but pointing out the fact that there are numerous theories of the same name and none of them are the same. To claim BB is right means you have never read on what BB is.

I haven't claimed that BB theory is right, as no theory is ever right. They can only shown to be wrong; until that happens, the prevailing theories are our best models to match the universe we observe. Did you read the Scienceblogs page I linked to? Where were the numerous BB theories presented there?

You must also answer "who's BB" theory is right, who's numbers for dark matter and energy are correct, etc.. etc...

You still don't get it: Parameters are part of a theory. Using different parameter sets within a theory doesn't make different theories.

Also remember that if the expanding vacuum theory is correct, BB never happens.

What "expanding vacuum theory"? It's just your misinterpretation, as far as I can tell.

The Universe slowly expanded from a small point of space.

Yes, that's the starting point of BB theory.

In addition to making BB defunct, it ages the Universe immensely.

How does it do that, when it's part of the BB theory?

You still seem to believe that there is only 1 theory of Big Bang after being shown that there are differences between who you ask about BB theory!

Show the differences, then. All you have shown so far are different parameters used in the BB theory.

If you are not using the Earth and Moon's mass, you are not modelling the Earth and Moon are you?

To what accuracy do we know those masses? Does using different values within the known inaccuracy produce different Newtonian gravity theories?

And if I said that magic dragons pull the moon through the sky (which is the equivalent of Dark Matter and Dark Energy) I'm not modelling anything real am I?

Again you show your ignorance. Dark energy and dark matter are placeholders for causes of things that we observe, but don't have a proper theory for. For example, the Bullet Cluster gives pretty much direct observation of the dark matter, but we still don't know what the dark matter is, exactly. We only know some things that it isn't. The difference to your magical things is the dragons aren't needed to explain the moon's orbit.

Again, if Expanding Vacuum is right then all big bang theories are wrong!

Again, you are only talking about something that you have invented, not the actual BB theory.

If a massive explosion happened to cause the Universe's expansion, then at some point it must contract.

But the BB theory doesn't claim a massive explosion. That's only an analogy. And I don't see how an explosion would lead to contraction; I've never observed the gasses released when firing a gun contract back into the barrel or case. It's all a straw man you are building here. And if you are talking about running time backwards so that expansion turns into contraction, didn't you just above say that your imaginary expanding vacuum theory starts from a small point?

Oh, so you explain all the discrepancies away by dismissing other people's work for them. Sorry, that does not work.

It'd be helpful if you showed those discrepancies instead of your own misunderstandings.

Descartes stated "I think therefor I am" which discounts the possibility that you are a computer program. Yes, we can dismiss the theory in a very simple fashion.

Is this the level of sophistication that 30 years of philosophizing has given you? What if you are only programmed to think that?

You claimed to know some of Krauss's work, I guess that was not true? Go read Krauss's books, bigotry aside the science is rather good.

The problem is that nothing in Krauss's work resembles your expanding vacuum, as opposed to the BB theory.

I spelled that out very clearly, and in fact you comment in what I stated.

It is clear that you can't answer this question.

Philosophy is an elective in College, it's not required.

So is physics, at least when talking about modern level (say, the level of 1900s like quantum mechanics). So?

If it's worth hacking on well, it's worth hacking on for money.

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