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Comment: Re:It seems to me... (Score 1) 425

by delt0r (#48026237) Attached to: The Physics of Space Battles
There is nothing gravitic (what ever the hell that means) about optics. We have diffraction limited optics that are many meters across. We can right now send well focused beams huge distances. Sure we don't use huge power because these are not weapons.

In fact the hard part of lasers in space is not even getting powerful one. Its the fact that even a perfect laser is not all that efficient (from the physics). So you have a huge amount of heat to dump, or your space ships melts.

Comment: Re:It seems to me... (Score 4, Informative) 425

by delt0r (#48018123) Attached to: The Physics of Space Battles

Likewise, perhaps *we* can't focus a laser today, but that's not an inherent limitation of lasers even by today's known physics,

In fact we can focus lasers to within the limits imposed by physics. That is diffraction limited optics and Gaussian beam optics. Real lasers and optics get very close to these limits.

Long story short its all about the size of your laser, or rather aperture. Lets assume a 500nm laser with a 1 meter wide aperture and we assume we want a spot size 1 meter or less. From the math that means we can focus that good out to a range of just over 3140km. In the middle the beam size is about 70cm. At a range of 4700km the spot size is about 2meters. These ranges scale with the square of aperture size with the caveat that we only focus to the aperture size. So a 2 meter one has 4 times the range where the spot size is 2 meters or less. It is also proportional to wavelength.

Comment: Re:Third option (Score 1) 421

by delt0r (#48013919) Attached to: Users Report Warping of Apple's iPhone 6 Plus
The phone would then make a much better penetrator when thrown in anger. Could go the whole hog and use depleted uranium. Unlike tungsten, it will perform considerably worse than even aluminium for bending resistance but be even more uncomfortable in the pocket, but has superior dense penetrator performance.

Comment: Re: But is it reaslistic? (Score 1) 369

by delt0r (#47814593) Attached to: Islamic State "Laptop of Doom" Hints At Plots Including Bubonic Plague
Well in the H1N1 case the WHO did launch an investigation as to why H1N1 was declared a pandemic. Turned out that 2 advisers that pushed for it had a substantial tamiflu stake. The Data simply never supported it at all. In fact it was a more mild flu season than the previous year. No it wasn't because of tamiflu.

This also illustrates some very serious problem when studying these things. The data is of such poor quality, mostly because doctors collect it, that it is hardly usable at all. For example in NZ, if you had any flu like symptoms that year, it was reported as a H1N1 case. Clearly that is not how it works.

Bird flu and SARS where very similar in that 1 perhaps 2 quite young people died and then everyone jumped on the "new disease" bandwagon. A post analisis of the data didn't suggest there was anything out of the ordinary, and some countries did flat out ignore it because they didn't see any support from the data (Austria for example). For example the fatality rate of SARS was suppose to be 3%, but only people sick enough to get admitted to hospital where tested to see if they have it. Many people could have had it with much milder symptoms. BTW i worked directly on some of the SARS data, and well NDA and stuff i can't say much other than its was pretty poor quality.

Make no mistake, we need an organization like WHO (we get a lot of data from them in fact). And we need to have people on the lookout for pandemics. But we need to base these decisions on data, not emotion. Note data may not be serology tests or DNA test. But old fashion symptom progression, disease state and fatality rates with responses to treatments. ie stuff even a 3rd world hospital would have if the doctors would bloody well write down what they thought, did and measured. Something as simple as temperature rather than a blanket statement of "fever".

Of course a bunch of tests/measurements on the general public "background" would also be useful. But this is expensive and hard to do properly since you can't force it on people and you get selection bias and also a bunch of ethics issues.

Comment: Re: But is it reaslistic? (Score 1) 369

by delt0r (#47800435) Attached to: Islamic State "Laptop of Doom" Hints At Plots Including Bubonic Plague
While this is true. Even with decades of experiments, they are not going to get anything worse than what is out there already, and most likely more benign, since its no longer evolving under pressure from our immune system (that "evolves" on the order of days and weeks). Sure they could get hold of an Ebola patent and convince them to take a world tour. That is about as effective as they can be. Or blow them up in some very blood spattering way (not sure that would work however).

But a advance lab to create some superbug in some super Crag Venter style is hardly credible. Using evolution to do the dirty work is even less so.

To give you some examples without just a list of reference to papers you probably can't get access too. Common yeast is not the same as lab yeast. Lab yeast does not clump like wild yeast. This is purely unintended selection over the generations with particular lab protocols. Cool eh. We can get some lab strains to replicate quite fast in some media at 37C. Only it turns out that a lot of the "optimal" temperature thing is based again on unintended selection on strains optimized for the most common default lab environments.

We are currently working on tamiflu resistance in evolutionary experiments. Yes we observe resistance in only a few dozen generations. But this already happened in the real world (yea tamiflu more or less never worked properly anyway). We also observe hitchhiking of many things that don't look too good outside the media used. In fact we have to control for the fact that things happen on this media. We let there be a few 100 generations on the media so we don't confuse what is just selection for that media.

And of course all that happened without the presence of a rapidly responding immune system. Now move it into a real host (different media) with a immune system, and you find these lab strains just die out. We see this with lots of different systems by the way.

Bioweapons are even worse than dirty bombs. The threat is not from a terror organization or a stupid scientist. But just old fashion evolution. These make poor bio weapons. But a new pandemic on the scale of Spanish flu would be expensive. However not as devastating as the movies make out. In fact many believe a disaster movie level pandemic is impossible due to the tradeoffs that must be made in the design of the bug/virus.

But don't get me started on these recent H1N1 or bird flu bullshit. I will rant all day.

Comment: Re: But is it reaslistic? (Score 1) 369

by delt0r (#47799951) Attached to: Islamic State "Laptop of Doom" Hints At Plots Including Bubonic Plague
Err not really. They have taken many decades to really have any impact, and yet they are very poorly selected for patients without treatments. In other words they have these negative mutations with them as well. Also quite a lot of them are because people don't follow treatment programs properly. Tuberculosis is a prime example there.

And why should those environments be even remotely as effective at creating a bioweapon as deliberating creating an environment where the dominant selection processes are for bioweapon potential?

Because evolution just does not work the way you think it does. You can't use evolution to select for a bioweapon, because a bioweapon is not selectively advantageous. Killing your host does not help you perpetuate. Living asymptotically in a host is not a weapon. Getting something that works well in media, has been selected to live well in media and not outside it. We see this all the time. We have math models of it. We have done evolutionary experiments and observed it.

Bioweapons just don't evolve. They must be designed and created. They also don't work well at any rate. Russia and the US didn't agree to stop pursuing them because they thought they could work. They agreed because they had figured out that they just don't work well at all.

Comment: Re: But is it reaslistic? (Score 1) 369

by delt0r (#47799463) Attached to: Islamic State "Laptop of Doom" Hints At Plots Including Bubonic Plague
It really doesn't work that way, it really is much much harder than that. Also 1000s is with mutagens. You also get bad mutations "hitchhiking" along for the ride, for example ones that reduce virulence. In other words it is only better in the presence of the drug. The other strains would by far out compete it.

Consider how many generations are exposed to these treatments in the real world. Yet we don't see new "bioweapon" strains popping up all the time. And we don't precisely because it really doesn't work that way.

Comment: Re: But is it reaslistic? (Score 1) 369

by delt0r (#47795541) Attached to: Islamic State "Laptop of Doom" Hints At Plots Including Bubonic Plague

OTOH, it's far easier to cultivate bacteria than viruses. For example, Yersinia pestis, the bacteria that causes bubonic plague can be grown in a modified agar gel [] with no need for host cells of any kind. And it's pretty easy to breed in resistance to anti-biotics by exposing the bacteria over many generations to all the anti-biotics in use at doses where a small part of the colony survives.

Working on such data is my day job. It is not even close to as easy as you describe often needing 1000s of generations or more, and you end up with something that is antibiotic resistant *on agar*. Your host is not such a simple media.

"More software projects have gone awry for lack of calendar time than for all other causes combined." -- Fred Brooks, Jr., _The Mythical Man Month_