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Comment: Re:So ... (Score 1) 213

by radtea (#47671833) Attached to: How to Maintain Lab Safety While Making Viruses Deadlier

The hubris of thinking "it's OK, I'm a trained professional, nothing bad can happen" is mind boggling.

What is mind-boggling is that anyone takes a virulently anti-science organization like the dishonestly-named "Bulletin of the Atomic Scientists" seriously as a source of news about anything.

All you have to do is look at the source, and dismiss the claims as hysteria and lies.

This is not to say there might not be a story here, or something worth discussing, but until it is sourced from something other than an outlet for anti-science, anti-technology political shills it is all noise and no signal.

Comment: Re:Why can't it just be one mass? (Score 2) 74

by radtea (#47667651) Attached to: Why Hasn't This Asteroid Disintegrated?

The article doesn't explain why the idea of this particular body being one mass instead of a rubble pile has been dismissed. Is there a good one?

Asteroids are believed to be aggregations of relatively loosely bound matter. They have likely experienced some local melting due to collisions, but it is very unlikely that they ever were entirely melted into a single mass. As such, they are quite peculiar bodies, much less akin to a mountain than a pile of rubble, and they likely aren't even all that close to a pile of rubble because the individual components they are made from were never part of a larger, more coherent body.

If you think about asteroid formation, you have to start with dust that accretes into small pellets, which then collide to form semi-melted rock-like-things, which then clump into asteroids (all the while suffering more collisions which produce local melting but not whole-body melting of the kind planets experienced.) This is all a consequence of the collisional statistics and dynamics in the early solar system.

So the proposition "Asteroids are loosely bound" is pretty plausible, and ones with high spin are therefore interesting because require us to revisit that plausibility, and who wouldn't want to do that?

Comment: Re:That's not what van der Waals is! (Score 1) 74

by radtea (#47667627) Attached to: Why Hasn't This Asteroid Disintegrated?

Every time I hear someone explain lift with "air on the top of the wing has to move faster, so... lift!" I want to...

There's nothing at all wrong with that explanation. It is neither better nor worse than any other explanation that is less than a full solution to the Navier-Stokes equation, and it provides a naive and surprisingly practical guide to interacting with airfoils, which the vorticity explanation, for example, does not.

Comment: Re:Space Drive or Global Warming? (Score 4, Informative) 315

by radtea (#47627415) Attached to: Why the "NASA Tested Space Drive" Is Bad Science

Except none of your points applies to climate change.

The effect is robust: there was a whole independent project to determine if the thermodynamically meaningless "global average temperature" is increasing. It is:

The threshold of measurement is around 0.5 C for a single station, and we have an effect that is about 1 C over the past 100 years. Not as big a margin as one would like, but difficult to ignore. And growing.

No one has produced any results that show the instrumental temperature record in the past century is not real. There are debates about causes, but the reality of the phenomenon is not in doubt.

Everyone who has looked at the question agrees that there is about a 1.6 W/m**2 addition to the Earth's heat budget from anthropogenic CO2, so clearly when taking the "positive cases" there is still good agreement.

There are large and legitimate areas of disagreement with regard to climate change (far more than the moron, anti-science, "the science is settled crowd" would have you believe) but the basic phenomenon, unlike the EMDrive, is not just consistent with but actually required by the laws of physics.

Finally: the summary is terrible, even by /. standards. The article does not point out any errors in the experiments. Rather it points out that reporters have been lying about the experiments, pure and simple. That is not the fault of the scientists, who honestly reported their null results.

Comment: Re:String theory is not science! (Score 1) 259

by radtea (#47609423) Attached to: The Man Who Invented the 26th Dimension

but since when has any self-respecting scientist been led away from a beautiful hypothesis by pragmatism? Much less a physicist?

More frequently than you might think.

I highly recommend Lisa Randall's "Warped Passages" as a fairly recent meditation from a working physicist on the strengths and weaknesses of multi-dimensional theories, as well as some of the background on what motivates them.

The short story is that higher dimensions make it easier to generate universes like ours, which are almost flat gravitationally and have this ridiculous difference in scale between gravity and everything else. Regular 3+1 dimension Standard Model physics requires a ridiculous level of fine-tuning for this to happen, so it is interesting to look for deeper theories where these features arise naturally.

The problem with String Theories in particular--and as other posters have pointed out it really is a family of theories--is that they are almost useless for "model building", which is the activity of generating simplifications we can actually calculate with to describe the world as it is today vs the world as it was a few Planck times after the Big Bang.

So while string theory is neither "untestable in principle" nor "designed to resist testing" it is "naturally test-resistant." Some simpler variants--including a rather elegant heuristic model that Randall herself co-created--have been killed off by the LHC, but the diversity of possible low-energy models enabled by String Theory is so large and heterogeneous that in practical terms they cannot all be falsified.

In the meantime, String Theories continue to take up an inordinate amount of theoretical physicist's time and effort, and there have been fairly senior voices raised in concern about this, particularly because it has been going on for so long that we may end up with a generation of theorists who have never done anything but string theory and have come to the conclusion that it won't work.

Rather than waiting for this Big Reset, it would be nice if we started spending more time looking at non-stringy alternatives.

Comment: Re:Van Braun built weapons for Nazis (Score 3, Interesting) 165

by radtea (#47579763) Attached to: Was America's Top Rocketeer a Communist Spy? The FBI Thought So

Then he came to the USA, and played the same con on Congress to fund his continued work here.

So in your view von Braun was an amoral, self-agrandizing liar who was willing to actively engage in the selection of slave labour working in death camps to build rockets that killed thousands of strangers just so he could play with cool toys? Because that's what you're describing.

I say "self-agrandizing" because everything that von Braun wanted to do would have been done without him, without the 12000 dead slave labourers, without the 9000 dead British civilians.

I've had some pretty extreme scientific and technical ambitions in my time, but have somehow been able to realize many of them without killing people, and have given up the rest because: killing people. So I'm willing to pass judgment on von Braun in this respect: if he faced a choice between following his dreams and not killing people I'd have to say the latter is the far better choice.

Comment: Re:Vendor vs In House (Score 1) 209

by radtea (#47577529) Attached to: Ask Slashdot: When Is It Better To Modify the ERP vs. Interfacing It?

One of the key problems I've run into, not only in regards to ERP, but in general, is that when you outsource all of your development your future is in the hands of someone who doesn't have your companies best interests as their primary concern.

Even in those cases where you get a good service provider (which will depend on the specific people you've got working on your project much more than the company they work for, so anyone who says "Oracle = good" is missing the point) you still run into one of the most fundamental human problems: we suck at communication.

When you outsource something the degree of clear, concise, validated communication required is many times what is required for in-house development (where communication can still be a major problem). Capturing user needs and implementing them in a useful and user-efficient manner is hard enough with a high-bandwidth internal-communications channel. With outsourcing it is almost impossible for the people designing and building the system to get the information they need from the end-users.

So one question I would ask the OP is: how often do your provider's developers talk to your end users? (not your end user's managers, who don't have a clue what the system requirements actually are). If the answer is "never or hardly ever" then in-house is definitely the way to go, because your in-house team will have at least some chance of building a system that will serve end-user needs.

Comment: Re:FUD filled.... (Score 1) 212

It sounds like this transformer had its center tap grounded and was the path to ground on one side of a ground loop as the geomagnetic field moved under pressure from a CME, inducing a common-mode current in the long-distance power line. A gas pipeline in an area of poor ground conductivity in Russia was also destroyed, it is said, resulting in 500 deaths.

One can protect against this phenomenon by use of common-mode breakers and perhaps even overheat breakers. The system will not stay up but nor will it be destroyed. This is a high-current rather than high-voltage phenomenon and thus the various methods used to dissipate lightning currents might not be effective.

Comment: Re:Whelp. (Score 2) 139

by radtea (#47534355) Attached to: Siberian Discovery Suggests Almost All Dinosaurs Were Feathered

For me, the resistance comes when I look at the large reptiles of today which are descended from dinosaurs.They don't have feathers.

Which large reptiles are those? And which dinosaurs are they descended from? And how did dinosaurs, which were all killed at the KT boundary, manage to have descendents?

Dinosaurs are reptiles with their legs under their bodies. This makes them distinct from other reptiles (the kinds we have today, which are not descended from dinosaurs) which have their legs off to the side.

Mammals also managed the legs-under-the-body trick, and birds (which are descended from dinosaurs, unlike all modern reptiles, none of which are descended from dinosaurs, what with dinosaurs all being extinct without issue at the KT boundary.)

+ - Letter to Congress: Ending U.S. Dependency on Russia for Access to Space 1

Submitted by Bruce Perens
Bruce Perens (3872) writes "I've sent a letter to my district's senators and member of congress this evening, regarding how we should achieve a swifter end to U.S. dependency on the Russians for access to space. Please read my letter, below. If you like it, please join me and send something similar to your own representatives. Find them here and here. — Bruce

Dear Congressperson Lee,

The U.S. is dependent on the Russians for present and future access to space. Only Soyuz can bring astronauts to and from the Space Station. The space vehicles being built by United Launch Alliance are designed around a Russian engine. NASA's own design for a crewed rocket is in its infancy and will not be useful for a decade, if it ever flies.

Mr. Putin has become much too bold because of other nations dependence. The recent loss of Malaysia Air MH17 and all aboard is one consequence.

Ending our dependency on Russia for access to space, sooner than we previously planned, has become critical. SpaceX has announced the crewed version of their Dragon spaceship. They have had multiple successful flights and returns to Earth of the un-crewed Dragon and their Falcon 9 rocket, which are without unfortunate foreign dependencies. SpaceX is pursuing development using private funds. The U.S. should now support and accelerate that development.

SpaceX has, after only a decade of development, demonstrated many advances over existing and planned paths to space. Recently they have twice successfully brought the first stage of their Falcon 9 rocket back to the ocean surface at a speed that would allow safe landing on ground. They have demonstrated many times the safe takeoff, flight to significant altitude, ground landing and re-flight of two similar test rockets. In October they plan the touchdown of their rocket's first stage on a barge at sea, and its recovery and re-use after a full flight to space. Should their plan for a reusable first-stage, second, and crew vehicle be achieved, it could result in a reduction in the cost of access to space to perhaps 1/100 of the current "astronomical" price. This would open a new frontier to economical access in a way not witnessed by our nation since the transcontinental railroad. The U.S. should now support this effort and reap its tremendous economic rewards.

This plan is not without risk, and like all space research there will be failures, delays, and eventually lost life. However, the many successes of SpaceX argue for our increased support now, and the potential of tremendous benefit to our nation and the world.

Please write back to me.

Many Thanks

Bruce Perens"

Comment: Re: Just let me do brain surgery! (Score 1) 372

by radtea (#47519359) Attached to: 'Just Let Me Code!'

Of course brain surgeons don't "just do" brain surgery .... in any surgery, there's a ton of pre-operative work, investigation, preparation, paperwork, practice, etc

Most of which is not done by the surgeon. I've worked a lot with surgeons, and can assure you they are used to having other people do almost everything but surgery for them.

Surgeons are the equivalent of the "master programmer" team, which is a now mostly-obsolete team structure where there is one (or a very small number) of expert coders surrounded by a larger group of admin/build/whatever types who make sure the master programmer has nothing to do but code. It works on certain problems, but unlike surgery, the scope of what we expect software developers to do has grown far beyond what one person can handle in almost all interesting cases (I say this as a team of one who does everything from firmware to UI, but it is on a very narrowly defined embedded application that I've worked extremely hard to keep more-or-less within scope for a single very senior person.)

As far as we know, our computer has never had an undetected error. -- Weisert