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Comment: Observe, predict, test (Score 2) 364 364

by Attila the Bun (#49856463) Attached to: Have Some Physicists Abandoned the Empirical Method?

Observe, predict, test.

Nobody says *how* you should go about doing the "predict" part, so long as you test carefully afterwards. It happens that in certain fields of science, especially fundamental physics, prediction has become very difficult. And that's why we need a bunch of theoreticians developing wild new theories which we, the experimentalists, will then test. But as I said, this process isn't easy and takes some time. It takes time to develop the theory far enough to make concrete, testable predictions, and it takes time to develop the technology to carry out those tests.

Take string theory. Nobody in particle physics is under any illusion that this has been through the complete scientific process. String theory is not a scientific result, it is merely an intermediary phase in the discovery of something more complete than the existing Standard Model.

Comment: Parallax and perspective (Score 2) 191 191

by Attila the Bun (#48606055) Attached to: Jaguar and Land Rover Just Created Transparent Pillars For Cars
I was going to ask how they deal with parallax and perspective: the need to account for the position of the driver's head so the the projected image properly lines up with the scene beyond. But the images in TFA make it clear: they haven't. This is a mock up. Nothing has been created, and Jaguar - Land Rover hasn't the faintest idea how to make it work for real.

Comment: Re:Ok let me get this straight (Score 2) 103 103

by Attila the Bun (#48285837) Attached to: Physicists Identify Possible New Particle Behind Dark Matter

Or it might be time to start looking at other things entirely. Especially seeing as there has already been a considerable amount of work on finding 5th forces both attractive and repulsive When new theories start contradicting experimental data or start making statements that are untestable, at some point you have to drop back and say you have been barking up the wrong tree.

I'm not sure what you're getting at. Science follows a simple recipe: observe, predict, test. We observe that galaxies rotate in a manner that cannot be accounted for by our existing understanding of gravity and matter. A whole bunch of predictions have been made according to different ideas about how to account for galactic dynamics, from gas clouds to black holes to brown dwarfs to modified gravity to exotic particles. From time to time somebody comes up with a new idea to add to the list. Those predictions are being tested and eliminated, and so far the one that's holding up best involves exotic particles. You can be sure the more prosaic possibilities were studied first, but it turns out they have not done a good job in matching observations. But it will take time any many experiments to uncover the truth. Meanwhile we will continue to bark up all the trees that are still standing, and search for new ones to climb.

Comment: Re:Ok let me get this straight (Score 2) 103 103

by Attila the Bun (#48285217) Attached to: Physicists Identify Possible New Particle Behind Dark Matter

Not only are they inventing a new particle, but a new force as well ? Which is needed to explain how the new particles behave ?

If dark matter particles interacted with any of the known forces (apart from gravity), they'd interact with ordinary matter and we'd be able to see them -- in other words, they wouldn't be dark. Whatever dark mater is made of, it almost certainly involves a new and undiscovered class of particles. Most likely particles in that new class will couple to each other in new ways -- which is another way of saying they experience new forces.

Really this seems to be nothing more than an attempt to create an explanation that doesn't make predictions and is as removed from testability as possible.

Many of the less exotic ideas have been eliminated by experiment. Negative results don't make good headlines, but much progress has been made on the search for dark matter and the number of possible theories has been greatly reduced. There is a real need for new ideas of this type.

Comment: Re:Hardly Either Or (Score 2) 137 137

by Attila the Bun (#48237605) Attached to: Dwarf Galaxies Dim Hopes of Dark Matter

Frovingslosh is saying dark matter doesn't exist. He's wrong.

That's a very strong statement. I personally would say no more than "Something we don't fully understand is causing an effect".

Our statements are almost identical. The term "dark matter" is just shorthand for "something we don't understand, exerting a gravitational effect". There's also the possibility that there is no "something" and our understanding of gravity is wrong, but that has now been all but ruled out.

You spend 8 billion to get 100 million worth of R&D it's not a great use of funds.

This is a separate argument, but I'll answer it with two important points:

1. You can't put a value on fundamental research. The Higgs Boson in unlikely to have any direct application in the near future, but what about superconductors, or RF generators, or ion sources, or ultra-high vacuum techniques? All technologies which have been heavily developed for particle physics, and which have already found their way into industry. Even if you came up with a figure for the value of those technologies up to now, there's no way you can measure their future value. Yet future progress without them is unthinkable. All our technology is built on fundamental research, so if technology (and by extension, civilisation) is to advance so must fundamental research.

2. Could you develop the same technology more cheaply, without building huge science experiments? No. Of course not. Who would spend their whole career perfecting some obscure device if there wasn't a chance of participating in a great discovery? Industry just can't generate that kind of motivation.

Comment: Re:Hardly Either Or (Score 2) 137 137

by Attila the Bun (#48237201) Attached to: Dwarf Galaxies Dim Hopes of Dark Matter

Frovingslosh is saying dark matter doesn't exist. He's wrong. He's saying the effort devoted to finding out what it is is fruitless. He's wrong on that too.

The question of priorities is much more complex, and everybody has their preferences. As it happens large accelerators are delivering more and more-useful spinoffs than ever before: the technologies developed to build the most recent generation of accelerators have direct applications in industry and medicine. Some people claim the same technology could be developed more cheaply without the involvement of particle physics research, but so far nobody has figured out a way to make that happen.

Comment: Re:Aether (Score 5, Interesting) 137 137

by Attila the Bun (#48237039) Attached to: Dwarf Galaxies Dim Hopes of Dark Matter

Dark Matter is the Aether of the 21st century. Eventually we'll stop wasting money on finding it.

...and the enlightened explanation for galactic rotation curves will be, what?

There's strong evidence for the presence of unseen stuff in galaxies. It shows itself in its gravitational effects on the way stars orbit around galaxy centres. Either our understanding of gravity is wrong (an option on which money has also been "wasted"), or there is some invisible "dark" matter out there. Figuring out what that matter is will mark a huge advance in cosmology and likely determine the future direction of particle physics too.

If you feel that understanding our universe and our origins is wasted effort, then we will never see eye to eye.

Comment: Why is this a bash bug? (Score 2) 329 329

by Attila the Bun (#48018843) Attached to: Bash To Require Further Patching, As More Shellshock Holes Found

Why does bash have to worry about security? It's just a shell, a thin interface supposed to execute whatever commands it receives. Surely the bug lies with Apache et al. for not properly censoring the data they receive from outside and send to bash for execution.

I understand that the exploit works by appending malicious commands after a function definition contained in an environment variable. The environment variables aren't meant to contain anything more than the function, so executing the extra code is a bug. In that sense the bug belongs to bash. But the shells were never designed to be secure against this kind of attack, and as we're now discovering there are all kinds of related vulnerabilities. Server software such as Apache is made to be secure: it has to worry about sending arbitrary commands to bash, so why not worry about setting arbitrary environment variables too?

Comment: Re:Wrong interpretation of energy (Score 1) 135 135

by Attila the Bun (#46912055) Attached to: Is There a Limit To a Laser's Energy?

When the article is talking about 1 MeV, it falsely interprets this as if the laser is emitting a single photon at 1 MeV. That is not what happen

He is indeed talking about 1 MeV per photon. He's discussing the theoretical limits of photon power density in a hypothetical gamma-ray laser with an adjustable wavelength. An ordinary laser pointer stores more than 1 MeV of energy in its lasing cavity, although a physicist would not typically use eV to describe the combined energy of a light beam.

Comment: Re:If you want to hoard bits... (Score 1) 983 983

by Attila the Bun (#46463631) Attached to: How Do You Backup 20TB of Data?
That's what I thought. I have a backup server in the basement, built out of two Raspberry Pis attached to four USB disk enclosures. Goodsync takes about 15 minutes to scan my 4TB of data, depending on how many new files there are. It would be faster over a wired network. Scaling that up to 20TB across five 4TB drives doesn't sound expensive or difficult.

Comment: Re:Paralysis by Analysis (Score 1) 247 247

by Attila the Bun (#46352703) Attached to: The Rescue Plan That Could Have Saved Space Shuttle <em>Columbia</em>

This is exactly wrong. Putting more "human" decision makers in place is exactly what lead to the Challenger disaster and Columbia disasters.

Right. Certain people claimed that they "felt" that the weather was too cold on the day of the Challenger explosion. Others "felt" that the risk was one in a million. Who's right? If you scrub the launch whenever one of the thousands of NASA technicians feels nervous you'll never do anything. Only by quantifying the risk can you work out what to do, and it took Feynamn to demonstrate that.

Comment: Re:Here's some more stupid interview questions (Score 1) 692 692

by Attila the Bun (#46018953) Attached to: Blowing Up a Pointless Job Interview

Maybe they are clumsy questions -- I don't know the context. The question about boats may be following on from a comment about hobbies, or a desperate attempt to get a reticent candidate to open up. The question about luck may be triggered by something the candidate said which made the interviewer think they might be a chancer or risk-taker. Clumsy or not, the questions are neither rude nor inappropriate.

If somebody sneers at me every time my English dips below Shakespearean standard, I know we're not going to be working together.

Gravity brings me down.

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