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Comment: Re:And why not? (Score 1) 185

by smaddox (#49367531) Attached to: Nation's Biggest Nuclear Firm Makes a Play For Carbon Credit Cash

Humanity's power generation is currently negligible compared to the amount of energy injected into Earth's ecosystem by the Sun. However, at current growth rates that will not hold true for long. If the current growth rate of about 2.3% is maintained (which it cannot be), then in about 400 years we will produce as much energy as falls on the Earth from the Sun. By that point in time, the surface temperatures on Earth would have raised by about 50 Celsius, making human habitation close to impossible.

Comment: Re:And why not? (Score 1) 185

by smaddox (#49367477) Attached to: Nation's Biggest Nuclear Firm Makes a Play For Carbon Credit Cash

And never mind that nuclear plants don't "blow up". Unless you fill them up with TNT and set it off, of course.

Well, that's not entirely true... Hydrogen buildup and ignition can result an explosion, which did happen at Fukushima. I don't think this is what the GP had in mind, though. Nuclear piles are designed such that criticality cannot result in a nuclear detonation (actually, it takes careful design to achieve nuclear detonation even with weapons-grade fissile material). Worst case, in older designs, is that the nuclear fuel melts through its containment vessel, resulting in a radioactive leak.

Comment: Re: How big is it? (Score 2) 37

by smaddox (#49357925) Attached to: Behind the Scenes At a Quantum Dot Factory

Short answer is no. Although there are plenty of other semiconductor devices that can operate in the microwave.

The "quantum" part of quantum dots is that the effective bandgap of the semiconductor, which controls the wavelength of luminescence, is increased by quantum confinement. Google particle in a box for more information.

Comment: Re:Most HEP and astrophysics people use Mac (sorta (Score 1) 385

by smaddox (#49288985) Attached to: Ask Slashdot: Choosing a Laptop To Support Physics Research?

How exactly is version control useful for writing documents? Backups I can understand, but version control? I'll sometimes save copies with a v1, v2, etc. appended just to have a fall-back in case something goes wrong, but I don't think I've ever actually needed to go back to a previous version.

Comment: Re:As a PhD in particle physics... (Score 1) 385

by smaddox (#49288949) Attached to: Ask Slashdot: Choosing a Laptop To Support Physics Research?

+1 Python. Write first, optimize later (if at all) using Cython or separate C packages. I'm also keeping an eye on the Nim language; it's still too buggy for real use, though.

I used to use the Enthought python distribution, but it's become too complicated. I've now moved to compiling and installing python through homebrew on my Mac, and then installing the python packages from the pypi repository. I highly recommend using homebrew for anything you want to run from the command line.

For Windows boxes, I've been installing Anaconda Python.

As for IDE, I've been very happy with the eclipse-based Aptana Studio 3, with pydev. I still use VIM for small scripts, but the features provided by pydev, such as refactoring, are very handy for larger projects.

Comment: Re:Why Choose? Run linux on a mac (Score 3, Informative) 385

by smaddox (#49288881) Attached to: Ask Slashdot: Choosing a Laptop To Support Physics Research?

I second choosing Mac. The relatively new package manager, Homebrew, is a dream come true. It makes compiling, installing, and managing open source software a breeze (easier than most linux distributions). I very rarely need to use linux any more, but interacting with it over the network is easy through ssh, etc.

There was a 1-2 week learning curve coming from Windows/Linux, but it was well worth it.

Comment: Re:VR Demands Specialized Input Devices (Score 1) 124

by smaddox (#49268779) Attached to: Valve's SteamVR: Solves Big Problems, Raises Bigger Questions

Short-term though, you're going to fuck up your eyes using any first-gen consumer VR for 8-10 hrs per day (a la any work situation), and it'll be cheaper/more expedient to just buy an extra monitor.

You're eyes are focused at infinity with this gen. of VR, so no eye strain. It's unclear if there will be any long-term physiological affects, though. Eventually, retinal displays will have shifting focus based on the in-world content.

Comment: Re:Energy costs of transport (Score 1) 91

by smaddox (#49236831) Attached to: Dry-Ice Heat Engines For Martian Colonists

At worst, it would thicken the martian atmosphere.

In practice, it wouldnt do anything at all. Mars is already at thermal equalibrium [sic], and the only energy source is sunlight. The ice is frozen atmospheric gas! The lower sunlight delivered to the poles causes it to freeze out there. This is a renewable energy resource.

I think you mean thermal steady state. A body at 140-300 K being illuminated by a ~6000 K blackbody radiation source is far from equilibrium.

Also, shipping dry ice around is probably overkill. The difference between night-time and day-time surface temperatures on Mars can be as high as ~150 K, and the low night-time surface temperatures means high Carnot efficiencies are possible (eta = 1 - T_C/T_H ~= 1 - 150/300 ~= 50%). The possibility of cheaply exploiting that difference in large heat engines could make it economical compared to photovoltaics. It might even be possible to combine the two in the same system, with waste heat from the photovoltaic cells going in to the heat engine.

Comment: Re:Stomp Feet (Score 4, Informative) 391

by smaddox (#49152529) Attached to: Verizon Posts Message In Morse Code To Mock FCC's Net Neutrality Ruling

(the oft discussed "fast lane" has yet to actually happen)

I get about 5x lower bandwidth streaming movies from Amazon than from Netflix. I've stopped renting HD movies from Amazon because the buffering kills it. Netflix happens to have paid to AT&T (my ISP) to get preferred service [1].

Hmm... That sounds an awful lot like a "fast lane" to me.


A language that doesn't affect the way you think about programming is not worth knowing.