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Comment: Re:Einstein replied "Check your measurements, son" (Score 1) 1088

by phizix (#37487902) Attached to: CERN Experiment Indicates Faster-Than-Light Neutrinos

It would only mean that our prior measurements of the value of c were slightly off, and we now have a better measurement.

Nope. The value of c is defined precisely as 299,792,458 m/s. The precision of light time-of-flight calculations as done by OPERA are limited by the precision of the clocks; the best atomic clocks are precise to better than 1 part in 10^15. The 60 ns difference reported by OPERA is an O(10^-6) effect and can be measured even by cheap clocks.

The difficulty in this measurement is that the clocks at CERN and the detector at Gran Sasso, a distance of over 732km, have to be synchronized at the ~10ns level. This cannot be done reliably with GPS clocks and generally is extremely difficult; it is the most likely source of error.

Comment: Re:Then get rid of.... (Score 1) 395

by phizix (#36473202) Attached to: US Senate Votes For Repeal of Ethanol Subsidies

The damned requirement for it to be in the gasoline. IT ruins gas mileage and the gas stations are NOT selling it for 5%-10% cheaper because that is what your gas mileage loss is from running E10. They sell that crap at full price because consumers are too stupid to know better. (Most people think that "premium" is a better gas! The lack of education in fuel that is used daily by the population is incredible)

I have a flex fuel car, it get's 25% less gas mileage when running on E85 but it's designed to run on the stuff. And all the stations around here selling it are price gouging it so hard that it's only 20% below the price of the E10.

This makes E85 a net loss for me to even use it. I can be with the enviro-freaks and waste 5% gas mileage by running E85 or I can run the E10 and get optimum gas mileage at the quality of fuel available and get the most Dollars per mile out of my expense. When E85 first came out it was 40% to 50% cheaper than gasoline so I was running it all the time in the flex fuel van. But in Michigan it's $3.29 a gallon while Indiana it's $2.59 a gallon (as seen this past weekend on a trip to Chicago) There is no $1.00 a gallon tax on it, IT's that Michigan only retailer of E85 is Meijer and they are price gouging it.

I'm done with Ethanol. Until they start using real sources like switchgrass that produce more of it per acre and actually try to make it a viable fuel that is not based on corn subsudies... it needs to go away...

EXCEPT: IT's a fantastic racing fuel. I have 10 friends that are in racing and all of them have modified their cars to use ethanol instead of racing gas. IT's cheaper and they are getting MORE power from it One friend has went from 12.2 on the quarter mile to 11.9 just by changing fuel. Plus they can afford to race at $3.29 a gallon instead of $6.89 a gallon.

Ethanol has a lower energy density than gasoline, but a much higher octane rating. The high octane rating allows much higher engine compression ratios resulting in better thermodynamic efficiency. This is why your racing friends see a benefit; their engines are designed for high octane fuel. Flex fuel engines are designed to tolerate the 87 octane rating fuel at the pump and have normal compression ratios. This is the problem with flex fuel; E85 results in worse performance because the engines can't take advantage of the high octane rating.

Comment: Re:Dark matter? (Score 1) 181

by phizix (#36179936) Attached to: 'Homeless' Planets May Be Common In Our Galaxy
This possibility was strongly considered in the 1990s. Such sub-luminal objects were termed MACHOS, as opposed to the other leading theory, where dark matter is composed of WIMP particles which rarely interact with ordinary matter (except gravitationally). The MACHO theories are now strongly disfavored by observations of the cosmic microwave background. The universe didn't produce enough baryons (the particles which give stars, planets, and all ordinary matter most of its mass) to account for all of the dark matter.

Comment: Re:Spam (Score 1) 211

by phizix (#35879004) Attached to: Worlds With Two Suns May Sport Black Plants
This is incorrect. Blue photons are not more useful for photosynthesis than red. The extra energy is just thermally dissipated in the plant. Plants have no real need to use extra energy anyway, since the rate limiting step of photosynthesis is carbon fixation. This is the fundamental reason why plants do not use green wavelengths. This is not to say that blue photons are not useful to the plant; they control the phototropic response (e.g. bending toward light).
Classic Games (Games)

The Best Video Games On Awful Systems 272

Posted by Soulskill
from the diamond-in-the-rough dept.
Buffalo55 writes "For the most part, classic games manage to reappear on different systems. Just look at Nintendo. The publisher has done an excellent job bringing NES, SNES, Genesis and even old school Neo Geo titles to the Wii's Virtual Console, while Microsoft's Game Room brings the best of Atari's 2600 into the living room. Of course, not every console was a success. The '90s, in particular, saw quite a few flops from companies like Panasonic, Sega and Atari. Just because a system is a failure, though, doesn't mean all of its games suck. On the contrary, most of these machines have a few gems that fell between the cracks once the console croaked." What overlooked game on a failed platform would you like to see revived?
Hardware Hacking

Grad Student Invents Cheap Laser Cutter 137

Posted by samzenpus
from the frugal-cutting dept.
An anonymous reader writes "Peter Jansen, a PhD student and member of the RepRap community, has constructed a working prototype of an inexpensive table-top laser cutter built out of old CD/DVD drives as an offshoot of his efforts to design an under $200 open-source Selective Laser Sintering (SLS) 3D printer. Where traditional laser cutters use powerful, fixed-focus beams, this new technique dynamically adjusts the focal point of the laser using a reciprocating motion similar to a reciprocating saw, allowing a far less powerful and inexpensive laser diode to be used. The technique is currently limited to cutting black materials to a depth of only a few millimeters, but should still be useful and enabling for Makers and other crafters. The end-goal is to create a hybrid inexpensive 3D printer that can be easily reconfigured for 2D laser cutting, providing powerful making tools to the desktop."
Security

A Flood of Stable Linux Kernels Released 105

Posted by timothy
from the five-is-better-than-one dept.
Julie188 writes "Greg Kroah-Hartman has released five new stable Linux kernels, correcting minor errors of their predecessors and including improvements which are unlikely to generate new errors. As so often with kernel versions in the stable series, it remains undisclosed if the new versions contain changes which fix security vulnerabilities, although the number of changes and some of the descriptions of those changes certainly suggest that all the new versions contain security fixes."

Comment: Re:Where's the applications? (Score 1) 271

by phizix (#32586620) Attached to: Fermilab Experiment Hints At Multiple Higgs Particles

As an engineer, this is the part I'm most interested in in this subject area: getting from some theorized effect in physics to being able to create and control this effect at will, and then coming up with useful applications for it. Maybe I'm missing something, but it seems like schools gloss over all this stuff; they talk about Einstein coming up with E=mc^2, briefly mention some guys working on the Manhattan Project, and boom, next thing you know there's atomic bombs exploding.

You should start by reading about this guy named Fermi.

If it wasn't for Newton, we wouldn't have to eat bruised apples.

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