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Comment This is not a new idea. (Score 2) 381

A friend of my in the 70's who was a math grad student at the time was playing with taking the absolute value of gamma = 1 / sqrt(1-v^2/c^2) to avoid the imaginary aspect of the term. Only at light speed was a massive particle forbidden. The square of the momentum remains real. Other results were the same: Things become less energetic the farther you get from light speed in either direction. At sqrt(2) times c, your relativistic mass and time are the same as at rest and your subjective trip time matches that of distant observers. Finally, at infinite speed you have zero mass and your subjective trip time is the same as the distance traveled (times c, of course). I seriously doubt my friend was the first person to come up with this. What's different with the new publication, AFAICT, is that these guys have an eager university press office. I love it when the press release folks feel obliged to mention that the work appears in a "prestigious" journal.

Comment Higgs Boson mass vs. Top Quark Mass (Score 2) 170

I'm curious what's going on such that the top is heavier than the Higgs rather than the other way around. All I've been able to find is people asking why the top was found first. *That* I understand--the Higgs signal is much much smaller. I remember something from long ago about the top's mass "leaking," if you will, to the the lighter particles, but that doesn't mesh with how I understand the Higgs mechanism. Anyway, I would expect the Higgs particle manifestation to be the most massive of those that participate in the Higgs field.
Christmas Cheer

North Korea Threatens South Korea Over Christmas Lights 441

K7DAN writes "North Korea warned South Korea on Sunday of 'unexpected consequences' if Seoul displays Christmas lights near the tense border, and vowed to retaliate for what it called 'psychological warfare.' From the article: 'The tree-shaped, 30 metre-high steel structure on Aegibong hill - some 3km (2 miles) from the border - was illuminated by thousands of small light bulbs last year. It could be seen from the North's major city of Kaesong across the border, according to media reports. Pyongyang has previously accused Seoul of using the tree to spread the Christian message to people inside the secular state.'"

Comment Bricked by battery firmware update. (Score 1) 715

I bought a new battery for my Vaio laptop. Since it wasn't the exact same model (A/B instead of A in the part number suffix), a BIOS upgrade was necessary. The instructions included the appropriate warnings about not turning off the computer until completion. It got to what it said was part way through its verification phase and hung...and hung and hung. Even the power button stopped working. I was lucky that someone had the same model in the shop so I was able to get my data off the internal RAID0 drive pair.

Comment Re:Some more thoughts on the subject (Score 1) 388

As for the first point, we're *almost* able to detect life on extrasolar planets. All we need are spectra that show a lot of Oxygen or other gasses that don't appear in quantity without something like life to maintain them in quantities that are out of equilibrium with respect to geological processes.

I totally agree with the SETI signals point. The only thing we'd be able to detect would be a "We're Here!" signal. Non-directional broadcasts are just way too expensive. It's also likely that electromagnetic communications would use some sort of spread spectrum technique to avoid difficulty with all the random absorbing material in interstellar space.

And there's cause to hide. If the Galaxy actually is crowded.

Comment Some more thoughts on the subject (Score 3, Interesting) 388

There's been a lot of argument that "close in space *and time*" is precisely the problem. In the cosmically vanishingly small time of a million years ago, we weren't very interesting. If we're still around in a million years, we probably wouldn't want to detectably approach anyone at the level that we're at now. There's also evidence that we're heading towards "going dark" as a result of using more efficient communications so there will be an inner surface to our radio sphere of influence. There may be other things to look for, like the gamma ray signature of antimatter powered interstellar vehicles. We wouldn't see anybody on a ballistic trajectory. I'm rather taken by arguments that suggest that really advanced cultures won't want to be very spread out because of communications latency. See, for instance, this by Cirkovic and Bradbury.

As already mentioned, there is the possibility that we're the first [in our light cone].

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