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Comment Just need repeatable results, not a theory (Score 2) 815

I call BS.

For every nickel atom converted to copper, you need about 4 additional neutrons to make stable copper (they state there is no left over radioactivity). Where are those coming from? Those are probably harder to get than shoving the single proton into the nucleus, which is hard enough!

Not plausible. But repeatable results by independent investigators is always plausible. And they don't have that either.

Comment Re:Can anybody summarize TFA? (Score 5, Informative) 184

The /. title of this article is wrong, stupid and misleading.

The title of TFA is "Dynamical mass generation via space compactification in graphene", which is mostly incomprehensible.

The abstract sez "Fermions in a graphene sheet behave like massless particles. We show that by folding the sheet into a tube they acquire non-zero effective mass as they move along the tube axis. That is, changing the space topology of graphene from 2D to 1D (space compactification) changes the 2D massless problem into an effective massive 1D problem."

A plain english annotated translation is "Electrons in a graphene sheet behave like massless particles. We show that by folding the sheet into a tube they behave like massive particles as they move along the tube axis. That is, changing the shape of graphene from 2D to 1D changes the 2D massless problem into an effective 1D massive problem, which may be easier to solve or model or understand in certain respects.

Note electrons have the same real mass in both cases. Mass is not being created or destroyed.

Comment Conservation of energy/momentum (Score 1) 221

...means the net will lose speed every time it captures some junk. The author needs to take high school physics again.

Tacking on a sailboat works because the wind is blowing on the sail, adding energy to the whole craft.

Scooping stuff in a net is just an inelastic collision. The momentum gain of the junk will equal the momentum loss of the net. The net's orbit will decay as it captures more and more junk.

Comment Re:Aliens or AI FTW. (Score 1) 903

Human level AI

I think this is unlikely without some sort of "theory of consciousness". Then again maybe we're lucky and we can build it without understanding it.

The steam engine was built without understanding thermodynamics. In fact, thermodynamics arose out of a desire to understand the steam engine.

Comment Re:L2? (Score 3, Informative) 121

Actually, it's the Earth and the Sun. It's on the Earth-Sun line, behind the earth (from the sun's point of view), and orbits the sun once a year. They put it here because it's easier to shield the satellite from both the Sun and Earth.

The L2 point for the Earth-Moon system is on the Earth-Moon line, behind the moon, and orbits the earth once evry 29.5 days.

Operating Systems

A Taste of FreeBSD With VirtualBSD 43

ReeceTarbert writes "If you wanted to try FreeBSD but didn't have the right hardware, or enough time to make it useful on the desktop, VirtualBSD might fit the bill: it's a VMware appliance based on FreeBSD 7.1-RELEASE and features the Xfce 4 Desktop Environment and a few of the most common applications to make it very functional right out of the box. If you're curious you can have a look at the screenshots, or proceed to the download page and grab the torrent file right away. (Note: VirtualBSD also works in VirtualBox 2.x as long as you create a new virtual machine and select the virtual disk from the archive instead of creating a new one)."

Comment Re:Variation (Score 1) 534

One things for sure though. I would want most systems on my ship as reliable as the Artificial gravity subsystem on Starfleet vessels. Those things can be derelict for decades, life support down, all major systems off-line, out of fuel and still the artificial gravity works flawlessly.

I know! It's as if those ships are right here on Earth!

--Gary

Networking

Submission + - NASA successfully tests DTN

hcg50a writes: NASA has successfully tested the first deep space communications network modeled on the Internet. Working as part of a NASA-wide team, engineers from NASA's Jet Propulsion Laboratory in Pasadena, Calif., used software called Disruption-Tolerant Networking, or DTN, to transmit dozens of space images to and from a NASA science spacecraft located about 20 million miles from Earth. Here's an article from July, before the test began.

Feed Science Daily: Achieving Low-carbon Growth For The World, Expert Suggests Model (sciencedaily.com)

The problem of climate change involves a fundamental failure of markets: those who damage others by emitting greenhouse gases generally do not pay. Climate change is a result of the greatest market failure the world has seen. The evidence on the seriousness of the risks from inaction or delayed action is now overwhelming. We risk damages on a scale larger than the two world wars of the last century. The problem is global and the response must be a collaboration on a global scale, according to expert.

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