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Comment Re:This is what happens when you have investors (Score 1) 408

The model for investing you describe still exists. However, we now call such high risk/high reward innovation-oriented investing venture capital. It could be that the distinction you are trying to make is one of scale -- small scale investors cannot provide enough VC to get most good ideas off the ground, and as such are restricted to investing in larger, lower risk enterprises. On the other hand, it seems to me that the main change over the past fifty years on this front is the distribution of potential capital, in that many more people now invest in the stock market on a per capita basis. From that observation, I would contend that the narrowing of risk profiles is a natural consequence.

Fortunately, the actual return induced by this behavior reflects the reduced risk. See, e.g., bear.warrington.ufl.edu/ritter/PBFJ2005.pdf.

Comment Re:Magnets? (Score 2) 175

The hemoglobin in your red blood cells is reasonably paramagnetic; under the application of a large magnetic field it will produce a magnetic dipole. I suspect that the effect they are describing arises when two red blood cells get near each other. Then, the magnetic field from the induced dipole in the hemoglobin gets them to line up, much like what happens with pairs of refrigerator magnets when you bring them close. This grows into a longer and longer chain, until brownian motion overcomes the weak binding induced. The resulting chains of hemoglobin flow past each other more easily than individual particles, so long as they maintain their narrow aspect along the flow direction. The benefit claimed in the article thus pertains primarily to flow along the magnetic field's axis, where the external field keeps them oriented along its axis.

It is unclear what the metabolic effects of such chains are in practical settings--for example, how well oxygen exchange will occur with much of the cell membrane locked up against adjacent cells. Also, perpendicular flow may have a lower or higher viscosity as the unmagnetized sample (though the article is not available for reading yet, so I can only infer that it is still a bit lower due to the statements in the news release-ish article that the effect persists for some time after the magnet is turned off).

Comment Re:I'm confused. (Score 5, Interesting) 506

The key idea is that of inflation: general relativity allows for the distance between points to increase faster than the speed of light. Alan Guth's theory for inflation proposes that this in fact occured in the early universe, and the theory is now backed up by observations of fluctuations in the microwave background radiation (among others), where microscopic fluctuations were "frozen in" due to the rapid expansion. The consequence of this inflation is that much of the current universe is not within our 14 Gyr lightcone.

As a side note, the big hub-bub about dark energy is that it appears (based on current observations) that our universe may be entering a second inflationary period. Fortunately, the timescale for this is on the order 100 Gyr, so it will be unlikely to effect our lives directly.


Possible Extra-Galactic Planet Detected 83

Nancy Atkinson writes "Using a technique called pixel-lensing, a group of astronomers in Italy may have detected a planet orbiting another star. But this planet is unique among the 300-plus exoplanets discovered so far, as it and its parent star are in another galaxy. The Andromeda Galaxy, to be exact. Technically, the star in M31 was found to have a companion about 6 times the mass of Jupiter, so it could be either a brown dwarf or a planet. But either way, this is a remarkable feat, to find an object of that size in another galaxy."

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