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Comment With MagLev, Tunnels not needed (Score 1) 220

Fifty years ago, Drs. Gordon T. Danby and James R. Powell of Brookhaven National Labs on Long Island, New York, invented first-generation Superconducting Magnetic Levitation (SC MagLev) Rail, using dipole magnets. This was used for the current JR Central MagLev system in Japan. Since then, they have developed their far-superior second-generation system, using quadrupole magnets. In this system, the vehicles are not so much levitated above the rail, but suspended by the sides of the rail, so that any effort to move the vehicle up, down, or to the left or right, elicits strong restoring forces, meaning it can resist all but the strongest winds. Also, since the gap between the rail and the vehicle is about 4" (10 cm), if the rail gets iced up,it is only necessary to de-ice it to a depth of about 2½" (6 cm). Thus, second-generation MagLev is almost impervious to weather. Also, this MagLev system can handle the steep grades needed when crossing a mountain. With external propulsion power, as much energy as is needed can be used to raise each vehicle over the mountain, and most all that energy would be recovered as it descends the mountain on the other side. Thus, you could have ordinary MagLev vehicles, some as small as individual passenger cars, that could cross over the mountains on open-air MagLev monorails. For details, see, with links to Danby and Powell's work in Group A (Antecedents and Allies). Tunnels are expensive and of limited capacity. MagLev rails are a lot cheaper, and just as good.

Comment Alta Vista and Bayesian "Logic" (Score 1) 172

My experience with Alta Vista was that sometimes it seemed to go "off-track", answering, not my question, but a similar question. When I tried to refine my query, it still seemed stuck on what it thought I asked before, not what I was asking.

I later found out that they used "Bayesian Logic", where the answers to the previous questions guided the answer to the new question. No wonder I had this problem!

When Google came along, of course I went with them, and still do. They are still the #1 Search Engine, although some of their other services, like Google Maps, have become untrustworthy.

Comment I would invest in perfecting MagLev (Score 1) 842

If I had a billion dollars, I would invest in perfecting Danby-Powell superconducting MagLev. See For three-quarters of that amount, a test facility could be built in Nevada (see http://www.readinessresource.n...). This would eventually lead to a nationwide MagLev net that could bring MagLev depots to within ten miles of any point in any built-up (urban or suburban) area.

In ten years, this can replace existing passenger and freight rail, and displace a lot of air travel. In forty years, this could be a multi-trillion dollar industry satisfying most of the county's transportation needs cleanly and efficiently.

Comment Momentum of tachyon traveling at infinite speed (Score 1) 142

One of the strange things about a tachyon is that it can be traveling in one direction for some real inertial reference frame, and be traveling in another direction for some other inertial reference frame. For yet another reference frame intermediate between those two, the tachyon is traveling at infinite speed, yet has zero dynamic mass and a finite momentum of +/- i mc, where i is the square root of -1, m is the imaginary rest mass of the tachyon, and c is the speed of light.

The direction of the momentum vector is ambiguous.

Since this is a total contradiction, I assume that tachyons cannot exist.

Comment I use NoScript; I also have a weak connection (Score 1) 230

I use NoScript, and only allow Javascripts that I trust.
I am also a Comcast customer. The cable connection is through an old, weak cable that goes through the apartment downstairs, and it slows down my connection a bit, but that is tolerable. To fix it, they would have to rip apart the walls in a bedroom occupied by an eight-year-old girl, and I don't want to put any child through that trauma. If I allow Comcast to share my cable connection, then I might be slowed down to an unacceptable level.
Also, their new cable modems DO NOT come with a battery backup -- they make you buy the battery from them.
They say that nobody can take advantage of you without your permission. Well, I'm paying enough in cable bills, and I'm not going to let them. Unfortunately, FiOS is not available in my apartment complex, so Comcast has a monopoly.

Comment How about a tax to support Scientific Research? (Score 1) 434

Since the internet was an outgrowth of US-government-supported research, how about a flat sales tax (say 5%) on internet sales, not otherwise subject to state sales tax, that would go to fund scientific research of all sorts, including both basic and applied research. The government can take the difference from what it now spends on research, and give it to the states to compensate for lost revenue.

This way, scientists can be assured of a consistent source of funding. This will make America smarter, and more competitive.

Submission + - Ask Slashdot: Should there be a National Tax to Subsidize Scientific Research? 3

Josh-Levin writes: "Scientific research in the US is hurting. Now there is talk of shutting the Relativistic Heavy Ion Collider (RHIC) at Brookhaven. I know that the Federal Government is short of money, but cutting back on scientific research is eating our seed corn.

Since basic research has been fundamental to all those hi-tech device we all enjoy, I think there should be a fixed Federal excise tax on hi-tech devices, the proceeds to go to scientific research. There shall be safeguards to prevent this tax money from being used for anything but scientific research.

I hope that Slashdot members who respond to this posting will flesh out this idea. How much money is needed, and how big is the hi-tech market? What should the tax rate be? (If it were 10%, it could be termed a "Techo-Tithe".) Who should be exempt? Should it be used only for terrestrial research, or should it include the space program? For products that are partially hi-tech, such as automobiles, should there be a reduced rate based on the hi-tech content of the product?

Ideally, the tax would be paid by the consumer, so that it is visible. Every time you by a computer, a smart phone, or a digital camera, you will know that your tax will subsidize the research behind the next generation of devices, which may be spintronic or optical rather than electronic.

I hope that this discussion will result in a "We the People" petition to the White House (see to ask that such a tax be implemented. We need 150 signatures to make such a petition visible, and 100,000 signatures to make sure the President sees it. Please, readers, do not initiate such a petition on your own, until the Slashdot discussion has reached some sort of consensus. We will want to do it right the first time."

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I'm always looking for a new idea that will be more productive than its cost. -- David Rockefeller