Interesting stuff with impact on the idea of space travel of any serious length beyond the moon.
First up is Technology Review’s physics arXiv blog — hyperdrive propulsion:
In 1924, the influential German mathematician David Hilbert published a paper called “The Foundations of Physics” in which he outlined an extraordinary side effect of Einstein’s theory of relativity.
Hilbert was studying the interaction between a relativistic particle moving towards or away from a stationary mass. His conclusion was that if the relativistic particle had a velocity greater than about half the speed of light, a stationary mass should repel it. At least, that’s how it would appear to a distant inertial observer.
And here’s the real fun part. Enter, Large Hadron Collider:
It turns out that when it is up and running, the LHC will accelerate particles to the kind of energies that generate this repulsive force. Felber’s idea is to set up a test mass next to the beam line and measure the forces on it as the particles whizz past.
The repulsive force the Felber predicts will be tiny but could be detected using resonant test mass. And since the experiment wouldn’t interfere with the LHC’s main business of colliding particles, it could be run in conjunction with it.
While the huge energy of the LHC make it first choice for such an experiment, Felber says the effect could also be seen at Fermilab’s Tevatron, albeit with a signal strength that would be three orders of magnitude smaller.
Next up is plasma rocket propulsion, via KurzweilAI.net:
Plasma Rocket Could Travel to Mars in 39 Days
PhysOrg.com, Oct. 6, 2009
A 10- to 20-megawatt plasma rocket could propel humanmissions to Mars in just 39 days, whereas conventional rockets would take six months or more, according to Ad Astra Rocket Company.
(Ad Astra Rocket Company)The company’s VASIMR technology uses radio waves to heat gases such as hydrogen, argon, and neon, creating hot plasma. Magnetic fields force the charged plasma out the back of the engine, producing thrust in the opposite direction. Due to the high velocity that this methodachieves, less fuel is required than in conventional engines. In addition, no physical electrodes are in contact with the plasma, prolonging the engine‘s lifetime and enabling a higher power density than in other designs.
David Kirkpatrick 