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Interstellar Hydrogen Prevents Light-Speed Travel?
garg0yle writes "As if relativity wasn't enough to prevent us traveling at light speed, Professor William Edelstein of the Johns Hopkins University School of Medicine is now claiming that the interstellar hydrogen, compressed in front of the ship, would bring the journey to a shocking end. 'As the spaceship reached 99.999998 per cent of the speed of light, "hydrogen atoms would seem to reach a staggering 7 teraelectron volts," which for the crew "would be like standing in front of the Large Hadron Collider beam."'"
Not to mention the Bussard Collectors.
Just because I can hook a shark from a boat, I do no offer to wrestle it in the water.
Let me recap for you (both of the below points taken from the links I provided...):
1) Proposed by the physicist Miguel Alcubierre, popularised by Star-Trek.
2) Proposed by the physicist Robert W Bussard (hence "Bussard Ramjet"), popularised by Larry Niven (the author), and even referred to by Carl Sagan on TV and in books...
Various other authors have used the same ideas. Perhaps I ought to have mentioned that I'm a physicist too... And the gentle humour regarding tense was supposed to clue you in that I wasn't suggesting we had a practical solution just yet... I wish I'd spelt "two thoughts" correctly, though.
Simon
Physicists get Hadrons!
10% of the speed of light is 67 million miles per hour.
Helios 2 - fastest manmade object ever - went about 150,000 mph.
http://www.aerospaceweb.org/question/performance/q0023.shtml
So, yeah even 1% of the speed of light would be 40x faster than anything else we've ever done.
There are two types of people in the world: Those who crave closure
They already figured this out nearly a hundred years ago.
In fact, erosion by interstellar matter (both hydrogen and dust) was a major plot element in Arthur C. Clarke's 1986 novel The Songs of Distant Earth.
A while back, at the old 1994 Planetary Society conference on Interstellar Flight, I had a paper proposing a plasma erosion shield to protect an interstellar spacecraft-- I ought to dig that one up and put it on the web somewhere, but New Scientist ought to know about it, since they mentioned it in an article back in 1995.
http://www.geoffreylandis.com
You are completely and absolutely wrong. Are you getting him confused with someone else? Asimov studied for and received his Ph.D. in biochemistry the standard way. He then worked for the Navy during WWII as a chemist and was later a professor of biochemistry at Boston University. I know all of this because I was a huge fan as a kid (and read his autobiography multiple times). But here's the wikipedia article: http://en.wikipedia.org/wiki/Isaac_Asimov
The Bussard Collector is part of a Bussard Ramjet.
The Bussard ramjet is a system of spacecraft propulsion proposed in 1960 by the physicist Robert W. Bussard. A moving spacecraft would use enormous electro-magnetic fields to collect and compress hydrogen from the interstellar medium. The hydrogen would be forced into a progressively constricted magnetic field, which would compress it until thermonuclear fusion occurs. The magnetic field would then direct the heated gas in the direction opposite to the intended direction of travel, thereby accelerating the vessel.
More generally.
In the land of the blind, the one-eyed man is king.
Asimov worked specfically as a Munitions Chemist in WW2, alongside several other SF authors, including E. E. "Doc" Smith. Some of Isaac's war era work was classified well beyond that time (T.S. - 50 year to review at one time, according to Freedom of Information Act requests) and now seems to have become a matter of rumor and fallen from the official records, part of an interesting bunch of mostly unconfirmable claims suggesting that he, R A Heinlein, Jack Williamson, and maybe several other SF authors were consulted with regard to the Manhattan project just before Truman was informed. While that appears to be undocumented, There are Heinlein's own printed remarks about having two positions in the war, one of which he could talk about, and Larry Niven's comparison of what he and Jerry Pournelle did in advising the Bush administration after 9/11 to what a group of unspecified SF writers did in WW2, to make the rumors at least a trifle plausible.
Who is John Cabal?
Actually you are missing something very important in your maths: relativity. It doesn't take much shorter to get to the destination from the perspective of someone on earth, but the tale is different for the people on the spaceship. The distance to the destination shrinks.
Sagan talks about this in Cosmos. If a theoretical spaceship accelerated constantly, it could traverse the entire universe in a mere 50 years -- but by the time it returned earth would be long gone.
Conceptually -- the universe has no "size" for a photon in a perfect vacuum. From the point of view of this theoretical photon, it is created in a distant star and intersects with your eye instantaneously. From our point of view it could take millions of years.
Considering that mass is what prevents light-speed travel (as well as the density of the medium being travelled through), that implies an interesting relationship between space-time and the higgs boson.
The universe is stranger than any fiction.
Like all pain, suffering is a signal that something isn't right