Discovery.com (June 11, 2009)
" 'Star Trek' makes faster-than-light travel look easy, but according to new calculations by Italian physicists, a warp drive could easily create a black hole that would incinerate any passengers on a space craft and then suck Earth into a black hole.
" 'Warp drives are so far the best case scenario to attain faster-than-light travel,' said Stefano Finazzi of Italy's International School for Advanced Studies. This paper 'makes it much harder to realize, if not almost impossible, warp drives.'
"In normal physics, nothing can move faster than the speed of light. Einstein's theory of relativity forbids it. In normal space any object approaching the speed of light will increase in mass exponentially, and require an exponential increase in the amount of power needed to propel it forward...."
A Little Simplification is a Good Thing
Anybody writing about a highly technical or specialized subject, for people who are not familiar with the subject, has to do some simplification. I'm not talking about 'dumbing down' ideas: it's a matter of using technical terms only where really necessary - and then explaining what's going on.Up to the end of the last quote, the Discovery article was doing pretty well.
The author is discussing another bit of theoretical work, based on physicist Michael Alcubierre's theoretical description of how a bubble of space-time could be moved through our space-time at any speed - below or above the speed of light. Essentially, matter inside Alcubierre's bubble would be stationary, relative to its space-time - but that space-time would be moving through ours.
Stephano Finazzi and others found that, assuming that the bubble could be created, a great deal of energy would have to be used to maintain it.
"...Eventually the energy would run out. The bubble would rupture, with catastrophic effects. Inside the bubble the temperature would rise to about 10^32 degrees Kelvin, destroying almost anything on the bubble.
"Anyone watching the ship nearby wouldn't be much better off.
" 'We know that the warp drive will be destabilized,' said Finazzi. 'But we do not know if it will in the end explode or collapse to a black hole.'..."
At this point, I think the author simplified the explanations a little too much.
"...The results make sense, at least, when creating warp drive using exotic matter in a universe where 1 plus 1 equals 2.
"In a universe where 1 plus 1 equals 3, a possibility with string theory instead of the semi classical physics used by the Italians, a stable warp drive is viable...."
"...It's about the fundamentals of the universe; do we live in a universe where 1 plus 1 equals 2 or 3? Until scientists can answer that question, there will be significant limitations on scientific models of the universe...."
One Plus One is Three? Was the Author Drinking?
I know just enough about physics and cosmology to know that phrases like "...do we live in a universe where 1 plus 1 equals 2 or 3?..." are not nonsense.But the author didn't explain how or why one plus one could equal three. That leaves me with a satisfactory 'gee whiz' feeling, but without the knowledge I'd hoped for.
As long as I'm nit-picking, one more thing:
"...The biggest sticking point to a extra dimension-based warp drive? The entire mass of Jupiter would have to be converted into pure energy to power it...."
Again, something's left out. Is that one Jupiter-mass worth of energy for an Alcubierre of any size? Or for a 'typical' size one? If the latter, what's the 'typical' size?
Deadlines and Editorial Limitations
I've written for a periodical, and have some appreciation for the sort of compromises that have to be made, to have a fixed number of words available by a certain time.With the exceptions I've mentioned, this article is relatively easy reading, and an interesting, non-technical look at part of the current state of discussions of Alcubierre's 'warp work.'
Warp Drive Impossible? Maybe Not
Given strictly what we were told in this article, I don't see that the Alcubierre bubble approach is impossible. It sounds like, if Finazzi and his colleagues are right, it would take more energy than we have available today to make the bubble, and even more energy to maintain it.And that bad things would happen if the supply of energy ran out, and the bubble were allowed to collapse.
So far, that sounds like saying that it takes fuel to get an airliner in the air, and more fuel to keep it airborne. But maybe I'm missing something.
Related post:
- "Warp Drive: Yes, it May Be Possible; But Don't Hold Your Breath"
(May 7, 2009)
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