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In practice, well, rent the movie Das Boot, and have a good look. That's likely how you'd live on an interstellar trip.

"The boat will need more than a can of vaseline!"

"You filthy boy! You've got crabs! A whole army of them!"

I remember an SF story - maybe in one of Brian Aldiss's Galactic Empires anthologies from the 70's - where a derelict spaceship is found. It seemed wholly alien to the humans inspecting it, owing initially to its shape, devoid of any concession to aerodynamics - instead of being sleek it was just a huge collection of cubes connected by tubes. Perhaps this story inspired the design of the Borg ships? Tried to find some info on that but about all that came up was a post on Streamlined Starships, which has some info on Star Trek/Wars designs - apparently Roddenberry decreed that the Enterprise must "look powerful," thus the nacelles splayed back.

Perhaps in the Physics of Star Trek this is given more consideration. But we're still dealing with theoretical constructs for moving FTL; assuming space travel forever remains sublight why not employ a cube as a design? It would be that much simpler to construct, after all, and there would be no putative need to deal with drag at FTL. You could also spin a series of cubes connected to a central shaft for artificial gravity.

With any of these designs it seems a simple matter to maximize volume for living quarters. I doubt the stress on the frame from acceleration would be much of a factor; you could have a largely hollow cube with ample living space inside, huge empty "parks" for instance. Or a spinning O'Neill cylinder, ala Rama.

With short intersystem hops for mining etc your U Boat scenario would be more likely to take place. Indeed if we're stuck in the solar system that might be the rule. But space stations aren't committed to designs like the ISS, either. Marshall Savage's book The Millennial Project: Colonizing the Galaxy in Eight Easy Steps has a radical design for habitats in space that are simply big balloons, with walls largely composed of water, plus some transparent metal. The water blocks projectiles, radiation, etc. He postulates suits to deal with living permanently in zero G. Interesting book.

Until people are building it, I do not find this "engineering", it is more like sci-fi. Personally I don't believe that there is a single technological solution that will fix our energy problems, there has never been one and there will never be one.

I do admit its not in the immediate future, unless we get a breakthrough launch technology soon.

Those are coming. A space elevator would be nice. You've probably heard a lot about them.
http://www.physicspost.com/printpage.php?articleId =141

A less likely, but still possible concept is a mass driver:

http://en.wikipedia.org/wiki/Mass_driver

Many of the engineering problems discussed in the article are related to energy usage and the cost of miles of superconductors. In terms of energy usage, yes, there's a high investment required. However, once we develop the ability to put large payloads in space, we can begin the generation of sufficent energy to power our mass-driver slingshot.

Also, there's some really promising moderate temperature superconductor research going on right now.

*shrug*. I can dream; these are big construction projects, but then again, so where the pyramids and the great wall of china. Technology has come a long way since those days, so we should expect more out of modern day 'wonders of the world' type investments.

Here's an article I wrote a while ago after seeing script kiddies sitting in AOL chats (yes, when I was a kid in the mid 90s I sat around in AOL chats :( ) scrolling messages from their brute force password crackers. It's all about how many possible passwords there are across different lengths and criteria, and how long it would take to try them all.
The Numerics of Screen Names and Passwords

• Physics Post: In the Belly of an Angry Giant.
• On the Structure of our Universe
• The Elegant Universe

--

The article wasn't based on silicon or anyother substance, but fundimental physics.

From my understanding of the article, the limit toted by Intel is based on leakage due to quantum tunnelling over distances of 5 nanometers or less. Now, IAAP (I am a physicist), and I know that tunneling probabilities have an exponential dependence on both distance and the height of the potential barrier which is being penetrated through. This barrier height depends on the particular materials used to manufacture pn semiconductor junctions; therefore, the OP was correct in pointing out that using different materials can get around the problems which silicon will soon meet.

Allright, IAAP (I Am A Psysicist), and I think it's good two debunk a common misconception here:

Gravity waves are not the same as gravitational waves

Gravity waves are matter density waves in fluidi (fluids or gases) caused by the interaction of two forces: bouyancy and gravity. Here, bouyancy is the upward-driving force, and gravity is the downward-driving force. The essence is that these waves require a medium to propagate (e.g. air).

Gravity waves can be found in the atmosphere, e.g. clouds which form in regular bands of cloud and clear sky, where the gravity waves carry momentum and energy from the troposphere to the middle and upper atmosphere Gravity waves can also be found on the surface of fuilds: think of the waves behind a boat. A good primer on gravity waves can be found here

Gravitational waves are a whole different ballgame! These waves have got nothing to do with matter densities as they don't require a medium to progagate: it is not matter that moves, and in that respect gravitational waves are like light (which, contrary to beliefs held at the beginnning of the century, don't require a medium such as "ether"). Gravitational waves are wacves in the spacetime-metric.

So what the hell does that mean? Well, in gravity waves, there is a wave in space (and time) in which the thing that changes over space and time is the density of matter. In gravitational waves, there also is a wave in space and time, but the thing that "wiggles" is not the density of matter (or the strength of electric and magnetic fields, like in light or EM radiation in general), but the properties of the fabric of space and time itself. You can think of it as if the coordinate system itself wiggles, so to speak. This "wiggling" results in the length of the arms of e.g. the LIGO interferometer to change ever so slightly, causing a phase shift between light beams send through both arms, which can (hopefully) be detected.

In more mathematical terms, the exact properties of space and time are called the metric. In a portion of space without any matter, the metric is flat (called the Minkovski metric), which means that the usual laws of geometry apply. In any circumstances with matter (and thus gravity) present, these laws to do hold up!

What?!, I hear you think. Yes sir, you've been lied to in geometry class! However, you've been lied to only very, very slightly. Example: if you measure the radius of a sphere (say: R), you expect to find a surface area of exactly 4/3 * pi * R^3. If the earth would be a perfect sphere (which it isn't), and you would be able to measure its radius and surface very accurately, you would find that the surface area is ever so slightly smaller than expected. Or, in other words, the radius seems to be a bit too large (in the order of 3 cm or 30 cm IIRC). Read more about space time curvature here/

A primer on gravitational waves can be found here. A more detailed description here.