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Notes & Queries 9/1/07

The Sun’s evolution from protostar to stability on the main sequence, then red giant and, finally, white dwarf plays out over a bit more than twelve billion years, according to figures provided by Adam Crowl. Earth, of course, dies long before the white dwarf stage; in fact, life a mere billion years from now will be getting seriously problematic on Terra. Could future civilizations engineer a longer lifetime by controlling the Sun’s energy? This ingenious post on Crowlspace runs through the options, from inducing convection via magnetic manipulation to controlling gravitational collapse. 20 trillion years of energy hang in the balance.
“The arts and sciences are connected,” sys Ray Bradbury. “Scientists have to have a metaphor. All scientists start with imagination.” True enough, and those mind-bending tales of Martian cities and a thousand other fantastic notions never relied heavily on scientific accuracy. But they challenged us all to dream big dreams, as Bradbury has been doing since 1939 when he started a fanzine called Futuria Fantasia. With a collection of never-released novellas coming up from William Morrow, 2007 promises to be yet another vintage year. This New York Times appreciation captures the man who lives “surrounded by my metaphors.”
Brian Wang takes the Mini-Mag Orion concept studied by Dana Andrews and Roger Lenard in entirely new directions on his advanced nanotechnology site. Anxious to lose the power requirements of a massive laser array, Wang suggests deployment of a bread crumb trail of nuclear fuel pellets that would be scooped up by the nuclear rocket. Reminiscent of Jordin Kare’s fusion runway concepts (Kare called his device the ‘Bussard Buzz Bomb’), Wang’s vehicle would boost the performance of Mini-Mag Orion or even the full-blown Orion vehicle. Check out his thoughts on using Lorentz force propulsion to boost those fuel pellets!
The 36th Symposium on the Search for Extraterrestrial Intelligence meets from September 24 to 28 in Hyderabad, India, coordinated by Italian space scientist Claudio Maccone and the SETI Institute’s Seth Shostak. For more on authors and their talks check the schedule here. Sure to be interesting (and probably controversial) are presentations on active SETI strategies by Douglas Vakoch and Alexander Zaitsev.
Theoretical physicist Julius Wess, who helped to create modern ideas of supersymmetry, has died in Hamburg at the age of 72. Working with Bruno Zumino, Wess advocated a view in which fermions — familiar constituents of matter like electrons and protons — have supersymmetric partners from the realm of bosons, which carry the fundamental forces. The reverse also being true, supersymmetry theory would give us one candidate for the mysterious dark matter that seemingly fills the cosmos. The Large Hadron Collider may answer the key question of whether such ‘superpartners’ exist. Here is the New York Timesobituary.

Comments on this entry are closed.

  • Adam September 2, 2007, 2:03

    Hi Paul

    Thanks for the boost. If anyone is interested the Solar evolution sequence I use for my discussion is that of Boothroyd and Sackmann, which is available as a free download through NASA’s ADS database…


    One caveat of my idea for using gravitational collapse to power the Sun after fusion is that there’s a lot of uncertainties with the neutron star Equations of State (EsoS) so no one is too sure just how big the final collapsed state would be. Recent observation constraints are larger than many models implying a much stiffer structure than commonly assumed. If so only about a trillion years might be squeezed out of the Sun before we have to start converting it into energy directly.

    I recommend Brian’s discussion too. Using Jupiter’s magnetic field as a huge accelerator for tiny ‘starships’ is a very inventive way of cutting energy costs. His Advanced Nanotechnology blog is full of fantastic ideas and is well worth a long browse.