Talk:Farmer in the Sky

message: Moved this from the article. 
:First appearance of the remains of a lost (but advanced) civilization.
::It needs to be clarified if this is the first appearance in Heinlein's novels. Otherwise, I would have to say that C.S. Lewis at least toyed with the idea in Out of the Silent Planet, the first volume of his "Ransom trilogy". 209.149.235.254 23:48, 8 Mar 2004 (UTC)
replies: text: It is not the first appearance in Heinlein's novels. There is a lost Selenite civilization in Rocket Ship Galileo.  There is a first in this novel, I think: the first time Heinlein appears to play with the idea of hitting the speed of light (later developed into a system of travel in Starman Jones).  Question: Should this be mentioned in the article?  It's just a glimmering thought in this novel and has absolutely nothing to do with the story. Zaslav 06:10, 19 December 2005 (UTC)
thread_title:  First Appearances 

message: I am removing the sentence that ClarityFiend added in an unsummarized, unexplained edit saying that matter conversion violates conservation laws of physics.  It does not.  Rather, it takes enormous amounts of energy. Hu 13:43, 22 October 2006 (UTC)
replies: text: That's still not quite accurate. There's no reason that matter conversion would require tremendous energy to accomplish (an atomic bomb expels far, far more energy than is used to set it off, though it's only a tiny amount of matter conversion); the only thing known for sure about matter conversion is that it releases tremendous energy, consistent with E=mc^2. grendel|khan 15:03, 22 October 2006 (UTC)
replies: text: Good point, but not always the case.  Moving towards iron-26, from either end of the periodic table, releases energy in general, but going the other way, outward from iron, requires energy.  And additional energy may be required in some reactions because of isotope considerations; i.e. it may require extra energy to boost the mass so that a decay can eject an alpha particle.  Much depends on the specific reactions and on the materials at hand.  In any case, massive amounts of energy are needed to ignite fusion reactions, regardless of net energy gain or loss. Hu 15:25, 22 October 2006 (UTC)
replies: text: Since Heinlein's mass [to energy] conversion is neither fission nor fusion, we can't say whether it requires a massive amount of energy to jump start the process. Maybe if you tickle an atom just right, it'll freely turn itself into a litter of photons (and maybe some subatomic particles, to preserve baryon number and so forth).—wwoods 22:54, 5 November 2006 (UTC)
replies: text: As far as we know now, fission and fusion are the only methods of releasing large amounts of energy from nuclear reactions. However, this book and others are science fiction, which someone seems to have lost sight of. In science fiction, we can imagine that there exist efficient methods of creating or finding antimatter, for example, as is done in Star Trek (w/o explanation). Then, you could have a "total conversion" (TC) procession of matter-antimatter annihilation, releasing energy via E=mc^2. Also, in some of the works of Isaac Asimov and James P. Hogan, "TC" processes of unknown nature are mentioned. In some of Hogan's novels, a "TC" bomb far more powerful than an H-bomb is mentioned. It is all purely S.F. so far. 74.249.79.103 (talk) 22:38, 28 September 2008 (UTC)
thread_title:  Matter Conversion