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As far as we know stars have a limited fusion cycle. Once they fuse elements up to the element iron, there is no subsequent energy that can be released through fusion, given the inherent atomic structure of the element iron.

So premise aside, my thought experiment is: if advanced beings were able to magically 'program' or 'augment' a star through some unfathomably advanced technology to skip the element iron and continue fusion, and assuming our current understanding of chemistry/physics still holds water in this scenario, what properties would the star have?

Would the ability to fuse heavier elements imply a meaningfully longer stellar life span? Would that imply that more stars would be massive enough to create super novas? Would that increase the upper threshold for heavier elements the star could create if it goes super nova? Would there be a possibility for new elements?

That is the basic question, although we could continue down this continuum and have the super smart beings account not only for iron, but any element that would interfere with fusion.

Thanks for reading.

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  • $\begingroup$ Arash, the problem with the question is made evident in the accepted answer. The fundamental problem is not with Fe, but with all elements with the binding energy equal to that of Fe or higher. Moreover if enhanced stellar life is the concern, red dwarf stars already have life-spans sometimes estimated in the ten to twenty trillion year range. $\endgroup$
    – user3652621
    Commented Feb 1, 2017 at 16:05
  • $\begingroup$ I can see where some may find it vague. By their nature, thought experiments often are. However, at the very end of the post, you will notice I did indeed invite discussion for all elements. The post title itself was not iron specific. It was simply unlimited stellar fusion. Perhaps my initial understanding of iron and its relationship to fusion was incorrect, but that should not have impacted the validity of the question itself. Let me also add that the depth and technical jargon that goes with astrophysics already act as barriers to entry to understanding the field. $\endgroup$
    – Arash Howaida
    Commented Feb 1, 2017 at 16:24
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    $\begingroup$ No comments listed why this would be off-topic. This appears to be a classic reality-check, science-ish question, with a good answer. I see no reason for it to be closed, so nominating for re-opening. $\endgroup$
    – kingledion
    Commented Mar 13, 2017 at 13:01
  • $\begingroup$ I agree with @kingledion. $\endgroup$
    – SRM
    Commented Mar 13, 2017 at 14:46
  • $\begingroup$ Agreed, this seems plenty on-topic to me. $\endgroup$
    – James
    Commented Mar 13, 2017 at 17:04

2 Answers 2

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No. Look at a graph of binding energy and it makes an arch, with iron at the top.

All elements higher than iron will consume energy to produce, not release it.

Graph

(From hyperphysics)

Ideas to look into in order to get more energy from a white dwarf than its residual heat is providing (they take billions of years to cool down to a black dwarf):

  • strange matter. Strangelets might be more stable than normal atomic nuclei under the pressure found inside a white dwarf. Catylizing the production of strange atoms could be a literal answer in the spirit of the question posed.
  • gravity. Start collapsing the material into a black hole. This can release close to the entire rest mass in energy, and is far more than you got with fusion. Charles Stross called this a necro star.
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    $\begingroup$ Oh, well, that was a brief thought experiment haha. Thank you for helping me understand more about binding energy. $\endgroup$
    – Arash Howaida
    Commented Feb 1, 2017 at 7:56
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    $\begingroup$ This is how radiation (plutonium etc) works. Elements heavier than iron split and release energy to move towards iron. Elements lighter than iron can be fused together to release energy to move towards iron. $\endgroup$
    – Tim B
    Commented Feb 1, 2017 at 12:06
  • $\begingroup$ Straight to the point, and even with references. I like it! $\endgroup$
    – katzenhut
    Commented Feb 1, 2017 at 15:00
  • $\begingroup$ Excellent, I just noticed this has been re-opened. I thought I followed the guidelines somewhat well. Strange atoms and necro star are perfect for my advancing story. Thanks for the tweaks $\endgroup$
    – Arash Howaida
    Commented Mar 26, 2017 at 10:41
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That is a slick graph JDlugosz posted. I am intrigued to see that the binding energy is on the way back down. Since their tech is "unfathomably advanced" you could propose that they have hopped all the way up to the high atomic weight "island of stability" where they can start getting a return on their fusion. https://en.wikipedia.org/wiki/Island_of_stability

That trend line should cross back into the yield area by 300. Plus the prospect of stable superheavy elements is cool.

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    $\begingroup$ I don't think it works like that though. The island of stability is interesting but it's expected that they would still have a half-life (of unknown duration) and experience radioactive decay. It might be a good idea to make this more clearly a separate answer to the question - at the moment it feels more like commentary on the other answer. $\endgroup$
    – Tim B
    Commented Feb 1, 2017 at 14:20
  • $\begingroup$ Oh how interesting, good article! Given what I now know of binding energy, I would have to specifically state in my story that 300+ is the atomic weight in the tech details, for their miracle atomic technology to sound convincing to readers. I wonder how a stable superheavy element fueled star would differ... The half life of unknown duration sounds like a great suspense device. Thanks for making me re think the premise! $\endgroup$
    – Arash Howaida
    Commented Feb 1, 2017 at 14:21
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    $\begingroup$ Wow. It even comes with a great short story title: "The Unknown Half-Life of Civilization" $\endgroup$
    – SRM
    Commented Feb 1, 2017 at 14:51
  • $\begingroup$ @Tim B / feels like commentary/ Then vote this baby up! Once it gets more votes than the other it will be on top, fat and sassy, just like its author. $\endgroup$
    – Willk
    Commented Feb 1, 2017 at 17:28
  • $\begingroup$ @ArashHowaida Try “strangelets”. $\endgroup$
    – JDługosz
    Commented Feb 1, 2017 at 19:25

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