4 ms·

This makes me wonder, if we had a significant amount of anti-hydrogen (but not enough to make a star), what would be the most complicated thing we could build o

This makes me wonder, if we had a significant amount of anti-hydrogen (but not enough to make a star), what would be the most complicated thing we could build out of it, and how would we go about doing so? (I also asked on: https://physics.stackexchange.com/questions/699258/building-things-out-of-antimatter https://physics.stackexchange.com/questions/699258/building-...)

nynx 5y ago
I’m not sure what you mean by enough to make a star. Stars don’t have antimatter in them.
- renewiltord 5y ago
  One would expect a sufficiently large amount of antihydrogen to form an antistar.
  - vba616 5y ago
    There was an old science fiction story where the first interstellar expedition discovers that the entire universe except for the solar system is antimatter. The hard way, when they try to land on an alien planet. Only it was written at some point in time between the concept being invented and the current terminology so they didn't call it antimatter. (I think it may be "Minority Report", written in 1949 by Theodore Sturgeon and not related to the Tom Cruise movie which seems to be based on a Phillip K Dick story of the same name)
- croddin 5y ago
  I just mean that most elements besides hydrogen are made in stars, theoretically with a very large amount of hydrogen you could make an antimatter star, but without doing that, what elements, molecules etc would we be able to make, if we had access to a large amount of anti-hydrogen that was contained so that it would not annihilate with our matter.
- chasil 5y ago
  Positive beta decay can and does happen, so while this assertion is correct for all intents and purposes, it is not strictly accurate. One of the potassium-40 decay paths is the emission of a positron, and this does happen in the human body. Stars with potassium-40 metalicity would see this beta decay as well. "Very rarely (0.001% of events), it decays to 40Ar by emitting a positron (β+) and a neutrino." https://en.wikipedia.org/wiki/Potassium-40 https://en.wikipedia.org/wiki/Potassium-40
amelius 5y ago
As fuel for a reactor? And just colliding it with normal matter, driving a steam engine would be enough.

nynx 5y ago

I’m not sure what you mean by enough to make a star. Stars don’t have antimatter in them.

renewiltord 5y ago
One would expect a sufficiently large amount of antihydrogen to form an antistar.
- vba616 5y ago
  There was an old science fiction story where the first interstellar expedition discovers that the entire universe except for the solar system is antimatter. The hard way, when they try to land on an alien planet. Only it was written at some point in time between the concept being invented and the current terminology so they didn't call it antimatter. (I think it may be "Minority Report", written in 1949 by Theodore Sturgeon and not related to the Tom Cruise movie which seems to be based on a Phillip K Dick story of the same name)
croddin 5y ago
I just mean that most elements besides hydrogen are made in stars, theoretically with a very large amount of hydrogen you could make an antimatter star, but without doing that, what elements, molecules etc would we be able to make, if we had access to a large amount of anti-hydrogen that was contained so that it would not annihilate with our matter.
chasil 5y ago
Positive beta decay can and does happen, so while this assertion is correct for all intents and purposes, it is not strictly accurate. One of the potassium-40 decay paths is the emission of a positron, and this does happen in the human body. Stars with potassium-40 metalicity would see this beta decay as well. "Very rarely (0.001% of events), it decays to 40Ar by emitting a positron (β+) and a neutrino." https://en.wikipedia.org/wiki/Potassium-40 https://en.wikipedia.org/wiki/Potassium-40

amelius 5y ago

As fuel for a reactor? And just colliding it with normal matter, driving a steam engine would be enough.