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1. • CommentRowNumber1.
   • CommentAuthorUrs
   • CommentTimeJan 22nd 2020
   • PermaLink
   Author: Urs
   Format: MarkdownItexa stub, for the moment just to satisfy links <a href="https://ncatlab.org/nlab/revision/nucleosynthesis/1">v1</a>, <a href="https://ncatlab.org/nlab/show/nucleosynthesis">current</a>

   a stub, for the moment just to satisfy links

   v1, current

2. • CommentRowNumber2.
   • CommentAuthorUrs
   • CommentTimeOct 21st 2021
   • PermaLink
   Author: Urs
   Format: MarkdownItexAdded pointer to this nice set of recent slides: * James Alvey, *What can you measure with BBN in 2021?* ([pdf](https://www.dropbox.com/s/epzydaxs6zrk9kq/BBN%20in%202021%20%282%29.pdf?dl=0), [[Alvey_BBN2021.pdf:file]]) (kindly provided [here](https://twitter.com/just_shaun/status/1450930096219430917)) <a href="https://ncatlab.org/nlab/revision/diff/nucleosynthesis/4">diff</a>, <a href="https://ncatlab.org/nlab/revision/nucleosynthesis/4">v4</a>, <a href="https://ncatlab.org/nlab/show/nucleosynthesis">current</a>

   Added pointer to this nice set of recent slides:

   • James Alvey, What can you measure with BBN in 2021? (pdf, Alvey_BBN2021.pdf:file)

   (kindly provided here)

   diff, v4, current

3. • CommentRowNumber3.
   • CommentAuthorUrs
   • CommentTimeOct 21st 2021
   • PermaLink
   Author: Urs
   Format: MarkdownItexAdded pointer to this nice set of recent slides: * [[James Alvey]], *What can you measure with BBN in 2021?*, Cosmology Talks 2021 ([pdf](https://www.dropbox.com/s/epzydaxs6zrk9kq/BBN%20in%202021%20%282%29.pdf?dl=0)) (kindly provided [here](https://twitter.com/just_shaun/status/1450930096219430917)) <a href="https://ncatlab.org/nlab/revision/diff/nucleosynthesis/4">diff</a>, <a href="https://ncatlab.org/nlab/revision/nucleosynthesis/4">v4</a>, <a href="https://ncatlab.org/nlab/show/nucleosynthesis">current</a>

   Added pointer to this nice set of recent slides:

   • James Alvey, What can you measure with BBN in 2021?, Cosmology Talks 2021 (pdf)

   (kindly provided here)

   diff, v4, current

4. • CommentRowNumber4.
   • CommentAuthorDavid_Corfield
   • CommentTimeOct 21st 2021
   • (edited Oct 21st 2021)
   • PermaLink
   Author: David_Corfield
   Format: MarkdownItexOn slide 12, how do those reactions on the left maintain equilibrium if there's no path back from p to n? So that's just beta decay? But then why (slide 13) "at about 0.28 MeV, protons can no longer be efficiently converted into neutrons" suggesting there was a p to n route?

   On slide 12, how do those reactions on the left maintain equilibrium if there’s no path back from p to n?

   So that’s just beta decay?

   But then why (slide 13) “at about 0.28 MeV, protons can no longer be efficiently converted into neutrons” suggesting there was a p to n route?

5. • CommentRowNumber5.
   • CommentAuthorDavid_Corfield
   • CommentTimeOct 21st 2021
   • PermaLink
   Author: David_Corfield
   Format: MarkdownItexEasy enough to look up. OK, so two of those paths at least are reversible [here](https://en.wikipedia.org/wiki/Big_Bang_nucleosynthesis#Neutron%E2%80%93proton_ratio).

   Easy enough to look up. OK, so two of those paths at least are reversible here.

6. • CommentRowNumber6.
   • CommentAuthorUrs
   • CommentTimeOct 21st 2021
   • PermaLink
   Author: Urs
   Format: MarkdownItexBy the way, Shaun Hotchkiss is reponsive [here](https://twitter.com/SchreiberUrs/status/1451069546131951618) and also, apparently, in contact with the author of the slides. (I should have tagged your Twitter handle, but I already had trouble meeting the character limit.)

   By the way, Shaun Hotchkiss is reponsive here and also, apparently, in contact with the author of the slides.

   (I should have tagged your Twitter handle, but I already had trouble meeting the character limit.)