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  #11  
Old May 21st 18, 01:50 PM posted to sci.astro.research
Phillip Helbig (undress to reply)[_2_]
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In article , jacobnavia
writes:

Le 19/05/2018 =E0 11:09, Phillip Helbig (undress to reply) a =E9crit :
Again, you are assuming a specific model, based on essentially no
information.


I am assuming that a quasar can be fed only by
1) gas
2) stars


Why this assumption?

Gas is not possible (heats up and stops the process) so it must be whole=


stars...

What else?


Primordial black holes.

You have no problem postulating that the big bang didn't happen, but are
afraid of considering primordial black holes?

Which is more probable: you assume that only stars and gas could
possibly feed a black hole, then find arguments against them---is it
more probable that this somehow concludes that something is wrong with
big-bang cosmology, or that perhaps your assumptions are wrong?
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  #12  
Old May 22nd 18, 11:10 AM posted to sci.astro.research
Phillip Helbig (undress to reply)[_2_]
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In article , jacobnavia
writes:

Le 19/05/2018 =E0 11:09, Phillip Helbig (undress to reply) a =E9crit :
The star mentioned above has oxygen, what implies at least several
generations of stars to produce it,

Why? One generation will produce oxygen.


Yes, but when the star explodes that oxygen will be enormouly diluted in
the surrounding gas...
To make an oxygen signal visible 13 Gy away the concentration of oxyygen
should be quite high.


Are you just making this up or did you get it from somewhere? Note also
that the first stars might have been VERY massive, producing
correspondingly more oxygen (no, I am not just making this up).
  #13  
Old May 23rd 18, 08:54 PM posted to sci.astro.research
Steve Willner
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Posts: 1,140
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In article ,
jacobnavia writes:
To make an oxygen signal visible 13 Gy away the concentration of oxyygen
should be quite high.


What mass of (doubly ionized) oxygen did you derive? Concentration
doesn't matter, of course, but presumably mass was what you meant.
You'll have to assume a density, but 10^3 cm^-3 would be a reasonable
guess. I'm surprised the authors didn't do this calculation, but
maybe they considered the density too speculative.

--
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Steve Willner Phone 617-495-7123
Cambridge, MA 02138 USA
  #14  
Old May 29th 18, 04:22 PM posted to sci.astro.research
jacob navia
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[[Mod. note -- I apologise for the delay in processing this article,
which was originally submitted on Thursday 2018-05-24. -- jt]]

Le 20/05/2018 √* 22:05, Jonathan Thornburg [remove -animal to reply] a
√©crit¬*:
https://arxiv.org/pdf/1805.04317.pdf

*This* paper (1805.04317) describes an object at redshift z=4.75, not
redshift z=17. (The paper does refer to "z=17", but that's a*magnitude*
(log of brightness in a certain wavelength range), not a redshift. You
can tell this because the paper says "magnitude z=17".)


Mr Thonburg is right. I have misunderstood that article.

I apologize for this error.

jacob
 




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