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Old November 9th 18, 08:37 AM posted to sci.astro.research
Steve Willner
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Default Cosmological Problems

In article ,
"Richard D. Saam" writes:
What is the resolution to the Lithium problem?


Subsequent to the Big Bang, lithium is created by cosmic rays and
destroyed by stars. Are the yields known well enough to determine
the BB abundance?

No WIMPS have been found in reference to the dark matter problem.
What are the dark matter alternatives?


Massive particles that don't interact other than by gravitation (or
have extremely low cross sections) come to mind. Theorists are
creative, and no doubt there are a vast number of candidates.

Collective Effects in Nuclear Collisions: Experimental Overview
https://arxiv.org/abs/1810.06978
Viscosity plays an important role in measured LHC RHIC nuclear dynamics
Does this viscosity experimental result
influence BBN gas phased mechanisms?


Someone else will have to answer that one. Only light nuclei matter,
though.

MILKY WAY CEPHEID STANDARDS FOR MEASURING COSMIC DISTANCES AND
APPLICATION TO Gaia DR2:
IMPLICATIONS FOR THE HUBBLE CONSTANT
https://arxiv.org/abs/1804.10655
The Planck H0 = 67.4 km/s/Mpc is based on CMB.
The reported H0 = 73.24 km/s/Mpc is based on photometric parallaxes.
What mechanism explains the difference?


The difference is less than 3 sigma so may not be real. If there is
a difference, time-variable dark energy would be one possibility.
The Adam Riess colloquium I posted about earlier
https://www.youtube.com/watch?v=eSPCy-IJaPg
is still relevant and easy to follow.

The universe increased expanding rate
is an expression of dark energy measured by supernovae type II events.


I think you mean Type Ia SNe, but there are numerous other
measurements that agree.

What is dark energy?


Nobody knows, but a cosmological constant is consistent with all
data so far.

The cosmological constant problem or the vacuum catastrophe
indicates a vacuum energy theory differing from experiment
by 120 orders of magnitude.


So much for theory!

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