Why is the DM density near the sun so small?

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The discussion centers on the surprisingly low dark matter (DM) density near the Sun, estimated at 0.35 × GeV/cm³ (6.2 × 10⁻²⁵ g/cm³), compared to the average DM density in the universe, which is 2.26 × 10⁻²⁴ g/cm³. This indicates that the DM density near the Sun is approximately 3.6 times lower than the universal average. Participants noted a potential confusion between units of measurement, specifically between cm³ and m³, which could lead to misinterpretation of density values. The conversation highlights the need for clarity in astrophysical measurements and encourages further inquiry into the topic.

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Buzz Bloom
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This question arose in the context of another thread.
Wikipedia gives an estimated value for the DM density near the sun of
0.35 × GeV/cm3 = 6.2 ×10−25 g/cm3.​
The value of the average DM density in the universe
ρDM = 2.26 ×10−24 g/cm3.
https://en.wikipedia.org/wiki/Milky_Way - Bottom of list of Observation data​
This means that ρDM is approximately 3.6 times the density of DM near the sun.

I unsuccessfully have tried to find references that provide an answer to the question, but my skills are not up to the challenge. I am hopeful that one or more knowledgeable participants here the PFs can help me.

Regards,
Buzz
 
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The average density in the universe is 2.26*10-30 g/cm3, 4.5 orders of magnitude thinner than the local density. I guess you mixed cm3 and m3, as the number is equal to 2.26*10-24 g/m3.

http://pdg.ge.infn.it/2015/reviews/rpp2014-rev-astrophysical-constants.pdf
 
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Hi @mfb:
Thank you very much for spoting and letting me know about my careless error.

Regards,
Buzz
 

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