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Old June 7th 20, 12:33 AM posted to sci.astro.research
Phillip Helbig (undress to reply)[_2_]
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Posts: 273
Default Is the Universe Younger than We Thought?

In article , "Richard D.
Saam" writes:

The Ho data is tightening:

**
Testing Low-Redshift Cosmic Acceleration with Large-Scale Structure
https://arxiv.org/abs/2001.11044
Seshadri Nadathur, Will J. Percival,
Florian Beutler, and Hans A. Winther
Phys. Rev. Lett. 124, 221301 - Published 2 June 2020
we measure the Hubble constant to be
Ho = 72.3 +/- 1.9 km/sec Mpc from BAO + voids
at z2

and

Ho = 69.0 +/- 1.2 km/sec Mpc from BAO
when adding Lyman alpha at BAO at z=2.34
**


I guess it depends on what you mean by "tightening". If one
measurement is X with uncertainty A, and another Z with uncertainty
C, and they are 5 sigma apart, then someone measures, say, Y with
uncertainty B, which is between the other two and compatible with
both within 3 sigma, that doesn't mean that Y is correct. Of course,
if someone does measure that, they will probably publish it, while
someone measuring something, say, 5 sigma below the lowest measurement,
or above the highest, might be less likely to do so.

It could be that Y is close to the true value, but perhaps all are
wrong, or X is closer, or Z. The problem can be resolved only if
one understands why the measurements differ by more than a reasonable
amount.