There's a mystery in our universe's expansion rate and the Hubble Space Telescope is on the case

[Admin]

Scientists have a new, more accurate, measurement of the expansion of the universe thanks to observations by the Hubble Space Telescope.

There's a mystery in our universe's expansion rate and the Hubble Space Telescope is on the case : Read more

 

[rod]

What would help more I feel is a good database tracking all of the H0 values reported, like the exoplanet sites do for exoplanets. I note here some reports on H0 and the differences that keep popping up reported.

Observations of type 1a supernovae are consistent with a static universe, https://arxiv.org/abs/0901.4172, Jan-2009.
H0 = 63.1 km/s/Mpc.

NO RELEASE FOR THE HUBBLE TENSION, https://skyandtelescope.org/astronomy-news/no-release-for-the-hubble-tension/, H0 reported 73 km/s/Mpc.

Cosmological Results from the RAISIN Survey: Using Type Ia Supernovae in the Near Infrared as a Novel Path to Measure the Dark Energy Equation of State, https://arxiv.org/abs/2201.07801, H0 reported = 75.4 km/s/Mpc.

Measurements of the Hubble Constant with a Two Rung Distance Ladder: Two Out of Three Ain't Bad, https://arxiv.org/abs/2204.10866, H0 = 73.1 km/s/Mpc.

The age of the universe floats all around when you use the cosmology calculators with different H0 values and defaults. Example, using the cosmology calculator with defaults, z=0, and H0=73.1 km/s/Mpc, "It is now 13.065 Gyr since the Big Bang.", https://lambda.gsfc.nasa.gov/toolbox/calculators.html

If I setup a database and I do at home using MS ACCESS, the H0 reports I log show values ranging from 500 km/s/Mpc in the early days of study to some higher than 80 km/s/Mpc in astronomy today. Various cosmology properties like the age of the universe or size of the universe when the CMBR is postulated to first appear, bounce all over the place on the chart

 

[Catastrophe]

Obviously of great interest to many of us.

preprint version

Cat

 

[theNerdonot]

The article talks about expansion rates without mentioning time. Shouldn't 45 miles/megaparsec give an amplitude, not a rate? I am assuming it implicitly means 45 miles/second/megaparsec.

 

[Catastrophe]

The units of the Hubble "constant" are (km/sec)/Mpc,
so (miles/sec)/megaparsec is the same dimensionally.
Thus you have (length/time) / length , or reciprocal time, or T⁻¹ .
BTW, you have to watch your brackets

Cat

If anyone wants code T⁻¹ or just ⁻¹ you can cut and paste it.

Took me quite a while, but if you can use codes (I can't because my HP laptop has no NumLock key or light), then it is U + 207B.

Cat