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In charts of ρ distribution, such as the z = 0 image

http://www.mpa-garching.mpg.de/galform/virgo/millennium/seqF_063a_half.jpg

(taken from http://www.mpa-garching.mpg.de/galform/virgo/millennium/ ),

the distance scale is usually expressed in units of Mpc/h. In this image, there is a scale of 31.25 Mpc/h, although I think this is a misnomer-- it should be written [31.25/h] Mpc, because h isdecreasing. At present, that scale then represents 31.25/0.71= 44 Mpc. Does that seem correct?

There may be another problem; I expect the distances to scale with the scale factor "a", not with h ([itex]\propto[/itex] [itex]\dot{a}[/itex]/a). For example, from 1 Gyr to the present, h has changed by ratio ~9, whereas a has changed by ratio ~6.5, and I would think that the scale in the t = 1 Gyr image

http://www.mpa-garching.mpg.de/galform/virgo/millennium/seqF_019a_half.jpg

should represent 1/6.5 (not 1/9) of the scale in the z = 0 image. Does this seem correct?

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# Problem interpreting Mpc/h in maps of DM

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