Is Hubble's constant a property of the universe, or is it the mean value of the properties of many different celestial objects? If the latter, what is the name for that property? Is it the "Hubble Value"?
By analogy, we can find the mean height of people, and say we are increasing the precision of that mean height by increasing the sample size. But we can't say we are increasing the precision of the height of people. We could also use that precision of the mean to say "The mean height of men is greater than the mean height of women" but this does not preclude individual women being taller than individual men.
On the other hand, if Hubble's constant is a fundamental property of the universe, increasing the sample size makes the measure of that constant more precise. If two different experiments lead to different measures of that same constant value, then it indicates some flaw in the experiments.
الابعاد غير معرفة فكيف يمكن ضبط القيم لهذه المتوسطات. وليس المشكل التجريب لكن ضبط المتغيرات غير ممكن بهذه الاساليب. وهناك اساليب للتنبؤ باستعمال الحوسبة باستعمل التبيان وحساب المتوسطات.
Talal Guenfoud
Thank you for your response.
Arabic: The dimensions are undefined, so how can the values for these averages be adjusted? The problem is not the experimentation, but adjusting the variables is not possible with these methods. There are methods for prediction using computation, employing representation and calculating averages.
Hubble values are generally given in km/s/MPc. This is distance/distance/time, or simply inverse time. Converted to years, 70 km/s/MPc is around 13-14 billion. The experimentation involves locating a Cepheid or Supernova in a distant galaxy, then comparing its apparent magnitude to a standard candle to estimate its distance, and comparing its spectral lines to known chemical spectral lines to estimate its velocity. Then the Hubble value is calculated from the estimated distance and estimated velocity. The quantities calculated are close to one another, but they are different for each body.
As far as how the Hubble parameter is calculated from the CMBR, though, I've seen some descriptions, but they tend to involve steps that are not fully explained.
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