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Cosmology is based on this idea of redshifting light, that light from very very far away is shifted toward the color red.
It turns out, that's not true. Because of how redshift is quantified there is a "divide by zero" at z=-1.
But it can't be -1
Quote from: WendelBuhbi on 11/02/2023 15:45:52But it can't be -1Of course not. Z is valid for red shifts if there isn't a red shift, don't use Z.Edit:I was not completely right on that. You can of course get a -Z, which simply means that the galaxy is moving towards you. The andromeda galaxy has a Z = -0.00042 or in other words a blue shift.
1 + z = Eemit / Eobs, z can be any positive value,But it can't be -1.
Quote from: WendelBuhbi on 11/02/2023 15:45:521 + z = Eemit / Eobs, z can be any positive value,But it can't be -1.What physical conditions would correspond to z=-1?As far as I can tell, it's the case where the light source is moving at the speed of light.Since that's impossible, it doesn't matter if the equation doesn't give a proper answer for that (non existent) case.
meaning the range of redshifts is infinite, and the range of blueshifts is finite.
Quote from: WendelBuhbi on 12/02/2023 14:36:35meaning the range of redshifts is infinite, and the range of blueshifts is finite.So, a bit like "hot" and "cold" then? You can get infinitely hot (in principle) but you can only get as cold as absolute zero.This is true, but not very exciting.
d = z c/H_0
d = -b c/H_0
1 + b = 1 / (1 + z)b = 1 / (1 + z) - 1b = 1 / (1 + z) - (1 + z) / (1 + z)b = (1 - (1 + z)) / (1 + z)b = -z / (1 + z)-b = z / (1 + z)
d = z/(1+z) * c/H_0
Im at the point where I doubt those who are not vaccinated will be missed.Also, if this is a bio-weapon, why wouldnt you get vaccinated against it?