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Calimero
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Are there any evidence that universe is expanding other then redshifting of EM radiation?
Tons. Here's an essay that goes into most of it:Calimero said:Are there any evidence that universe is expanding other then redshifting of EM radiation?
Redshifting is a phenomenon observed in the electromagnetic (EM) radiation emitted by distant galaxies. It refers to the stretching of the wavelength of the radiation as it travels through expanding space. This provides evidence of expansion because the greater the distance between the observer and the source of the radiation, the more redshifted the radiation appears. This is consistent with the idea that the universe is expanding, as more distant objects would have had more time to travel through expanding space.
All types of EM radiation, including visible light, radio waves, and X-rays, can exhibit redshifting. This is because all of these forms of radiation are made up of waves, and the stretching of the wavelength is what causes the redshift.
The amount of redshifting is directly proportional to the distance of the source. This means that the farther away the source is, the more redshifted the EM radiation will appear. This is a key piece of evidence for the expansion of the universe, as it supports the idea that more distant objects are moving away from us at a faster rate due to the expansion of space.
Yes, redshifting can be used to measure the expansion rate of the universe. By analyzing the amount of redshift in the EM radiation emitted by different objects at various distances, scientists can calculate the rate at which the universe is expanding. This is known as the Hubble constant, named after the astronomer Edwin Hubble who first discovered the relationship between redshifting and distance.
While redshifting is primarily seen as evidence for the expansion of the universe, there are other possible explanations. For example, the Doppler effect can also cause the wavelength of EM radiation to appear stretched as a result of the relative motion between the source and the observer. However, this explanation is not as consistent with the observed redshifts seen in distant galaxies, which is why the expansion of the universe is currently the most widely accepted explanation for redshifting.