I The theoretical basis for a hot Big Bang?

[hkyriazi]

Is the theoretical basis for a hot Big Bang simply the combination of the assumedly redshifted CMBR (whose photons were thus thought to be much more energetic long ago), along with the assumed much tighter packing of matter in the initially much smaller space? (The perceived need for such a hot initial Universe in order for nucleosynthesis to occur is a side benefit.)

 

[Drakkith]

As opposed to a 'cold' big bang? Or no big bang at all?

 

[hkyriazi]

As opposed to a 'cold' big bang? Or no big bang at all?

The latter, and also "cold" nucleosynthesis. The redshift/distance relationship can also be explained in a much more visualizable and intuitive way as an inherent redshift of ancient matter's light emissions/absorptions, and that the latter have gradually been getting bluer since then. Also, Fritz Zwicky sought a reasonable explanation back in 1933, with his "tired light" hypothesis. But such ideas haven't been seriously pursued because they lacked a theoretical foundation.

 

[Vanadium 50]

But such ideas haven't been seriously pursued because they lacked a theoretical foundation.

No, they were abandoned because their predictions don't match observation.

As an example, "tired light" predicts more scatter than is observed. This was noticed by...um...Fritz Zwicky.

 

[Jaime Rudas]

No, they were abandoned because their predictions don't match observation.

That's right, as explained in detail here:

https://astro.ucla.edu/~wright/tiredlit.htm

 

[berkeman]

Thread closed temporarily for Moderation...

 

[PeterDonis]

the theoretical basis for a hot Big Bang

...is a lot more than what you're describing in your OP. I suggest taking some time to work through a good modern textbook on cosmology, such as Liddle:

https://www.amazon.com/dp/0470848359/?tag=pfamazon01-20

Having a good initial understanding of the model will enable you to ask much better questions.

 

[PeterDonis]

After moderator review, this thread will remain closed.