What Came Before the Big Bang?

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The discussion explores theories about what existed before the Big Bang, emphasizing that the Big Bang itself does not describe an infinitely dense point but rather the universe's expansion from a hot dense state. While there are speculative theories about pre-Big Bang conditions, they lack empirical evidence and remain largely untestable. The conversation highlights the challenges of studying the early universe, particularly before the epoch of recombination, where direct observations are difficult. Participants stress the importance of distinguishing between scientific theories and science fiction, noting that while some theories are well-supported, others are more speculative. Overall, the dialogue underscores the complexity and ongoing mystery surrounding the origins of the universe.
  • #31
Chronos said:
Is life after death the same as life before birth?
Heh. No. There's actual evidence of life before birth.:D
 
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  • #32
The indisputable evidence is that nothing is ever gained or lost, the sum remains the same.

I don't know of any theories which postulate that anything is created from nothing, except quantum foam, for which I believe it assumes that anything created must be consumed at some other point or "borrowed". So yes life before death should equal life after death.
 
  • #33
jerromyjon said:
The indisputable evidence is that nothing is ever gained or lost, the sum remains the same.

Tell that to the CMB...
 
  • #35
Primordial black holes form from overdensities just like galaxies, and so should appear as hot spots in the CMB.
 
  • #36
jerromyjon said:
The indisputable evidence is that nothing is ever gained or lost, the sum remains the same.
You should learn some basic cosmology before making such a statement. As drakkith pointed out, the CMB is one example of something for which this is in fact demonstrably NOT true.
 
  • #37
I'm obviously lacking in my understanding of temperature here, I'm going to do some more research and see if I can figure out what I'm missing...
 
  • #38
jerromyjon said:
I'm obviously lacking in my understanding of temperature here, I'm going to do some more research and see if I can figure out what I'm missing...

Well, one thing that you may not be aware of is that on cosmological scales, there is no such thing as conservation of energy.
 
  • #39
Closed pending moderation.
 

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