Exploring the Lambda Constant and the Big Bang Theory

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In summary, the lambda constant did not actually grow exponentially in the first second of the universe. The inflationary expansion and the modern accelerated expansion are two separate things, and in inflation, the scale factor, not the energy density, grows exponentially. Therefore, the lambda constant has remained constant throughout the history of the universe.
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bobsmith76
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You know how the lambda constant just grew exponentially in the first second of the universe? That was just a temporary thing right?
 
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bobsmith76 said:
You know how the lambda constant just grew exponentially in the first second of the universe? That was just a temporary thing right?

Did it though? Think about it? Seriously hasn't it always been the same in one way. :wink:

I'm not sure what you are asking though as the first second contained an awful lot of stuff including some hyperinflation supposedly and the formation of atomic particles.

Could you rephrase it so you are being specific?
 
  • #3
bobsmith76 said:
You know how the lambda constant just grew exponentially in the first second of the universe? That was just a temporary thing right?

Do you mean the inflationary epoch? Usually Lambda refers to cosmological *constant* with does not vary in time (there are various dark energy models that do vary in time, cosmological constant is only one of the many models to explain accelerated expansion in late time, i.e. now.) In the inflationary epoch, the inflation is supposedly caused by the inflaton field, which potential term is large and drives the inflation. That is different from Lambda.
 
  • #4
As yenchin says, the inflationary expansion and the accelerated expansion of the modern epoch (perhaps due to lambda) are two separate things. Still, inasmuch as you can model inflation with lambda, such a constant in the early universe still could not have grown exponentially. Inflation has a rather strict requirement that the energy density (lambda) remain approximately constant during the expansion period. Instead, it is the scale factor, a(t), that grew exponentially during inflation: a(t) \propto e^{Ht}
 
  • #5
bobsmith76 said:
You know how the lambda constant just grew exponentially in the first second of the universe? That was just a temporary thing right?

Yeah...and the Universe hasn't been the same SINCE.
 

1. What is the Lambda Constant and how does it relate to the Big Bang Theory?

The Lambda Constant, also known as the cosmological constant, is a term in Einstein's theory of general relativity that represents the energy density of the vacuum of space. In the context of the Big Bang Theory, it is used to explain the observed acceleration of the universe's expansion.

2. How is the Lambda Constant measured and what is its current value?

The Lambda Constant is measured through various cosmological observations, such as the cosmic microwave background radiation and the distribution of galaxies. The current accepted value of the Lambda Constant is approximately 0.7, indicating that the expansion of the universe is accelerating.

3. What role does the Lambda Constant play in the inflationary period of the universe?

The inflationary period refers to the rapid expansion of the universe in its early stages. The Lambda Constant is thought to have played a significant role in this expansion, driving the universe's rapid expansion during this time.

4. How does the Lambda Constant affect the fate of the universe?

The value of the Lambda Constant has a significant impact on the future of the universe. If its value is high enough, it will continue to drive the expansion of the universe and lead to a "big freeze" scenario where the universe continues to expand and cool, eventually leading to a cold and empty state. If its value is low enough, it may eventually lead to a "big crunch" scenario where the expansion of the universe slows and reverses, potentially collapsing back in on itself.

5. Is there any evidence for the existence of the Lambda Constant?

Yes, there is strong evidence for the existence of the Lambda Constant. Its effects can be seen through various cosmological observations, such as the accelerated expansion of the universe and the distribution of matter in the universe. Additionally, the Lambda Constant is a fundamental part of our current understanding of the universe and is used in various equations and models to accurately describe its behavior.

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