- #1

- 195

- 7

## Main Question or Discussion Point

The title says a lot about my doubt. I dont know a lot about inflation maths but the idea is that in Inflation, Im seeing that the Cosmological Constant (ie Vacuum Energy) is not Constant in two ways:

1 With time; the Vacuum Energy was larger in the beginning and that triggered Inflation. Some time later, the Vacuum Energy got smaller and then the rate of expansion got smaller too.

2 With space: The Vacuum Energy got smaller in some places first and in some others later, and that produced inhomogeneities.

But in GR the Cosmological Constant must be Constant because, if it is not constant, then the left hand of the Einstein Equation is not a Tensor (or something like that).

So, I'm seeing a trouble trying to reconcile Inflation with GR. Obviously, I must be thinking something wrong, but I cant see where! I will find your thoughts very helpful as always!!!

Thanks in advance

1 With time; the Vacuum Energy was larger in the beginning and that triggered Inflation. Some time later, the Vacuum Energy got smaller and then the rate of expansion got smaller too.

2 With space: The Vacuum Energy got smaller in some places first and in some others later, and that produced inhomogeneities.

But in GR the Cosmological Constant must be Constant because, if it is not constant, then the left hand of the Einstein Equation is not a Tensor (or something like that).

So, I'm seeing a trouble trying to reconcile Inflation with GR. Obviously, I must be thinking something wrong, but I cant see where! I will find your thoughts very helpful as always!!!

Thanks in advance