Quantum fluctuations = gravity?

[zaybu]

Main Question or Discussion Point

Since spacetime bubbles with quantum fluctuation energy, and energy is equivalent to mass, and mass generates gravity, wouldn't spacetime be awashed with gravity?

 

[peterfreed]

Since it is random, it creates no inhomogeneities that attract one area to another.

 

[zaybu]

Since it is random, it creates no inhomogeneities that attract one area to another.

But gravity, unlike em forces, doesn't cancel itself. It adds. So adding each point, whereby each point has energy in the form of quantum fluctuations, should give an infinite force.

 

[QuantumClue]

But gravity, unlike em forces, doesn't cancel itself. It adds. So adding each point, whereby each point has energy in the form of quantum fluctuations, should give an infinite force.

Let us say that spacetime should be awash with gravity. What would you like to observe?

Gravitons perhaps? Gravitational waves perhaps?

 

[zaybu]

Let us say that spacetime should be awash with gravity. What would you like to observe?

Gravitons perhaps? Gravitational waves perhaps?

I don't know about that, but the idea that space is filled with quantum fluctuations would lead to infinite gravity force, which is not observed. So what gives?

 

[QuantumClue]

I don't know about that, but the idea that space is filled with quantum fluctuations would lead to infinite gravity force, which is not observed. So what gives?

What if I said gravity was a psuedoforce, what would that say to you?

 

[zaybu]

What if I said gravity was a psuedoforce, what would that say to you?

Not much.

 

[QuantumClue]

And besides. Surely to have an infinite force, the universe needs to have expanded for atleast an infinite amount of time?

 

[QuantumClue]

Not much.

You don't know what you are looking for. Gravitons and gravitational waves can be thought of particles and distortions. If you don't find these, what does one look for? A psuedoforce is a bit like the corriolis force. It doesn't require a physical mediator. So when looking for gravity, there may be nothing physical to pin it to.

 

[zaybu]

And besides. Surely to have an infinite force, the universe needs to have expanded for atleast an infinite amount of time?

I don't see how you can deduce that. And I don't see how it resolves this paradox.

 

[QuantumClue]

I don't see how you can deduce that. And I don't see how it resolves this paradox.

I deduce it quite easily. But if that does not satisfy you, read above. Gravity might not even be a true physical force.

 

[sheaf]

It is an awkward problem. So much so, it has a http://en.wikipedia.org/wiki/Vacuum_catastrophe" [Broken]

 

[QuantumClue]

It is an awkward problem. So much so, it has a http://en.wikipedia.org/wiki/Vacuum_catastrophe" [Broken]

Notice the 122 magnitudes of order are not infinite.

 

[zaybu]

It is an awkward problem. So much so, it has a http://en.wikipedia.org/wiki/Vacuum_catastrophe" [Broken]

Thanks

 

[mrspeedybob]

Space extends in every direction as far as we can see. Assuming the quantum fluctuations are uniform which direction would you expect the gravity to pull you?

If they are not uniform on a very large scale then we should be accelerating towards a region of higher density, us and the rest of the observable universe with us, in which case there would still be nothing to observe.

The only senerio where there would be observable effects would be if the fluctuations were ununiform on a scale we could observe. Very unlikely.

 

[zaybu]

Space extends in every direction as far as we can see. Assuming the quantum fluctuations are uniform which direction would you expect the gravity to pull you?

If they are not uniform on a very large scale then we should be accelerating towards a region of higher density, us and the rest of the observable universe with us, in which case there would still be nothing to observe.

The only senerio where there would be observable effects would be if the fluctuations were ununiform on a scale we could observe. Very unlikely.

Good point.

 

[Ikoro]

I am actually working on a journal that tries to explain light not gravity as a quantum fluctuation in space. But when you work the math outwards you will se gravity as a by product if the fluctuation goes to zero...

 

[Fra]

The only senerio where there would be observable effects would be if the fluctuations were ununiform on a scale we could observe. Very unlikely.

If it's uniform it would be like an effective addition to the cosmological constant.

The observable consequences of that cosmological constant is by the expansion of the universe. Current cosmological models and observations yield a value that are 120 orders of magnitude off scale with what to expect from the naive quantum mechanical vacuum flucutations. but this was noted in a previous post alread.

This is the classical cosmological constant problem.
http://en.wikipedia.org/wiki/Cosmological_constant

/Fredrik