No quantum fluctuations found

[Alan Grayson]

https://www.sciencealert.com/a-new-measurement-of-quantum-space-time-has-found-nothing-going-on

[Alan Grayson]

Doesn't the BB depend on the existence of quantum fluctuations? If they don't exist, is the BB in trouble? AG

On Wednesday, February 17, 2021 at 2:33:23 AM UTC-7 Alan Grayson wrote:

https://www.sciencealert.com/a-new-measurement-of-quantum-space-time-has-found-nothing-going-on

[Alan Grayson]

I meant, that the BB's expansion in some versions depends on quantum fluctuations. If they don't exist, which seems to be the case, how is the physical expansion (established by empirical results) accounted for? AG

[Lawrence Crowell]

If you measure the continuum of spacetime with an optical system that has a long baseline or low energy you will get complete smooth flatness, If you probe spacetime with extremely high energy in a Heisenberg microscope setting you will get wild tumble of fluctuations and foam.

LC

On Wednesday, February 17, 2021 at 3:33:23 AM UTC-6 agrays...@gmail.com wrote:

https://www.sciencealert.com/a-new-measurement-of-quantum-space-time-has-found-nothing-going-on

[Alan Grayson]

Which measurement do you consider as representing the physical reality? And what is the role of fluctuations in the BB? TIA, AG

[John Clark]

On Fri, Feb 19, 2021 at 2:17 PM Lawrence Crowell <goldenfield...@gmail.com> wrote:

 > If you probe spacetime with extremely high energy in a Heisenberg microscope setting you will get wild tumble of fluctuations and foam.

Maybe, maybe not, 3 of the 4 forces of nature certainly fluctuate wildly when things get small but what about gravity, aka spacetime? Spacetime foam has been theorized but never actually observed because the high energy conditions needed have never been reached experimentally. Quantum Mechanics says you will see a spacetime foam If you ever make a particle accelerator powerful enough to reach the Planck level, but General Relativity says you will not. Who's right?

John K Clark   See what's on my new list at  Extropolis

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[Lawrence Crowell]

On Friday, February 19, 2021 at 1:52:50 PM UTC-6 agrays...@gmail.com wrote:

Which measurement do you consider as representing the physical reality? And what is the role of fluctuations in the BB? TIA, AG

Both, remember in a quantum and/or logic the Schrodinger cat is both alive and dead!

LC

[Lawrence Crowell]

Getting to Planck energy is of course a practical issue. This is not necessarily an issue with fundamental physics. However, in the weak field limit we have gravitational memory that is an abelian symmetry identified with I^+, in addition to the Lorentz symmetry at i^+/. Then even in a weak field limit, say the detection of gravitational waves from colliding black holes, we have find a signature of this foaminess of spacetime at much higher energy. 

LC

[John Clark]

On Sat, Feb 20, 2021 at 7:06 AM Lawrence Crowell <goldenfield...@gmail.com> wrote:

> Getting to Planck energy is of course a practical issue. This is not necessarily an issue with fundamental physics. However, in the weak field limit we have gravitational memory that is an abelian symmetry identified with I^+, in addition to the Lorentz symmetry at i^+/. Then even in a weak field limit, say the detection of gravitational waves from colliding black holes, we have find a signature of this foaminess of spacetime at much higher energy. 

But doesn't Einstein's field equation predict the existence of gravitational waves even if quantum mechanics and spacetime foam is completely ignored?  

John K Clark   See what's on my new list at  Extropolis 

.

 

[Alan Grayson]

On Saturday, February 20, 2021 at 5:01:43 AM UTC-7 Lawrence Crowell wrote:

On Friday, February 19, 2021 at 1:52:50 PM UTC-6 agrays...@gmail.com wrote:

Which measurement do you consider as representing the physical reality? And what is the role of fluctuations in the BB? TIA, AG

Both, remember in a quantum and/or logic the Schrodinger cat is both alive and dead!

LC

Maybe you can comment on the role of quantum fluctuations on the possible viability of versions of the BB theory. That is, are these fluctuations required for the expansion of the early universe? TIA, AG 

[Alan Grayson]

On Saturday, February 20, 2021 at 5:01:43 AM UTC-7 Lawrence Crowell wrote:

On Friday, February 19, 2021 at 1:52:50 PM UTC-6 agrays...@gmail.com wrote:

Which measurement do you consider as representing the physical reality? And what is the role of fluctuations in the BB? TIA, AG

Both, remember in a quantum and/or logic the Schrodinger cat is both alive and dead!

LC

IMO, as expressed repeatedly on another thread, I think this conclusion is rooted in an erroneous interpretation of the double slit experiment. The particle, localized in space, goes through ONE slit, but the deBroglie wave associated with the particle goes through BOTH slits and interferes with itself, to produce the interference pattern. Unfortunately, this is erroneously interpreted as the particle going through BOTH slits simultaneously. Schrodinger created a thought experiment to demonstrate the fallacy, but the lesson wasn't learned. AG 

[Lawrence Crowell]

Of course it does. but just as Planck showed there were some statistical rules with EM radiation and then Einstein showed the so-called Einstein coefficients with the statistics of photons, the same should hold for gravitational radiation. There should be some statistical properties underlying gravitational waves that betrays some quantum mechanical undercarriage to  GR.

LC