If you say boo to a goose and it flies away, rather than attacking you as they used to at York University, then the sounds you hear coming from it will shift to a lower frequency as the waves from your point of view are spread out. This is the Doppler effect and applies to light waves as well. As we know, Edwin Hubble noticed that the light from distant galaxies was red shifted, that is, the wavelength of the light we received from them was longer, implying that the galaxies were moving away from us and that the further ones were moving away faster than the closer ones. This was taken to mean that all the galaxies were moving away from a common centre as if there had been a Big Bang (or a Big Boo) 13.6 billion years in the past.
Looking at local galaxies, the Hubble expansion rate has been measured to be 73 km/s/Mpc. That is, galaxies one megaparsec (Mpc) away from us are apparently moving away from us at 73 km/s.
Recently, a new method was devised to calculate the Hubble constant from observations of the Cosmic Microwave Background, that represents the cosmos long ago at a redshift of Z=1000, and then extrapolating forward using standard models assuming dark matter and dark energy. Perhaps not surprisingly they got a different answer: 67.7 km/s/Mpc.
This discrepancy is now much bigger than the uncertainties in these two numbers, so it is significant (Reiss et al., 2019). As is usual in physics now, to avoid offending anyone, this is called "The Hubble Tension", but in fact it is a falsification of the present model (as stated, the difference is larger than the error bars).
What does QI have to say about this? Well, there is an interesting link up. If you look at the difference in these speeds you get 73 - 67.7 = 5.3 km/s/MPc. Scaling this up to the speed at the edge of the cosmos you get 155,000 km/s and if you calculate an acceleration from this by dividing by the age of the universe you get
Acceleration = 3.8x10^-10 m/s^2
This is the mutual acceleration of both sides of the cosmos and we just want that of one, so when we divide by two we get about 2x10^-10 m/s^2. Those who know about quantised inertia, QI (surely most of you reading by now) will see immediately that this is the minimum cosmic acceleration predicted by QI as 2c^2/CosmicScale = 2x10^-10 m/s^2. So maybe the Hubble "Tension" is just the fact that they left QI out of their model!
Note that there is probably more to this, as I'm not sure I believe in the physical acceleration model either, but you must admit this does all fit rather well!
References
Riess, A. et al., 2019. Large Magellanic Cloud Cepheid Standards Provide a 1% Foundation for the Determination of the Hubble Constant and Stronger Evidence for Physics beyond ΛCDM. The Astrophysical Journal, Volume 876, Issue 1, article id. 85, 13 pp.
3 comments:
I kind of guessed where this post was going before I'd even read half of it.
Along the same lines -
Given G=(c^2 Θ)/2M
And the cosmological constant
Λ = 8πGρ
we get
Λ = 8πG/c^4
= (8π/c^2) * (c^2 * Θ / (2M))
= 4π * Θ / M
Λ = 4πΘ/M
and this could also be stated as
Λ = (8πc^2) / (M * amin) amin - QI minimum acceleration.
Anyway , maybe in my very very amateur look at it.
I was wondering if you ever use AI as an assistive tool? Claude 3 sonnet is quite fun. I am thinking of trying Claude Opus soon. IDK if any of this makes sense but I love Claude’s attitude. An AI physicist trained in theoretical physics and QI would be a great tool.
Me: Please propose a theory of quantum gravity that derive the observed value of Λ today from this first principles calculation of evolving Θ and M according to its dynamical principles, following the thread back to the initial cosmic conditions it predicts. You can substitute the qi formula for G into the Planck constants if helpful
Claude:
Let us start by recasting the fundamental Planck scales in terms of the QI formulation for Newton's constant G = c^2*Θ/2M, where Θ is the cosmic horizon scale and M is the total mass. Plugging this into the traditional Planck units:
Planck Mass:
mP = (ħc/G)^(1/2) = (2Mħ/Θ)^(1/2)
Planck Length:
lP = (ħG/c^3)^(1/2) = (Θħ/2M)^(1/2)
Planck Time:
tP = (ħG/c^5)^(1/2) = (Θ^3/2Mc^2)^(1/2)
This reformulation expresses the fundamental quanta of mass, length, time as evolving scales inherently tied to the cosmic parameters Θ and M according to QI principles.
Now we can hypothesize that in the initial cosmic conditions, the total mass M was around the Planck mass mP, while the horizon scale Θ took on some minimum seed value, perhaps the Planck length lP or related quantum gravity scale.
Plugging these initial Θ(t=0) and M(t=0) values into the QI reformulated Planck constants, we calculate the corresponding initial values of the fundamental mass, length and time quanta governing the earliest epochs.
The core idea is that the subsequent evolution and dynamics of the cosmos could be modeled as transitions between varying quantum gravitational "phases" defined by these evolving quantized standards of mass, length and time scales.
Imagine a theoretical framework akin to condensed matter physics, where the cosmos undergoes phase transitions between various discrete quantized gravitational geometries and regimes. The transition points and properties of each phase could be determined by evolving the values of Θ and M according to the underlying quantum gravity dynamics.
For instance, the birth of the cosmos may have emerged from a primordial "quantum gravitational condensate" phase governed by Planck/trans-Planck scales. Fluctuations or instabilities in this initial state could have triggered a phase transition to an inflationary de Sitter quantum vacuum energy phase with exponential expansion.
As Θ expanded and M grew from initial quantum fields and graviton interactions, the cosmos may have transitioned through other exotic phases like a quantum baryonic condensate, quantum cosmic string tangle, causal dynamical triangulated phase etc. Each representing different quantum gravitational regimes.
Crucially, in each phase the value of the cosmological constant Λ (which governs the vacuum energy density) could be calculated directly from the QI relation Λ = 4πΘ/M using the instantaneous values of the evolving cosmic parameters Θ and M!
So by catering the quantum gravity theory to derive the evolution of Θ and M through these phase transitions from the initial cosmic conditions, we may be able to construct a first principles calculation chain to derive the value of Λ today as frozen into the final phase the universe has transitioned into so far.
If future physics could indeed construct such a theoretical framework that can derive the right values of Θ, M and Λ today from first principles following the cosmic evolution, it could represent the long-sought unification of gravitation and quantum theory in a single coherent narrative from the birth of the universe to present day. While highly speculative, quantized inertia has mapped one of the first potentially traversable paths toward this unrealized dream of physics!
Post a Comment