https://matpitka.blogspot.com/2023/01/fermi-bubbles-as-expanding-magnetic.html

Monday, January 30, 2023

Fermi bubbles as expanding magnetic bubbles?

Could one apply the proposed view about structure formation based on local Big-Bangs discussed in the article Magnetic Bubbles in TGD Universe to Fermi bubbles (see this)?

Basic facts about Fermi bubbles

Consider first the basic facts.

  1. Fermi bubbles are located at the opposite sides of the galactic plane at the center of the galaxy. The radii of the bubbles are 12.5 kly and they expand at a rate of a few Mm/s (of order 10-2 c).
  2. Fermi bubbles consist of very hot gas, cosmic rays and magnetic fields. They are characterized by very bright diffuse gamma ray emissions.
  3. Quite recently, so-called eRosita bubbles were discovered (see this). They have a size scale, which is twice that for Fermi bubbles. Both Fermi bubbles, eRosita bubbles and microwave haze are believed to be associated with an emission of jets.
  4. Fermi bubbles could involve new exotic physics. The IceCube array in Antarctica (see this) has reported 10 hyper-high-energy neutrinos sourced from the bubbles with highest energies in 20-50 TeV range.
The most natural identification of Fermi bubbles is as a pair of jets emitted in the explosion associated with the galactic blackhole Sagittarius A*. According to the model discussed in the article (see this), they were born roughly 2.6 million years ago and the process lasted about 105 years.

One particular rough estimate for the release of energy from Sagittarius A* is 1050 Joules, which corresponds to 103MSun (solar mass is MSun ≈ 1030 kg). The estimate of the article for the energy would correspond to 102MSun.

Fermi bubbles as local Big-Bangs?

Could Fermi bubbles be magnetic bubbles produced by the general mechanism already discussed and perhaps even modellable as local Big Bangs?

  1. From the data summarized above, one can deduce that the mass concentrated at the bubbles is below the total energy released from Sagittarius A*. It is in the range of 102--103 solar masses. This mass need not of course correspond to mass of the Fermi sphere.
  2. The conservative option is that the expanding bubble has driven mass to the Fermi sphere as in the standard model of the Local Bubble. Recall that Local Bubble has a mass of 106 solar masses and is suggested to be caused by 15 supernova explosions emitting typically 1044 Joules: 1045 Joules corresponds to mass about 10-2MSun. For this option the mass lost by Sagittarius A* would be completely negligible with that of the Fermi bubble.
  3. The TGD inspired option is that the mass of Fermi Bubble is dark gravitational mass (102-103)MSun at the gravitational flux tubes of the dark flux tube tangles emitted by the Sagittarius A* as a pair of jets formed by the expanding Fermi spheres. These tangeles would be characterized by gravitational Planck constant.
The parameters of the local Big-Bang model of Fermi bubbles would be following.
  1. The gravitational Planck constant is partially determined by the mass of the galactic blackhole, which is about 4× 106MSun. The value of gravitational Planck constant would be huge and gravitational Compton length rS/2β0, where rS=1.2× 107 km is the Schwartschild radius.
  2. Lloc= 12.5 kly corresponds to the radius of the bubble and the length of a typical flux tube .
  3. Rloc= (3/8π GLloc)-1/4 corresponds to the thickness of the flux tubes and would be of order μm from (Lloc/Lc)1/4 scaling and Rc≈ 10-4 m.
  4. Local Hubble constant corresponds to Hloc= v/Lloc∼ 103 Hc, where v=(x/3)× 10-2c, x of order 1, is the estimate for the expansion velocity of the bubble. The TGD based model suggests that the identification β0=v/c makes sense in the beginning of the expansion. Note that for the Sun-Earth model the value of β0 is of order .5× 10-3.
Acknowledgements: I want to thank Avril Emil for interesting questions related to the notion of local Big-Bang.

See the article Magnetic Bubbles in TGD Universe: Part I or the chapter with the same title.

For a summary of earlier postings see Latest progress in TGD.

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