Structure of axionic domain walls

Huang, Ming Chih; Sikivie, P.

doi:10.1103/physrevd.32.1560

Cited by 97 publications

(109 citation statements)

References 31 publications

Supporting

Mentioning

107

Contrasting

Order By: Relevance

“…The surface mass density of the wall is also estimated as σ = 8mη 2 /N 2 DW if we use this exact solution. However, if we include the structure of the neutral pion field which varies inside the wall, the surface energy density of the wall becomes a slightly larger value [34] …”

Section: Dynamics Of Domain Wall Network With Multiple Vacuamentioning

confidence: 99%

Evolution of string-wall networks and axionic domain wall problem

Hiramatsu¹,

Kawasaki²,

Saikawa³

2011

J. Cosmol. Astropart. Phys.

View full text Add to dashboard Cite

We study the cosmological evolution of domain walls bounded by strings which arise naturally in axion models. If we introduce a bias in the potential, walls become metastable and finally disappear. We perform two dimensional lattice simulations of domain wall networks and estimate the decay rate of domain walls. By using the numerical results, we give a constraint for the bias parameter and the Peccei-Quinn scale. We also discuss the possibility to probe axion models by direct detection of gravitational waves produced by domain walls.

show abstract

Section: Dynamics Of Domain Wall Network With Multiple Vacuamentioning

confidence: 99%

Evolution of string-wall networks and axionic domain wall problem

Hiramatsu¹,

Kawasaki²,

Saikawa³

2011

J. Cosmol. Astropart. Phys.

View full text Add to dashboard Cite

show abstract

“…The later, however, slightly depends on the axion model which can change Eq. (6) by a factor of the order of one [17]. Under the influence of surface tension an initially static bubble collapses to its center which yields reduction of the surface energy.…”

Section: Axion Bubblesmentioning

confidence: 99%

Oscillating axion bubbles as an alternative to supermassive black holes at galactic centers

Svidzinsky¹

2007

J. Cosmol. Astropart. Phys.

View full text Add to dashboard Cite

Recent observations of near-infrared and X-ray flares from Sagittarius A * , which is believed to be a supermassive black hole at the Galactic center, show that the source exhibits about 20-minute periodic variability. Here we provide arguments based on a quantitative analysis that supermassive objects at galactic centers may be bubbles of dark matter axions rather than black holes. An oscillating axion bubble can explain periodic variability of Sagittarius A * and yields the axion mass about 0.6 meV which fits in the open axion mass window. The bubble scenario with no other free parameters explains lack of supermassive "black holes" with mass M < 10 6 M⊙. Low-mass bubbles decay fast and as a result are very rare. We also found that the mass of an axion bubble can not exceed 1.5 × 10 9 M⊙, in agreement with the upper limit on the supermassive "black hole" mass obtained from observations. Our finding, if confirmed, suggests that Einstein general relativity is invalid for strong gravity and the gravitational field for the bubble effectively becomes repulsive at large potential. Imaging a shadow of the "black hole" at the Galactic center with VLBI in the next decade can distinguish between the black hole and the oscillating axion bubble scenarios. In the case of axion bubble, a steady shadow will not be observed. Instead, the shadow will appear and disappear periodically with a period of about 20 min.

show abstract

“…The key players in our mechanism are domain walls formed at the QCD phase transition that possess an internal structure of QCD scale. We shall present a full exposition of these walls in [6] but to be concrete, we shall discuss an axion wall similar to that described by Huang and Sikivie [8].…”

Section: −2mentioning

confidence: 99%

Primordial Galactic Magnetic Fields from Domain Walls at the QCD Phase Transition

Forbes

Zhitnitsky

2000

Phys. Rev. Lett.

View full text Add to dashboard Cite

We propose a mechanism to generate large-scale magnetic fields with correlation lengths of 100 kpc. Domain walls with QCD-scale internal structure form and coalesce obtaining Hubble-scale correlations while aligning nucleon spins. Because of strong CP violation, the walls are ferromagnetic, which induces electromagnetic fields with Hubble size correlations. The CP violation also induces a maximal helicity (Chern-Simons) which supports an inverse cascade, allowing the initial correlations to grow to 100 kpc today. We estimate the generated electromagnetic fields in terms of the QCD parameters and discuss the effects of the resulting fields.

show abstract

Structure of axionic domain walls

Cited by 97 publications

References 31 publications

Evolution of string-wall networks and axionic domain wall problem

Evolution of string-wall networks and axionic domain wall problem

Oscillating axion bubbles as an alternative to supermassive black holes at galactic centers

Primordial Galactic Magnetic Fields from Domain Walls at the QCD Phase Transition

Contact Info

Product

Resources

About