Dynamics and properties of chiral cosmic strings in Minkowski space

Davis, A.C.; Kibble, T. W. B.; Pickles, M.; Steer, D. A.

doi:10.1103/physrevd.62.083516

Cited by 35 publications

(70 citation statements)

References 33 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Lightlike null currents w = 0 must be treated separately, and in this case the equations of motion are integrable [22,32,33]. For most of this analysis we shall leave L(w) arbitrary, but we exclude chiral strings w = 0 which will be considered elsewhere.…”

Section: Preliminaries: Elastic Stringsmentioning

confidence: 99%

Y-junction intercommutations of current carrying strings

et al. 2018

View full text Add to dashboard Cite

Under certain conditions the collision and intercommutation of two cosmic strings can result in the formation of a third string, with the three strings then remaining connected at Y-junctions. The kinematics and dynamics of collisions of this type have been the subject of analytical and numerical analyses in the special case in which the strings are Nambu-Goto. Cosmic strings, however, may well carry currents, in which case their dynamics is not given by the Nambu-Goto action. Our aim is to extend the kinematic analysis to more general kinds of string model. We focus in particular on the collision of strings described by conservative elastic string models, characteristic of current carrying strings, and which are expected to form in a cosmological context. As opposed to NambuGoto strings collisions, we show that in this case the collision cannot lead to the formation of a third elastic string: if dynamically such a string forms then the joining string must be described by a more general equation of state. This process will be studied numerically in a forthcoming publication.

show abstract

Section: Preliminaries: Elastic Stringsmentioning

confidence: 99%

Y-junction intercommutations of current carrying strings

et al. 2018

View full text Add to dashboard Cite

show abstract

“…Studies of chiral cosmic string loops with constant currents [8] and simple varying currents [9] have been performed. Generally, however, we expect the current to be arbitrarily varying when loops are formed by intersections involving different strings or if different segments of the loop or string were at some point in causally disconnected regions.…”

Section: Discussionmentioning

confidence: 99%

“…The constraint equations (8) and (9) as well as the argument leading to (19) and (20) are independent of the number of dimensions the vector lives in. The only thing that changes with the number of dimensions is the parametrisation of E, the rotator that takes an arbitrary oriented plane to the plane of the first two coordinates.…”

Section: Generalisation To Higher Dimensionsmentioning

confidence: 99%

“…In a recent study of the properties of chiral cosmic strings [8] it was assumed that the current is constant. The work in [9] assumed that the current takes a very simple non-constant form.…”

Section: Preliminariesmentioning

confidence: 99%

“…As a result, parametrising strings beyond the first few harmonics proves to be a difficult task. Fortunately, in that case, there exists a method to generate strings involving products of rotation matrices [7] that act on a starting unit vector so that the unit magnitude constraint is satisfied trivially.In a recent study of the properties of chiral cosmic strings [8] it was assumed that the current is constant. The work in [9] assumed that the current takes a very simple non-constant form.…”

mentioning

confidence: 99%

See 2 more Smart Citations

Chiral superconducting strings and Nambu–Goto strings in arbitrary dimensions

Siemens

Olum

2002

Journal of Mathematical Physics

View full text Add to dashboard Cite

We present general solutions to the equations of motion for a superconducting relativistic chiral string that satisfy the unit magnitude constraint in terms of products of rotations. From this result we show how to construct a general family of odd harmonic superconducting chiral loops. We further generalise the product of rotations to an arbitrary number of dimensions.PACS numbers: 11.27.+d,98.80.Cq I. PRELIMINARIESParticle physics models where symmetry breaking is involved predict, in many cases, the existence of topological defects, which are formed when the topology of the vacuum manifold of the low energy theory is non-trivial [1]. Cosmic strings, in particular, are line-like objects that are formed when the the vacuum manifold contains unshrinkable loops. For a review see [2].In [3] it was shown that cosmic strings can be superconducting. In the case when the charge carriers on the string are not coupled to a gauge field the action for the string and the current can be taken to bewhere µ is the mass per unit length of the string, γ ab is the induced metric on the string worldsheet and φ is the field of the charge carriers living on the string. These strings were shown in [4] and [5] to have solutions in the case when γ ab φ ,a φ ,b = 0 of the formfor the string position andfor the field living on the string with the constraintsandwhere u = σ − τ and v = σ + τ and σ and τ are space-like and time-like parameters respectively that parametrise the string world-sheet. These strings are called chiral because the current only moves in one direction on the string.Comparing this to the usual Nambu-Goto case one can see that f (v) acts like a fourth component of the threevector b(v), making chiral superconducting strings behave like Nambu-Goto ones with chiral excitations in an extra fifth dimension. Indeed, this property was used in [6] in an investigation of the properties of superconducting cosmic string cusps.The right-and left-moving excitations, a ′ and b ′ , on a regular Nambu-Goto string in Minkowski space-time are arbitrary functions that satisfy the unit magnitude constraint, |a ′ | = |b ′ | = 1. Expressions for these functions are often given as Fourier sums and the unit magnitude constraint generally gives a non-linear set of equations involving the vector coefficients of the Fourier expansion. As a result, parametrising strings beyond the first few harmonics proves to be a difficult task. Fortunately, in that case, there exists a method to generate strings involving products of rotation matrices [7] that act on a starting unit vector so that the unit magnitude constraint is satisfied trivially.In a recent study of the properties of chiral cosmic strings [8] it was assumed that the current is constant. The work in [9] assumed that the current takes a very simple non-constant form. As was pointed out in the latter work one could expect to have loops with varying currents if the loops are formed by intersections involving different strings or if different segments of the loop or string were at some point i...

show abstract

Stability Longevity and All That: False Vacua and Topological Defects

Yajnik

2017

Gravity and the Quantum

View full text Add to dashboard Cite

I present two interesting studies related to the role of solitons in theories with spontaneous symmetry breaking. Quantised fermions coupled to solitons are known to induce fractional fermion number. I present an example where an unstable topological solution binding a zero mode of a majorana fermion gets stabilised due to the induced fractional number. Thus neither is the cosmic string stable nor is the fermion number conserved, yet the bound state then becomes stable due to Quantum Mechanics. The other phenomenon concerns a metastable vacuum getting destabilised due to the presence of a cosmic string. This happens because the scalar field signalling spontaneous symmetry breaking acquires a vacuum expectation value approaching its true vacuum value in the core of the string. Thus the string acts like a seed nucleating the true vacuum. The instanton mediating between the false vacuum and the exit point into the true vacuum is shown to exist and graphically displayed through a numeric calculation. T. Padmanabhan has been a long time friend and was collaborator for early investigations in this direction. I review these works done subsequently with other collaborators as a felicitation to him on his sixtieth birthday.

show abstract

Dynamics and properties of chiral cosmic strings in Minkowski space

Cited by 35 publications

References 33 publications

Y-junction intercommutations of current carrying strings

Y-junction intercommutations of current carrying strings

Chiral superconducting strings and Nambu–Goto strings in arbitrary dimensions

Stability Longevity and All That: False Vacua and Topological Defects

Contact Info

Product

Resources

About