Talk:Cosmic string

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diameter

In the article, it states

"Cosmic strings, if they exist, would be extremely thin with diameters on the same order as a proton."

How can a 1 dimensional object even have diameter, let alone as significant as a single particle.. the _only_ measurement would be length, right? --User:203.166.107.242

String theory says that as the strings vibrate very fast they may form loops or rings. These may be the diameters to which the article refers. -- Amaxson

I think that comment may actually be incorrect. From what I've heard, it is indeed 1 dimensional, and that would obviously violate the "order of a proton" scale. I'd be interested in knowing where that information came from, or if it's just the Wikipedia editor that tried in good will to be educative, but let that slip in the process. I listened to a lecture by Kip Thorne anyway, and he claimed that there was no diameter, due to it being a defect in spacetime. It's not something that could "contain" something. And if I'd speculate here as an amateur, I'd believe the scale, if any, would in that case be on the order of the planck length, a wildly different magnitude than that of a proton. -- Northgrove 05:43, 1 January 2007 (UTC)[reply]

The "infinitely thin" bit is just an approximation. The defect gets formed by some symmetry breaking, but that just determines the possible topologies; their thinness comes from subhorizon modes getting damped to basically nothing during radiation-dominance. -- bm

Confusion with string theory

A second piece of evidence supporting string theory is a phenomenon observed in observations of the "double quasar" called Q0957+561A,B.

Shouldn’t this read “cosmic string theory?” The issue appears to be unrelated to string theory.

Potential Update

There is a new development announced in New Scientist magazine this week, declairing that the teams findings at CSL-1 are inconclusive due to atmospheric interference. However, there is hope in that they have been granted time on the Hubble Space Telescope (they previously used the European Southern Observatory's Very Large Telescope), which should give better images and allow them to conclusivly prove that the image is a result of cosmic string refraction.

If this goes ahead, there could be a conclusive result to this question sooner than expected.

astro-ph/0601494: CSL-1 appeared to be just two similar galaxies, not a string. Should we add this?

Is this an advertisement for New Scientist? You want to add an article talking about hopes?83.103.38.68 (talk) 09:22, 19 August 2008 (UTC)[reply]

Confusing

This article is confusing. When it says "Fields", what are we as Wikipedians speaking of?

Is it Gravitational Fields or Magnetic Fields or some kind of Dark Matter - Dark Energy Field?

Perhaps it is a prairie field or baseball field. More clarity of wording would be nice.

Personally, I do not believe in this theory, but I admit I have been dead wrong before.

As far as I know, such a object cannot exist. How could it be extruded? How could it be stable?

I came here looking for an answer to my question and found no satisfactory answer.

Supercool Dude (talk) 13:50, 3 June 2009 (UTC)[reply]

Indeed, not all cosmic strings are stable, many disintegrate immediately but there are many stable configurations as well. The stability of cosmic strings in the context of string theory has been examined in http://arxiv.org/pdf/hep-th/0312067.

These objects are predicted by many theories of the early universe, including string theory and quantum field theories, and are therefore a fairly generic prediction.

User:wakabaloola 01:11, 23 August 2010 (BST)