Re:Some Physicists See Signs of Cosmic Strings from the Big ...
by sidcool on Tuesday September 29, 2020 @12:32PM
(#24629885)
Genuine curiousity. Do these mean strings from string theory.
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Re:Some Physicists See Signs of Cosmic Strings from the Big ...
by speakeron on Tuesday September 29, 2020 @02:11PM
(#24631103)
Imagine some water freezing. This will often start from a nucleation point and spread out rapidly. If this hits another volume of water nearby that's doing the same thing, you might get a crack in the ice where they hit each other. This is kind of what cosmic strings are. As the universe is cooling and quantum fields undergo phase changes, various regions will spread out and the point where they collide can form a cosmic string. (This is all very theoretical and my explanation is rather vague and handwavy).
Re:Some Physicists See Signs of Cosmic Strings from the Big ...
by ende on Tuesday September 29, 2020 @02:45PM
(#24631442)
Intuitive description. Thanks!
Re:Some Physicists See Signs of Cosmic Strings from the Big ...
by WORLD_ENDS_SOON on Tuesday September 29, 2020 @12:36PM
(#24629933)
From my understanding of the article, they aren't necessarily the same but could be related:
Another more speculative possibility is that cosmic strings could come from the tiny vibrating strings of string theory. Some string theory models propose that strings could have grown to colossal proportions during the initial rapid expansion of the cosmos. Differences in the tension of these kinds of cosmic strings and in how string loops break away would create a unique gravitational-wave signature distinguishing them from other kinds.
Re:Some Physicists See Signs of Cosmic Strings from the Big ...
by mhh__ on Tuesday September 29, 2020 @12:36PM
(#24629935)
https://en.wikipedia.org/wiki/Cosmic_string
Not far enough down the line to understand either theory but "string" is overloaded.
Re:Some Physicists See Signs of Cosmic Strings from the Big ...
by dfischer on Tuesday September 29, 2020 @02:40PM
(#24631383)
I'm confused, "It is expected that at least one string per Hubble volume is formed." (10^31 cubic light years.) ... one string per an observable universe?
Or am I not thinking clearly?
Re:Some Physicists See Signs of Cosmic Strings from the Big ...
by recursivecaveat on Tuesday September 29, 2020 @02:50PM
(#24631500)
The observable universe is much larger than the hubble volume. I understand this to be due to changes in the rate or expansion of the universe over time, though I'm no astronomer myself.
Re:Some Physicists See Signs of Cosmic Strings from the Big ...
by dfischer on Tuesday September 29, 2020 @04:56PM
(#24632874)
The amount of "observable universes" would be at what number given that each one is a string? How many potential strings from the initial moment? Seems... just mind boggling.