I Cosmic strings increasing internal energy?

AI Thread Summary
The discussion centers on the concept of cosmic strings and their internal energy in relation to the expansion of the universe. Edward Harrison's article suggests that the internal energy of a comoving volume, such as a cosmic string, increases as the universe expands, referencing work by Rees and Gott. There is confusion regarding the nature of this internal energy, specifically whether it refers to heat, radiation, or another form. The inquiry raises questions about whether the energy increase continues as long as the universe's expansion persists. Understanding the implications of this energy increase is crucial for cosmological theories.
Suekdccia
Messages
352
Reaction score
30
TL;DR Summary
Cosmic strings increasing internal energy as the Universe expands?
I was reading an article by Edward Harrison, which tackles the problems of conservation of energy at cosmological scales.

At some point (point 2.4) he cites several article, including one by Rees and Gott, which he says indicates that the internal energy of a comoving volume (e.g. a cosmic string) increases as the universe expands. However I have looke the article by Rees and Gott and I didn't understand it well. So, if a cosmic string increases its energy as the universe expands, will it increase as long as the expansion is maintained? And what is exactly this internal energy? Heat? Radiation?...

Link to the article: https://adsabs.harvard.edu/full/1995ApJ...446...63H
 
Space news on Phys.org
The energy is tension, if I recall.
 
Abstract The Event Horizon Telescope (EHT) has significantly advanced our ability to study black holes, achieving unprecedented spatial resolution and revealing horizon-scale structures. Notably, these observations feature a distinctive dark shadow—primarily arising from faint jet emissions—surrounded by a bright photon ring. Anticipated upgrades of the EHT promise substantial improvements in dynamic range, enabling deeper exploration of low-background regions, particularly the inner shadow...
https://en.wikipedia.org/wiki/Recombination_(cosmology) Was a matter density right after the decoupling low enough to consider the vacuum as the actual vacuum, and not the medium through which the light propagates with the speed lower than ##({\epsilon_0\mu_0})^{-1/2}##? I'm asking this in context of the calculation of the observable universe radius, where the time integral of the inverse of the scale factor is multiplied by the constant speed of light ##c##.
Title: Can something exist without a cause? If the universe has a cause, what caused that cause? Post Content: Many theories suggest that everything must have a cause, but if that's true, then what caused the first cause? Does something need a cause to exist, or is it possible for existence to be uncaused? I’m exploring this from both a scientific and philosophical perspective and would love to hear insights from physics, cosmology, and philosophy. Are there any theories that explain this?
Back
Top