How Small Could the Universe Get in a Big Crunch?

  • Thread starter Thread starter Olias
  • Start date Start date
Olias
Messages
257
Reaction score
0
Interesting dynamical overview of 3-D >>2-D Ttransitions.

http://arxiv.org/PS_cache/hep-th/pdf/0408/0408220.pdf
 
Last edited by a moderator:
Physics news on Phys.org
I could ask Russo, given that he lives in my city, but I will save the phone call and will ask here: I'm a bit familiar with the Milne universe, actually not mainstream because cosmologists prefere general relativity, but never heard of this thing that he calls the Milne horizon. What's this?
 


The concept of a "big crunch" refers to a hypothetical scenario in which the universe, which is currently expanding, eventually stops expanding and begins to contract back towards a central point. This contraction would continue until all matter and energy in the universe is compressed into a single point, resulting in a "big crunch."

The size of a big crunch is difficult to determine because it depends on various factors, such as the amount of matter and energy in the universe and the rate of expansion. However, according to current theories, the size of a big crunch would be incredibly small, perhaps even smaller than an atom.

In the paper provided, the author discusses the interesting dynamics of a 3-dimensional universe transitioning to a 2-dimensional universe. This type of transition is known as a "dimensional reduction" and is a topic of interest in theoretical physics.

The author suggests that this transition may occur as the universe approaches a big crunch, where the extra dimensions of space become compactified and the universe becomes effectively 2-dimensional. This is an intriguing concept, as it challenges our understanding of the fundamental nature of space and time.

Overall, the idea of a big crunch and the potential for a dimensional reduction provides a fascinating perspective on the evolution of the universe. While the exact size of a big crunch may be difficult to determine, the concept itself raises thought-provoking questions about the nature of our universe.
 
Thread 'Can this experiment break Lorentz symmetry?'
1. The Big Idea: According to Einstein’s relativity, all motion is relative. You can’t tell if you’re moving at a constant velocity without looking outside. But what if there is a universal “rest frame” (like the old idea of the “ether”)? This experiment tries to find out by looking for tiny, directional differences in how objects move inside a sealed box. 2. How It Works: The Two-Stage Process Imagine a perfectly isolated spacecraft (our lab) moving through space at some unknown speed V...
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. The Relativator was sold by (as printed) Atomic Laboratories, Inc. 3086 Claremont Ave, Berkeley 5, California , which seems to be a division of Cenco Instruments (Central Scientific Company)... Source: https://www.physicsforums.com/insights/relativator-circular-slide-rule-simulated-with-desmos/ by @robphy
Does the speed of light change in a gravitational field depending on whether the direction of travel is parallel to the field, or perpendicular to the field? And is it the same in both directions at each orientation? This question could be answered experimentally to some degree of accuracy. Experiment design: Place two identical clocks A and B on the circumference of a wheel at opposite ends of the diameter of length L. The wheel is positioned upright, i.e., perpendicular to the ground...
Back
Top