Bouncing universes and anti matter.

In summary, the universe has gone through several bounces and antimatter might become less after every bounce.
  • #1
wolram
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I found this article on anti matter, (far to complex for me to completely understand). what i would like to know is, does this happen at every bounce, or is this (the) start to the universe.

http://arxiv.org/PS_cache/arxiv/pdf/1007/1007.4317v2.pdf.
 
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  • #2
May be i have not worded this question in a proper way. what i want to know is , if the universe has gone through several bounces would antimatter become less after every bounce .
 
  • #3
Wolram, it's a reasonable question. I don't know the answer. But even before we can ask your question (regarding some particular bounce model), we have to ask would any matter get through a bounce----any at all?

In some particular bounce cosmology model it might be that all the usual forms of matter are destroyed and, say, only light---only very high energy photons---emerge right after the bounce.

Because newcomers might be reading this thread, we should be sure to mention that no bounce cosmo model has been proven. There is growing interest in them---they are increasingly studied---it appears possible to derive testable predictions---but the tests have not been performed (essentially because new instruments would have to placed in orbit.)

So the question being asked here is hypothetical: assuming some particular bounce cosmology is right (for definiteness say LQC) what are the first energy fields to appear after the bounce, what quantum fields besides the gravitational field itsef?

I think that is very much in the realm of "new physics". It is a fascinating question. Some people conjecture that the first offspring from the bounce would be a "scalar field" of the sort called an "inflaton". (Inflation scenarios are based on that assumption.)
You only get particles and antiparticles when the "inflaton" field decays and self-destructs, giving up its energy. No scalar field has ever been observed. AFAIK the standard model of particle physics has no place in it for such a field. The standard model would have to be enlarged, to encompass something like an "inflaton" and predict its properties.

So it's best to be humble and patient, in the face of major gaps in human knowledge like this. Try to realize how much we don't know.

But we do know that there are no "anti-photons". Or if you like, a photon of light is its own anti-particle. So that gives us a simple way of imagining the U right after the bounce. It could be nothing but expanding geometry and glorious intense light. So no antiparticles---they come a tiny fraction of a second later after the geometry has expanded some and the light has had a chance to cool down a little. This is just a simplified way of picturing---it is conjectural (so please don't hold me to it :biggrin:)
 
  • #4
Gravitons have no antiparticle equivalent, so it is difficult to construct a bounce model that works under physics as currently known. Under inflation, gravity is repulsive in the very early universe making it possible for an infinite rate of expansion for a very, very brief period of time. This would imply the universe is dead flat after inflation, which is not unreasonable given current observational data. A slight curvature remains a definite possibility and, given nature abhors infinities, suggests the early universe expanded at an enormous, albeit finite rate.
 
  • #5


I am familiar with the concept of bouncing universes and anti-matter. The article you shared explores the possibility of anti-matter being involved in the process of a bouncing universe. This is a fascinating and complex topic that is still being studied and researched by scientists.

To answer your question, it is not yet known if anti-matter plays a role in every bounce of the universe or if it is only involved in the initial start of the universe. This is an area of ongoing research and there are multiple theories and hypotheses being explored.

What we do know is that anti-matter is a fundamental aspect of our universe and is believed to be present in equal amounts to regular matter. However, it is still not fully understood why there is a noticeable absence of anti-matter in our observable universe. This is a question that scientists are actively trying to answer.

In regards to the concept of bouncing universes, it is a theoretical idea that suggests the universe goes through cycles of expansion and contraction, with each cycle being initiated by a bounce. This theory is still being explored and there is ongoing debate among scientists about its validity.

Overall, the study of bouncing universes and anti-matter is a complex and intriguing area of research that continues to push the boundaries of our understanding of the universe. I encourage you to continue learning about this topic and stay updated on new developments and discoveries in the field.
 

1. What is a bouncing universe?

A bouncing universe is a theoretical concept in cosmology where the universe undergoes a cycle of expansion and contraction, with each cycle beginning with a "bounce" or bounce back from a previous contraction. This theory suggests that our universe may have existed before the Big Bang and will continue to exist after it expands and contracts again.

2. How does anti-matter relate to the bouncing universe theory?

In the bouncing universe theory, the universe experiences cycles of expansion and contraction due to the presence of anti-matter. When matter and anti-matter collide, they annihilate each other and release energy. This energy can contribute to the expansion of the universe and eventually lead to a contraction, creating a cycle of bounces.

3. Is there evidence for a bouncing universe?

Currently, there is no conclusive evidence for a bouncing universe. This theory is still being studied and debated among scientists. Some proposed evidence includes anomalies in the cosmic microwave background and the observed distribution of matter in the universe. However, more research and observation are needed to confirm this theory.

4. What are the implications of a bouncing universe?

If the bouncing universe theory is proven to be true, it would have significant implications for our understanding of the origins and fate of the universe. It would suggest that the universe has no beginning or end and has been in an eternal cycle of expansion and contraction. It would also challenge the concept of a single event, such as the Big Bang, as the origin of the universe.

5. Can we observe a bouncing universe?

As of now, we do not have the technology or capability to directly observe a bouncing universe. However, scientists are studying various cosmic phenomena and conducting experiments to gather more evidence and potentially observe the effects of a bouncing universe. With further advancements in technology, we may one day be able to observe and understand the concept of a bouncing universe.

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