Gravitational force of antimatter

[JamesOrland]

According to the eternal inflation models, there is no t = 0. There was no big bang, no initial singularity. Instead we have an eternal inflationary universe, which may or may not possesses an initial singularity (t = 0) itself, and our universe (and I don't mean O.U., I do mean our whole Universe) is just a bubble within it, a true vacuum state in a huge false vacuum universe. Of course, our bubble is not unique in any way, just one in many. But under that logic, t < 0 means the time in the inflationary universe when our bubble still hadn't been made. So, there is no "node", no "vertex".

 

[murongqingcao]

Problem is that on largest scale, matter seems to be distributed in "strands" rather than isolated clusters. There is no clear separation that would allow for some areas to have just matter and others just anti-matter.

Thanks for the explanation...however, when you said that 'on largest scale, matter seems to be distributed in "strands" rather than isolated clusters' you were based upon the observation of matters...when there were some strands of matters and some strands of anitmatters (both of which was of course much bigger than our current universe) nearby, the very neighborhood would annihilated with each other and left some wide space between them so that the initial "strands" ended up as isolated clusters...and the radiation as the result of this kind of anihilation would be hidden among the initial cosmic background radiation so that we would not see any extra gamma rays...is that possible?

Thanks

 

[JamesOrland]

Thanks for the explanation...however, when you said that 'on largest scale, matter seems to be distributed in "strands" rather than isolated clusters' you were based upon the observation of matters...when there were some strands of matters and some strands of anitmatters (both of which was of course much bigger than our current universe) nearby, the very neighborhood would annihilated with each other and left some wide space between them so that the initial "strands" ended up as isolated clusters...and the radiation as the result of this kind of anihilation would be hidden among the initial cosmic background radiation so that we would not see any extra gamma rays...is that possible?

Thanks

No, it's not really possible. The models we currently have of the universe suggest that it is ergodic (homogenous), there are no huge gaps like the one you mentioned. On a very very large scale, if you looked at the Universe (and could see it, of course, we are ignoring the whole lightspeed limit) you would see a pretty smooth sea of stars, with no separation whatsoever between them, and with patterns repeating every 10^10^115 metres.

 

[murongqingcao]

No, it's not really possible. The models we currently have of the universe suggest that it is ergodic (homogenous), there are no huge gaps like the one you mentioned. On a very very large scale, if you looked at the Universe (and could see it, of course, we are ignoring the whole lightspeed limit) you would see a pretty smooth sea of stars, with no separation whatsoever between them, and with patterns repeating every 10^10^115 metres.

thanks for the response...

I don't know why it is said that the matter in our whole universe is only 1 out of several billions of the matter and anitimatter at the beginning the big bang...

However, if that is true, then our current whole universe is the small cluster in the sense of statistical physics fluctuation...and thus what we can see as the strands in this universe might not be used as the absolute base for reasonning out of the whole if there are some other clusters like our universe left from the big bang time...

we cannot use what we see within the cluster to reason for what is outside the cluster, right?

 

[JamesOrland]

I don't know why it is said that the matter in our whole universe is only 1 out of several billions of the matter and anitimatter at the beginning the big bang...

Um... I'm pretty sure that is not said. Maybe the matter in our Observable Universe is but a fraction of the matter present at the time inflation ended, but the whole universe is infinite (as far as most recent evidence points, mind you).

However, if that is true, then our current whole universe is the small cluster in the sense of statistical physics fluctuation...and thus what we can see as the strands in this universe might not be used as the absolute base for reasonning out of the whole if there are some other clusters like our universe left from the big bang time...

we cannot use what we see within the cluster to reason for what is outside the cluster, right?

Well, for the answer to the last question, not so. We can use what we see within our cluster as a model of what other clusters might look like (here I'm using cluster to mean Observable Universe).

On the other hand, the evidence I'm talking about isn't only what's currently in our causally connected world, but also what once was under that category. I am going to thread again in dangerous territories here by talking about things of whose details I am not wholly sure. The λCDM model, which is the currently accepted model of the universe, states that the universe is mostly homogenous all around, and I do mean outside of our cluster. How they know that? I haven't a clue, but I think it has something to do with Cosmic Microwave Background Radiation. Of course, I might be just blabbering like a lunatic here, so I'm hoping that someone with a better understanding of such topics might help you here.

Or maybe you could ask about this at the Cosmology forum. They certainly know better than I do!

 

[murongqingcao]

Um... I'm pretty sure that is not said. Maybe the matter in our Observable Universe is but a fraction of the matter present at the time inflation ended, but the whole universe is infinite (as far as most recent evidence points, mind you).



Well, for the answer to the last question, not so. We can use what we see within our cluster as a model of what other clusters might look like (here I'm using cluster to mean Observable Universe).

On the other hand, the evidence I'm talking about isn't only what's currently in our causally connected world, but also what once was under that category. I am going to thread again in dangerous territories here by talking about things of whose details I am not wholly sure. The λCDM model, which is the currently accepted model of the universe, states that the universe is mostly homogenous all around, and I do mean outside of our cluster. How they know that? I haven't a clue, but I think it has something to do with Cosmic Microwave Background Radiation. Of course, I might be just blabbering like a lunatic here, so I'm hoping that someone with a better understanding of such topics might help you here.

Or maybe you could ask about this at the Cosmology forum. They certainly know better than I do!

James:

Thanks again for your kind explanation...here one source showing that the matter of our current universe is only 1 out of 2 billion of the matter and antimatter at the big bang:

The laws of nature require that matter and antimatter be created in pairs. But within a millifraction of a second of the Big Bang, matter somehow outnumbered its particulate opposite by a hair, so that for every billion antiparticles, there were a billion and one particles. Within a second of the creation of the universe, all the antimatter was destroyed, leaving behind only matter.

(link: http://www.exploratorium.edu/origins/cern/ideas/antimatter.html)

I agree that I should bring this to the cosmology forum...I could not find one on this site...maybe some other site.

Thanks