3 ms·

I'm pretty sure they have very compelling reasons to believe that distant galaxies are NOT made of anti-matter. Here is one I found in a quick search: The bo

I'm pretty sure they have very compelling reasons to believe that distant galaxies are NOT made of anti-matter. Here is one I found in a quick search: The boundary between any group of anti-matter galaxies and the region of space where matter is dominant should emit gamma rays, as the intergalactic wind pushes dust particles made of regular matter into one of the anti-matter galaxies. We don't see such gamma ray emissions in our observations of the cosmos. Source: https://www.forbes.com/sites/briankoberlein/2016/12/27/could-some-distant-galaxies-be-made-of-antimatter/ https://www.forbes.com/sites/briankoberlein/2016/12/27/could...

philipov 9y ago
What if all the antimatter-dominated regions are outside our cosmological horizon and are no longer in causal contact with matter-dominated regions?
- Retric 9y ago
  That just creates the same questions for why this region of space is so dominated by 'matter' while adding a new one that another vast region of space is dominated by 'anti-matter'. If you can come up with some compelling mechanism for it then sure it may be possible, but currently that seems to be more complex and fails to provide any support of any kind.
  - philipov 9y ago
    It's pure speculation, but I am suggesting that instead of some sort of annihilation imbalance, the mechanism might be a sorting process that causes antimatter and matter to collect into horizon-shaped pockets. If there were such a sorting process that was inherently linked to cosmological horizons, it could explain both where the antimatter went, and why we don't see an annihilation zone where the boundaries meet.
    - platz 9y ago
      Unfortunately one can use the anthropic principle to say anything about science beyond the horizon, since anything beyond the horizon is unobservable
    - Retric 9y ago
      The problem is your sorting process is identical to your original statement. It's like saying "why is the sky blue" > "air is blue". You need to make predictions that are different from your observations. On the other hand if you say something like "Air becomes blue when it's colder." Then you can actually test what's going on and falsify the statement which may lead to progress. Suppose you suggest the output of this experiment will change over time. Now, waiting a billion years is not going to happen but adding even more digits of accuracy may be possible.
excalibur 9y ago
Thanks for doing my research for me. This is why you should always google before you post :) I could edit my original comment to be more accurate and make a more limited point, but it's probably best to let it stand as-is, for anyone else who may have similar thoughts.

philipov 9y ago

What if all the antimatter-dominated regions are outside our cosmological horizon and are no longer in causal contact with matter-dominated regions?

Retric 9y ago
That just creates the same questions for why this region of space is so dominated by 'matter' while adding a new one that another vast region of space is dominated by 'anti-matter'. If you can come up with some compelling mechanism for it then sure it may be possible, but currently that seems to be more complex and fails to provide any support of any kind.
- philipov 9y ago
  It's pure speculation, but I am suggesting that instead of some sort of annihilation imbalance, the mechanism might be a sorting process that causes antimatter and matter to collect into horizon-shaped pockets. If there were such a sorting process that was inherently linked to cosmological horizons, it could explain both where the antimatter went, and why we don't see an annihilation zone where the boundaries meet.
  - platz 9y ago
    Unfortunately one can use the anthropic principle to say anything about science beyond the horizon, since anything beyond the horizon is unobservable
  - Retric 9y ago
    The problem is your sorting process is identical to your original statement. It's like saying "why is the sky blue" > "air is blue". You need to make predictions that are different from your observations. On the other hand if you say something like "Air becomes blue when it's colder." Then you can actually test what's going on and falsify the statement which may lead to progress. Suppose you suggest the output of this experiment will change over time. Now, waiting a billion years is not going to happen but adding even more digits of accuracy may be possible.

excalibur 9y ago

Thanks for doing my research for me. This is why you should always google before you post :) I could edit my original comment to be more accurate and make a more limited point, but it's probably best to let it stand as-is, for anyone else who may have similar thoughts.