Antimatter Stars

[vandivx]

<blockquote><font class="small">In reply to:</font><hr /><p>if large bodies of antimatter, did exist sparodically through the cosmos<p><hr /></p></p></blockquote><br />I know the spirit in which you pose this possibility and the following my two cents are not meant as some come on against the point you are raising<br /><br />thing is, if there were some sporadic occurence of such boddies on such large scale (planets, stars...) wouldn't that neccessarily imply that half the universe (either half or more or less half) would be made of antimatter and then it wouldn't be sporadic occurence anymore and very likely it would manifest itself someway even in our neighbourhood? That is given that antimatter stars are not relegated to some outskirts of universe but are sporadically occuring throughout the universe...<br /><br />Because once you can have even single star, it is pretty well given that antimatter would be just as common as matter in universe because even one such antimatter star would mean that there is mechanism in nature through which it is possible that such thing can happen and once you have the possibility of such mechanism to work (without human causal intervention), there is no reason why is should work only sporadically and make just few stars. (the mechanism would have to involve some process separating the two kinds of matter in the first place so stars and galaxies etc could even start to form and have time to form etc but there is no such separating mechanism that we know of or can imagine)<br /><br />Nature just doesn't work like that from what our experince with it goes. I think it is pretty safe to assume that antimatter for some reason can't occur on large scale (such as to form large boddies) because it is 'forbiden' by something in nature which we don't understand yet.<br /><br />On the issue of the possibility there being macroscopic boddies of antimatter in universe existing in isolation, that has been discussed of course many times and the answer from reputable <div class="Discussion_UserSignature"> </div>

 

[vandivx]

<blockquote><font class="small">In reply to:</font><hr /><p>bushuser: If say--Andromeda--was an antimatter galaxy, would there be clues in our spectral analysis, our radio telescope data, or red shift? Can large isolated collections of antimatter be detected in the cosmos, or would it appear the same as ordinary matter?<p><hr /></p></p></blockquote>there would be no such clues or any other besides the anihilation reaction as a telling sign<br /><br />it would appear as ordinary matter since for example positron appart from its electric charge is just like electron in all respects and assignement of positive and negative signs to particle charge is completely relative thing, meaning it is purely arbitrary convention, electrons could have been assigned when discovered positive charge and protons negative and that would have been that and it would have been our terminology today.<br /><br />One can't tell if given radiation came from helium or antihelium atom, it is all the same and we can detect cosmic objects at distance only by means of their radiation of all kinds. Only way of detection if a star is made of antimatter (if we set aside crass anihilation, like if we invented antimatter shielding and you could land on antimatter planet as astronaut) would be to make experiments with its particles in situ so to speak (like measuring dipole moment of atoms or some such electromagnetic tests - but even here I have doubts as I didn't think about it from this angle before, I mean if the antimatter shielding would mean that you couldn't 'export' some charge from behind your shield onto the planet to test the antimatter planet's charged particles against your charged matter particle - because then you would be stuck and couldn't decide if you couldn't test against your normal matter from within your antimatter shield) but then if we could run such local experiments, we would find out what we are up against even without those experiments (unless we had such phantasy shield LOL). <br /><br />va <div class="Discussion_UserSignature"> </div>

 

[sponge]

Thanks for the educational answer vanDivX, I post threads to get educated answers on subjects I know little or nothing about. <br /><br />Cheers<br /><br />Sponge<br /> <div class="Discussion_UserSignature"> <p><em><u>SPONGE</u></em></p> </div>