Horizons/power/photons

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SpeedFreek

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Wow, this thread is getting ridiculous. I wonder if the original poster feels that his question was addressed. It is good to question things and look at things from different points of view and to question fundamentals while maintaining, of course, a good hold on logic (courtesy and humility too). The only thing I've learned from this thread is that a frame of reference moving at the speed of light is not considered an inertial frame by definition based on the assumptions of current theory. To question that seems to cause nothing but bickering. That is the nonsense ! Not the question. <br /> Posted by UncertainH</DIV></p><p>You should have also learned by the 5th post of this thread, that cosmological event horizons are distant relative to the observer - you cannot be at your own horizon, which was the main point of the question. What a photon, or anyone else would observe if they were "at" the horizon is therefore a moot point as, wherever you are in the universe right now, your cosmological event horizon would be 16 billion light years away from you. There are galaxies up to 46 billion light-years away (co-moving distance, or where things are now), but we will never see events that happen today at distances greater than 16 billion light-years away. We ourselves are at the cosmological event horizon of a galaxy that is currently 16 billion light-years away.</p><p>If you take nothing else from this thread with you, at least take this much!&nbsp; <img src="http://sitelife.space.com/ver1.0/content/scripts/tinymce/plugins/emotions/images/smiley-wink.gif" border="0" alt="Wink" title="Wink" /> </p> <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>
 
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derekmcd

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<p>VanDivx,</p><p>I won't respond line by line with your response.&nbsp; What I can say is that some of your responses were much more clearly defined than your original post.&nbsp; I'll bet if you went back and rewrote your post using real terms that physicists use, your post would have made more sense and I wouldn't have considered it mumbo jumbo.</p><p>For example, had you simply stated that a photon is a quanta of energy rather than "photon of energy", it would have made much more sense.&nbsp; Same applies to "localized particle form".&nbsp; Just use the terms physicists use and don't concern yourself if the readers of the thread understand the terms.&nbsp; They can look them up if they don't understand.&nbsp; When you start using your own terms, it's nearly impossible to research, interpret and make sense of what you are saying.&nbsp;</p><p>And, if you are going to question the validity of SR and wave-particle duality, you should be prepared for criticism.&nbsp; Especially when your presentation is unclear and not very scientific.</p><p>It's all about presentation.&nbsp;</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>
 
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derekmcd

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>Wow, this thread is getting ridiculous. I wonder if the original poster feels that his question was addressed. It is good to question things and look at things from different points of view and to question fundamentals while maintaining, of course, a good hold on logic (courtesy and humility too). The only thing I've learned from this thread is that a frame of reference moving at the speed of light is not considered an inertial frame by definition based on the assumptions of current theory. To question that seems to cause nothing but bickering. That is the nonsense ! Not the question. <br /> Posted by UncertainH</DIV></p><p>I would argue that the reference frame of a photon is valid.&nbsp; However, it's not very meaningful as you can derive much useful information from it other than to describe infinities.&nbsp;</p> <div class="Discussion_UserSignature"> <div> </div><br /><div><span style="color:#0000ff" class="Apple-style-span">"If something's hard to do, then it's not worth doing." - Homer Simpson</span></div> </div>
 
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SpeedFreek

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<p>If anyone is interested, here is an archived post from sci.physics.relativity by Chris Hillman, that is relevent to this thread (and is very interesing in itself!)</p><pre><font size="3">Subject: Re: Question: Minkowski interval for lightlike separated events</font></pre><p>&nbsp;</p> <div class="Discussion_UserSignature"> <p><font color="#ff0000">_______________________________________________<br /></font><font size="2"><em>SpeedFreek</em></font> </p> </div>
 
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vandivx

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'>I am referring to the shift in simultaneity experienced by the twins in the twins "paradox". It has little to do with the length of the path that light has to travel from the event to the observer. When the twin returns from his relativistic journey, he finds he is younger than his twin who essentially stayed in an inertial frame of reference throughout. To return, the travelling twin had to turn around, and during the turnaround the travelling twin is not in an inertial frame of reference. The more distant the two twins are when one turns around, the larger the shift in simultaneity.The relativity of simultaneity is not about light-travel time - do you remember us having this conversation before? &nbsp; <br /> Posted by SpeedFreek</DIV></p><p>now that you mention it, yes, I remember</p><p>sorry for not answering sooner, I was so put off by the recent match I had here that coming back to the forum was like going to a dentist to have a tooth pulled and I needed few days break and I think I will take some more</p><p>&nbsp;</p><p>I have never understood this kind of relativity of simultaneity, I have seen it described before with the following modification (not sure even if it was made by you) to make it stand out more: that one could make the reversal of travel happen in a very short time (making the acceleration very large) and that in that case one would have seen a sudden big jump in time shift - jump in aging of both twins as one of them regarded the other as per some special methods of communication that would comply with SR -that&nbsp; the traveling twin would have seen the stay at home twin suddenly aged and vice versa</p><p>&nbsp;</p><p>that seems to me like some trick which in any case shouldn't result in absolute time difference in clock time, here in the differential physical aging of the twins, I understand that absolute time difference happens during acceleration and perhaps this shift in simultaneity is a method to account for that on the grounds of SR alone (without having to employ GR) </p><p>but if so, I understand that the time dilation accumulated during that part of the trip that is spent accelerating is not sufficient to account for all of the time difference in the twin thought experiment (or rather in the analogous real experiments that were made) and that not negligible part of the time differences comes from the motion of the twin at the uniform velocity (part of the trip spent just coasting along)&nbsp; </p><p>&nbsp;</p><p>and the whole issue is whether the time dilation which is physically accumulating (and which then results in differential aging of the twins) happens at all during the coasting part of the trip - because if it does, then SR is not really relative anymore as it should be</p><p>that's why I don't see the shift in simultaneity as important either way </p> <div class="Discussion_UserSignature"> </div>
 
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vandivx

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<p><BR/>Replying to:<BR/><DIV CLASS='Discussion_PostQuote'> I'll bet if you went back and rewrote your post using real terms that physicists use, your post would have made more sense and I wouldn't have considered it mumbo jumbo.For example, had you simply stated that a photon is a quanta of energy rather than "photon of energy", it would have made much more sense.&nbsp; Same applies to "localized particle form".&nbsp; Just use the terms physicists use and don't concern yourself if the readers of the thread understand the terms.&nbsp; They can look them up if they don't understand.&nbsp; When you start using your own terms, it's nearly impossible to research, interpret and make sense of what you are saying.&nbsp;And, if you are going to question the validity of SR and wave-particle duality, you should be prepared for criticism.&nbsp; Especially when your presentation is unclear and not very scientific.It's all about presentation.&nbsp; <br /> Posted by derekmcd</DIV></p><p>I admit you got a point, on the other hand my reason for posting like I do is that I find the offical established terminology intellectually stifling in that it has become a sort of like mantra over the half century of constant use which students just comfortably recite without really understanding underlying physics of QM</p><p>for example I think&nbsp;those slick phrases of classical Copenhagen QM interpretation in particular are deadly in this way, how else to explain that QM is today still tought precisely the way it was when Bohr died, virtually all key phrases are unchanged, and not even such timid steps expanding or changing the interpretation like I made in my post weren't put forward in all those years, makes it look like everybody has his hands so full of coming to grips with QM as it stands that nobody ventured to work on its interpretation to squeeze some more understanding out of it </p><p>&nbsp;</p><p>and everybody is so mesmerized by the offical terminology that if one leaves it its confines one little bit, one stops being understood</p><p>that's how I see it, however I admit you got a point too but normally we would have a give and take in explaining and there would be no need to slip into acerbic tones, that part of discussion puts me off so much (even if I win the argument sometimes) that I don't dare to come out with more involved new theories because before I could explain I would be accused of breaking way too much of physics and automatically taken for a crank, only chance one might have is with minute improvements to a very small area of physics with overall consequences no larger than a fly can make to an elephant when it lands on his back </p><p>&nbsp;</p> <div class="Discussion_UserSignature"> </div>
 
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