Relativity and time question

[saltynuts]

I know that as you travel closer and closer to the speed of light time passes slower and slower for you versus people not traveling at the speed of light.<br /><br />Question: How can you tell which person is REALLY traveling at (near) the speed of light? They are moving away from each other at (near) the speed of light, so how can we be sure who will age fast and who will age slow?<br /><br />Thanks.<br /><br />

 

[Saiph]

well, you can't. So both points of view are valid.<br /><br />Each person will see the other age slower. And this isn't a problem until you bring the two people back together in one spot.<br /><br />Of course, to do that, one of them has to turn around...and then we "know" who moved, as only one of them feels the acceleration due to turning.<br /><br />That's how Special Relativity deals with it anyway. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[siarad]

Er not if in an orbit. Wherever you are is the centre of the Universe so they each appear stopped at all times with the other orbiting.<br />It's impossible to measure your speed w.r.t. C as the answer is always the same. Maxwell, M&M exp.

 

[Saiph]

Of course it isn't possible in an orbit...that acceleration. You can tell who's orbiting.<br /><br />I never said you measure your speed w.r.t. C. You measure it relative to eachother, or an observer, or some other mark. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>

 

[siarad]

<blockquote><font class="small">In reply to:</font><hr /><p>Question: How can you tell which person is REALLY traveling at (near) the speed of light?<p><hr /></p></p></blockquote><br />Sorry I was replying to the question

 

[Saiph]

ahh, gotcha. <div class="Discussion_UserSignature"> <p align="center"><font color="#c0c0c0"><br /></font></p><p align="center"><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">--------</font></em></font><font color="#999999"><em><font size="1">----</font></em></font><font color="#666699">SaiphMOD@gmail.com </font><font color="#999999"><em><font size="1">-------------------</font></em></font></p><p><font color="#999999"><em><font size="1">"This is my Timey Wimey Detector.  Goes "bing" when there's stuff.  It also fries eggs at 30 paces, wether you want it to or not actually.  I've learned to stay away from hens: It's not pretty when they blow" -- </font></em></font><font size="1" color="#999999">The Tenth Doctor, "Blink"</font></p> </div>