Brent, No it's not "an observation that the two twins are together at particular spacetime coordinates" because the spacetime t coordinates are different.
Since the spacetime t coordinates are different WHEN are they together? Certainly not in a simultaneous clock time as proved by their differing clocks. When are they together Brent? Obviously in a present moment which is a kind of time that clearly is not the same as clock time. Edgar On Monday, January 6, 2014 12:18:16 AM UTC-5, Brent wrote: > > On 1/5/2014 12:00 PM, Edgar L. Owen wrote: > > Brent, > > > > No, the present moment is NOT just a "label". It's an empirically > verifiable observation > > (measurement). And not only that both twins agree on that measurement, > namely that they > > have different clock times in the same shared present moment. > > > > There is simply no way around that.... > > > > Edgar > > Of course it's an observation. It's an observation that the two twins are > together at > particular spacetime coordinates. I have no problem with you calling that > a present > moment (although everyone else calls it an event). The problem is not > that you can't > define a global time at which they meet, it's that you can't define a > *unique* global > time. There are infinitely many choices of coordinate time and they will > all agree that > the twins meet at the same coordinate time - but they will not agree as to > which other > distant events in the universe are at the same time as the meeting. > > Brent > -- You received this message because you are subscribed to the Google Groups "Everything List" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at http://groups.google.com/group/everything-list. For more options, visit https://groups.google.com/groups/opt_out.
