On Jul 14, 8:05 pm, "Whoever" <no...@nowhere.com> wrote: > "Bruce Richmond" <bsr3...@my-deja.com> wrote in message > > news:95471494-cc92-4d8c-b988-2de404f0dda8@i6g2000yqj.googlegroups.com... > > > > > > > On Jul 14, 4:11 am, "Whoever" <no...@nowhere.com> wrote: > >> "Spirit of Truth" <junehar...@prodigy.net> wrote in > >> messagenews:HHV6m.15653$bq1.7920@nlpi066.nbdc.sbc.com... > > >> > "Whoever" <no...@nowhere.com> wrote in message > >> >news:0077f42c$0$9680$c3e8da3@news.astraweb.com... > >> >> "Spirit of Truth" <junehar...@prodigy.net> wrote in message > >> >>news:vlT6m.10982$Jb1.3792@flpi144.ffdc.sbc.com... > > >> >>> "Sam Wormley" <sworml...@mchsi.com> wrote in message > >> >>>news:hJz6m.782029$yE1.228877@attbi_s21... > >> >>>> Spirit of Truth wrote: > > >> >>>>> Stop being such an uncompromising idiot. Go read Brian Greene's > >> >>>>> Best Sellers and when you understand a little about science come > >> >>>>> back and then open your at the moment idiot mouth. > > >> >>>>> Spirit of Truth > > >> >>>> That's really interesting that you suggest reading Brian Greene. > > >> >>>> 1. Brian Green gets relativity right! You don't! > > >> >>>> 2. Greene's book are loaded with "ifs" and "what ifs" and most lay > >> >>>> people cannot sort out the science from the speculation. I > >> >>>> think > >> >>>> you are one of those people, Spirit! > > >> >>> No, Sam. if you have Greene's books look up block universe > >> >>> which appears in both of them. > > >> >>> I have made no error whatsoever in my statements to you. > > >> >> Can you supply an excerpt. I don't have access to the book you are > >> >> referring to. > > >> >> BTW: You're still not said WHY the universe cannot be block, and how > >> >> you > >> >> could tell whether or not it is. Other than we have to take it on > >> >> faith > >> >> and your assurances. > > >> > I don't have time to do Greene for you, but have a read of the > >> > following > >> > conversation, I hope it posts OK: > > >> Thanks > > >> BTW: You do know that in SR if you and another observer are at the same > >> place now, regardless of your relative motion, you will experience > >> exactly > >> the same universe at that 'now'. Things the you see as simultaneous, > >> they > >> will see as simultaneous. > > > When I saw this I had to double check to make sure you had written the > > above and that you were not quoting someone else. The above is not > > correct. The obvious example is the train experiment. When M and M' > > coincide they are at the same place. For M the strikes are happening > > at A and B now. For M' the strike already happen at B before he met > > M, while the strike at A has yet to happen. > > But they EXPERIENCE the same things. What you experience is what you sense > .. what you sense is what happens where you are .. not at some other > location.
Somehow I don't think many readers would interpert "same universe" as meaning just the event happening at that one location the instant they are together. That is a mighty small universe. If you mean everything they can see from that spot at that one instant I think you will find things differ. I will explain further down. Also when we talk of simultaneity in SR we are usually speaking of events seperated by space. Technically I suppose you can say an event is simultaneous with itself, but that's begging for confusion.
> Indeed, it is impossible for something happening now somewhere > else to affect you. These are events in space-time at your location. And > the speed of an observer does not change events at some location. That's > why I used the word experience.
I think if you get detailed enough about what they see their experiences are different even when at the same spot. Again, further down.
> Perhaps it would be a little clearer if I worded it as "you will have the > same experience of the universe at the 'now'". > > An example is that if two observers meet, travelling at different speeds > (maybe one is walking past), .. for each of them a remote point at that time > in their mutual x-direction in (say) another galaxy will correspond to > different points in time in that remote galaxy. However, they will both have > identical experiences of that galaxy. So, if there was a telescope where > they pass, they would each see the same image of the galaxy from a single > time. Even though what they consider (but not experience) as 'now' in that > galaxy is different times.- Hide quoted text - > > - Show quoted text -
Try looking away from the x axis. Let's say N' is moving parallel to M' and is perpendicular to M'. In the path of N' lies N some distance in the -x direction from the y axis. When N' coincides with N a flash is emitted. The flash arrives at the location of M and M' just as they coincide.
M will see the flash coming from N, who is to the - side of the y axis. He will also see N' at that location. M' will see the flash come from N', who is perpendicular to him on the y' axis. M' will also see N at the flash.
So even though M and M' agree that N and N' were together when the flash happen, they don't agree on where the flash took place. And by that I don't mean the grid coordinates as reported by other observers, but what M and M' would see of distant events with their own eyes. If M and M' both point their (narrow field of view) telescopes perpendicular to the x axis M' will see the flash but M will not.
