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Groups > sci.physics.relativity > #371016 > unrolled thread
| Started by | Omar Shabsigh <omar.shabsigh@gmail.com> |
|---|---|
| First post | 2015-11-28 04:36 -0800 |
| Last post | 2015-12-21 16:41 -0800 |
| Articles | 20 on this page of 222 — 24 participants |
Back to article view | Back to sci.physics.relativity
Faster than the speed of light Omar Shabsigh <omar.shabsigh@gmail.com> - 2015-11-28 04:36 -0800
Re: Faster than the speed of light "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-11-28 07:09 -0800
Re: Faster than the speed of light Gary Harnagel <hitlong@yahoo.com> - 2015-11-28 07:41 -0800
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-01 05:35 -0800
Re: Faster than the speed of light Ned Latham <nedlatham@internode.on.net> - 2015-12-02 05:13 -0600
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-02 22:47 +1100
Re: Faster than the speed of light Ned Latham <nedlatham@internode.on.net> - 2015-12-04 09:31 -0600
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-05 14:09 +1100
Re: Faster than the speed of light Ned Latham <nedlatham@internode.on.net> - 2015-12-06 09:42 -0600
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-07 10:57 +1100
Re: Faster than the speed of light Ned Latham <nedlatham@internode.on.net> - 2015-12-16 11:08 -0600
Re: Faster than the speed of light Gary Harnagel <hitlong@yahoo.com> - 2015-12-02 03:55 -0800
Re: Faster than the speed of light Ned Latham <nedlatham@internode.on.net> - 2015-12-04 09:35 -0600
Re: Faster than the speed of light Gary Harnagel <hitlong@yahoo.com> - 2015-12-04 09:43 -0800
Re: Faster than the speed of light Ned Latham <nedlatham@internode.on.net> - 2015-12-06 10:03 -0600
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-05 14:13 +1100
Re: Faster than the speed of light Ned Latham <nedlatham@internode.on.net> - 2015-12-06 10:07 -0600
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-02 10:40 -0600
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-12-02 17:43 +0000
Re: Faster than the speed of light Ned Latham <nedlatham@internode.on.net> - 2015-12-04 09:39 -0600
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-04 12:50 -0600
Re: Faster than the speed of light Ned Latham <nedlatham@internode.on.net> - 2015-12-06 10:28 -0600
Re: Faster than the speed of light RichD <r_delaney2001@yahoo.com> - 2015-12-04 09:38 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-04 12:53 -0600
Re: Faster than the speed of light RichD <r_delaney2001@yahoo.com> - 2015-12-05 01:55 -0800
Re: Faster than the speed of light Maciej Woźniak <mlwozniak@wp.pl> - 2015-12-05 11:49 +0100
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-05 18:06 -0800
Re: Faster than the speed of light Maciej Woźniak <mlwozniak@wp.pl> - 2015-12-06 10:25 +0100
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-06 08:41 -0600
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-06 07:45 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-07 11:06 +1100
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-07 13:22 -0600
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-07 15:04 -0800
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-07 15:10 -0800
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-08 17:08 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-09 12:13 +1100
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-08 18:35 -0800
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-08 19:41 -0800
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-10 18:07 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-09 15:08 +1100
Re: Faster than the speed of light Gary Harnagel <hitlong@yahoo.com> - 2015-12-09 03:43 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-09 13:02 -0600
Re: Faster than the speed of light Gary Harnagel <hitlong@yahoo.com> - 2015-12-09 11:18 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-09 15:25 -0600
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-09 14:27 -0800
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-09 22:41 +0000
Re: Faster than the speed of light "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-12-09 18:04 -0800
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-10 15:34 +0000
Re: Faster than the speed of light "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-12-10 19:21 -0800
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-11 23:17 +0000
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-10 00:14 -0600
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-09 23:58 -0800
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-10 15:33 +0000
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-10 11:39 -0600
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-10 18:31 +0000
Re: Faster than the speed of light RichD <r_delaney2001@yahoo.com> - 2015-12-10 15:49 -0800
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-10 16:41 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-10 22:50 -0600
Re: Faster than the speed of light Gary Harnagel <hitlong@yahoo.com> - 2015-12-11 04:07 -0800
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-11 23:37 +0000
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-11 20:05 -0600
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-11 18:18 -0800
Re: Faster than the speed of light Maciej Woźniak <mlwozniak@wp.pl> - 2015-12-12 09:55 +0100
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-11 05:43 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-11 20:24 -0600
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-11 18:39 -0800
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-11 18:54 -0800
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-12 02:22 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-12 12:00 -0600
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-12 11:56 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-12 17:25 -0600
Re: Faster than the speed of light Maciej Woźniak <mlwozniak@wp.pl> - 2015-12-13 01:15 +0100
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-13 00:19 +0000
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-12 17:24 -0800
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-13 18:49 -0800
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-12 18:20 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-13 14:58 +1100
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-12 20:24 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-12 14:00 +1100
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-12 02:48 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-12 22:38 +1100
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-12 09:25 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-13 13:12 +1100
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-12 20:08 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-13 16:01 +1100
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-13 05:34 -0800
Re: Faster than the speed of light alsor@interia.pl - 2015-12-13 06:53 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-13 18:58 -0600
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-13 21:02 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-15 18:42 -0600
Re: Faster than the speed of light mlwozniak@wp.pl - 2015-12-15 23:33 -0800
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-19 17:03 -0800
Re: Faster than the speed of light David Fuller <fuller.david@hotmail.com> - 2015-12-20 06:55 -0800
Re: Faster than the speed of light alsor@interia.pl - 2015-12-20 08:50 -0800
Re: Faster than the speed of light David Fuller <fuller.david@hotmail.com> - 2015-12-20 11:19 -0800
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-20 23:10 -0800
Re: Faster than the speed of light alsor@interia.pl - 2015-12-24 12:09 -0800
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-24 21:55 -0800
Re: Faster than the speed of light alsor@interia.pl - 2015-12-26 10:28 -0800
Re: Faster than the speed of light Omar Shabsigh <omar.shabsigh@gmail.com> - 2016-01-03 00:03 -0800
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-24 09:32 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-25 19:43 +1100
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2016-01-14 03:21 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2016-01-14 22:38 +1100
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2016-01-14 04:08 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2016-01-15 11:13 +1100
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-12 12:03 -0600
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-12 17:15 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-13 13:14 +1100
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-11 13:57 -0800
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-11 23:42 +0000
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-13 12:15 -0600
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-11 23:29 +0000
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-11 15:32 -0800
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-11 23:47 +0000
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-11 23:34 +0000
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-11 20:21 -0600
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-12 16:31 +0000
Re: Faster than the speed of light RichD <r_delaney2001@yahoo.com> - 2015-12-12 00:52 -0800
Re: Faster than the speed of light RichD <r_delaney2001@yahoo.com> - 2015-12-11 00:11 -0800
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-12 16:59 +0000
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-09 13:30 -0600
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-09 14:12 -0800
Re: Faster than the speed of light Plexippus Kritikos <plexik@laertesegidio.org> - 2015-12-09 22:32 +0000
Re: Faster than the speed of light RichD <r_delaney2001@yahoo.com> - 2015-12-10 15:37 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-13 12:50 -0600
Re: Faster than the speed of light John Heath <heathjohn2@gmail.com> - 2015-12-10 18:10 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-11 16:35 +1100
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-07 14:53 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-08 12:22 +1100
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-07 18:47 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-08 15:33 +1100
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-07 21:43 -0800
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-07 19:40 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-10 00:27 -0600
Re: Faster than the speed of light RichD <r_delaney2001@yahoo.com> - 2015-12-08 12:58 -0800
Re: Faster than the speed of light "Dono," <sa_ge@comcast.net> - 2015-11-28 07:56 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-11-29 15:50 +1100
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-11-30 16:21 +0000
Re: Faster than the speed of light "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-11-30 08:40 -0800
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-11-30 16:55 +0000
Re: Faster than the speed of light "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-11-30 09:28 -0800
Re: Faster than the speed of light "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-11-30 09:31 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-11-30 12:14 -0600
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-11-30 18:25 +0000
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-11-30 21:23 -0800
Re: Faster than the speed of light "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-11-30 21:50 -0800
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-11-30 22:20 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-01 17:38 +1100
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-11-30 22:50 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-01 11:02 -0600
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-01 17:40 +1100
Re: Faster than the speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-12-01 07:44 +0100
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-12-01 19:54 +0000
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-11-30 11:51 -0600
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-11-30 18:03 +0000
Re: Faster than the speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-12-01 07:41 +0100
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-01 19:11 +1100
Re: Faster than the speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-12-01 22:42 +0100
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-02 10:20 +1100
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-12-01 23:32 +0000
Re: Faster than the speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-12-02 00:53 +0100
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-12-02 00:03 +0000
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-02 11:14 +1100
Re: Faster than the speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-12-02 02:03 +0100
Re: Faster than the speed of light "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-12-01 19:33 -0800
Re: Faster than the speed of light "Ross A. Finlayson" <ross.finlayson@gmail.com> - 2015-12-02 10:34 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-02 22:49 +1100
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-02 10:21 -0600
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-12-02 17:30 +0000
Re: Faster than the speed of light RichD <r_delaney2001@yahoo.com> - 2015-12-03 09:21 -0800
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-04 10:00 +1100
Re: Faster than the speed of light Odd Bodkin <bodkinodd@gmail.com> - 2015-12-03 17:34 -0600
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-03 16:04 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-04 09:00 -0600
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-05 14:03 +1100
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-05 22:50 -0600
Re: Faster than the speed of light RichD <r_delaney2001@yahoo.com> - 2015-12-08 12:29 -0800
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-04 20:07 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-01 11:14 -0600
Re: Faster than the speed of light kenseto <setoken@att.net> - 2015-12-02 05:46 -0800
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-02 08:26 -0800
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-02 09:38 -0800
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-12-02 17:45 +0000
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-02 20:10 -0800
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-03 05:58 -0800
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-03 17:11 -0800
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-03 17:25 -0800
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-02 10:43 -0600
Re: Faster than the speed of light kenseto <setoken@att.net> - 2015-12-03 08:43 -0800
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-12-03 16:56 +0000
Re: Faster than the speed of light Odd Bodkin <bodkinodd@gmail.com> - 2015-12-03 12:41 -0600
Re: Faster than the speed of light kenseto <setoken@att.net> - 2015-12-03 13:29 -0800
Re: Faster than the speed of light Odd Bodkin <bodkinodd@gmail.com> - 2015-12-03 16:30 -0600
Re: Faster than the speed of light kenseto <setoken@att.net> - 2015-12-04 11:56 -0800
Re: Faster than the speed of light Odd Bodkin <bodkinodd@gmail.com> - 2015-12-04 16:52 -0600
Re: Faster than the speed of light kenseto <setoken@att.net> - 2015-12-07 05:58 -0800
Re: Faster than the speed of light Odd Bodkin <bodkinodd@gmail.com> - 2015-12-07 08:34 -0600
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-12-04 18:04 -0600
Re: Faster than the speed of light kenseto <setoken@att.net> - 2015-12-07 06:20 -0800
Re: Faster than the speed of light Odd Bodkin <bodkinodd@gmail.com> - 2015-12-07 08:35 -0600
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-01 11:52 -0800
Re: Faster than the speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-12-01 22:44 +0100
Re: Faster than the speed of light JanPB <filmart@gmail.com> - 2015-12-01 14:04 -0800
Re: Faster than the speed of light Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2015-12-01 23:54 +0100
Re: Faster than the speed of light Tom Roberts <tjroberts137@sbcglobal.net> - 2015-11-30 11:32 -0600
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-11-30 18:49 +0000
Re: Faster than the speed of light Poutnik <Poutnik4NNTP@gmail.com> - 2015-11-30 20:15 +0100
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-11-30 19:22 +0000
Re: Faster than the speed of light Poutnik <Poutnik4NNTP@gmail.com> - 2015-12-01 10:51 +0100
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-12-01 19:45 +0000
Re: Faster than the speed of light Poutnik <Poutnik4NNTP@gmail.com> - 2015-12-01 10:55 +0100
Re: Faster than the speed of light Carl Heinz Krüger <heinzkrueger@ubernetz.org> - 2015-12-01 19:48 +0000
Re: Faster than the speed of light Odd Bodkin <bodkinodd@gmail.com> - 2015-12-01 10:16 -0600
Re: Faster than the speed of light Adrian Ferent <adrferent@gmail.com> - 2015-12-02 10:20 -0800
Re: Faster than the speed of light fuller.david@hotmail.com - 2015-12-02 12:11 -0800
Re: Faster than the speed of light Adrian Ferent <adrferent@gmail.com> - 2015-12-21 13:45 -0800
Re: Faster than the speed of light Odd Bodkin <bodkinodd@gmail.com> - 2015-12-21 16:55 -0600
Re: Faster than the speed of light Ezra Farrow <ezrafa@dubtechno.org> - 2015-12-21 23:15 +0000
Re: Faster than the speed of light Sylvia Else <sylvia@not.at.this.address> - 2015-12-22 12:16 +1100
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-21 17:48 -0800
Re: Faster than the speed of light John Gogo <jfgogo22@yahoo.com> - 2015-12-21 16:41 -0800
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| From | Gary Harnagel <hitlong@yahoo.com> |
|---|---|
| Date | 2015-12-09 03:43 -0800 |
| Message-ID | <b4ec77e9-dbb0-449a-b4e2-d6c8ed01b63d@googlegroups.com> |
| In reply to | #371630 |
On Tuesday, December 8, 2015 at 9:08:40 PM UTC-7, Sylvia Else wrote: > > On 9/12/2015 12:08 PM, John Heath wrote: > > > > C] The most popular solution is to say the polarization of the > > entangled photons was undecided until the measurement is made. This > > will return non classical probabilities to classical probabilities. > > The soup no longer has a fly. This sounds like the Bohr theory of collapse-of-the-wave-function upon measurement. > If this were the case, and the measurements were made independently of > each other, then you'd expect no correlation between the measurements. > > Sylvia. And if collapse were correct, then entanglement would require FTL communication, wouldn't it? Does this not refute wave function collapse? Gary
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| From | Tom Roberts <tjroberts137@sbcglobal.net> |
|---|---|
| Date | 2015-12-09 13:02 -0600 |
| Message-ID | <obedndQEd4p_5_XLnZ2dnUU7_82dnZ2d@giganews.com> |
| In reply to | #371646 |
On 12/9/15 12/9/15 - 5:43 AM, Gary Harnagel wrote:
> And if collapse were correct, then entanglement would require FTL
> communication, wouldn't it? Does this not refute wave function collapse?
No. You are applying "wave function" incorrectly. This leads you to an incorrect
appreciation of "collapse".
Here's the story in non-relativistic QM (the story in QM is more complex, but
arrives at the same conclusion):
In such a Bell-type experiment, a pair of particles is prepared in an
"entangled" spin state, the particles are separated, and each particle's spin is
measured at spacelike-separated events. Correlations between the spin
measurements are observed that violate Bell's inequalities.
The way this is modeled in QM is that the preparation of the initial state
generates a spin wavefunction OF THE SYSTEM. Do NOT think of this as a
"wavefunction of each particle's spin", this is a SINGLE spin wavefunction for
the SYSTEM (consisting of two particles).
As usual in QM, to compute the probability of a given measurement one computes
the square of the overlap integral between the initial state and the appropriate
eigenfunctions of the operator corresponding to the measured property (the
result of the measurement is the eigenvalue). Here that operator is the product
of the spin operators for each individual particle. Doing the calculation, one
finds that only pairs of spins that conserve angular momentum have nonzero
overlap integrals [#].
(There is a position wavefunction as well, whose overlap
integral multiplies the overlap integral of the spins;
in this experiment the position overlap is always 1
because we measure the spins of the particles where they
are located.)
[#] In one of life's little ironies, in non-relativistic
QM the spin operators are irreducible representations
of the Lorentz group ("borrowed" from SR!). The overlap
integrals are called Clebsch-Gordon coefficients.
Note there is NOTHING "propagating between the measurements", and there is NO
"collapse of the wavefunction". There is just computations of the overlap
integrals for all possible measurement results and a tabulation of their
probabilities. The fact that there is a SINGLE spin wavefunction for the SYSTEM
is what "entangles" the results of measuring the individual particles' spins.
The "wavefunction collapse" comes after the measurement
OF THE SYSTEM, which (obviously) includes both particles.
As there is no "wavefunction for each particle", there
is nothing to "collapse" until the SYSTEM wavefunction
"collapses" to the result of the measurements of both
particles.
NOTE: I put "wavefunction collapse" in quotes because this
is an error-prone and rather obsolete interpretation of
QM. There are MUCH better interpretations today (see e.g.
Ballentine, _Quantum_Mechanics,_A_Modern_Development_).
The calculation in QM violates Bell's inequalities, because the spin
wavefunction is not "local" in the sense he used in deriving the inequalities.
Tom Roberts
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| From | Gary Harnagel <hitlong@yahoo.com> |
|---|---|
| Date | 2015-12-09 11:18 -0800 |
| Message-ID | <cbbf33f4-41a7-4cc4-a564-d06e34d6f4ee@googlegroups.com> |
| In reply to | #371692 |
On Wednesday, December 9, 2015 at 12:02:59 PM UTC-7, tjrob137 wrote: > > On 12/9/15 12/9/15 - 5:43 AM, Gary Harnagel wrote: > > > > And if collapse were correct, then entanglement would require FTL > > communication, wouldn't it? Does this not refute wave function collapse? > > No. You are applying "wave function" incorrectly. This leads you to an > incorrect appreciation of "collapse". Did Bohr look at it this way? I thought his idea of "collapse" was what happened when a measurement was made. Certainly, one can make a measurement on only ONE of the entangled particles. Doing that tells the one doing the measurement what the state of the other particle is. Of course, he can't communicate that to an observer at the other particle's position FTL. Gary
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| From | Tom Roberts <tjroberts137@sbcglobal.net> |
|---|---|
| Date | 2015-12-09 15:25 -0600 |
| Message-ID | <npqdnZSXYKXJAfXLnZ2dnUU7_82dnZ2d@giganews.com> |
| In reply to | #371693 |
On 12/9/15 12/9/15 - 1:18 PM, Gary Harnagel wrote:
> On Wednesday, December 9, 2015 at 12:02:59 PM UTC-7, tjrob137 wrote:
>> On 12/9/15 12/9/15 - 5:43 AM, Gary Harnagel wrote:
>>> And if collapse were correct, then entanglement would require FTL
>>> communication, wouldn't it? Does this not refute wave function collapse?
>>
>> No. You are applying "wave function" incorrectly. This leads you to an
>> incorrect appreciation of "collapse".
>
> Did Bohr look at it this way?
I don't know. But I suspect that if he thought about this he would, especially
in the light of Bell's work (see below).
> I thought his idea of "collapse" was what
> happened when a measurement was made.
Yes. But a measurement of the system, not just of a part of it.
QM is all about computing the probability of obtaining a given result from a
measurement. For the system I described, if one applies just the spin
eigenfunction for one particle's spin, one does NOT have an overlap integral
("square-root of probability"), one has a function of the other particle's spin
variables -- one must apply the other particle's spin eigenfunction to obtain an
overlap integral. As I said before, after measuring one particle, there's
nothing to "collapse" until the other spin is measured also -- at that point the
SYSTEM wavefunction "collapses" to the eigenfunction of the measured final state.
That is, the overlap integral is between the initial and final states OF THE
SYSTEM, and without both particles' spin eigenfunctions one does not have a
final state with which to compute it.
After phrasing it that way, I'm now confident Bohr would
agree, as he often emphasized the system (rather than its
parts). I remark that Bohr is no longer a relevant authority
-- we have learned A LOT about QM since his day.
As I said before, the crucial insight here is recognizing what the wavefunction
represents -- it represents the SYSTEM, not the individual particles. And the
underlying reason is because that is how it was prepared -- as a system
consisting of two particles with correlated spins.
You cannot prepare two one-particle systems and still have
their spins be correlated or "entangled" -- they could be
equal or opposite (or anything else), but would be independent
and uncorrelated; spin measurements on such pairs would not
violate the Bell inequalities.
Tom Roberts
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| From | JanPB <filmart@gmail.com> |
|---|---|
| Date | 2015-12-09 14:27 -0800 |
| Message-ID | <49b3285c-cd04-4e8d-9462-ea9cd3e29c95@googlegroups.com> |
| In reply to | #371701 |
On Wednesday, December 9, 2015 at 1:25:43 PM UTC-8, tjrob137 wrote:
> On 12/9/15 12/9/15 - 1:18 PM, Gary Harnagel wrote:
>
> > I thought his idea of "collapse" was what
> > happened when a measurement was made.
>
> Yes. But a measurement of the system, not just of a part of it.
>
> QM is all about computing the probability of obtaining a given result from a
> measurement. For the system I described, if one applies just the spin
> eigenfunction for one particle's spin, one does NOT have an overlap integral
> ("square-root of probability"), one has a function of the other particle's spin
> variables -- one must apply the other particle's spin eigenfunction to obtain an
> overlap integral. As I said before, after measuring one particle, there's
> nothing to "collapse" until the other spin is measured also -- at that point the
> SYSTEM wavefunction "collapses" to the eigenfunction of the measured final state.
There is still something going on here because after measuring the spin
of the first particle (let's say it's "up"), one can choose NOT to measure
the second particle's spin at a _spacelike_ connected event but at a timelike
connected one instead. (Say, after measuring the first spin, the observer
walks to the second particle and then measures it.)
And at this point the second particle's measurement will certainly yield
"down". So something must have changed in the wave function after measuring
the first particle already or else it wouldn't yield "down" with probability 1.
--
Jan
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| From | Plexippus Kritikos <plexik@laertesegidio.org> |
|---|---|
| Date | 2015-12-09 22:41 +0000 |
| Message-ID | <n4aand$sij$1@speranza.aioe.org> |
| In reply to | #371711 |
JanPB > As I said before, after >> measuring one particle, there's nothing to "collapse" until the other >> spin is measured also -- at that point the SYSTEM wavefunction >> "collapses" to the eigenfunction of the measured final state. You can't measure two spacelike separated disconnected things same time. > There is still something going on here because after measuring the spin > of the first particle (let's say it's "up"), one can choose NOT to > measure the second particle's spin at a _spacelike_ connected event but > at a timelike connected one instead. (Say, after measuring the first > spin, the observer walks to the second particle and then measures it.) :) so this how is done in the field, by cheating. > And at this point the second particle's measurement will certainly yield > "down". So something must have changed in the wave function after > measuring the first particle already or else it wouldn't yield "down" > with probability 1. I suspect this is how The Computer is answering when asked (look, observe). Which strongly indicate an unavoidable hardware resource limitation running The Simulation.
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| From | "Ross A. Finlayson" <ross.finlayson@gmail.com> |
|---|---|
| Date | 2015-12-09 18:04 -0800 |
| Message-ID | <5a9e540d-65df-41a8-8992-84950b764c17@googlegroups.com> |
| In reply to | #371715 |
On Wednesday, December 9, 2015 at 2:41:54 PM UTC-8, Plexippus Kritikos wrote: > JanPB > > > As I said before, after > >> measuring one particle, there's nothing to "collapse" until the other > >> spin is measured also -- at that point the SYSTEM wavefunction > >> "collapses" to the eigenfunction of the measured final state. > > You can't measure two spacelike separated disconnected things same time. > > > There is still something going on here because after measuring the spin > > of the first particle (let's say it's "up"), one can choose NOT to > > measure the second particle's spin at a _spacelike_ connected event but > > at a timelike connected one instead. (Say, after measuring the first > > spin, the observer walks to the second particle and then measures it.) > > :) so this how is done in the field, by cheating. > > > And at this point the second particle's measurement will certainly yield > > "down". So something must have changed in the wave function after > > measuring the first particle already or else it wouldn't yield "down" > > with probability 1. > > I suspect this is how The Computer is answering when asked (look, > observe). Which strongly indicate an unavoidable hardware resource > limitation running The Simulation. No, just an evident measurement / observation effect, which is explained variously in terms of power of experiment in two-way operationalism and configuration of experiment in sampling / counting terms. It's pretty simple, the closer you look the smaller the particles and bigger the universe, sampling and counting yields a signed value or delta from the scalar, discretization, then of events and rates of sampling or normalization / re-normalization. It seems along those lines. Your own mental machinery can find it easier grasped altogether of finite extents of resources of things, but even of the simple abstract there is the infinite and unbounded of things, even of the simple abstract. So, a "computer simulation" of sufficient sufficiency would simple enough find these same gedanken and results as of cosmology's unbounded (infinite) universe, and the "running constants" as of how they are often enough simply arranged 1, 0, infinity. Also you seem and sound the sock-puppet, not that there's anything wrong with that, so much as that there is. "The computer running my life did it" is not a suitably scientific perspective, for a suitable scientific perspective. Also it's no defense.
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| From | Plexippus Kritikos <plexik@laertesegidio.org> |
|---|---|
| Date | 2015-12-10 15:34 +0000 |
| Message-ID | <n4c616$2jn$3@speranza.aioe.org> |
| In reply to | #371718 |
Il giorno mercoledì Wed, 09 Dec 2015 18:04:22 -0800, "Ross A. Finlayson" <ross.finlayson@gmail.com> ha scritto: >> I suspect this is how The Computer is answering when asked (look, >> observe). Which strongly indicate an unavoidable hardware resource >> limitation running The Simulation. > > No, just an evident measurement / observation effect, > which is explained variously in terms of power of experiment in two-way > operationalism and configuration of experiment in sampling / counting > terms. You are not paying attention, on how the measurements and observations are defined (and what those really are). According to what you said, those are not necessary. They ARE necessary, proven by the FACT that you HAVE TO ASK. > It's pretty simple, the closer you look the smaller the particles and > bigger the universe, sampling and counting yields a signed value or > delta from the scalar, discretization, then of events and rates of > sampling or normalization / re-normalization. Unmitigated cretinism.
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| From | "Ross A. Finlayson" <ross.finlayson@gmail.com> |
|---|---|
| Date | 2015-12-10 19:21 -0800 |
| Message-ID | <34d9fa34-5574-40f6-9c6a-b8c646e706ce@googlegroups.com> |
| In reply to | #371752 |
On Thursday, December 10, 2015 at 7:34:03 AM UTC-8, Plexippus Kritikos wrote: > Il giorno mercoledì Wed, 09 Dec 2015 18:04:22 -0800, "Ross A. Finlayson" > <ross.finlayson@gmail.com> ha scritto: > > >> I suspect this is how The Computer is answering when asked (look, > >> observe). Which strongly indicate an unavoidable hardware resource > >> limitation running The Simulation. > > > > No, just an evident measurement / observation effect, > > which is explained variously in terms of power of experiment in two-way > > operationalism and configuration of experiment in sampling / counting > > terms. > > You are not paying attention, on how the measurements and observations are > defined (and what those really are). According to what you said, those are > not necessary. They ARE necessary, proven by the FACT that you HAVE TO ASK. > > > It's pretty simple, the closer you look the smaller the particles and > > bigger the universe, sampling and counting yields a signed value or > > delta from the scalar, discretization, then of events and rates of > > sampling or normalization / re-normalization. > > Unmitigated cretinism. Well, no, you are agreeing that measurement and observations are acts, not passivity. Then, this is not just the quantum effects but mostly it is the quantum effects (not of "only quantum states", but instead about "digital or binary decision", quantizing effects. You are agreeing, why no? Ciao.
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| From | Plexippus Kritikos <plexik@laertesegidio.org> |
|---|---|
| Date | 2015-12-11 23:17 +0000 |
| Message-ID | <n4fli2$ref$1@speranza.aioe.org> |
| In reply to | #371792 |
Il giorno mercoledì Thu, 10 Dec 2015 19:21:10 -0800, "Ross A. Finlayson" <ross.finlayson@gmail.com> ha scritto: >> > It's pretty simple, the closer you look the smaller the particles and >> > bigger the universe, sampling and counting yields a signed value or >> > delta from the scalar, discretization, then of events and rates of >> > sampling or normalization / re-normalization. >> >> Unmitigated cretinism. > > Well, no, you are agreeing that measurement and observations are acts, > not passivity. Then, this is not just the quantum effects but mostly it > is the quantum effects (not of "only quantum states", but instead about > "digital or binary decision", > quantizing effects. You are agreeing, why no? Ciao. DIGITAL has nothing to do inhere, and is at least an order higher then STATES, BITS or BINARY DECISION. The Computer doesn't even need to be "digital". I was talking about "resources" and "hardware" not necessarily tight related to "digital". You have to look at it through a wider window perspective. Actually I doubt something like this can even became visualible. You can't see it since you are part of the Simulation, not the Computer.
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| From | Tom Roberts <tjroberts137@sbcglobal.net> |
|---|---|
| Date | 2015-12-10 00:14 -0600 |
| Message-ID | <CumdnYTDS7O1hfTLnZ2dnUU7_82dnZ2d@giganews.com> |
| In reply to | #371711 |
On 12/9/15 12/9/15 4:27 PM, JanPB wrote:
> On Wednesday, December 9, 2015 at 1:25:43 PM UTC-8, tjrob137 wrote:
>> On 12/9/15 12/9/15 - 1:18 PM, Gary Harnagel wrote:
>>> I thought his idea of "collapse" was what
>>> happened when a measurement was made.
>> Yes. But a measurement of the system, not just of a part of it.
>> QM is all about computing the probability of obtaining a given result from a
>> measurement. For the system I described, if one applies just the spin
>> eigenfunction for one particle's spin, one does NOT have an overlap integral
>> ("square-root of probability"), one has a function of the other particle's spin
>> variables -- one must apply the other particle's spin eigenfunction to obtain an
>> overlap integral. As I said before, after measuring one particle, there's
>> nothing to "collapse" until the other spin is measured also -- at that point the
>> SYSTEM wavefunction "collapses" to the eigenfunction of the measured final state.
>
> There is still something going on here because after measuring the spin
> of the first particle (let's say it's "up"), one can choose NOT to measure
> the second particle's spin at a _spacelike_ connected event but at a timelike
> connected one instead. (Say, after measuring the first spin, the observer
> walks to the second particle and then measures it.)
[You have implicitly selected a pair of spin-1/2 particles
prepared in an initial state with total spin 0.]
Certainly one can do that. Everything I said still holds. There is no (direct)
time dependence at all: the wavefunction is the product of a space factor and a
spin factor; the space factor always has an overlap integral of 1 because we
measure each particle where it is located (regardless of when we choose to
measure it). The spin factor has no dependence on either space or time.
> And at this point the second particle's measurement will certainly yield
> "down". So something must have changed in the wave function after measuring
> the first particle already or else it wouldn't yield "down" with probability 1.
Not true -- nothing "changed" in the wavefunction, because it is the
wavefunction of the SYSTEM. It remains true that the only non-zero overlap
integral when the first particle is "up" has the second particle "down". This
has ALWAYS been true.
Remember that you must enumerate all possibilities for the
results of the measurement of the system (here measurements of
the spins of both particles), and calculate the probability
for each of them. For just up/down measurements, we have:
up/up=0% up/down=50%, down/up=50%, down/down=0%. The timing
of the two measurements makes no effect on this.
(These do not violate the Bell inequalities; violations occur
when the two detectors are on different axes.)
You seem to be trying to force this into a "wavefunction of the second
particle", but it is NOT -- it is a wavefunction OF THE SYSTEM (which consists
of two particles with correlated spins, because that is what was prepared).
Tom Roberts
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| From | JanPB <filmart@gmail.com> |
|---|---|
| Date | 2015-12-09 23:58 -0800 |
| Message-ID | <83d94e88-133c-4d42-8ea7-38e9550438ec@googlegroups.com> |
| In reply to | #371726 |
On Wednesday, December 9, 2015 at 10:14:02 PM UTC-8, tjrob137 wrote:
> On 12/9/15 12/9/15 4:27 PM, JanPB wrote:
> >
> > And at this point the second particle's measurement will certainly yield
> > "down". So something must have changed in the wave function after measuring
> > the first particle already or else it wouldn't yield "down" with probability 1.
>
> Not true -- nothing "changed" in the wavefunction, because it is the
> wavefunction of the SYSTEM. It remains true that the only non-zero overlap
> integral when the first particle is "up" has the second particle "down". This
> has ALWAYS been true.
But why can't we say that the measurement of the first particle's spin constituted
the measurement of the system?
IOW if we have, say, two spin-1/2 fermions (an electron and a positron) which we intend
to measure along the z-direction, then the spin state vector would be an antisymmetric
combination of the two spin states:
1/sqrt(2) * ( |up>|down> - |down>|up> )
...and after measuring the first particle is "up", the above state will collapse to |up>|down>.
Perhaps we are talking about the same thing using slightly different definitions.
Or did you mean the statistical operator before and after is the same?
--
Jan
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| From | Plexippus Kritikos <plexik@laertesegidio.org> |
|---|---|
| Date | 2015-12-10 15:33 +0000 |
| Message-ID | <n4c60f$2jn$1@speranza.aioe.org> |
| In reply to | #371736 |
Il giorno mercoledì Wed, 09 Dec 2015 23:58:06 -0800, JanPB <filmart@gmail.com> ha scritto: > On Wednesday, December 9, 2015 at 10:14:02 PM UTC-8, tjrob137 wrote: >> On 12/9/15 12/9/15 4:27 PM, JanPB wrote: >> > >> > And at this point the second particle's measurement will certainly >> > yield "down". So something must have changed in the wave function >> > after measuring the first particle already or else it wouldn't yield >> > "down" with probability 1. >> >> Not true -- nothing "changed" in the wavefunction, because it is the >> wavefunction of the SYSTEM. It remains true that the only non-zero >> overlap integral when the first particle is "up" has the second >> particle "down". This has ALWAYS been true. > > But why can't we say that the measurement of the first particle's spin > constituted the measurement of the system? Actually this is exactly what we says. > IOW if we have, say, two spin-1/2 fermions (an electron and a positron) > which we intend to measure along the z-direction, then the spin state > vector would be an antisymmetric combination of the two spin states: This is not what the entanglement stands for. You can't combine what you just said, according to a sea of good reasons, I guess. > 1/sqrt(2) * ( |up>|down> - |down>|up> ) > > ...and after measuring the first particle is "up", the above state will > collapse to |up>|down>. "Collapse" is an archaic ill defined terminology, given to an artefact phenomenon. (here, in your case, given to a hypothetical existent correlation among incompatible particles spin-state behavioural) > Perhaps we are talking about the same thing using slightly different > definitions. You definitely not. > Or did you mean the statistical operator before and after is the same? You apparently are using math expectation, but entanglement is not about that. (more fundamental than expectations)
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| From | Tom Roberts <tjroberts137@sbcglobal.net> |
|---|---|
| Date | 2015-12-10 11:39 -0600 |
| Message-ID | <gp-dnUBEK4dZJfTLnZ2dnUU7_8ydnZ2d@giganews.com> |
| In reply to | #371736 |
On 12/10/15 12/10/15 - 1:58 AM, JanPB wrote: > On Wednesday, December 9, 2015 at 10:14:02 PM UTC-8, tjrob137 wrote: >> On 12/9/15 12/9/15 4:27 PM, JanPB wrote: >>> And at this point the second particle's measurement will certainly yield >>> "down". So something must have changed in the wave function after measuring >>> the first particle already or else it wouldn't yield "down" with probability 1. >> Not true -- nothing "changed" in the wavefunction, because it is the >> wavefunction of the SYSTEM. It remains true that the only non-zero overlap >> integral when the first particle is "up" has the second particle "down". This >> has ALWAYS been true. > > But why can't we say that the measurement of the first particle's spin constituted > the measurement of the system? Because it is not a measurement of the system, it's just a measurement of part of the system. > IOW if we have, say, two spin-1/2 fermions (an electron and a positron) which we intend > to measure along the z-direction, then the spin state vector would be an antisymmetric > combination of the two spin states: > 1/sqrt(2) * ( |up>|down> - |down>|up> ) > ...and after measuring the first particle is "up", the above state will collapse to |up>|down>. (See a note explaining his notation below.) But that is NOT the state of the system, that is a combination of eigenfunctions for the two particles' spin operators. The initial state of the system is: |i> = |0> because it was prepared in a total spin zero state. The Clebsch-Gordan table for a spin 0 state overlapped with two spin-1/2 states: <0|up>|up> = 0 <0|up>|down> = sqrt(1/2) <0|down>|up> = -sqrt(1/2) <0|down>|down> = 0 Remember the probability of obtaining a measurement is the overlap integral squared. Note that "|up>|up>" is the tensor product of two spin-1/2 eigenfunctions with eigenvalue up. So the question you ask is really: what is this: <0|up> ? As I said before, the answer is: neither the wavefunction of the system nor an overlap integral; it is a function of the other particle's spin. It is NOT a wavefunction, as it does not represent the system. Note that the meaning of "system" is determined by what is prepared. Here that is two spin-1/2 particles with total spin 0. You are free to consider "preparation of those two particles and then measuring one of them" to be the preparation of another system consisting of just the second particle. But think VERY CAREFULLY about what this preparation means and what the initial state of that second particle is. In the example given, the first particle is found to be in state |up>, so the preparation of the system consisting of the second particle simply arranges for it to have initial state |down>. Note there is no "collapse" for this system, either: <down|up> = 0 <down|down> = 1 > Perhaps we are talking about the same thing using slightly different definitions. I don't think so. We seem to disagree on key concepts in non-rel QM: what is a "system"? what is a "wavefunction"? what is "preparation of a system"? what is "collapse of the wavefunction"? And I think you have not thought sufficiently about them, and how they relate to the theory. Read Ballentine [reference given earlier]. He provides a much better description and discussion than I remember from grad school. > Or did you mean the statistical operator before and after is the same? No. I meant what I said before and above. A wavefunction ONLY applies to a system, not to its parts; in non-rel QM, the system is defined by what is prepared. Note to readers: JanPB is using the common notation for specifying spin states: |up> is the eigenfunction of a particle's spin operator with eigenvalue "up" (result of a measurement). The label inside the bra (|) and the ket (>) can be any appropriate eigenvalue. The overlap integral between an initial state i and a final state f is written <i|f> -- the reversal of the bra-ket for i indicates complex conjugation, and the integration over all internal variables is implicit. Note that i and f are state labels (eigenvalues), while |i> and |f> are the corresponding eigenfunctions. In general one must specify the total spin, the axis along which spin is measured, and the eigenvalue along that axis; JanPB follows common practice in omitting the total spin and the axis, as they are constant throughout his discussion (total spin = 1/2, axis = z). This notation is more general than I mention here or we use above. Tom Roberts
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| From | Plexippus Kritikos <plexik@laertesegidio.org> |
|---|---|
| Date | 2015-12-10 18:31 +0000 |
| Message-ID | <n4cgeo$tl7$1@speranza.aioe.org> |
| In reply to | #371763 |
Il giorno mercoledì Thu, 10 Dec 2015 11:39:16 -0600, Tom Roberts <tjroberts137@sbcglobal.net> ha scritto: > The Clebsch-Gordan table for a spin 0 state overlapped with > two spin-1/2 states: > <0|up>|up> = 0 > <0|up>|down> = sqrt(1/2) no, but <0|up>|down> = sqrt(2)/2 > Remember the probability of obtaining a measurement is the > overlap integral squared. Note that "|up>|up>" is the tensor > product of two spin-1/2 eigenfunctions with eigenvalue up > So the question you ask is really: what is this: <0|up> ? Yes. > As I said before, the answer is: neither the wavefunction of the system > nor an overlap integral; it is a function of the other particle's spin. It > is NOT a wavefunction, as it does not represent the system. Agree. This is about discrete things, not wave continuum. > Note that the meaning of "system" is determined by what is > prepared. Here that is two spin-1/2 particles with total spin 0. This sounds like anti-spin. Why not. Once you have a half of a spin you may safely pretend to have an amount of half anti-spin. > You are free to consider "preparation of those two particles and then > measuring one of them" to be the preparation of another system consisting > of just the second particle. But think VERY CAREFULLY about what this > preparation means and what the initial state of that second particle is. No idea. Entirely greek to me. > In the example given, the first particle is found to be in state > |up>, so the preparation of the system consisting of the second > particle simply arranges for it to have initial state |down>. > Note there is no "collapse" for this system, either: > <down|up> = 0 <down|down> = 1 Are you just saying that "entanglement" is a FAKE, being about the way you "prepare" things primordially? Hence, ulterior proceeded "measurements" are not possible!! >> Perhaps we are talking about the same thing using slightly different >> definitions. > I don't think so. We seem to disagree on key concepts in non-rel QM: > what is a "system"? > what is a "wavefunction"? > what is "preparation of a system"? > what is "collapse of the wavefunction"? > And I think you have not thought sufficiently about them, and how they > relate to the theory. Agree. Me neither. > Read Ballentine [reference given earlier]. He provides a much > better description and discussion than I remember from grad school. You had this stuff in grad school?? Looks PhD-ish to me. >> Or did you mean the statistical operator before and after is the same? > No. I meant what I said before and above. A wavefunction ONLY applies to a > system, not to its parts; in non-rel QM, the system is defined by what is > prepared. > Note to readers: JanPB is using the common notation for specifying > spin states: |up> is the eigenfunction of a particle's spin > operator with eigenvalue "up" (result of a measurement). The label > inside the bra (|) and the ket (>) can be any appropriate eigenvalue. > The overlap integral between an initial state i and a final state f > is written <i|f> -- the reversal of the bra-ket for i indicates > complex conjugation, and the integration over all internal variables > is implicit. Note that i and f are state labels (eigenvalues), while > |i> and |f> are the corresponding eigenfunctions. In general one > must specify the total spin, the axis along which spin is measured, > and the eigenvalue along that axis; JanPB follows common practice > in omitting the total spin and the axis, as they are constant > throughout his discussion (total spin = 1/2, axis = z). You can't spin only a half. Either you spin, or you spin not. This spinning thing is definitely not measurable by instruments, hence not real. But good post. Thanks.
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| From | RichD <r_delaney2001@yahoo.com> |
|---|---|
| Date | 2015-12-10 15:49 -0800 |
| Message-ID | <70e72f49-b08c-4416-8d0a-009c2136bdf0@googlegroups.com> |
| In reply to | #371711 |
On December 9, JanPB wrote: >>> I thought his idea of "collapse" was what >>> happened when a measurement was made. > >> Yes. But a measurement of the system, not just of a part of it. >> QM is all about computing the probability of obtaining a given >> result from a measurement. For the system I described, if one >> applies just the spin eigenfunction for one particle's spin, one >> does NOT have an overlap integral, one has a function of the >> other particle's spin variables -- one must apply the other >> particle's spin eigenfunction to obtain an overlap integral. >> there's nothing to "collapse" until the other spin is measured also >> - at that point the SYSTEM wavefunction "collapses" to the >> eigenfunction of the measured final state. > > There is still something going on here because after measuring the > spin of the first particle (let's say it's "up"), one can choose > NOT to measure the second particle's spin at a _spacelike_ > connected event but at a timelike connected one instead. > > And at this point the second particle's measurement will certainly > yield "down". So something must have changed in the wave function > after measuring the first particle already or else it wouldn't > yield "down" with probability 1. I don't see the point of your objection - the issue pertains to non-local, FTL relationships. If the experiment is timelike, what is proved, what's being tested? -- Rich
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| From | JanPB <filmart@gmail.com> |
|---|---|
| Date | 2015-12-10 16:41 -0800 |
| Message-ID | <e9a63362-67dd-4d96-9051-d8062b475b9c@googlegroups.com> |
| In reply to | #371780 |
On Thursday, December 10, 2015 at 3:49:33 PM UTC-8, RichD wrote: > On December 9, JanPB wrote: > >>> I thought his idea of "collapse" was what > >>> happened when a measurement was made. > > > >> Yes. But a measurement of the system, not just of a part of it. > >> QM is all about computing the probability of obtaining a given > >> result from a measurement. For the system I described, if one > >> applies just the spin eigenfunction for one particle's spin, one > >> does NOT have an overlap integral, one has a function of the > >> other particle's spin variables -- one must apply the other > >> particle's spin eigenfunction to obtain an overlap integral. > >> there's nothing to "collapse" until the other spin is measured also > >> - at that point the SYSTEM wavefunction "collapses" to the > >> eigenfunction of the measured final state. > > > > There is still something going on here because after measuring the > > spin of the first particle (let's say it's "up"), one can choose > > NOT to measure the second particle's spin at a _spacelike_ > > connected event but at a timelike connected one instead. > > > > And at this point the second particle's measurement will certainly > > yield "down". So something must have changed in the wave function > > after measuring the first particle already or else it wouldn't > > yield "down" with probability 1. > > I don't see the point of your objection - the issue > pertains to non-local, FTL relationships. If the > experiment is timelike, what is proved, what's being > tested? I was asking Tom about his saying that "after measuring one particle, there's nothing to "collapse" until the other spin is measured also". This seems to run against the usual (and perhaps old-fashioned but anyway) interpretation of the state vector and the projection postulate. After measuring the spin of the first particle in the z-direction (say), the state vector collapses (projects) to one with the spin component of the second particle necessarily yielding "up" if we decide to measure it along the z-direction as well, _regardless_ of the separating interval being timelike or specelike. The reason this interpretation (despite being quaint to some) makes sense to some extent is that the second particle will _not_ necessarily yield "up" in the z-direction if the first particle hadn't been measured in the z-direction previously. IOW, the second particle has no way of knowing in advance what we are going to do with the first particle: the key question being: what if I suddenly decide to measure the first particle in the x-direction? -- Jan
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| From | Tom Roberts <tjroberts137@sbcglobal.net> |
|---|---|
| Date | 2015-12-10 22:50 -0600 |
| Message-ID | <MKednQk6LJWdy_fLnZ2dnUU7_8ydnZ2d@giganews.com> |
| In reply to | #371781 |
On 12/10/15 12/10/15 6:41 PM, JanPB wrote: > I was asking Tom about his saying that "after measuring one particle, > there's nothing to "collapse" until the other spin is measured also". > > This seems to run against the usual (and perhaps old-fashioned but anyway) > interpretation of the state vector and the projection postulate. No it doesn't. You keep trying to consider each particle separately -- that is WRONG, because the preparation was of a PAIR OF PARTICLES. There is no "wavefunction for each particle", there is ONLY a wavefunction OF THE PAIR. In all Bohr's writings, and all the QM classes I took, the wavefunction "collapses" AFTER A MEASUREMENT OF THE SYSTEM, because the measurement determines that it is in the eigenstate corresponding to the eigenvalue that was measured. That is what "collapse of the wavefunction" means, and it says NOTHING AT ALL about measuring part of a system, or any sort of "partial collapse" which you seem to be advocating. When you measure one particle, that has NOT determined the final state, so the wavefunction of the system cannot "collapse". > After > measuring the spin of the first particle in the z-direction (say), the > state vector collapses [...] No, it doesn't. because you have not measured THE SYSTEM, you only measured part of it. > The reason this interpretation (despite being quaint to some) makes sense > to some extent is that the second particle will _not_ necessarily yield > "up" in the z-direction if the first particle hadn't been measured in the > z-direction previously. IOW, the second particle has no way of knowing > in advance what we are going to do with the first particle: the key > question being: what if I suddenly decide to measure the first particle > in the x-direction? Part that is IRRELEVANT, and the rest is WRONG. Because the initial state of the system is |0>. You can decide however you like to measure the two particles, you ALWAYS compute the probability of the result in final state f as |<0|f>|^2, regardless of what f is. Yes, "the second particle has no way of knowing in advance what we are going to do with the first particle" -- BUT IT DOESN'T MATTER because we compute <0|f>, in which |f> represents the results of the measurements WHICH WERE MADE [#] (regardless of the time sequence in which they were made). <0|f> is independent of time (and space). [#] Measurements is plural when discussing measuring the spins of the individual particles. But such a pair of measurements is a single measurement OF THE SYSTEM. You MUST learn to think of the system, not the individual particles. Tom Roberts
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| From | Gary Harnagel <hitlong@yahoo.com> |
|---|---|
| Date | 2015-12-11 04:07 -0800 |
| Message-ID | <966af33c-95f7-4bcb-973d-8cce434c6b82@googlegroups.com> |
| In reply to | #371793 |
On Thursday, December 10, 2015 at 9:50:11 PM UTC-7, tjrob137 wrote: > > On 12/10/15 12/10/15 6:41 PM, JanPB wrote: > > > > I was asking Tom about his saying that "after measuring one particle, > > there's nothing to "collapse" until the other spin is measured also". > > > > This seems to run against the usual (and perhaps old-fashioned but anyway) > > interpretation of the state vector and the projection postulate. > > No it doesn't. You keep trying to consider each particle separately -- > that is WRONG, because the preparation was of a PAIR OF PARTICLES. There > is no "wavefunction for each particle", there is ONLY a wavefunction > OF THE PAIR. > > In all Bohr's writings, and all the QM classes I took, the wavefunction > "collapses" AFTER A MEASUREMENT OF THE SYSTEM, because the measurement > determines that it is in the eigenstate corresponding to the eigenvalue > that was measured. That is what "collapse of the wavefunction" means, > and it says NOTHING AT ALL about measuring part of a system, or any sort > of "partial collapse" which you seem to be advocating. > > When you measure one particle, that has NOT determined the final > state, so the wavefunction of the system cannot "collapse". Hmmm, a "system" can certainly be isolated in some extent from the rest of the universe, but in reality the rest of the universe is part of the system, however minor. Doesn't this mean that the waveform doesn't "collapse" until you have measured the whole universe? Gary
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| From | Plexippus Kritikos <plexik@laertesegidio.org> |
|---|---|
| Date | 2015-12-11 23:37 +0000 |
| Message-ID | <n4fmog$ref$5@speranza.aioe.org> |
| In reply to | #371804 |
Il giorno mercoledì Fri, 11 Dec 2015 04:07:39 -0800, Gary Harnagel <hitlong@yahoo.com> ha scritto: > Hmmm, a "system" can certainly be isolated in some extent from the rest > of the universe, but in reality the rest of the universe is part of the > system, however minor. Doesn't this mean that the waveform doesn't > "collapse" until you have measured the whole universe? No. I think JanPB is right. See my answer til Mr Tom. Once the one is measured (destructive), the other is *terminated* as well. Half entangled particles does not exists.
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