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Came across an article of interest claiming SR implies the future is predetermined. The salient argument is summarized below:

We start with the notion that we cannot attribute reality to the future since it is yet to be determined. Nor can we claim that what we see is real in the present because, if we are looking at distant light sources, we only see them as they were in the past. One definition of reality would be: “all that exists, now, here and elsewhere” This avoids things that do not exist anymore and things that do not yet exist.

Consider a Minkowski diagram having space as abscissae and time in ordinates. At time t = 0 an observer J located at the origin of an inertial system S would regard as objectively real all events that lie on the X axis (i.e., simultaneous with the presence of J at the origin at t = 0). But if another inertial frame S1 is considered that is in uniform motion v wrt to S, an observer J1 at rest in S1 must attribute reality to all events happening at his present time t1 = 0. These events are different from those constituting the reality of J. Given the complete symmetry demanded by SR, if the reality line of J1 passes through the origin 0, all the events on the X1 axis whose equation is t1 = 0 with inclination determined by the relative velocity v can be considered equally real as those on the X axis.. In other words J1 will attribute reality to events in J’s future which are not part of his present reality.

To make it more meaningful, consider other observers P1 and P2 at different points along the positive X axis. These are all equivalent in their description of their present reality since the time t = 0 is the same for all of them. It is seen that the reality line of J1 will be intersected by the personal future(s) of P1 and P2 (you will need to draw the point X1 above X and a line from the origin through X1 with p1 and p2 somewhere spaced somewhere along the positive x axis, then dotted lines up from p1 and p2 to intersect the 0-X1 axis ...sorry the drawing gets scrambled when I copy it from the clipboard).

Since there can be an infinite number of reality lines corresponding to different velocity frames that all pass through the origin - each representing the present for some legitimate inertial observer - is the future fixed in every detail?'''''''

ct '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' X1

!

!

!____________________________________ X

0 ...........p1 ....................p2

We start with the notion that we cannot attribute reality to the future since it is yet to be determined. Nor can we claim that what we see is real in the present because, if we are looking at distant light sources, we only see them as they were in the past. One definition of reality would be: “all that exists, now, here and elsewhere” This avoids things that do not exist anymore and things that do not yet exist.

Consider a Minkowski diagram having space as abscissae and time in ordinates. At time t = 0 an observer J located at the origin of an inertial system S would regard as objectively real all events that lie on the X axis (i.e., simultaneous with the presence of J at the origin at t = 0). But if another inertial frame S1 is considered that is in uniform motion v wrt to S, an observer J1 at rest in S1 must attribute reality to all events happening at his present time t1 = 0. These events are different from those constituting the reality of J. Given the complete symmetry demanded by SR, if the reality line of J1 passes through the origin 0, all the events on the X1 axis whose equation is t1 = 0 with inclination determined by the relative velocity v can be considered equally real as those on the X axis.. In other words J1 will attribute reality to events in J’s future which are not part of his present reality.

To make it more meaningful, consider other observers P1 and P2 at different points along the positive X axis. These are all equivalent in their description of their present reality since the time t = 0 is the same for all of them. It is seen that the reality line of J1 will be intersected by the personal future(s) of P1 and P2 (you will need to draw the point X1 above X and a line from the origin through X1 with p1 and p2 somewhere spaced somewhere along the positive x axis, then dotted lines up from p1 and p2 to intersect the 0-X1 axis ...sorry the drawing gets scrambled when I copy it from the clipboard).

Since there can be an infinite number of reality lines corresponding to different velocity frames that all pass through the origin - each representing the present for some legitimate inertial observer - is the future fixed in every detail?'''''''

ct '''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''''' X1

!

!

!____________________________________ X

0 ...........p1 ....................p2

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