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## Main Question or Discussion Point

"I've looked this up and came up to similar questions but haven't seen it been explained very clear yet. Excuse me if such questions were already posted here.

There are two different kinds of simultaneity it seems to me:

Let's take the event of two lightning bolts striking earth. Observer A is positioned exactly in between the lightning strikes and sees the light of both bolts reaching him at the same time. Observer B, closer to bolt 1, will see bolt 1 happening before bolt 2. Observer C, closer to bolt 2, will see bolt 2 happening before bolt 1. So here we have people seeing a different order of events using a very classical reasoning. So no SR involved here.

(According to SR though, these observers should all see the same simultaneity for the bolts, since ##\beta=0## and ##\gamma=1##. This would mean ##\delta{t}=\delta{t'}## for any of those observers.)

The only explanation I came up with is that there exists some ''absolute simultaneity'' for all observers at rest relative to eachother. They can define for the simultaneity to be: ''all observers at rest to eachother should calculate how the person exactly in between the two events would percieve them, this is then the meaning of simultaneity in the context''.

So basically there is:

1) Simultaneity as in percieving the order of events without any calculations

2) Simultaneity as in, doing calculations based on how far you are from the two events and how long the time difference of arrival of lightf from the events is. Based on this you can conclude if they would have been simultaneous in the frame of a person excatly in between the events.

The question is now:

Please tell me if my reasoning is somewhat correct, and where it can be more accurate. Do I just forget about the simultaneity as defined in 1) and only think about it in terms of 2? This would mean that the if I drop a ball right now, and then in 8 minutes I look up and see a sunspot appearing on the sun, the dropping of the ball and the appearing of the sunspot would be simultaneous.

There are two different kinds of simultaneity it seems to me:

Let's take the event of two lightning bolts striking earth. Observer A is positioned exactly in between the lightning strikes and sees the light of both bolts reaching him at the same time. Observer B, closer to bolt 1, will see bolt 1 happening before bolt 2. Observer C, closer to bolt 2, will see bolt 2 happening before bolt 1. So here we have people seeing a different order of events using a very classical reasoning. So no SR involved here.

(According to SR though, these observers should all see the same simultaneity for the bolts, since ##\beta=0## and ##\gamma=1##. This would mean ##\delta{t}=\delta{t'}## for any of those observers.)

The only explanation I came up with is that there exists some ''absolute simultaneity'' for all observers at rest relative to eachother. They can define for the simultaneity to be: ''all observers at rest to eachother should calculate how the person exactly in between the two events would percieve them, this is then the meaning of simultaneity in the context''.

So basically there is:

1) Simultaneity as in percieving the order of events without any calculations

2) Simultaneity as in, doing calculations based on how far you are from the two events and how long the time difference of arrival of lightf from the events is. Based on this you can conclude if they would have been simultaneous in the frame of a person excatly in between the events.

The question is now:

Please tell me if my reasoning is somewhat correct, and where it can be more accurate. Do I just forget about the simultaneity as defined in 1) and only think about it in terms of 2? This would mean that the if I drop a ball right now, and then in 8 minutes I look up and see a sunspot appearing on the sun, the dropping of the ball and the appearing of the sunspot would be simultaneous.