iSoul In the beginning is reality

Conventions of here and now

This follows a post on synchrony conventions here. The question is, What is the meaning of here and now for what is observed? Is everything than an observer observes part of their here and now? Some things observed may be a long distance away. Some things observed may be from signals sent in the past, such as distant starlight.

There is no one correct answer. A convention is needed to define here and now. The usual convention is that here and now only apply to what is within a minimal distance and a minimal span of time, or what is at the same point in space and time as the observer.

But consider how we speak about what we observe. We don’t say, Look, there’s the sun as it was 8 minutes and 20 seconds ago. Nor do we say, Look, there’s the north star as it was 433.8 years ago. Instead, we speak of where the sun and stars are now, even though they are a long distance away.

It’s similar concerning distance. Go into the countryside, away from lights at night and observe the stars. There are so many of them – and they are so close. People say things such as: The stars are close here. Or: I’m closer to the stars here. So the stars can be here, even though they are a long distance away.

If we accept that everything observed here and now is here and now, then the incoming light is instantaneous, and its speed is infinite. For the round-trip speed of light to equal c, that means the outgoing speed of light equals c/2. This looks strange, but it is consistent with the way we speak.

It is also consistent with other modes. If we measure our commuting speed and send this information to someone else, the communication time is ignored, that is, the communication is considered instantaneous. One may say that relativistic effects are ignored, but that is equivalent to saying that the communication is effectively at an infinite speed.

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