Can a causal or time-like structure emerge without assuming a metric?

[Dale]

Would you like it if I answered via the same info but in my less prfessional way of talking/speech?

100%. Without any doubt or hesitation.

 

[robphy]

@OmniThoughts Please don't post chatbot output here. If any of us wanted to have a conversation with a chatbot then we would just ask them directly.

Probably off-topic, how would one even type an em-dash in the forum software?

 

[renormalize]

I just asked the chatbot to refine my findings into a more professional and much less verbose way to answer the question. Would you like it if I answered via the same info but in my less prfessional way of talking/speech?

@OmniThoughts, by joining this forum you agreed to abide by all the rules stated here:

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Sep 2, 2003

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Application and...

• Greg Bernhardt
• Replies: 2
• Forum: Feedback and Announcements

• 

In particular:
ChatGPT and AI-generated text

• Posting AI-generated text without attribution is categorically disallowed and will lead to a warning and an eventual permanent ban with continued use.
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Simply put, AI generated answers are explicitly prohibited here. So yes, please formulate your posts using your own words.

 

[OmniThoughts]

Yes a causal or timelike structure can occur without assuming a metric because of the network of relations via cause and effect, since interactions cause propagations from a source at natural speed-limit speeds, and the leave traces that can be observed and measured which enables us to be able to figure parts of the related causal order, it happens/happened naturally no matter if measuring-capable existences exist/existed or never exist/existed.

Everything happening in space sends out energy that travels to us, which/that proves those events happened exactly "when and where" they did. It's proven due to because energy from exploding stars and spinning stars arrive at exact times matching the "however long" distances they traveled. And the energy from the start of the universe caused the galaxies to be where they are today.

Supernova 1987A is an example of the timing of our detectong neutrinos three hours before we saw the light and both the neurinos and the light traveled 168,000 years, without needing to be "observed in order to happen". Pulsars send out energy like clockwork and match general relativity’s predictions to the nanosecond, which proves non-local time is happening without needing to be "observed in order to happen". Galaxies' shapes and locations are the results of how they formed from energy left over from like the beginning of the universe, the galaxies already exist which implies that whatever events caused their shapes/locations/formations happened billions of years ago without needing to be "observed in order to happen".

 

[renormalize]

Yes a causal or timelike structure can occur without assuming a metric because of the network of relations via cause and effect ...

OK, this is a response to the OP's original question about the possible structure underlying classical spacetime. But you then write:

... the galaxies already exist which implies that whatever events caused their shapes/locations/formations happened billions of years ago without needing to be "observed in order to happen".

which reads like a version of the question "Does the moon exist when no one is looking at it?", sometimes raised in debates about the role of the observer in quantum mechanics. Can you be more explicit about how and why this is relevant to the OP's interest in pre-metric structure in classical relativity?

 

[PeterDonis]

the network of relations via cause and effect, since interactions cause propagations from a source at natural speed-limit speeds, and the leave traces that can be observed and measured which enables us to be able to figure parts of the related causal order

How is this different from a Lorentzian metric?

 

[OmniThoughts]

I answered the question with "Yes a causal or timelike structure can occur without assuming a metric because of the network of relations via cause and effect, since interactions cause propagations from a source at natural speed-limit speeds, and leave traces that can be observed and measured which enables us to be able to figure parts of the related causal order, it happens/happened naturally no matter if measuring-capable existences exist/existed or never exist/existed.”, but I got a little off-topic with the rest where I was going on about whether observation is necessary for stuff to be/occur.

 

[OmniThoughts]

How is this different from a Lorentzian metric?

I was simply saying that causal structure is via the universe's natural activity and such exists/occurs independent of any metric we try to impose.

 

[renormalize]

I was simply saying that causal structure is via the universe's natural activity and such exists/occurs independent of any metric we try to impose.

The natural activity you describe is indeed direct empirical evidence for the existence of a Lorentzian metric on spacetime, from which causality then logically follows. But that's not what the OP is asking about. Instead, they want to know if there is a theoretical way to derive that metric from some simpler, pre-existing causal structure. As far as I can see, your empirical observations in no way address that second question.

 

[OmniThoughts]

The natural activity you describe is indeed direct empirical evidence for the existence of a Lorentzian metric on spacetime, from which causality then logically follows. But that's not what the OP is asking about. Instead, they want to know if there is a theoretical way to derive that metric from some simpler, pre-existing causal structure. As far as I can see, your empirical observations in no way address that second question.

I would think that that would be like trying to figure out what circumstances (regarding circumstances captured in a still photo) are supposed to result (from the still photo's circumstances) from what's happening in a still photo. One wouldn't be able to know unless sufficient extent/parts of the universe's natural laws/rules are known beforehand and can be utilized to do such a prediction or figuring out, and even then it might only be able to be known that way if the universe actually does temporally progress deterministically.

The natural activity you describe is indeed direct empirical evidence for the existence of a Lorentzian metric on spacetime, from which causality then logically follows. But that's not what the OP is asking about. Instead, they want to know if there is a theoretical way to derive that metric from some simpler, pre-existing causal structure. As far as I can see, your empirical observations in no way address that second question.

The natural activity you describe is indeed direct empirical evidence for the existence of a Lorentzian metric on spacetime, from which causality then logically follows. But that's not what the OP is asking about. Instead, they want to know if there is a theoretical way to derive that metric from some simpler, pre-existing causal structure. As far as I can see, your empirical observations in no way address that second question.

I would think that that would be like trying to figure out what circumstances (regarding circumstances captured in a still photo) are supposed to result (from the still photo's circumstances) from what's happening in a still photo. One wouldn't be able to know unless sufficient extent/parts of the universe's natural laws/rules are known beforehand and can be utilized to do such a prediction or figuring out, and even then it might only be able to be known that way if the universe actually does temporally progress deterministically.

 

[PeterDonis]

I was simply saying that causal structure is via the universe's natural activity and such exists/occurs independent of any metric we try to impose.

We don't "impose" a metric. We figure out what it is by looking at "the universe's natural activity" and the causal structure it implies. So what you're basically saying is, we know the metric because we know the metric. Which doesn't address the question being discussed in this thread at all.

 

[PeterDonis]

I would think that that would be like trying to figure out what circumstances (regarding circumstances captured in a still photo) are supposed to result (from the still photo's circumstances) from what's happening in a still photo.

No, because we don't just have one "still photo" of observations. We observe things happening over the course of time. So time is part of what we observe.