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Author Topic: How should one interpret spacetime diagrams?  (Read 24127 times)

Online Bill S

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Re: How should one interpret spacetime diagrams?
« Reply #50 on: 05/04/2015 02:28:54 »
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I here argue that perfect inertial dragging may save the principle of relativity, and that this requires a new model of the Minkowski spacetime where the cosmic mass is represented by a massive shell with radius
equal to its own Schwarzschild radius.

Could someone translate this into lay-speak, please?
 

Offline jeffreyH

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Re: How should one interpret spacetime diagrams?
« Reply #51 on: 05/04/2015 03:37:08 »
Quote
I here argue that perfect inertial dragging may save the principle of relativity, and that this requires a new model of the Minkowski spacetime where the cosmic mass is represented by a massive shell with radius
equal to its own Schwarzschild radius.

Could someone translate this into lay-speak, please?

I would like it worded better too. Is inertial dragging related to the dragging of inertial frames for instance? Or something entirely different? What is the Schwarzschild radius of the cosmic mass? Isn't that infinite by definition?
 

Online Bill S

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Re: How should one interpret spacetime diagrams?
« Reply #52 on: 05/04/2015 18:44:17 »
I wondered if reading the whole paper would help, but I was left with the impression that Grøn was serious when he indicated that it was an exercise in the understanding of GR, rather than a look at the twins.

Perhaps a combination of Richard Wolfson’s “…the straightest path for a free-float observer in spacetime is also the path on which the time between two events is the greatest”, and Michael Huemer’s insistence “…that there is no reference frame in which Space Twin is at rest throughout the story…” is all we really need, apart from a word of wisdom on #47 :).
 

Offline PmbPhy

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Re: How should one interpret spacetime diagrams?
« Reply #53 on: 05/04/2015 18:48:23 »
Quote from: jeffreyH
Could someone translate this into lay-speak, please?

Quote from: Bill S
I would like it worded better too. Is inertial dragging related to the dragging of inertial frames for instance? Or something entirely different? What is the Schwarzschild radius of the cosmic mass? Isn't that infinite by definition?

I sent the author your questions and he replied as follows
Quote
"Inertial dragging" is the same as "dragging of inertial frames".

I talk of the cosmic mass inside the horizon, and that is finite
I doubt that satisfies your question so perhaps you have a follow up.

You should go to my forum. I'll ask him to join and answer directly.
 

Offline jeffreyH

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Re: How should one interpret spacetime diagrams?
« Reply #54 on: 05/04/2015 20:04:04 »
Quote from: jeffreyH
Could someone translate this into lay-speak, please?

Quote from: Bill S
I would like it worded better too. Is inertial dragging related to the dragging of inertial frames for instance? Or something entirely different? What is the Schwarzschild radius of the cosmic mass? Isn't that infinite by definition?

I sent the author your questions and he replied as follows
Quote
"Inertial dragging" is the same as "dragging of inertial frames".

I talk of the cosmic mass inside the horizon, and that is finite
I doubt that satisfies your question so perhaps you have a follow up.

You should go to my forum. I'll ask him to join and answer directly.

That answers my questions Pete. I don't want to bug the author so I am happy with what he says.
 

Offline Colin2B

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Re: How should one interpret spacetime diagrams?
« Reply #55 on: 30/06/2015 06:56:50 »
Everything does exist at the same time under present-dynamism only. 
You should post this under New Theories. Either copy it there or ask one of the moderators to move it for you.
 

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Re: How should one interpret spacetime diagrams?
« Reply #55 on: 30/06/2015 06:56:50 »

 

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