Can a vacuum have a speed?

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Re: Can a vacuum have a speed?

Postby BurtJordaan on March 12th, 2017, 11:33 am 

Dave_Oblad » 12 Mar 2017, 16:23 wrote:Anyway, GPS is off Topic.. so best not go there from here.

Hi Dave, so why not rather discuss the topic then? Obviously with the proviso that you stay off your private theory as well...
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Re: Can a vacuum have a speed?

Postby Dave_Oblad on March 13th, 2017, 9:16 am 

Hi all,

Agreed, as long as some folks don't drop deliberate slurs targeting me.. no problem. So back on target again.

I agree that Space can't have a Speed relative to itself, no more than I can have a Speed relative to Myself.

I had posited the question if Expansion can be included in the the actual observations that remote locations in space do, in fact, have their own Unique Velocities. The Doppler evidence of remote Galaxies, that are intrinsically bound by their local Space-Time neighborhoods, do prove that Space can have differential velocities over large enough distances. That's based on pure observation and can't be disputed.

What might be disputed is if a good reason, such as Expansion, can be used to disqualify our observations.

If a rocket can push a Spaceship away from me and that qualifies as a solid reason for a Velocity differential between Me and said Spaceship.. and given that Science currently explains Expansion is the result of Dark Energy Pressure, then perhaps we shouldn't be too quick to disqualify Expansion as a good reason for our observations that Space is being observed as having unique Private Differential Velocities or independent Speeds.. as the case may be.

I'm not convinced that supplying an explanation (Dark Energy or Hubble Constant) for our Real Observations is any different than supplying an explanation for why a rocket accelerates by burning fuel.

Basically: Can an Explanation disqualify an Observation?

The OP is <NOT> asking "why" a Volume of Vacuum can have its own unique speed but rather have we ever observed such to be true. If we base our answer on observations of the Universe only.. then the answer must be "Yes".. a Volume of Vacuum can have its own unique Speed relative to other Volumes of Vacuum. The further the faster and visa-versa.

Just because those Speed Differentials follow some specific Constant relative to Distance doesn't disqualify the Cosmic Observation that we do witness Unique Speed Differentials (regarding Space-Time or vacuum) in the Observable Universe.

Perhaps.. if we could prove that Remote Galaxies are in fact moving at near the Speed of Light independent of their local Space-Time neighborhoods.. then perhaps a case can be made to answer the OP with a resounding "NO".

But honestly, this latter idea is not the side I would want to support.

Best Regards,
Dave :^)
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Re: Can a vacuum have a speed?

Postby vivian maxine on March 13th, 2017, 9:42 am 

Q. Is it space/vacuum that have speed? Or is it the objects that are moving through space and/or vacuum that have the speed? I don't see how space can have speed. Is space moving?
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Re: Can a vacuum have a speed?

Postby Dave_Oblad on March 13th, 2017, 10:21 am 

Hi Vivian,

Jorrie is the Expert and even has a calculator on the net that will calculate how fast a remote location in Space will be moving away from us based on the absolute Distance from us.

Since distances vary, then of course, for each distance you apply relative to us.. you will get a different Speed. Said Speed will increase by a constant amount.. by the increased absolute distance you feed into the Calculator.

Said location relative to us is a location in Space and not an arbitrary Galaxy.. as each Galaxy can have its own Speed Relative to its own neighborhood. But that speed is very minor compared to Expansion in general, especially over really large distances.

But I will defer to Jorrie's Expertise. I'm terrible at Math...lol.

Also, I am assuming Jorrie's calculator can supply said information as described above.. as I have never actually seen his Calculator.. but I hear it's Great.

Regards,
Dave :^)
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Re: Can a vacuum have a speed?

Postby BurtJordaan on March 13th, 2017, 10:41 am 

Dave_Oblad » 13 Mar 2017, 15:16 wrote:The OP is <NOT> asking "why" a Volume of Vacuum can have its own unique speed but rather have we ever observed such to be true.

To which the answer is no. We can infer the radial speed of astronomical things in our own cluster of galaxies from the red- or blue-shifts that we observe. How do you propose we should go about observing the speed of space inside the cluster? I think it is impossible.

Recall that I do not want to digress further into cosmology here; if required, please start a new thread under the Astro/Cosmo sub-forum.
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Re: Can a vacuum have a speed?

Postby BurtJordaan on March 13th, 2017, 10:52 am 

Hi Dave, not that I want to discuss the calculator(s) here, but lately I have 2 on the web:

A simpler one: Cosmological Calculator, Feb 2013 and the "latest, greatest, all singing, all dancing": LightCone 7. ;)
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Re: Can a vacuum have a speed?

Postby Dave_Oblad on March 13th, 2017, 1:41 pm 

Hi Jorrie,

You are right. I reread this whole thread and ralfcis did in fact.. clarify his question to focus on Local Space which makes it an SR question rather than a Cosmological question.

Regards,
Dave :^)
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