Can Mass be Converted to Volume without Gravity?

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Discussion Overview

The discussion centers around the conversion of mass to volume in the context of negligible gravitational effects. Participants explore the relationship between mass, volume, and density, while also delving into concepts related to Planck units and the implications of scaling these units for convenience in calculations.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • Some participants inquire about the equation for converting mass to volume, emphasizing that density is the key relationship, which varies by substance.
  • One participant expresses interest in scaling Planck units for convenience, suggesting a hypothetical scenario where 1 Planck volume equals 1 cubic meter.
  • Another participant corrects the misunderstanding that a Planck volume is equivalent to 1 m³, clarifying it is approximately 4 × 10-105 m³.
  • There is a discussion about the implications of using different constants (like h-bar) and how they relate to gravitational and speed of light units, raising questions about normalization.
  • Participants mention the complexity of converting mass to volume while factoring in density for rest mass energy, and the desire to plot relationships between volume, mass, and valency against specific gravity.
  • One participant notes that density is a macro phenomenon dependent on atomic arrangement, suggesting that a single density for an element may not exist, which complicates the proposed analysis.
  • There are references to classical and electromagnetic radii as potential reference points, as well as a mention of a scale invariant quantum Hall impedance.
  • A later reply introduces a concept about magnetic monopoles and their detection, though it is noted as a deviation from the main topic.

Areas of Agreement / Disagreement

Participants express varying degrees of understanding and agreement on the concepts discussed, but no consensus is reached on the feasibility of converting mass to volume under the specified conditions or the implications of the proposed scaling of Planck units.

Contextual Notes

The discussion reveals limitations in understanding the relationships between mass, volume, and density, particularly in the context of quantum mechanics and the implications of scaling units. There are unresolved mathematical steps and assumptions regarding the nature of density and its dependence on atomic structure.

hubble_bubble
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Is there an equation to convert mass to volume assuming a negligible gravitational effect. So say 1 micro gram occupies a particular volume.
 
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The relationship between mass and volume is called the Density (look it up). Density varies from substance to substance. Gravity doesn't come into it unless you are dealing with a substance that is compressible under its own weight (say air).
 
sophiecentaur said:
The relationship between mass and volume is called the Density (look it up). Density varies from substance to substance. Gravity doesn't come into it unless you are dealing with a substance that is compressible under its own weight (say air).

OK. I am trying to understand the relationships between Planck length, Planck mass and Planck volume. The measurements are so small and have a standard uncertainty I was thinking I could scale them up somehow to say make 1 Plank volume equal to 1 cubic metre for convenience and then derive the other units from that. Don't ask me why I want to do this as it is something I am working on that is not related to current theories and would cause problems if I discussed it here.
 
Scaling numbers up can easily be done by using scientific notation.
 
hubble_bubble said:
... I was thinking I could scale them up somehow to say make 1 Plank volume equal to 1 cubic metre for convenience and then derive the other units from that.
But a Planck volume is not 1 m3, it is (1 Planck length)3, or about 4 × 10-105 m3.

(If I understand your statement correctly.)
 
I think the idea was to divide it by 4x10-105 to make it easier to work with.
 
russ_watters said:
I think the idea was to divide it by 4x10-105 to make it easier to work with.

The problem is with h-bar if I have h at 1. If I have 1/2pi for h-bar then how would this relate to G and c? The units are no longer normalised, are they?
 
You aren't really explaining what you are trying to do, so I have no idea what the issue is. Perhaps you need to be working with the equations without plugging in the values?
 
russ_watters said:
You aren't really explaining what you are trying to do, so I have no idea what the issue is. Perhaps you need to be working with the equations without plugging in the values?

I think that is what I will have to do otherwise I am comparing apples with pears. Ultimately I want to convert mass to a volume. I need to factor in a density for a rest mass energy. I want to plot volume and mass for various elements at rest mass. Unless this has already been done. I also want to plot valency against specific gravity for elements in the periodic table. Does anyone know if this has been done somewhere.
 
  • #10
Yes, if you don't want to deal with ugly values, working with equations can avoid that.

And yes, you can certainly find tables of densities online. However, be aware that density is a macro phenomenon that depends on the arrangement of the atoms. There is not one single density for an element. This probably means that what you are seeking to do isn't possible.
 
  • #11
russ_watters said:
Yes, if you don't want to deal with ugly values, working with equations can avoid that.

That's what I am thinking.

russ_watters said:
And yes, you can certainly find tables of densities online. However, be aware that density is a macro phenomenon that depends on the arrangement of the atoms. There is not one single density for an element. This probably means that what you are seeking to do isn't possible.

I know and that is going to be a real problem. I haven't worked out how to resolve it yet. I am sure there will be a way but the math will be complex. Maybe too complex.
 
  • #12
I have been reading up on the classical electron radius. If I were to use this as a reference point and sidestep quantum mechanics (I know!) then this could give me some reference point.
 
  • #13
This then leads on to the electromagnetic radius for any mass.
 
  • #14
Has anyone heard of the scale invariant quantum Hall impedance.

I found this.

[crackpot link deleted]
 
Last edited by a moderator:
  • #15
The article above seems to indicate that one of the magnetic monopoles is reacting out of range of detection. This may mean that the photon is actually too big for us to detect in its entirety.
 
  • #16
Since the OP is hijacking his own thread, it's a good time to stop.
 

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