Interpretation of Flamm Paraboloid

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SUMMARY

The Flamm Paraboloid, derived from the Schwarzschild Metric, describes the curvature of space around a gravitating mass with the equation w(r) = 2 √(r_s (r - r_s)). Unlike the Newtonian model of gravitational potential wells, which decrease inwards, the Flamm Paraboloid increases outwards. This indicates that mass does not simply bend spacetime "downwards" but can be interpreted as bending it "upwards," as illustrated by the analogy of a bent blade of grass. The key takeaway is that the spatial curvature represented by the Flamm Paraboloid is crucial for understanding gravitational effects, regardless of the visual representation.

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  • Understanding of the Schwarzschild Metric
  • Familiarity with the concept of gravitational potential wells
  • Basic knowledge of general relativity
  • Ability to interpret mathematical equations related to curvature
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  • Explore the implications of the Schwarzschild Metric in general relativity
  • Study the mathematical properties of the Flamm Paraboloid
  • Investigate the differences between spatial and spacetime curvature
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Widdekind
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In the Schwarzschild Metric, the curvature of space around the gravitating mass can be described by the Flamm Paraboloid:
w(r) = 2 \sqrt{r_{s} (r - r_{s})}​
Unlike the Newtonian depiction of Gravitational Potential Wells (U = - G M / r) which decrease inwards, the Flamm Paraboloid increases outwards.

QUESTION: Does this mean, that rather than mass "bending the fabric of Spacetime 'downwards'" -- a la the "Rubber Sheet" analogy -- that mass actually bends the fabric of Spacetime about it "upwards" ?

ANALOGY: Take a long blade of grass. It's straight representing a flat 1D "Lineland" space. Now, bend the blade of grass at some spot in the middle. That represents the curving of space caused by a massive body, "at the point of bend". But, the result is not so much that the "point of bend" bends downwards, but that both tips of the blade of grass bend upwards.

Can this be construed as an accurate interpretation of the Flamm Paraboloid ? Perhaps, if you "embed" a roughly Schwarzschild-esque solution, for a star (say), in a larger Cosmological fabric of Spacetime, then those "tips of the blade of grass" are "anchored" into that larger fabric, so that when the star tries to bend those tips upward, it actually "pushes itself downwards" ??

I have tried to illustrate my questions w/ the attached figure below:
 

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Widdekind said:
QUESTION: Does this mean, that rather than mass "bending the fabric of Spacetime 'downwards'" -- a la the "Rubber Sheet" analogy -- that mass actually bends the fabric of Spacetime about it "upwards" ?
Flamm's paraboloid only represents the spatial curvature not the space-time curvature.
http://www.physics.ucla.edu/demoweb..._and_general_relativity/curved_spacetime.html

It doesn't matter if you visualize it downwards or upwards. What matters are the distances within the 2D paraboloid surface, which are greater near the mass than further away. The 3rd dimension of the pictures is irrelevant for someone living within the 2D paraboloid surface which represents our 3D space.
http://en.wikipedia.org/wiki/Gravity_well#Gravity_wells_and_general_relativity
 
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