Is it possible to measure Hausdorff dimension for real world objects?

In summary, measuring the Hausdorff dimension of real world objects such as the surface of the brain or broccoli is not possible in a strict sense. While the Hausdorff dimension can be approximated using methods like box counting, it is difficult to measure precisely due to the imperfections and irregularities of these objects. Additionally, measurements of irregular pieces of broccoli can be affected by sources of error such as averaging axes and accurately splitting the broccoli. These challenges are highlighted in the Hypertextbook's experiment of measuring the diameter of broccoli.
  • #1
sceptic
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0
Is it possible practically to measure Hausdorff dimension of the surface of the Brain or the broccoli? For a broccoli Hausdorff dimension is equivalent to the so called box counting dimension, which is far more practical? I think, following the original definition Hausdorff dimension it is quite difficult to measure it directly. There are some theorems which can guarantee that some kind of simple procedure can produce the same result?
 
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  • #2
First, what do you mean by "real world object" and, second, what do you mean by "measure"? Would you consider a cube a "real world object"? That would be easy- its "Hausdorff measure" is just its volume, height times width times depth. If you mean that as a "real world object" even a "cube" would have imperfections, ridges, etc., like a "brain" or "cauliflower" then the best you can do is approximate it- just as the best you can do with a "real world" line segment is approximate its length because it does not have exactly-defined end points.
 
  • #3
No, strictly speaking, it is not possible. Fractal dimensions of natural phenomena are largely heuristic and cannot be regarded rigorously as a Hausdorff dimension. (From the Wikipedia, 'Hausdorff Dimension')

"Sources of Error

It was difficult to measure the diameter of irregular pieces. We were forced to average the major and minor axes.
It was very difficult to determine where to split the broccoli as the size became smaller.
It was ever more difficult to accurately split it, some of the buds shed off when it was being handled."

http://hypertextbook.com/facts/2002/broccoli.shtml

(I am frequently amazed by the influence of Glenn Elert's Hypertextbook, not least for guiding my selection of a recumbent bicycle for 50K miles of touring.)
 

1. Can Hausdorff dimension be measured for all real world objects?

No, Hausdorff dimension can only be measured for certain types of objects that have a fractal or self-similar structure. Everyday objects such as chairs, tables, or buildings do not have a fractal structure and thus cannot have a Hausdorff dimension.

2. How is Hausdorff dimension different from Euclidean dimension?

Hausdorff dimension is a measure of the complexity or irregularity of a geometric object, while Euclidean dimension is a measure of the space needed to contain the object. For example, a line and a circle both have a Euclidean dimension of 1, but a line has a Hausdorff dimension of 1 while a circle has a Hausdorff dimension of 1.3.

3. What is the process for measuring Hausdorff dimension?

The process for measuring Hausdorff dimension involves dividing the object into smaller and smaller parts and calculating the ratio of the length/area/volume of each part to the length/area/volume of the entire object. This ratio is then raised to a power, and the Hausdorff dimension is the value of that power that makes the ratio converge to a non-zero number.

4. Is Hausdorff dimension a discrete or continuous value?

Hausdorff dimension is a continuous value, meaning it can take on any non-negative real number. This is because the Hausdorff dimension is based on the concept of self-similarity, which is a continuous property.

5. Can Hausdorff dimension be measured for non-geometric objects?

Yes, Hausdorff dimension can also be measured for abstract objects such as mathematical sets, time series, and fractal patterns. In these cases, the process for measuring Hausdorff dimension may be different, but the concept of self-similarity still applies.

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