Quantum Mechanics 10 Dimensions
Sometimes there are posts in this cosmology group about string theory and the number of proposed dimensions. That number ranges from 10, 11, 26, and more. These articles and headlines about string theory should say concepts not dimensions. As an engineer a dimension is a numeric measurement or value. Some of these 10 dimensions are just concepts with no numeric value. They are just place holders for something (a concept) that cannot be a number.
Here are the 10 socalled dimensions: 1) length 2) height 3) depth 4) time 5 ) possible worlds but different than ours  not a dimension 6 ) all possible worlds with the same start conditions  not a dimension 7 ) all possible worlds with different start conditions  not a dimension 8 ) all possible worlds with different start conditions branching out to infinity not a dimension 9 ) all possible worlds with all possible start conditions and it has the laws of physics  not a dimension 10) infinite possibilties not a dimension
There is no clear definition for the concepts: world, start condition, or possibilities. Having learned a few things in high school and college I can confidently say calling these concepts a set of 10 dimensions is nonsense. The frequent use of 'all' and a quantity of 'infinite' are signs of only a theory not something that can be tested with the scientific method. superstring theory with these 10 vague dimensions is relevant only to those pursuing the definition of a coherent theory which is obviously still in progress. In science a theory must be both testable and repeatable. With these defined dimensions a repeatable test is impossible (infinite tests!!?)
From wikipedia: ' In order to describe real physical phenomena using string theory, one must therefore imagine scenarios in which these extra dimensions would not be observed in experiments.'
Therefore the theory defines dimensions (that are imagined) but they are ignored during an actual test. The scientific method involves testing the theory to confirm or deny its assumptions and predictions but a significant part just gets ignored for a test. I suppose I need to read learn more about string theory to check its progress but just an overview of the defined dimensions is not promising.
I posted a followup
About 5 hours ago I posted about these 10 dimensions (described in the video). Only the first 3 are actually dimensions, having a numeric value. The rest after 4 are just theoretical concepts and cannot take a numeric value like a dimension. I must be too cynical to suggest string theory uses the term dimension only because that will make string theory appear similar to 3 or 4 dimensional theories. At this point that intended impression is false as string theory cannot even test any of its claimed dimensions beyond the first 3 or 4.
Hit back to go to previous page in history. Select Cosmology to see other posts and comments to that group.
