How many cubic planck lengths are in the observable universe?

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The discussion centers on calculating the number of cubic Planck lengths that can fit within the observable universe, emphasizing that the calculation involves dividing the volume of the universe by the volume of a Planck unit cube. Participants note that while strings are theoretically smaller than Planck lengths, they complicate the question since they do not have a defined size. The approximate calculation yields around 9.47 x 10^184 cubic Planck lengths in the observable universe. The conversation highlights the importance of understanding the volume measurements and the theoretical nature of strings in relation to Planck lengths. Overall, the focus remains on the mathematical approach to estimating the volume of the universe in terms of Planck units.
Alex299792458
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If you take the size of the observable universe can you find out how many cubic plank lengths can fit in the observable universe and it doesn't have to be exact just approximation.Also the math and formulas would be helpful too.
 
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Err... is there anything more to this than "volume of universe divided by volume of Planck unit cube"?
 
Technically the amount of strings in the universe would be greater but the amount of strings in the universe in unnecessary and meaningless because most of space is empty(there are virtual particles, gravitational field, electromagnetic fields etc. but it doesn't occupy any real space and those things are for another forum) and strings don't have a definite size and by that I mean a plank length is 1.61619926 × 10^-35 meters and you can't say a string is exactly this small because plank length is a unit of measurement and a string is a theoretical object.
 
I'm not sure I follow how strings fit into the OP question, which is just a "how many things of volume X fit into volume Y" question.
 
Because, strings are smaller than cubic plank lengths so, if you use strings to find out how many of them fit in the universe it would be more than cubic plank lengths and as you said "volume of universe divided by volume of Planck unit cube" which is what I am asking about and if you then do "volume of universe divided by the volume of a string" which would be greater than your original statement in turn answering your question.
 
Because, since strings are smaller than a cubic plank length you can fit more them in a volume so, in your original statement "volume of universe divided by volume of Planck unit cube" (which is what I am asking about) would be let's say "ƒ" and if you that the "volume of the universe divided by volume of a string" would be greater than "ƒ" and let's call it "β" so β>ƒ. Which answers your statement and in turn answers your question.
 
Alex299792458 said:
If you take the size of the observable universe can you find out how many cubic plank lengths can fit in the observable universe and it doesn't have to be exact just approximation.Also the math and formulas would be helpful too.

Google will tell you what the volume of the observable universe is and what the Planck length is. That's should be enough to allow you to calculate the value that you're looking for.
 
Thank you so much! I work out that there should be 9.47491416160062548455633952329712e+184 or 9474914161600625484556339523297120000000000000000000-00000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 cubic plank lengths in the observable universe!
 
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