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Lunct
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The definition of the Planck length I have found is that it is the shortest length that has meaning. What is meant by that? Can someone give be a better definition of what it is?
There's a lot of misleading stuff written about the Planck length, and definition you've found is an example. Give this Insights article a try: https://www.physicsforums.com/insights/hand-wavy-discussion-planck-length/Lunct said:The definition of the Planck length I have found is that it is the shortest length that has meaning. What is meant by that? Can someone give be a better definition of what it is?
So does quantum theory only apply to things smaller than the Planck length? That cannot be right.Nugatory said:There's a lot of misleading stuff written about the Planck length, and definition you've found is an example. Give this Insights article a try: https://www.physicsforums.com/insights/hand-wavy-discussion-planck-length/
You're right, it's not right.Lunct said:So does quantum theory only apply to things smaller than the Planck length? That cannot be right.
Thanks for the help.Nugatory said:You're right, it's not right.
The Planck length is the approximate distance at which quantum gravity starts to matter. Quantum mechanics has not been completely and successfully integrated with gravity, but works just fine above the Planck length, where we don't need a theory of quantum gravity.
Your right, but what I am saying is the LQG has more testable proof. Also Occam's Razor suggests LQG as it is much more simple than having the 11 plus dimensions.FactChecker said:Theories can be supported or can survive a test, but that is not the same as being totally proven. If string theory can not be proven or disproved, that is good enough. It means that it is consistent with reality.
Good points. Simpler is better. And if it is stronger and allows some testable predictions that string theory does not, then that is better (assuming that it passes the tests). Simpler and stronger together are much better.Lunct said:Your right, but what I am saying is the LQG has more testable proof. Also Occam's Razor suggests LQG as it is much more simple than having the 11 plus dimensions.
thanks for the repliesFactChecker said:Good points. Simpler is better. And if it is stronger and allows some testable predictions that string theory does not, then that is better (assuming that it passes the tests). Simpler and stronger together are much better.
The Planck length is the smallest unit of length that has any physical meaning in the universe. It is approximately 1.616 x 10^-35 meters and is important because it is believed to be the scale at which quantum effects become significant and our current understanding of physics breaks down.
The Planck length was first introduced by physicist Max Planck in 1899 as a fundamental unit of length based on fundamental constants such as the speed of light, the gravitational constant, and Planck's constant. It was later derived from the theory of general relativity and quantum mechanics.
Due to its incredibly small size and the limitations of current technology, the Planck length cannot be directly measured. It is a theoretical concept used in theoretical physics and is not currently accessible by any experimental means.
The Planck length is much smaller than any other unit of length, including the nanometer and the atomic scale. It is also much larger than the string length and the Planck time, which are other fundamental units in theoretical physics.
The Planck length is still a topic of ongoing research and debate in theoretical physics. It is believed that at this scale, the fundamental forces of nature are unified and a better understanding of the universe may be gained. However, there is currently no concrete evidence or consensus on what secrets the Planck length may hold.