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New derivation of pi links quantum physics and pure math
phys.org ^ | November 10, 2015 | Provided by: American Institute of Physics

Posted on 11/10/2015 10:54:08 AM PST by Red Badger

Two pages from the book "Arithmetica Infinitorum," by John Wallis. In the table on the left page, the square that appears repeatedly denotes 4/pi, or the ratio of the area of a square to the area of the circumscribed circle. Wallis used the table to obtain the inequalities shown at the top of the page on the right that led to his formula. Credit: Digitized by Google

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In 1655 the English mathematician John Wallis published a book in which he derived a formula for pi as the product of an infinite series of ratios. Now researchers from the University of Rochester, in a surprise discovery, have found the same formula in quantum mechanical calculations of the energy levels of a hydrogen atom.

"We weren't looking for the Wallis formula for pi. It just fell into our laps," said Carl Hagen, a particle physicist at the University of Rochester. Having noticed an intriguing trend in the solutions to a problem set he had developed for students in a class on quantum mechanics, Hagen recruited mathematician Tamar Friedmann and they realized this trend was in fact a manifestation of the Wallis formula for pi.

"It was a complete surprise - I jumped up and down when we got the Wallis formula out of equations for the hydrogen atom," said Friedmann. "The special thing is that it brings out a beautiful connection between physics and math. I find it fascinating that a purely mathematical formula from the 17th century characterizes a physical system that was discovered 300 years later."

The researchers report their findings in the Journal of Mathematical Physics.

In quantum mechanics, a technique called the variational approach can be used to approximate the energy states of quantum systems, like molecules, that can't be solved exactly. Hagen was teaching the technique to his students when he decided to apply it to a real-world object: the hydrogen atom. The hydrogen atom is actually one of the rare quantum mechanical systems whose energy levels can be solved exactly, but by applying the variational approach and then comparing the result to the exact solution, students could calculate the error in the approximation.

Figure 1: Calculations derived by Tamar Friedmann and Carl Hagen resulted in an expression of special mathematical functions called gamma functions. Credit: Tamar Friedmann and Carl Hagen/University of Rochester

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When Hagen started solving the problem himself, he immediately noticed a trend. The error of the variational approach was about 15 percent for the ground state of hydrogen, 10 percent for the first excited state, and kept getting smaller as the excited states grew larger. This was unusual, since the variational approach normally only gives good approximations for the lowest energy levels.

Hagen recruited Friedmann to take a look at what would happen with increasing energy. They found that the limit of the variational solution approaches the model of hydrogen developed by physicist Niels Bohr in the early 20th century, which depicts the orbits of the electron as perfectly circular. This would be expected from Bohr's correspondence principle, which states that for large radius orbits, the behavior of quantum systems can be described by classical physics.

"At the lower energy orbits, the path of the electron is fuzzy and spread out," Hagen explained. "At more excited states, the orbits become more sharply defined and the uncertainty in the radius decreases."

Figure 2: The classic 18th century Wallis formula defining pi. Credit: University of Rochester

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From the formula for the limit of the variational solution as the energy increased, Hagen and Friedmann were able to pull out the Wallis formula for pi.

The theory of quantum mechanics dates back to the early 20th century and the Wallis formula has been around for hundreds of years, but the connection between the two had remained hidden until now.

"Nature had kept this secret for the last 80 years," Friedmann said. "I'm glad we revealed it."

More information: "Quantum mechanical derivation of the Wallis formula for pi," by Tamar Friedmann and C.R. Hagen, Journal of Mathematical Physics , November 10, 2015. DOI: 10.1063/1.4930800 , http://scitation.aip.org/content/aip/journal/jmp/56/11/10.1063/1.4930800


TOPICS: Astronomy; Education; History; Science
KEYWORDS: mathematics; pi; quantumtheory
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To: aquila48

“They found that the limit of the variational solution approaches the model of hydrogen developed by physicist Niels Bohr in the early 20th century, which depicts the orbits of the electron as perfectly circular.”

Yeah - when I hit that line in the article I thought “Well duh - pi is going to get involved.”

Still though - cool article. I think it might be more an article on the link between classical and quantum physics than anything else.


21 posted on 11/10/2015 12:44:20 PM PST by 21twelve (http://www.freerepublic.com/focus/f-news/2185147/posts It is happening again.)
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To: Freedom_Is_Not_Free
I love math and physics and what they mean and describe and reveal. I just wish I had the brain of a genius to truly understand it. These higher math principals give me fits. Can’t get my brain around them. Calculus was bad enough. Thank goodness there are true geniuses out there who can discover and process the math and physics of the universe. It is fascinating. Just wish I truly deeply understood it.

Ditto. Higher math is all relationships, variables, proportions, feedback loops, even shapes. Very few numbers, and where they exist, they're moving...

22 posted on 11/10/2015 12:54:31 PM PST by Talisker (One who commands, must obey.)
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To: Red Badger
Very interesting.
BFL to share
23 posted on 11/10/2015 1:02:25 PM PST by zeugma (Teach your child a love for motorcycles, and he'll never have money for drugs.)
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To: ifinnegan

Those same people claim it’s all just one big accident............................


24 posted on 11/10/2015 1:04:29 PM PST by Red Badger (READ MY LIPS: NO MORE BUSHES!...............)
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To: Red Badger

Just imagine what will be figured out in eternity. oh, that’s right, all knowledge will cease. New rules! start over. At least I won’t have to worry about getting dementia.


25 posted on 11/10/2015 1:09:41 PM PST by huldah1776
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To: Attention Surplus Disorder

Plenty of research is going on for that newly discovered subatomic particle, the moron. It’s found only in buffoonium.


Which is the base element of the Democrat Party


26 posted on 11/10/2015 1:13:26 PM PST by Rumplemeyer (The GOP should stand its ground - and fix Bayonets)
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To: huldah1776

It’s a BIG UNIVERSE out there!
You’ll be able to go from one end to the other in the blink of an eye!.....................................


27 posted on 11/10/2015 1:13:32 PM PST by Red Badger (READ MY LIPS: NO MORE BUSHES!...............)
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To: piytar
Here is one use of pi, e (another transcendental number, namely the base of the natural logarithm aka Euler’s number) and i (the square root of -1) that I still find to be incredible: e^(i*pi) = -1

Yeah, contemplating that one... makes you believe in The Force.


28 posted on 11/10/2015 1:15:21 PM PST by Talisker (One who commands, must obey.)
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To: Red Badger

Serious question. Since Philip was transported, Jesus also went to the other side of the lake and walked on water, do you think when Jesus reigns, that will be understood and permissible before the new heaven/earth?


29 posted on 11/10/2015 1:32:04 PM PST by huldah1776
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To: huldah1776

During the Thousand Year Reign for some, everybody thereafter..................


30 posted on 11/10/2015 2:12:31 PM PST by Red Badger (READ MY LIPS: NO MORE BUSHES!...............)
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To: Red Badger; Ezekiel
Pi, in the beginning, of the TORAH

Bereshis 1 (Genesis) 1 In the beginning ELoHIM created hashomayim (the heavens, Himel) and haaretz (the earth).

ELoHIM, Alef Lamed Hei Yud Mem, Hebrew read right to left

אֱלֹהִים

Gematria of, 1, 30, 5, 10. 40 (no final mem value here)

Drop the 0‘s put the numbers in a circle (so to speak) and you get 31415

Ergo: ELoHIM is infinite!

How about the Brit Chadashah (New Covenant)

Luke 12:27 “Consider the lilies how they grow: they toil not, they spin not; and yet I say unto you, that Solomon in all his glory was not arrayed like one of these.”

Turns out a lily has about 100 times more DNA than a human! Arrayed indeed!

And to borrow a phrase from Monty Python...

Well you have to know these things when you're a King you know.

There's lot's more (folding space in Tehillim) but I'm busy trying to hack into dark energy. Moses did! Anthony Quinn, Lawrence of Arabia

31 posted on 11/10/2015 7:21:33 PM PST by Jeremiah Jr (EL CHaI)
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To: Jeremiah Jr

ELoHIM is infinite!..............and beyond!................(sorry, I just couldn’t help myself!)


32 posted on 11/11/2015 7:06:30 AM PST by Red Badger (READ MY LIPS: NO MORE BUSHES!...............)
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To: Red Badger

God does not play dice with the universe.

But He does play games...


33 posted on 11/11/2015 7:09:36 AM PST by Fresh Wind (Falcon 105)
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To: Fresh Wind

...and He has a great sense of humor and irony!...........................


34 posted on 11/11/2015 8:32:33 AM PST by Red Badger (READ MY LIPS: NO MORE BUSHES!...............)
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To: Red Badger; Ezekiel
From the movie Pi Faith in Chaos

Pi (Math is everywhere)

https://www.youtube.com/watch?v=WFmWhwyA0NU

The Torah is a long string of numbers...

35 posted on 11/11/2015 8:51:08 PM PST by Jeremiah Jr (EL CHaI)
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