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Alpha Decay as Quantum Tunneling

We're covering tunneling in my quantum mechanics class. I did a little bit of research and was surprised to find out that Gurney and Condon made one of the first practical application of quantum tunneling to accurately predict alpha decay of various radioactive elements. They describe alpha decay as alpha particles tunneling through the attractive potential barrier of the nucleus. I found three very interesting journal articles on the subject. The first is a historical summary by Condon. The second and third are the initial journal articles by Gurney and Condon in Nature and Physical Review. All three of these articles can be accessed for free from most university libraries. EU Condon, Tunneling - How it all Started, Am. J. Phys., 46, 319, (1978) Gurney and Condon, Wave Mechanics and Radioactive Disintegration, Nature, 122, 439, (1928) Gurney and Condon, Quantum Mechanics and Radioactive Disintegration, Phys. Rev., 33, 127, (1929)

Luna Moth on Long Island

This little, (kinda big actually), guy was hanging out at the gas station today.

Boulder in Scarecrow and Mrs. King!

Why is Boulder, CO cast in the part of Washington D.C. in Scarecrow and Mrs. King, Season 3, Episode 19, "The Boy Who Could Be King"? 11:32 into the episode a panning shot that is supposed to be in downtown DC is actually the Pearl St. mall, in Boulder, CO. Here's the shot from the episode, (scroll down for the same view of the Pearl St. mall in Google Earth): Here's the view of the Pearl St. mall in Google Earth. Google Earth is a bit strange, you may have to reload the page to get the correct picture, (or click the 'View Larger Map' link below: View Larger Map Later at 23:14 an assay report is shown from the Stagler Mining Co. of Bolder Colorado. Anybody know if there was any rhyme or reason to all this?

It's Obvious... Not: Knowing When not to do the Math

I'm still studying for quals. I got stuck for awhile on problem 2.11 of Griffith's Introduction to Quantum Mechanics first edition. The problem involves manipulating raising and lowering operators to perform a normalization. The problem I was having was doing too much of the math too early. I tried to expand all the operators and got stuck. I tried to apply integration by parts as the book suggests and applied it to the wrong term the first time, and carried the operation too far on a second try. The series of conservative steps that finally did the trick is shown in the video below.

More on the Jeri Ellsworth SDR Videos

After seeing Jeri Ellsworth's videos on software defined radios, it looks like something that'd be fun to try. This post is just an easy access point for the reference materials I'm using. It starts with the Element14/Jeri Ellsworth video outlining her SDR project followed by her 7 vlog entries on the project. Following that are links to the FB papers on SDR from AC5OG, and a few references to parts from Sparkfun that look like they'd be handy. vlog part 1 vlog part 2 vlog part 3 vlog part 4 vlog part 5 vlog part 6 vlog part 7 AC5OG SDR Paper part 1 AC5OG SDR Paper part 2 AC5OG SDR Paper part 3 AC5OG SDR Paper part 4 Sparkfun analog mux board Winrad software from I2PHD

Satellite Tracking adds Bearings

The satellite tracking tool now displays the bearing from your location to the first and last visible points on each satellite pass as well as the bearing of the maximum elevation. For elevation, the number in the upper row is the number of degrees above the horizon, and the number in the lower row is the bearing.

Geometry, Trigonometry, and Amateur Satellites

Back to Part III . I'm still playing around with building a satellite tracking application. I'm helping with a special event station to help raise awareness for the Friends of Science East's effort to restore Tesla's last lab, Wardenclyffe, in Shoreham, NY . First, the good news, the satellite pass finder and viewer is up and running at http://copaseticflows.appspot.com/findsat ! Just drag the yellow thumbtack to your location and click the 'Passes' button and all the radio visible satellite passes for your location will be listed. By clicking on the map checkbox for any pass, you can display it on the globe. You can see how visible a pass will be from a city building by positioning yourself near the building and looking up for the pass. The app is still very beta, so please let me know if you see anything that could be better. One of the big steps in getting the application to work was determining if a satellite would be visible over the horizon. To do thi...