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Pirates and Axions

Nowadays elementary particle people can be compared with pirates. All of them are searching for some treasure (aka particle, new physics… ). Many of them claim top have some map, but certainly not written by those who have buried the treasure. Whatsoever, because the world is quite simple , one-dimensional (energy), there are guys who climb the hills to search places nobody has seen so far.

But yesterday in the gauge theory seminar we had a talk of Andreas Ringwald, who belongs to the other species of pirates, which don’t care about maps. He s one of the guys who dig deep, hoping for some unexpected find.

To abandon the annoying image: Ringwald scans the low energy regime (sub eV) to find some evidence of new particles, axions or ALPs (axion like particles). Axions are weak coupling neutral particles which can be produced by high energetic photons and decay into photons if they are exposed to a strong magnetic field.

And what he did has drawn some attention, because he used a rejected HERA magnet for his experiments and a few years ago some italians said they saw something (they dismissed it later). He even was mentioned by the german press .

But a bunch of new experiments will dig deeper and Ringwald puts a lot of enthusiasm into this idea. For example one of his experiments measures “light shining through a wall”: you shoot a laser beam through a magnetic field, possibly creating axions. After that you place a wall. It should not affect the axions, but the light. Then, again, a strong magnetic field to give them the chance to decay into photons, which could be measured.

And, if it works, he will try to make it even bigger and build a radio, sending through the earth.

The beauty of physics

“Every time you see a beautiful woman, just remember, somebody got tired of her”

-Anonymous

I just finished reading “Some time with Feynman” by Leonard Mlodinow. Its not outstanding -if you expect a lot of time with Feynman- but thats not the point here. A part of it deals with the “friendship” between Gell-Mann and Feynman, who shared a corridor back than at Calltech.

Gell-Mann uses mathematical concepts to trace physics. You can tell from the few passages dedicated to him that his idea of pleasing physical theories are connected to a spotless mathematical background. I guess most of us share this feeling. At the time Gell-Mann was the mentor of a young guy named John Schwarz who worked on a crazy new idea called string theory. Little to nothing was speaking for that theory except for mathematical beauty. Arguably that has changed by now (not that I knew), but the evolution of string theory tells us that many of us are attracted by mathematical elegance , even if its the only argument (otherwise…why the hell wouldn’t it be refused in the beginning? ).

Feynman did refuse it. He is quoted by Mlodinow (not literally): ” The only thing this theory predicts are 10 dimensions. I can only see 4.” Feynman was special in the way that he couldn’t take much pleasure from ideas which depart from physical facts , whether they are (mathematical) beautiful or not. He even stated that it could be dangerous to treat physics with mathematical rigor , if the physical side lacks rigorous definitions from the start. That is, the physical in-put is not clear-cut (read the first chapter of Feynman Lectures on Gravitation). Maybe “beautiful” had another meaning to him and maybe thats an approach to successful physics.

Here is a great talk of Murray Gell-Mann at TED where he explains his concept of beauty. Its a very controversial point of view. Enjoy!