Hey Floyd,
I've only registered here yesterday and have my own issue with the girls, but I can totally understand you as I was once in similar shoes and I think I can share some thoughts.
Girls really like smart, knowledgeable guys, no doubt about that. Now go and make that work for you - one of the best ways in my opinion is to draw a sense of humor from it. Like you I'm also an extremely rational and logical person (nuclear physicist), which can cause more problems than solutions if you don't know how to behave (by for example expressing skepticism about things girls usually find important, like horoscope etc...).
However, I'm willing to share one of the strategies that works very nicely for me. I know a lot of smart and humorous quotes, sayings and proverbs. I know so many of them that I can virtually use them all the time to kill two birds with one stone: Make girls laugh and make myself appear smart in their eyes. A deadly combination. An example from a party previous week, which sealed one of the girls for me. I was in a group of people with a few girls talking about how to stop biting nails. I jumped in and said:"Stop biting nails? That's the easiest thing on the world to do! I've done it at least 50 times up to now!" A killer blow that made them all laugh, made me smart in their eyes and also showed them that I have no problem to make fun out of myself. (Original quote:"It's easy to give up smoking. I've done it thousands of times." ~ Mark Twain)
Yes, outer appearance is important, no doubt about that, but combination of appearing confident, smart and humorous takes the cake any day.
My 2 cents. PUAs, please correct me

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