It was cloudy, so we didn't need much sunscreen. We swam in the sea, played volleyball and frisbee, and ate the birthday cake. It was a great beach party.

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Maybe one day I will get a plasma ball in my office, to show that it's a plasma research office.

Maybe one day there will be bluetooth version of those stuff, although it's hard for the bluetooth power to drive the plasma ball. However, maybe one day such a plasma ball or torus can generate fusion energy, and then you can plug your computer, lamp, speakers, microwave, fridge and other stuff in the plasma ball/torus to get them powered up.

Yesterday at Albertsons, I saw a small fruit pack sold for about $10. I thought, "Wow, this is crazy." And then I realized, "Oh, yeah. That's what they say about themselves: Albertsons, crazy about food."

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Had a nice barbecue. Played some softball. Unfortunately didn't have a chance to watch the fireworks.

Some web pages[1-4] are describing a method to measure speed of light using a microwave oven. They claim that by removing the turntable, hot spots can be found in the microwaved material (food). And the distance between two neighboring spots corresponds to the half wavelength of the microwave, which can be measured to be around 6cm. Then they can calculate the speed of light by using a wave formula,
,            (1)
where c is the speed of light, λ is the wavelength, and f is the frequency of the microwave which can be obtained in the sticker on the back of the oven and which is usually 2.45GHz.

Eq. (1) is valid for a monochromatic plain wave. For other forms of electromagnetic field (E&M field), we have to be careful. Apparently, the size of the oven is at the same order (~10cm) of the "wavelength" of the microwave, so the oven cannot be approximated to be infinitely large and, hence, the E&M field cannot be simply approximated to be a monochromatic plain wave. Also obviously, the oven cannot be approximated to be a pair of infinitely large walls, so the E&M field cannot be approximated to be a 1D standing wave. Therefore, we have to solve the Maxwell equations to see what is actually going on in the oven. And then we can see the physical validity of this method.

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