timorl @timorl@social.cleverlibre.org

One meter is technically defined by the speed of light and a Cs-133 clock at 9.2 GHz, but it's not very practical. For real-world length measurement tasks you use light interferometry. But how do you obtain traceability from a microwave frequency to visible light?

Easy! Here how: Lock a hydrogen clock to the cesium clock first because for better short-term stability, then lock a 100 MHz crystal oscillator to the hydrogen clock to get started. Then, lock a 22.7 GHz Gunn oscillator to the 100 MHz crystal oscillator with a mixer and a PLL. Next, lock a 386.5 GHz Backward Wave Oscillator to the Gunn oscillator. Next, derive a 4251.76 GHz methanol laser from the BWO. Next, derive the 13C 16O2 laser at 29770.665 GHz from that with a mixer, a counter and a 8.99 GHz Gunn oscillator. Next, derive a 29477.165 GHz CO2 from that with a mixer, a PLL, and a 73.35 GHz Klystron oscillator. Next, derive a 28464.674 GHz laser, which derives a 28464.684 GHz then a 29477.165 GHz laser with a mixer, .... #electronics

agda (not to be confused with ada)

In a summary of the paper on Cambridge's security research blog, the researchers explain that even if you start with unbiased - that is, broadly representative - data, the *order* in which you present that data to a machine-learning model can induce bias:

https://www.lightbluetouchpaper.org/2021/04/23/data-ordering-attacks/

That's because ML models are susceptible to "initialization bias" - whatever data they see first has a profound impact on the overall weighting of subsequent data. Here's an example from the researchers' blog:

9/

Pick an encryption method that we know is vulnerable to quantum computers.

Encrypt a drive with it, and fill it up with a bunch of stuff currently important to you.

Conveniently forget the decryption key, put the drive in storage.

Perhaps one day you’ll be able to open this time capsule. ​

Pe Lang has a temporary exhibition in Paris (in https://www.deniserene.fr/) until ~first week of July: https://bibliogram.art/p/Cdf2MDjseRm

Pe Lang makes artifacts that, for me, show some nonobvious or obvious-but-often-overlooked physical property. https://www.pelang.ch/works.html has some examples (but even not the ones I liked most when I saw his exhibition in, sadly defunct, museum of digital art in Zürich).

it's crazy: the first cultural experience of metrics, tracking and the politics of proxies is not in social media. it is being graded at school.

.hg i want a way to put E into tapioca pearls so that we can have

booba tea