Weekend Reads 11/21/15

Beware of ads that use inaudible sound to link your phone, TV, tablet, and PC

The ultrasonic pitches are embedded into TV commercials or are played when a user encounters an ad displayed in a computer browser. While the sound can't be heard by the human ear, nearby tablets and smartphones can detect it. When they do, browser cookies can now pair a single user to multiple devices and keep track of what TV commercials the person sees, how long the person watches the ads, and whether the person acts on the ads by doing a Web search or buying a product.

Science Doesn’t Work the Way You Might Think

But actually, the mystery that convinced Einstein had gone unsolved for over half a century—and no one, not even Einstein himself until the very end, had recognized the phenomenon for what it was: a decisive challenge to Newton’s whole approach.

A classic formula for pi has been discovered hidden in hydrogen atoms

While comparing these values to conventional calculations, he noticed an unusual trend in the ratios. He asked Friedmann to help him work out this trend, and they quickly realised that it was actually a manifestation of the Wallis formula for pi – the first time it had even been derived from physics.

The Economy Is Better — Why Don’t Voters Believe It?

The easiest explanation for this paradox is that it isn’t a paradox at all: Americans are pessimistic about the economy because, for many of them, the economy hasn’t gotten better. Unemployment is down, but incomes are flat. Millions of Americans left the labor force in the recession and haven’t returned. Millions more are stuck in low-wage jobs or are working part time because they can’t find full-time work.