The Big Think

September 12, 2013


Filed under: Science — jasony @ 3:07 pm

New measure of gravitational constant higher than expected:

“A trio of researchers working in France, along with a colleague from the U.K. has re-measured the gravitational constant using the same apparatus they built 12 years ago and have found a small change. In their paper published in Physical Review Letters, the team describes how they reconfigured their original equipment to re-measure the gravitational constant and this time came up with a slightly higher number than before.

The gravitational constant, denoted by G in math equations, has proven to be far more elusive than scientists imagined after it was first measured by Henry Cavendish approximately 200 years ago. The problem is that it’s far weaker than other forces such as electromagnetism. Fluctuating stronger forces acting on measurement equipment can cause changes to readings, leading to an inaccurate result. For that reason, scientists have been striving to come up with a way to definitively measure exactly how much force G exerts. In this new effort, the research team went back to the same apparatus they constructed 12 years ago—one that simultaneously measures G in two different ways. This time around, however, they reconfigured their device in ways they believed would make it more accurate—and in so doing found a slightly different result, but now, aren’t sure which of their measurements is actually more accurate.

Modern researchers use two main types of methods to try to measure G, the first is a more advanced way to do the same thing Cavendish did two centuries ago, using lasers instead of candle light—it’s based on measuring the amount of torque applied to a thin ribbon set between heavy balls. The other involves applying voltage to a wire using a servo to counteract twisting due to G. In this renewed effort, the researchers ran both types of measurements in their device and averaged the results. In so doing, they discovered measurements revealed a value of 6.67545(18)x10-11 m3 kg-1 s-2, with 27PPM standard uncertainty. This value is 21PPM lower than the last time they ran the experiment (measurements by others have ranged as far as 241 ppm lower). The team is unable to explain why they found a difference, and cannot say with confidence which of their measurements is likely closer to G’s actual value.”

Pump Up the Volume

Filed under: Audio — jasony @ 1:24 pm

The Web Is Too Quiet. It’s Time to Pump Up the Volume | Wired Opinion |

“‘The web,’ as venture capitalist Fred Wilson has said, ‘is still too quiet.’

But a few of the noisier places on the net are getting louder. The audio-sharing site SoundCloud (in which Wilson is an investor) has been online since 2008, but it’s now inching toward YouTube-like status.

Users upload 12 hours of audio every minute. The lion’s share is music, but you can find weirder stuff: activists capturing the sound of protests (for the political record) or an audiophile recording the strangely gorgeous sound of ice melting (for… the heck of it). This spring, astronaut Chris Hadfield posted a series of ambient sounds recorded on the International Space Station, and listeners found them mesmerizing. A picture of the Soyuz module may convey 1,000 words, but hearing its eerie hum? That transports you there.

‘When you hear sound, there’s a lot of implicit knowledge in it,’ says SoundCloud CEO Alexander Ljung. Sound is also emotionally loaded, he points out. Watch a scary movie with the volume off and it’s no longer so creepy.”

I agree with the author’s point that there have been many new tools developed in recent years for video and the written word (editing suites, graphical programs, web standards) but comparatively few for the audio world. This tends to reinforce my thinking that audio and sound are easily overlooked (both in daily life and in things like movies and commercials). We all experience audio every waking second but don’t often think about it unless there’s something wrong- a ringing in your ears, badly mixed or edited movie audio, an annoying barking dog.

As for myself, I’m notoriously aware of my sonic surroundings and it drives me nuts. I need to sleep with earplugs in just so I can sleep. A year or so ago we had a washing machine overflow and leave a thin film of creeping water on the linoleum floor downstairs. I could tell this was happening from my studio upstairs just by the fact that the high frequencies were reflecting around in an unusual way. I went down to investigate and fixed the leak before it got out of control. But this is doubtless tied to the fact that I spend much of my working day with my eyes closed just listening to sounds, picking orchestras apart, hearing mixes, etc.

In my experience, though, most people just aren’t that aware of what goes on around them sonically, and it’s a real loss for them. It’s also one of the reasons that I recently got out of the production mixing/recording side of the audio world. Far too many directors give lip service to sound but don’t know the first thing about what’s required to get a good mix, nor are they willing to give time to doing it right.

Anyway, blah blah blah sound. It’s good stuff. Listen to it sometime.

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