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Possible false signals in LIGO via the detection of radio-waves. See: Ultra sensitive detection of radio waves with lasers https://www.nbi.ku.dk/english/new

Possible false signals in LIGO via the detection of radio-waves. See: Ultra sensitive detection of radio waves with lasers https://www.nbi.ku.dk/english/news/news14/ultra-sensitive-detection-of-radio-waves-with-lasers/ https://www.nbi.ku.dk/english/news/news14/ultra-sensitive-de... It would be interesting to see how this method of EM-wave detection interferes with the GW-detection.

tobinfricke 7y ago
Radio signals could definitely interfere with LIGO, and show up with consistent time delays corresponding to some sky position. There are two defenses against this: 1. At the LIGO observatories there are numerous auxiliary sensors, including radio receivers, that are used as "vetoes" for candidate gravitational wave events. 2. For binary black hole or neutron star inspirals, the gravitational wave waveforms are well-modeled using numerical general relativity. The fact that the observed detection matches the prediction so well lends additional credibility to the detection. Regarding #2, we are of course hoping to detect something unexpected, with an unknown waveform. In those cases we'll rely on the veto channels to ensure that we have not detected contamination from a radio event.
- zyxzevn 7y ago
  Good reply, but.. Regarding 1: In the article, they describe an antenna that is MORE sensitive than the normal antennas. So you may not be able to detect the low frequency radio-waves without a similar sensitive apparatus. Regarding 2: There is the problem that Electric signals can have high similarities with the "Chirps" that LIGO is looking for. For example: even in space, you can find all kinds of "chirps" caused by solar plasma. google "noises from space".
  - tobinfricke 7y ago
    1. I took a look at the attached article. The device they describe is an optomechanical setup specifically engineered to be very sensitive to radio waves. LIGO, by contrast, is engineered to be sensitive to gravitational waves and not radio waves. 2. This point is valid.
therein 7y ago
Wouldn't the detector be placed inside a Faraday cage to keep away any and all EM emissions?

tobinfricke 7y ago

Radio signals could definitely interfere with LIGO, and show up with consistent time delays corresponding to some sky position. There are two defenses against this: 1. At the LIGO observatories there are numerous auxiliary sensors, including radio receivers, that are used as "vetoes" for candidate gravitational wave events. 2. For binary black hole or neutron star inspirals, the gravitational wave waveforms are well-modeled using numerical general relativity. The fact that the observed detection matches the prediction so well lends additional credibility to the detection. Regarding #2, we are of course hoping to detect something unexpected, with an unknown waveform. In those cases we'll rely on the veto channels to ensure that we have not detected contamination from a radio event.

zyxzevn 7y ago
Good reply, but.. Regarding 1: In the article, they describe an antenna that is MORE sensitive than the normal antennas. So you may not be able to detect the low frequency radio-waves without a similar sensitive apparatus. Regarding 2: There is the problem that Electric signals can have high similarities with the "Chirps" that LIGO is looking for. For example: even in space, you can find all kinds of "chirps" caused by solar plasma. google "noises from space".
- tobinfricke 7y ago
  1. I took a look at the attached article. The device they describe is an optomechanical setup specifically engineered to be very sensitive to radio waves. LIGO, by contrast, is engineered to be sensitive to gravitational waves and not radio waves. 2. This point is valid.

therein 7y ago

Wouldn't the detector be placed inside a Faraday cage to keep away any and all EM emissions?