5 ms·
From the abstract of the paper, energy equivalent to three solar masses were radiated away in gravitational waves. That's a simply incredible amount! Possibly
by scrumper 11y ago
From the abstract of the paper, energy equivalent to three solar masses were radiated away in gravitational waves. That's a simply incredible amount!
Possibly stupid question: Given how far away it was, and that the inverse square law applies, would the effect of these waves be visible on the human scale if we were closer? We can see the effects of the compression of spacetime with LIGO after all, so presumably we could?
- Semiapies 11y agoYeah,I got to the point mentioning the masses of the black holes before and after collision and said, "What, they didn't just lose three solar masses..." But, they did. Which was the order of predictions I'd read, years back, but egads. Considering how much larger that is than a supernova, I'd be concerned to have such an event happen in this galaxy...
- mturmon 11y agoYes, mind-boggling. 3 solar masses converted to energy in just a few seconds.
- adrianN 11y ago0.5 seconds actually.
- pja 11y agoThe energy is dumped into gravitational waves rather than electromagnetic radiation & they don’t interact with matter much. I’m not sure you’d notice it happening in the same galaxy unless you were looking for it.
- deleted 11y ago[deleted]
- bzbarsky 11y agoThis thing was a billion light years away. Say it were closer; let's put it at a single light year away. LIGO measures wave amplitude, as far as I can tell, which goes down linearly with distance (unlike wave energy, which goes down quadratically, since it's proportional to square of the amplitude). So we could expect to see an effect about a billion times bigger. The detected effect was a change in metric of one part in 6e20 if I'm not mistaken: (4e-3 * (diameter of proton))/4km based on the article's claim of "four one-thousandths of the diameter of a proton". So at one light year distance we could expect an effect of one part in 6e11. Not really visible on the human scale, seems to me. You could detect it easily with something like the Mössbauer effect, I expect. Your typical lab bench laser interferometer has errors on the order of 1 in 1e6 as far as I can tell, so probably wouldn't be able to pick this up. Disclaimer: I could be totally off on what a lab bench laser interferometer can do. I'm pretty confident in the rest of the numbers above.
- yellow_postit 11y agoWhat I didn't understand after reading the article is how do they separate out a set of waves for one specific thing vs. the many other objects sending out waves. Is it just that the set of blackholes are the strongest set of waves and thus the ones we can detect?
- bzbarsky 11y agoThat, and the high frequency. For example, the Earth orbiting the Sun produces gravitational waves at a frequency that's about (factors of 2 and pi here and there) the orbital frequency; order of 1e-8 Hz. The black holes were producing 250Hz waves if I read the article right.
- scrumper 11y agoI see, thanks.
- ISL 11y agoThe longer the interferometer arms, the better you can do in sensitivity. The reason LIGO has 4000 m long arms is that it makes the experiment 4000x more sensitive than something you can do on a bench. (and their laser stabilization is excellent, improving things further)
- contravariant 11y agoIn this case it's not an inverse square law, the amplitude is simply inversely proportional to the distance.
- InclinedPlane 11y agoYup. Possibly one of the most energetic events in the Universe. Fascinating in many ways when you think about it. That mass was once matter, and somehow it got converted into gravitons.