5 ms·

I am not sure why but I am really hung up on the quote “Finally, astronomy grew ears. We never had ears before.” They are detecting gravitational waves not so

I am not sure why but I am really hung up on the quote “Finally, astronomy grew ears. We never had ears before.” They are detecting gravitational waves not sound waves.

swamp40 11y ago
The interference pattern is audible - a chirp that "rose to the note of middle C".
- wuliwong 11y ago
  Interference patterns from two lasers do not make any sound. You can take data describing the interference pattern and convert it to a signal that is run through a speaker but that doesn't mean the interference pattern is audible. The amazing thing is they detected gravitational waves, not that they hooked up a speaker to the data. I think a proper analogy would be if back when someone created the first function generator they connected it to a speaker. Then in an interview the main message they delivered was that you could now "hear electricity." It just seems like they are focusing on an afterthought. I also have no idea why I am so fixated on this. :-p
fsloth 11y ago
Any vibration is just a signal. We don't actually have a direct experience with a sound, hearing is our brains interpreting the nerve signals generated by tiny organelles jiggling in our ears. What is concrete then, is only the shape of the signal, but not the medium through which it propagates. This device just acts like a gigantic hearing device. Except it's not pressure waves, but the fabric of the universe which reverbates. Note that the frequency of the signal is indeed in the audible range. Anyway, I was a bit irritated of this same phrase, but because I tought radio astronomers had been listening to skies for quite some time now.
- wuliwong 11y ago
  I think it bothers me because it is focusing on the sound that some small piece of this operation creates when the amazing thing is to be able to measure gravitational waves. Who cares if you hook the output of some piece of LIGO up to a speaker or not and make a noise? Unplug that speaker and these results are just as amazing.
- delecti 11y ago
  > Anyway, I was a bit irritated of this same phrase, but because I tought radio astronomers had been listening to skies for quite some time now. Radio waves are light too though. Or at least they're photons.
noselasd 11y ago
It's perhaps not the perfect metaphor. But up till now all we have really directly observed from outside[1] our solar system are electromagnetic waves(of various wavelengths including visible light), and this is something quite different. http://gmunu.mit.edu/sounds/sounds.html http://gmunu.mit.edu/sounds/sounds.html has a bit more info on why scientists tend to use the sound analogy when talking about gravitational waves. [1] Maybe not entirely true, we have convincing evidence of some extra-solar dust reaching earth too..
ajkjk 11y ago
It is a bit awkward, but, I kinda like it: it's not common in physics for signals to come at frequencies that are actually audible, and these ones definitely are.

I am not sure why but I am really hung up on the quote “Finally, astronomy grew ears. We never had ears before.” They are detecting gravitational waves not sound waves.

swamp40 11y ago

The interference pattern is audible - a chirp that "rose to the note of middle C".

wuliwong 11y ago
Interference patterns from two lasers do not make any sound. You can take data describing the interference pattern and convert it to a signal that is run through a speaker but that doesn't mean the interference pattern is audible. The amazing thing is they detected gravitational waves, not that they hooked up a speaker to the data. I think a proper analogy would be if back when someone created the first function generator they connected it to a speaker. Then in an interview the main message they delivered was that you could now "hear electricity." It just seems like they are focusing on an afterthought. I also have no idea why I am so fixated on this. :-p

fsloth 11y ago

Any vibration is just a signal. We don't actually have a direct experience with a sound, hearing is our brains interpreting the nerve signals generated by tiny organelles jiggling in our ears. What is concrete then, is only the shape of the signal, but not the medium through which it propagates. This device just acts like a gigantic hearing device. Except it's not pressure waves, but the fabric of the universe which reverbates. Note that the frequency of the signal is indeed in the audible range. Anyway, I was a bit irritated of this same phrase, but because I tought radio astronomers had been listening to skies for quite some time now.

wuliwong 11y ago
I think it bothers me because it is focusing on the sound that some small piece of this operation creates when the amazing thing is to be able to measure gravitational waves. Who cares if you hook the output of some piece of LIGO up to a speaker or not and make a noise? Unplug that speaker and these results are just as amazing.
delecti 11y ago
> Anyway, I was a bit irritated of this same phrase, but because I tought radio astronomers had been listening to skies for quite some time now. Radio waves are light too though. Or at least they're photons.

noselasd 11y ago

It's perhaps not the perfect metaphor. But up till now all we have really directly observed from outside[1] our solar system are electromagnetic waves(of various wavelengths including visible light), and this is something quite different. http://gmunu.mit.edu/sounds/sounds.html http://gmunu.mit.edu/sounds/sounds.html has a bit more info on why scientists tend to use the sound analogy when talking about gravitational waves. [1] Maybe not entirely true, we have convincing evidence of some extra-solar dust reaching earth too..

ajkjk 11y ago

It is a bit awkward, but, I kinda like it: it's not common in physics for signals to come at frequencies that are actually audible, and these ones definitely are.