<p>Gravitational waves from the big bang may be "heard" but not by LIGO. The waves emitted at or around the inflationary epoch of the big bang are expected to be at much lower frequencies (milli-Hz or lower) than those announced today by LIGO. There are various sources of noise that make LIGO insensitive to GWs at frequencies below about 10 Hz.</p>

<p>It will take space-based interferometers like the proposed LISA, with longer interferometer arms and well away from terrestrial sources of noise to stand <em>a chance</em> of detecting such GWs.</p>

<p>If they are detected - they might "sound" something like this (if upshifted into the audible range) - <a href="http://www.ligo.org/science/GW-Overview/sounds/stochastic.wav" rel="noreferrer">from the LIGO website</a>. It sounds like white(ish) noise because of the broad continuum of frequencies expected.</p>

CC BY-SA 3.0
2016-02-13T02:07:42.720Z
By mHz, you mean milli-Herz?
Wayfaring Stranger
CC BY-SA 3.0
2016-02-13T09:25:25.997Z
Yes he means mili-Herz
Vojta Klimes
CC BY-SA 3.0
2016-02-13T09:25:56.907Z
@wayfaringstranger Yes. $p$ pico, $n$ nano, $\mu$ micro, $m$ milli, $k$ kilo $M$ mega, $G$ giga, $T$ tera.
ProfRob
CC BY-SA 3.0
2016-02-13T09:28:21.267Z
Actually I mean milli-hertz. !
ProfRob
CC BY-SA 3.0
2016-02-13T15:59:35.273Z
@RobJeffries I added a "duplicate" question that I probably should have just added here, but it is a little different. It was about the locality of the signal. LIGO detected gravitational waves from a localized source. Wouldn't Big Bang GW come from "everywhere"? How would this effect detection?
Jack R. Woods
CC BY-SA 3.0
2016-02-13T16:03:31.050Z
Also, I wanted to know if anybody knows if LIGO has detected any other signals over the last five months. I live in Washington state; will have to go on a "pilgrimage" to Hanford.
Jack R. Woods
CC BY-SA 3.0
2016-02-15T22:35:45.340Z
@RobJeffries Thank you for answering. That's exciting. If the gw can be converted to sound similar to the LIGO discovery that will be even better. Here's link where you can hear it though it sounds rather tame for a collision: http://podcasts.nytimes.com/podcasts/2016/02/11/science/space/ligo-chirp/LIGOChirp.mp3
signsgeek
CC BY-SA 3.0
2016-02-15T23:37:08.027Z
@signsgeek Here it is - just sunds like white(ish) noise, because it is a broad continuum of frequencies. http://www.ligo.org/science/GW-Overview/sounds/stochastic.wav
ProfRob
CC BY-SA 4.0
2021-04-29T17:24:19.730Z
Aren't third-generation detectors also expected to be able to detect early-universe g-waves? For example Big Bang Observer, DECIGO, Cosmic Explorer, etc... https://www.annualreviews.org/doi/full/10.1146/annurev-astro-081915-023433
Daddy Kropotkin
CC BY-SA 4.0
2021-04-29T19:00:15.213Z
Your reference appears to only mention Big Bang Observer and DECIGO, both of which are space-based @DaddyKropotkin These are mooted *successors* to LISA aren't they?
ProfRob
CC BY-SA 4.0
2021-04-29T22:07:19.187Z
Oh I see, yes you're correct about these detectors. I was mistaken. I was thinking about the Einstein telescope: https://arxiv.org/abs/2003.04783 and see section 3.4.1 of https://arxiv.org/abs/1912.02622 where it might be able to probe certain scalar fields of inflationary models (e.g., axions)
Daddy Kropotkin
CC BY-SA 3.0
2016-02-11T23:21:44.633Z
2016-02-15T23:39:27.910Z
2016-02-15T23:39:27.910Z
ProfRob
<ol>
<li>I read in an article announcing the detection of gravitational waves by LIGO that it will be possible to detect them from the Big Bang. Is this true?</li>
</ol>

CC BY-SA 3.0
2016-02-11T21:45:48.980Z
What article is this? Please put a link.
Sir Cumference
CC BY-SA 3.0
2016-02-15T23:08:02.493Z
@SirCumference There's a reference to the beginning of the Universe in this article though it seems like a science writer than an actual physicist answered it msn.com/en-in/news/techandscience/… . There's another one about an earlier claim about gw from the Beginning that was proved false: washingtonpost.com/news/achenblog/wp/2014/09/22/…
signsgeek
<big-bang-theory><early-universe><gravitational-waves>
Is it possible to get a glimpse of the Big Bang through gravitation waves?
signsgeek
# Is it possible to get a glimpse of the Big Bang through gravitation waves?

(Asked by: username_0 on 2016-02-11)

1. I read in an article announcing the detection of gravitational waves by LIGO that it will be possible to detect them from the Big Bang. Is this true?

**Tags:** big-bang-theory, early-universe, gravitational-waves

> **Comments:**
> **username_1**: What article is this? Please put a link.  
> **username_0**: @username_1 There's a reference to the beginning of the Universe in this article though it seems like a science writer than an actual physicist answered it msn.com/en-in/news/techandscience/… . There's another one about an earlier claim about gw from the Beginning that was proved false: washingtonpost.com/news/achenblog/wp/2014/09/22/…  

---

## 1 answers

### Answer by username_2 on 2016-02-11. Score: 7 | Accepted answer

Gravitational waves from the big bang may be "heard" but not by LIGO. The waves emitted at or around the inflationary epoch of the big bang are expected to be at much lower frequencies (milli-Hz or lower) than those announced today by LIGO. There are various sources of noise that make LIGO insensitive to GWs at frequencies below about 10 Hz.

It will take space-based interferometers like the proposed LISA, with longer interferometer arms and well away from terrestrial sources of noise to stand *a chance* of detecting such GWs.

If they are detected - they might "sound" something like this (if upshifted into the audible range) - [from the LIGO website](http://www.ligo.org/science/GW-Overview/sounds/stochastic.wav). It sounds like white(ish) noise because of the broad continuum of frequencies expected.

> **Comments:**
> **username_3**: By mHz, you mean milli-Herz?  
> **username_4**: Yes he means mili-Herz  
> **username_2**: @username_3 Yes. $p$ pico, $n$ nano, $\mu$ micro, $m$ milli, $k$ kilo $M$ mega, $G$ giga, $T$ tera.  
> **username_2**: Actually I mean milli-hertz. !  
> **username_5**: @RobJeffries I added a "duplicate" question that I probably should have just added here, but it is a little different. It was about the locality of the signal. LIGO detected gravitational waves from a localized source. Wouldn't Big Bang GW come from "everywhere"? How would this effect detection?  
> **username_5**: Also, I wanted to know if anybody knows if LIGO has detected any other signals over the last five months. I live in Washington state; will have to go on a "pilgrimage" to Hanford.  
> **username_0**: @RobJeffries Thank you for answering. That's exciting. If the gw can be converted to sound similar to the LIGO discovery that will be even better. Here's link where you can hear it though it sounds rather tame for a collision: http://podcasts.nytimes.com/podcasts/2016/02/11/science/space/ligo-chirp/LIGOChirp.mp3  
> **username_2**: @username_0 Here it is - just sunds like white(ish) noise, because it is a broad continuum of frequencies. http://www.ligo.org/science/GW-Overview/sounds/stochastic.wav  
> **username_6**: Aren't third-generation detectors also expected to be able to detect early-universe g-waves? For example Big Bang Observer, DECIGO, Cosmic Explorer, etc... https://www.annualreviews.org/doi/full/10.1146/annurev-astro-081915-023433  
> **username_2**: Your reference appears to only mention Big Bang Observer and DECIGO, both of which are space-based @username_6 These are mooted *successors* to LISA aren't they?  
> **username_6**: Oh I see, yes you're correct about these detectors. I was mistaken. I was thinking about the Einstein telescope: https://arxiv.org/abs/2003.04783 and see section 3.4.1 of https://arxiv.org/abs/1912.02622 where it might be able to probe certain scalar fields of inflationary models (e.g., axions)  

---

