The Nice People Thread, No.16: A Universe of Niceness.

Pyxis

This is a recording of the sound.


NB, the collision in question is the bottom yellow line.

There is a tiny click right at the beginning, but you need to wait until the very end, 55 seconds in, to hear the whirrr...pop.

As a sound, , it's underwhelming, until you realise that it occurred billions of miles away, 130 million years ago, and that it is thought that the collision of neutron stars is where some of the heavy elements, like gold, came into existence.
This event may even lead to some of the gaps in the periodic table being filled in...... new elements!

GDB2222

If it occurred 130 million years ago, and the gravitational waves travelled at the speed of light, then the distance was 130 million light years. Light travels 300000 km per second in vacuum, so that’s a distance that’s beyond my ability to imagine.

Pyxis

GDB2222 wrote: »

If it occurred 130 million years ago, and the gravitational waves travelled at the speed of light, then the distance was 130 million light years. Light travels 300000 km per second in vacuum, so that’s a distance that’s beyond my ability to imagine.

I know!
(Is there a boggle boggle emoticon?)

It was a thousand billion, billion km away in the Constellation Hydra.
(I meant to say billions of miles in my previous post! )




And when it happened, there were dinosaurs on earth.

This is one of the two LIGO observatories in the
States. The long pipe thing is the detector.......



It was only because a new similar one in Europe.... VIRGO....was working with the two LIGO ones that the signals were picked, up, that and some other strokes of good luck.

It will apparently have far-reaching scientific consequences.

This is another very informative article which explains how the strokes of good luck all came together to result in this find.....

https://www.quantamagazine.org/neutron-star-collision-shakes-space-time-and-lights-up-the-sky-20171016/

Pyxis

I was trying to convert that distance to miles, but started drowning in noughts, so gave up.

Probably wouldn't be any easier to envisage anyway! :rotfl:

chris_m

Two pertinent quotes from The Hitchhiker's Guide to the Galaxy;

"Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space."

"Nothing travels faster than the speed of light with the possible exception of bad news, which obeys its own special laws."

Pyxis

Pyxis wrote: »

I was trying to convert that distance to miles, but started drowning in noughts, so gave up.

Probably wouldn't be any easier to envisage anyway! :rotfl:

chris_m wrote: »

Two pertinent quotes from The Hitchhiker's Guide to the Galaxy;

"Space is big. You just won't believe how vastly, hugely, mind- bogglingly big it is. I mean, you may think it's a long way down the road to the chemist's, but that's just peanuts to space."

"Nothing travels faster than the speed of light with the possible exception of bad news, which obeys its own special laws."

Exactly! :rotfl:

It be ooge!

No point in trying to be too exact about the distance! :rotfl:
(I shall switch off my nit-picking mode! )

GDB2222

Now here's a question for the clever people here.

In space there's hypothesised to be a very small amount of ordinary matter, and rather more (roughly ten times as much) dark matter. Light waves interact with the ordinary matter, but not the dark matter. Gravitational waves interact with both. So, does this interaction slow down the gravitational waves, and if so is there a measurable time difference between the arrival of the visible light and the gravitational waves after 130 million years?

Pyxis

GDB2222 wrote: »

Now here's a question for the clever people here.

In space there's hypothesised to be a very small amount of ordinary matter, and rather more (roughly ten times as much) dark matter. Light waves interact with the ordinary matter, but not the dark matter. Gravitational waves interact with both. So, does this interaction slow down the gravitational waves, and if so is there a measurable time difference between the arrival of the visible light and the gravitational waves after 130 million years?

michaels

I like the rubber sheet analogy for how the detectors work. Gravity waves are ripples in the sheet, they can not be detected directly as everything on the sheet is being streched and compressed in the same way so to the observer on the sheet nothing is happening; but if you send out light in two directions at right angles and wait for it to be bounced back off two mirrors equidistant away, if space time is being compressed and stretched in one direction and not the other (as will happen with gravity waves originating form a single point) then actually the light will not take the same length of time to make the two 'identical' length journeys.

Of course in reality your rubber sheet has 3 spacial dimensions and a temporal one but the analogy becomes harder to get your head round if you try to think in 4 dimensional space time....

Pyxis

On a graph of subjects that I'm good at, physics drops off the bottom of the y axis.

I don't think I've evolved enough to understand it.
The physics part of my brain-power is on a level with an amoeba.

It's very annoying.

I understood stuff up to the lesson on rolling a boulder up an incline, but then my brain shut and the boulder squashed me.
Never been the same since.



I think I'll have to steal some genes from Quasar.