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by pbjtime 971 days ago
>In 2017, such an event occurred

Negative. In 2017, such an event was observed.

4 comments

I’m going to be honest with you. I too used to be pedantic like this until one day I realized it’s really fucking annoying. Now let me tell you why you are wrong. :)

I’m fine with “occurred”. Because of causality the event had absolutely no impact on our local spacetime until those gravitational waves and photons showed up, regardless of how far back in time the event originated.

Another way to think about it: Because the photons and gravitational waves have no mass, no time occurred from their perspective between their origination point and arriving at earth.

I have no qualifications BTW. I just like physics. There’s a decent chance I’m wrong.

I believe that sentence is fine as the event in question is the lagging signals being observed.

> On August 17, 2017, the signal from an event that occurred 130 million light-years away finally arrived here on Earth.

So, it was observed but it did not occur? Could you expand this a little?
Bc of travel distance, meybe they mean that it occured earlier but observed than
It did not occur at the source of event, because at source gravitational waves and light waves were probably pretty close together, so "not simultaneous arriving of light and grav waves" is an event which was observed as happening on Earth in 2017.
Reddit.com is a different website.