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Not long ago, the center of the Milky Way exploded

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Re: Not long ago, the center of the Milky Way exploded

#91
post #41

Given that we're able to aim telescopes at things that are billions of light years away, I wonder how close we are to being able to see the reflection of such a thing when it actually happens on some celestial body 3.5 million light years away.

I remember as a child thinking I had fixed time travel (in a very limited sense) when I wondered why we didn't just stick a bunch of mirrors far far away, and then aim them back at the earth and use telescopes to look back at the dinosaurs etc. While that wouldn't work for heaps of reasons, I like your idea. I guess the issue would be discerning 'when' such a thing happened, and finding the right item to look back at…

:) https://news.ycombinator.com/item?id=9161967

Re: Not long ago, the center of the Milky Way exploded

#92

Earlier quoted context omitted.

And yet few have ever heard this Larry while Millard Fillmore maintains the distinction of being the president with the coolest name. If only Spiro T. Agnew would have made it.

I have heard of Larry Niven and never heard of Millard Fillmore. Being outside the US I never covered past US presidents in school.

Even if the US, he isn't someone who would be covered.

Re: Not long ago, the center of the Milky Way exploded

#93

Earlier quoted context omitted.

Is there a name for some kind of inverted Kardashev scale, where higher civilizations decide to slow down and go miniature, conserving as much energy and information as possible? Possibly as a) some kind of bet to hide from other civilizations and b) to delay the heat death as long as possible.

My go-to entry point for exploring those kinds of questions was Isaac Arthur. He goes into the Kardashev scale [1], dying Earth [2], dying stars [3], farming black holes [4], and going past iron stars [5]. A Boltzmann Brain's description bears remarkable similarity to the Judeo-Christian concept of God before time begins, and has been fertile ground for ruminations [6], though none with any verifiable claims backing…

Great list! I'm bookmarking this.

Re: Not long ago, the center of the Milky Way exploded

#94

Earlier quoted context omitted.

Why, though? It seems to me that the long term payoff of colonizing Mars is huge. The long term payoff of colonizing remote and inhospitable areas on earth is many, many orders of magnitude lower. I can maybe rationalize that effort if we simply assume that those areas are similar enough to Mars that the experience and technology developed while doing it could be applied effectively. But I'm not really convinced that…

Experiments on Mars cost way more, and small mistakes are likely to destroy the whole colony. Anything we can learn on Earth is much easier to learn here.

> Anything we can learn on Earth is much easier to learn here.

Not true for "is/was there life on other planets in the solar system".

Re: Not long ago, the center of the Milky Way exploded

#95
post #62

They probably would've mentioned this in the article were it the case, but I wonder if it was visible at all in the night sky? We can see part of the Milky Way, after all. I guess there wouldn't have been writing yet but could such a thing have made it into oral history? Was there even oral history yet?

No oral history, sorry. 3.5MYA, we were still Austropithecenes, basically as smart as a modern day chimp or gorilla, but bipedal. The little numbers in the tree here show divergence time:

https://en.wikipedia.org/wiki/Australopithecus#Phylogeny

Re: Not long ago, the center of the Milky Way exploded

#97
post #9

Earlier quoted context omitted.

In cosmological terms, it's more like "earlier today". Our ancestors were already walking around, talking to black monoliths and crushing skulls by then.

I hate that movie.

Oof. Harsh, HN, harsh, downvoted for disliking a (albeit very loved) movie.

Re: Not long ago, the center of the Milky Way exploded

#98
post #87
post #41

Earlier quoted context omitted.

I remember as a child thinking I had fixed time travel (in a very limited sense) when I wondered why we didn't just stick a bunch of mirrors far far away, and then aim them back at the earth and use telescopes to look back at the dinosaurs etc. While that wouldn't work for heaps of reasons, I like your idea. I guess the issue would be discerning 'when' such a thing happened, and finding the right item to look back at…

You need natural mirrors, because as others have pointed out, they have to already be there, you can't get ahead of the light to put them there. It has been suggested that black holes could provide this mirror, but it requires resolving not just something the size of Earth, but something much smaller , at a distance of 30 million light years +. Unfortunately you actually start hitting up against the limits of spaceti…

What are these "limits of spacetime's resolution" you speak of?

Beyond speculation, I'm not aware of anything showing spacetime to be discrete.

Re: Not long ago, the center of the Milky Way exploded

#99
post #59

Earlier quoted context omitted.

Larry Niven is still relevant while Millard Fillmore is not.

And yet few have ever heard this Larry while Millard Fillmore maintains the distinction of being the president with the coolest name. If only Spiro T. Agnew would have made it.

I've never heard of Millard Fillmore before.

Re: Not long ago, the center of the Milky Way exploded

#100
post #9

Earlier quoted context omitted.

In cosmological terms, it's more like "earlier today". Our ancestors were already walking around, talking to black monoliths and crushing skulls by then.

The Krell, on the other hand, were near the peak of their development.

Their Great Machine is a metaphor for social networking. I'm quite sure it'll kill us all.
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