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Timeline of the far future

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Re: Timeline of the far future

#141

Post by garmaine »

marviel wrote: post #109
improv32 wrote: post #76

Earlier quoted context omitted.

It's been suggested that perhaps one way to find evidence of extrasolar life, would be to find exoplanets whose years are integer multiples of their rotational periods, i.e. they've done what you describe just to eliminate leap years and make their calendars easier.

That is fascinating! Do you have a reference?

I think he might be sarcastic. There is no known method I know for measuring the rotational period of extrasolar planets, without having enough observational power to defiantly notice the astronomical engineering required to alter an inhabited planet’s rotation rate.

Re: Timeline of the far future

#143

Post by vinceguidry »

baddox wrote: post #59
AgentME wrote: post #44

Earlier quoted context omitted.

Maybe some Boltzmann brains start out with rich fulfilling memories. And then a later (or earlier) Boltzmann brain happens to exist with a continuation of those memories. (Now I realize I'm just reciting a plot point from the excellent book Permutation City ...)

And likewise, maybe others start out in a state of unimaginable agony with a long memory of the same.

Does self-awareness presume the existence of emotion? I feel like Boltzman wouldn't have bothered to assert self-awareness if he'd had a real knowledge of the various gradations of consciousness and just how rare they are, even on Earth.

Re: Timeline of the far future

#144

Post by walrus01 »

cpeterso wrote: post #130
21 wrote: post #8

> The length of the day used for astronomical timekeeping reaches about 86,401 SI seconds. Under the present-day timekeeping system, either a leap second would need to be added to the clock every single day, or else by then, in order to compensate, the length of the day would have had to have been officially lengthened by one SI second. Can you just imagine the amount of legacy code with DAY_SECONDS=86400 out there 5…

In Vernor Vinge's A Fire Upon the Deep and A Deepness in the Sky novels, the characters in the far future track time using megaseconds (~11.6 Earth days) to sidestep the problem of days with different lengths. They still count from the 1970-01-01 Unix epoch, but the characters mistakenly think that date is when humans landed on the moon.

There's also such a thing as a Programmer-Archeologist, can you imagine dealing with 14,000 years of nested dependencies? One key plot point in one of the novels, a totalitarian group is running a omnipresent surveillance network but has no idea about the software running underneath it. They set it up using the GUI and are using it but never looked under the hood. The group attempting to get out from under the grasps of the totalitarians has a programmar-archaeologist who digs into the underpinnings of the software and hijacks it from a lower level of its operating system.

Re: Timeline of the far future

#145

Post by taneq »

andbberger wrote: post #63
netgusto wrote: post #2

Fascinating: "10^(10^50) years: Estimated time for a Boltzmann brain to appear in the vacuum via a spontaneous entropy decrease." [1] [1] https://en.wikipedia.org/wiki/Boltzmann_brain > [...] a Boltzmann brain is a self-aware entity that arises due to extremely rare random fluctuations out of a state of thermodynamic equilibrium. [...]

That is __severely__ underestimating the true probability - it considers only random thermal fluctuations. But the universe is really powered by processes that dissipate energy across a gradient to fuel a structured, very low entropy state. The math is the same as calculating the probability that the glass you just broke will spontaneously jump back onto the table and reassemble itself. Which is a standard introducto…

> processes that dissipate energy across a gradient to fuel a structured, very low entropy state

You mean like... life?

Re: Timeline of the far future

#146

Post by mkempe »

24gttghh wrote: post #102

>Goldstein, Natalie (2009). Global Warming. Infobase Publishing. p. 53. "The last time acidification on this scale occurred (about 65 mya) it took more than 2 million years for corals and other marine organisms to recover; some scientists today believe, optimistically, that it could take tens of thousands of years for the ocean to regain the chemistry it had in preindustrial times." In my opinion, this is the greates…

One should maintain some perspective: Coral reefs have gone through enormous variations in extent and location, and near extinction, many times since 500 million years ago. Not even the last Ice Age or CO2 levels 10x higher than what we have today managed to cause the extinction of coral.

Re: Timeline of the far future

#147

Post by taneq »

Florin_Andrei wrote: post #18
netgusto wrote: post #2

Fascinating: "10^(10^50) years: Estimated time for a Boltzmann brain to appear in the vacuum via a spontaneous entropy decrease." [1] [1] https://en.wikipedia.org/wiki/Boltzmann_brain > [...] a Boltzmann brain is a self-aware entity that arises due to extremely rare random fluctuations out of a state of thermodynamic equilibrium. [...]

Fun fact: most Boltzmann brains pass out in a matter of seconds, then die, and there's nothing they can do about that.

This fact is not fun.

Re: Timeline of the far future

#148

Post by techdragon »

garmaine wrote: post #141
marviel wrote: post #109

Earlier quoted context omitted.

That is fascinating! Do you have a reference?

I think he might be sarcastic. There is no known method I know for measuring the rotational period of extrasolar planets, without having enough observational power to defiantly notice the astronomical engineering required to alter an inhabited planet’s rotation rate.

Actually I think if we follow the current trend in technology advances in astronomy, we will definitely be able to measure planetary rotation well before we have the angular resolution to spot anything of consequence on an exoplanet. We currently have the technology to measure stellar rotation bia Doppler shift. https://en.m.wikipedia.org/wiki/Stellar_rotation

This technique will definitely be applied to exoplanets as the angular resolution and spectroscopic sensitivity are improved. In fact, improvements to both if these numbers are being relentlessly pursued by a veritable army of scientists around the world.

Spectral broadening only needs one pixel, and enough spectral sensitivity that the broadening isn’t entirely in the margin of error. We are pushing For ever more accurate spectral sensitivity as we try to use Doppler measurement to hunt for exoplanets.

Meanwhile the ongoing efforts to obtain greater angular resolution, has basically been one of the core pursuits of the astronomical community for centuries. We are building massive telescopes and advanced compensation systems in the form of adaptive optics to get the very best out of these telescopes.

So yeah I think we’re going to have rotation rate measures before we see much more than a pale blue dot.

Re: Timeline of the far future

#149

Post by taneq »

TrainedMonkey wrote: post #49
cpburns2009 wrote: post #34

Earlier quoted context omitted.

This feels anecdotal rather than an actual calculation.

Assuming that time moves forward, probability of all events that have already happened is 1. Probability of all events that could have happened, but did not 0. There is an interesting parallel that could be made to quantum states collapsing. Given that the question asks about 'current' universe arising spontaneously from vacuum the probability is 1 because that has already happened. The more interesting question, wha…

> Given that the question asks about 'current' universe arising spontaneously from vacuum the probability is 1 because that has already happened.

Well, we don't know that. Whatever 'came before' (if that even makes sense) probably wasn't a vacuum with the same rules as we see now.

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