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The universe is expanding faster than expected

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Re: The universe is expanding faster than expected

#71

Post by [deleted] »

cygx wrote: post #67
User23 wrote: post #63

Earlier quoted context omitted.

Thank you for helping clarify what I'm saying. You've definitely got it right. To elaborate, consider the difference between calculating the distance to a star in the Milky Way using parallax where the model is basically just assume your eyes work plus trigonometry and calculating the distance to other galaxies where far more assumptions are required. Edit: response from cygx is completely missing the point about con…

Which is no different in other branches of physics: Have you ever seen a quark? If you have a model that makes testable predictions, it's science. Cosmology is not only science, but physics, making your original comment contrasting the two kind of nonsensical...

[deleted]

Re: The universe is expanding faster than expected

#72

Post by lisper »

User23 wrote: post #31
lisper wrote: post #24

Earlier quoted context omitted.

No, you are absolutely wrong here. But before I explain why I need to ask a question: are you by chance a young-earth creationist? Because your rhetoric here is very similar to that employed by YECs. (The reason I ask is that my explanation is going to be different if you are not a YEC than if you are.)

I'm engaging in dialectic, not rhetoric. I don't believe rhetoric has a place on this site, at least not from me. Since this is a site dedicated to intellectual curiosity, why don't you please present me with both?

> why don't you please present me with both?

If you are not a YEC, then the first thing I'm going to do is ask you why you think that cosmology and physics are different?

If you are a YEC then I don't need to ask you that question because I already know the answer. (It's because you have accepted the truth of the Bible as a foundational assumption. From this, the idea that modern cosmology is not science is a logically valid conclusion.) Instead, the first thing I'm going to do at this point is to ask you why you are trying to conceal it.

Also, if you are a YEC, I would be interested to know if you were surprised that I was able to correctly guess this.

Re: The universe is expanding faster than expected

#73

Post by mathattack »

simonh wrote: post #61
kiba wrote: post #12

Earlier quoted context omitted.

What does it mean to not pass the great filter? Humanity or their successor stop existing?

There are multiple explanations for why the sky isnt lit up with radio and laser signals from advanced civilisation. The great filter is one explanation, that there are existential crises or threats that wipe out most civilisations or cause them to collapse to subsistence level. Nuclear war, biological weapons, ecological collapse, paper clip maximising AI, etc. I once ran a Traveller RPG exploration campaign where o…

I hope you snuffed them out before they took over the universe.

The surprisingly addictive game is below.

https://www.decisionproblem.com/paperclips/

Re: The universe is expanding faster than expected

#74

Post by User23 »

hypertele-Xii wrote: post #36
h2odragon wrote: post #34

Time runs slower when you're young; but then as you age there's less time in each day. Perhaps it's the same for everything else that experiences time, from us to galaxies and universes.

This is because information in your brain is constrained by physics. It takes tangible time for signals to travel between neurons. When you're young, you're small, and the distances are shorter. As you age, you grow in size, and the signal length grows also. Thus as you grow you literally think slower; though hopefully, more effectively (wisdom). Your perception of time changes accordingly.

Action potentials travel significantly faster in adult human brains than in children because for the latter the myelin sheath isn't yet formed.

Re: The universe is expanding faster than expected

#75

Post by User23 »

strbean wrote: post #68
layoutIfNeeded wrote: post #44

Earlier quoted context omitted.

What you wrote has no basis in reality whatsoever. In fact, nerve conduction is slower in children than adults due to underdeveloped myelination.

My flippant guess would be that time perception changing with age would be related to the NMDA receptor. NMDA receptor function decreases with age[0]. My personal anecdotal experience with NMDAR antagonists is that it feels like the `Turbo` mode on old IBM compatibles[1] -- i.e. downclocking. And the slower you process, the faster the world seems to move around you. [0]: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC3…

My even more flippant guess would be that adults drink more alcohol than children.

Re: The universe is expanding faster than expected

#78

Post by fouc »

woko wrote: post #8
eloff wrote: post #6

Earlier quoted context omitted.

I appreciate your optimism. I tend to be optimistic about the future myself. But there is no law of the universe that everything will work out ok. Only if we make the right decisions as a species and we don't get unlucky. I'm quite apprehensive that the great filter lies ahead - that technology accelerates too rapidly compared to our wisdom and we end up nearly destroying ourselves. We're getting the ability to progr…

I think it was a joke about zero Kelvin.

Zero entropy

Re: The universe is expanding faster than expected

#79

Post by ineedasername »

grey-area wrote: post #9
eloff wrote: post #6

Earlier quoted context omitted.

I appreciate your optimism. I tend to be optimistic about the future myself. But there is no law of the universe that everything will work out ok. Only if we make the right decisions as a species and we don't get unlucky. I'm quite apprehensive that the great filter lies ahead - that technology accelerates too rapidly compared to our wisdom and we end up nearly destroying ourselves. We're getting the ability to progr…

I believe the OP said 0K, not OK. There may not be a universal law which says everything will be OK, but there is one which says everything will be 0K in the end.

nearly 0k

Re: The universe is expanding faster than expected

#80

Post by User23 »

lisper wrote: post #72
User23 wrote: post #31

Earlier quoted context omitted.

I'm engaging in dialectic, not rhetoric. I don't believe rhetoric has a place on this site, at least not from me. Since this is a site dedicated to intellectual curiosity, why don't you please present me with both?

> why don't you please present me with both? If you are not a YEC, then the first thing I'm going to do is ask you why you think that cosmology and physics are different? If you are a YEC then I don't need to ask you that question because I already know the answer. (It's because you have accepted the truth of the Bible as a foundational assumption. From this, the idea that modern cosmology is not science is a logical…

If I were not a YEC, then I'd think cosmology and physics are different because physics is a laboratory science where depending on our budget we can do anything from roll balls down inclines to produce quarks while with cosmology we have absolutely no control over conditions and can only make believe we do by sampling in a way that necessarily is corrupted by our biases. And the amount of data to sample from is plenty ample for unconscious bias to have a significant effect.

If I weren't a YEC, I would focus more on issues with radiocarbon dating and the assumption and not the observation that carbon isotope ratios are constant over the history of the Earth and ignore cosmology entirely. In fact I'm not clear on what YEC has to do with cosmology at all, it strikes me as being outside the scope of the arguments I've seen on the subject.

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