As a layman it always amazes me when reading such news that what we see now actually _happened there_ n years ago (in this case: 3.5 billions years ago). Not that it matters, but it is mind boggling nevertheless.
Those galaxies are magnified to the point where they are visible by another, much closer galaxy cluster, which is only 3.5 billion light years away.
1. these photos have been traveling for 13.5 billion years, just to meet their fate smashing into the JWST.
2. how many photons must have been emitted, that a sphere 13.5 billion light years in radius can still resolve the image.
Still amazing to think about though.
The radius of the universe is irrelevant.
Layer on yet another high improbability, that photon-ant collision just so happened to send it directly toward me. Wait, not just me, but the tiny little pupil in one of my eyes!
Tremendously large numbers and crazy minuscule fractions can be found in your backyard. Don't even need to leave the Solar System.
Time, life, death, technology, and everything will be just so unimaginably alien. It will be basically impossible to have a normal linear view of time when it's violated constantly, even though your body itself will yet still almost certainly be insistent on linear time - and steadily marching towards its expiration date. Even evolution itself will be weird. Humans over millions of years will probably scarcely resemble ourselves today, yet you'll regularly have 'old' species humans regularly reintegrating with 'new' ones?
Such a bizarre reality we live in, unless perhaps somehow the views we have today end up being as quaint as those of times past.
We already have enough problems with conflicts arising between people born in either side of an imaginary line. How will that work with humans born in different eons?
Aren't all rockets relativistic? In the sense that "there's no inherent reason", I take it to mean "near to c", for some value of "near". that is, it's a "relative" term.
What relativity does is change things in a way relative to who's observing. From your perspective distances would begin to physically contract, time everywhere else would begin to accelerate, and things would probably start looking a bit odd. But you could keep hitting that button to your heart's content, and continue going faster and faster.
By contrast for a relatively at rest observer, looking at you, they would see your relativistic mass start to approach infinity as you approached the speed of light. And so they would see you slowing down (as accelerating an infinite mass object would be impossible), and the movement of time for you (relative to them) would begin to slow dramatically, hence why time for them (relative to you) seems to accelerate dramatically.
The calculations for relativistic rockets are quite remarkable [1], because it's an exponential system. For instance, here are some times it'd take you to travel to various points in a typical relativistic rocket that continues to accelerate at 1g (you go half way to a target at 1g, and then half way in reverse):
- Proxima Centauri - 4.3 light years away - 3.6 "real" years of travel
- Vega - 27 light years away - 6.6 "real" years of travel
- Center of our galaxy - 30,000 light years away - 20 "real" years of travel
- Andromeda Galaxy - 2,000,000 light years away - 28 "real" years of travel
With a relativistic rocket, if you wanted to see what the end of the universe looked like in a single human lifetime, you could. It's really really weird. So basically a relativistic rocket is more about creating a rocket that can just keep accelerating for years at a time, rather than reaching any specific speed. They're certainly similar in effect, but framing it in terms of years of acceleration makes it a pretty well defined problem.
[1] - https://math.ucr.edu/home/baez/physics/Relativity/SR/Rocket/...
Why do you think humans will stage undergo the aging process at that time? With that level of technology, the idea that humans won't have cured the disease we call "aging" seems absurd.
>Even evolution itself will be weird. Humans over millions of years will probably scarcely resemble ourselves today, yet you'll regularly have 'old' species humans regularly reintegrating with 'new' ones?
Humans haven't been evolving due to natural selection for thousands of years. Any changes in humans in the future will be due to genetic engineering.
Natural selection doesn't require you to be out in the wild fighting against the elements, it's no different than what's happening socially at an extreme level today. Certain groups have certain characteristics driving them to have large families. Others lack those characteristics. Whatever these characteristics may be, they're going to be far more dominant in the generations that follow ours. It's evolution.
There are multiple species in the wild right now that disprove this. Biology doesn't require aging.
>And to reject natural selection, especially at a time like now, is something I find even more odd.
You seem to not understand exactly what natural selection is and its role in adapting an organism to its environment.
"Lobsters grow by moulting which requires considerable energy, and the larger the shell the more energy is required.[28] Eventually, the lobster will die from exhaustion during a moult. Older lobsters are also known to stop moulting, which means that the shell will eventually become damaged, infected, or fall apart and they die.[29] The European lobster has an average life span of 31 years for males and 54 years for females." [1]
As for evolution, we all learn about Darwin's finches, and so people think of it in terms of things like a bird gradually evolving a more adaptive beak for what's available on an island. But natural selection and evolution is not about evolving your body to fit your environment, unless that would provide a benefit to fertility. If there was endless food on the Galapagos islands for said finches, then said beak would provide 0 fertility benefit and would not, in any way, be evolutionarily selected for.
The reason we, as a species, exist today is because higher intelligence enabled higher successful fertility rates. It's not because intelligence is inherently better. So, for instance, if it turns out that lower intelligence, in modern times, is more productive for fertility when we as a species will gradually become less intelligent. All evolution cares about is fertility, and whatever it takes to achieve it.
[1] - https://en.wikipedia.org/wiki/Biological_immortality#Lobster...
Why do detractors always think that biological immortality shouldn't require some kind of external treatments occasionally, and then argue from that assumption? Most people don't expect their car to work forever without new fuel, maintenance, repairs, etc.
So you're left with a mish-mash primarily of weird little microscopic asexually reproducing creatures, that have essentially nothing in common with advanced lifeforms. And as more evidence on these species is collected, it invariably trends towards the rejection of biological immortality rather than the confirmation of such. For instance the hydra once thought ageless, has been shown to decrease asexual reproduction as it ages - clearly demonstrating an active and detrimental aging process.
The entire field is even more dysfunctional with the obsession on telomere length, even though we know that telomere length is correlated with aging, and not causal. Lobsters are an example, as they actively regenerate their telomeres, yet age and die. As are mice - where telomere lengths remain roughly the same as they age, and die.
Nobody wants to die, and so it creates a strong motivation for us to set aside our logic and rationale, and imagine we might live forever. I simply refuse to do that. I believe it will lead to a happier and healthier life for myself than for a man like Ray Kurzweil who will certainly die in the coming years, after spending a lifetime trying to convince himself he could live forever, using logic he could trivially refute in 5 minutes if he actually wanted to.
The idea that it's physically impossible is simply ridiculous, and a religious belief. We're able to effectively be immortal now, simply because of reproduction: cell lines continue forever, just not in the same organism. Can we achieve this anytime soon? Perhaps not. But to say it's impossible is silly, it's like saying you can't transmute elements (like lead to gold), when it's been done countless times in stars. Of course, there's a way, but it might involve very advanced tech like nanomachines and genetic engineering.
I think this was an issue, even in the distant past. The Fountain of Youth would have been being 'thought up' about the time mankind was discovering all sorts of strange wonders in the world, like what happens if one chews on the bark of the willow tree. You will feel a bit odd, but all of your pain and discomfort will just magically fade. Of course that is where Aspirin comes from. And similarly for all other sorts of other seemingly magical discoveries. In this context it's easy to convince oneself that even the waters of immortality are just one more discovery away, but really there's no reason to really think it was, or is.
However, the idea that aging is somehow necessary is purely a religious belief. There's absolutely no physics-based reason why it has to be this way.