
How Can a Star Be Older Than the Universe? - QuitterStrip
https://www.space.com/how-can-a-star-be-older-than-the-universe.html
======
ajay-d
GN-z11 is a galaxy that's 32 billion light years away. Here's the note from
wikipedia:

At first glance, the distance of 32 billion light-years (9.8 billion parsecs)
might seem impossibly far away in a Universe that is only 13.8 billion (short
scale) years old, where a light-year is the distance light travels in a year,
and where nothing can travel faster than the speed of light. However, because
of the expansion of the universe, the distance of 2.66 billion light-years
between GN-z11 and the Milky Way at the time when the light was emitted
increased by a factor of (z+1)=12.1 to a distance of 32.2 billion light-years
during the 13.4 billion years it has taken the light to reach us.

[1]
[https://en.wikipedia.org/wiki/GN-z11#Notes](https://en.wikipedia.org/wiki/GN-z11#Notes)

~~~
namirez
Also, despite the age of the universe (13.8B years), the diameter of the
observable universe is 93 billion light years. That's because the universe
expanded (and probably still is expanding) faster than light.

~~~
laurencei
Can you ELI5 - how can we observe something 93 billion light years away, if
the light has only been traveling for 13.8B years? Shouldnt the "observable"
distance be the the age of the universe?

~~~
devnulloverflow
Your intuition that there is an limited observable distance because is
correct. But because of the expansion, that limit is bigger than
"speed_of_light * age of universe" .

I don't know enough General Relativity to give a solid explanation. But here
is a rough over-simplification: Imagine you've spent the last 5 seconds
blowing up a balloon, but there is an ant walking on that balloon, starting
from a marked spot.

In the 1st second, the ant moved 10mm. But in the next four seconds you blew
up the balloon, so that 10mm of rubber is now 70mm long. The total distance
from the ant's starting mark to her end-point can now be well over than 70mm,
even though she only walks at less than 10mm/second.

As the ant, so the photon.

~~~
techas
If space works as a balloon then the growth happens in all the volume of the
universe (not just on the “boundary”). Is that how it works? Doesn’t that
imply that we are getting “bigger”?

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ggggtez
No. Just because space is expanding doesn't change the electromagnetic forces
holding you together.

~~~
ivoras
But just thinking of the electromagnetic forces in terms of what is required
from them to keep matter together in the context of that same matter
effectively expanding faster than the speed of light is... at best weird.

~~~
Filligree
The speed of expansion depends on the size of the object. Human-scale things
aren't expanding at the speed of light; you need to get to larger-than-galaxy-
cluster scales for that to happen.

(In fact space inside galaxies isn't expanding at all, only space between
galaxies. But I digress.)

------
novia
Short answer: it's only older than the universe if you ignore the error bars
of the estimate.

~~~
TallGuyShort
And it's only older than the universe if you assume the Big Bang was the
beginning of the universe, which there's really no evidence to suggest. Pretty
much everything else in the universe all seems to suggest that it all
originated from a similar point in time and space and that it rapidly expanded
outward. Okay. But what was going on in this particular space back then is
completely unknown, so... could there have been some stars forming already
from matter that wasn't part of the Big Bang? Why not?

~~~
sorenn111
Quark Gluon Plasma (observed at the RHIC), at really early in the universe
there was too much temperature and pressure to have stars or even atoms. At
least that's my understanding.

~~~
TallGuyShort
Yes but Quark Gluon Plasma existed immediately following the Big Bang. We
arrive at the Big Bang by reverse engineering lots of evidence we see in the
universe. What evidence is there that nothing else currently inside the bubble
of the observable universe could possibly have been there, very far away from
the Big Bang, at the time of the Big Bang?

I don't see why I'm being down-voted because as of yet no one has answered
that question. I'm not saying the Big Bang didn't happen. I'm saying we have
no observations that give us any confidence we'll never encounter something
that wasn't part of the Big Bang. This star actually pre-dating the Big Bang
is extremely unlikely, I agree. The simpler explanation is the uncertainty in
it's age estimation. But equating "the observable universe" with "stuff that
originated in the Big Bang" is an assumption we simply don't have much
reasoning for, other than we haven't seen much other stuff. But then... we
also don't see many stars this old.

~~~
semi-extrinsic
All the evidence suggests that Big Bang did not happen at one identifiable
point. Instead it happened everywhere simultaneously. So there is no place in
our universe "very far away from the Big Bang".

~~~
ergothus
Not the above poster, but I want to understand. I have half-understood
thoughts that conflict with each other. Any help showing where I misunderstand
is appreciated, but this is probably a failure of my brain to be able to cope.

* All space was contained in the big bang, so "everywhere simultaneously" makes sense from that perspective.

* ...but the idea that space is expanding implies an outer "edge" (, which doesn't make sense if space isn't infinite. (or is it infinite, and just getting "more" infinite, in the way that the space on the number line between 0 and 1 is infinite, but "less" infinite than between 0 and 2?

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crooked-v
> ...but the idea that space is expanding implies an outer "edge"

No, it doesn't.

For example: consider an infinite number of marbles in an infinitely long
line, all of them are touching each other.

Now, get an infinite number of helpers stationed along the infinitely long
line, and have them all move the marbles in front of them to the right and
stagger them out in the process, so that there's now an inch between each
marble.

You now have an infinite number of marbles an infinitely long line, but it's a
_longer_ line than it started out, because there's now an inch between all the
marbles.

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brutt
You will need infinite amount of energy to insert spaces between these
marbles. Can you point us to source of this energy?

~~~
crooked-v
The theory of the Big Bang (or at least the variants with an infinite
universe) includes infinite energy as part of the initial singularity.

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alan-crowe
We've been here before, with stars older than the age of the universe. Last
time, we thought that there was only one kind of Cepheid variable. This lead
to underestimating the age of the universe. Later, astronomers realized the
nearby Cepheid variables (used for calibrating the period/luminosity
relationship) differed systematically from the bright Cepheid variables that
we could see in distance galaxies.

Understanding the difference between Type I and Type II Cepheid variables lead
to a greater estimate for the age of the universe, resolving the difficulty.
So I expect some interesting astronomy to come out of tracking down the cause
of this discrepancy.

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svdr
A great cosmology faq, answering this and a lot of other questions:
[http://www.astro.ucla.edu/~wright/cosmology_faq.html](http://www.astro.ucla.edu/~wright/cosmology_faq.html)

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amp108
> It's composition meant the star must have come into being before iron became
> commonplace.

Hypothesis 1: the star formed in a way that did not involve or produce a lot
of iron.

Hypothesis 2: the star is older than the universe itself.

 _Clearly_ , hypothesis 2 is the more likely.

~~~
hypothesis-3
Hypothesis 3: Due to inherently incomplete information, our understanding of
the age of the universe is not yet perfectly correct, and the universe may be
older than current models and theory.

Strap yourselves in folks, maybe The Big Bang is but one event woven amid a
deeper tapestry of events, significant only in its capacity to occlude deeper
periods of time.

It should surprise no one that we might be wrong about some centralized, focal
aspect of the universe, given how wrong we've been before, about things we
assumed to be the center or origin, previously.

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madrox
This remind me of a similar story with the age of the earth and the solar
system. Scientists using new methods were starting to discover that Earth was
far, far older than originally predicted...so old, that it seemed to predate
our sun. It turns out it our estimates of the solar system's age were wrong,
but it took some time to figure out why.

I imagine something similar is going on here. The article mentions that once
they got an age older than the universe, they started looking at how to make
the star younger...finally by acknowledging the margin of error in estimates.
That sounds like bad science to me.

~~~
progval
> The article mentions that once they got an age older than the universe, they
> started looking at how to make the star younger...finally by acknowledging
> the margin of error in estimates. That sounds like bad science to me.

Later (in section "Taking a closer look at the age of the universe"), they
tell that your theory is also being looked into.

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hirundo
I think, by Occam's Razor, the most likely explanation is that there's a
skybox surrounding the solar system that Voyager 1 may run into any day now,
like Truman Burbank at the end of The Truman Show. It seems to be a more
parsimonious explanation of the available facts that we're looking at the
result of a super duper planatarium projector, as opposed to an actual vast
and frequently inexplicable universe.

~~~
crooked-v
If you're going in that direction, you may as well say that the universe is a
simulation. Planck limits on measuring time and space as a continuum would
pretty useful for putting a hard cap on required rendering resources per
volume of space-time...

~~~
wruza
Simulation doesn’t have to obey the rules. For non-scientists it is enough to
“tell” them how it works without actually rendering it, cause they’ll never
check. For scientists, you have to make their brain believe that all is
consistent with complex computations all the way down.

Imagine that you know physics and math very good. But then simulation suddenly
fails due to segfault and you realize that all your knowledge was just a
gibberish nonsense and your work sessions and discussions were dream-like
experience. Otherwise it was just a pretty dumb 3d simulation slightly better
than a modern AAA game.

Edit: I mean, a simulation argument opens a huge can of worms, if you consider
the perspective of a lazy simulation developer them-self.

~~~
simula
While a simulation doesn't have to obey the rules, any given simulation is
likely to resemble a system that does adhere to rules, since a simulation is
indeed simulating something else.

Even if some external observer can pause, rewind, intervene and violate rules,
the reason a simulation exists is to model something else.

This "something else" will have some kind of rules, and the goal of the
simulation will be similarity to the actual realm external to the simulation.

Meanwhile, a lazy replication of a model by an unmotivated author would likely
impose finite quantities upon scales of interaction, since a simulation won't
be able to recreate a real time version of something larger than the external
reality itself.

We wouldn't notice a lagged simulation that tries to consume its footprint,
but it's probable that an artificial creation would impose caps on aspects of
a system to prevent runaway reactions that produce useless simulations. To us,
those sorts of limitations would resemble extra physical laws, and while
incontrovertible to the simulated entity, such limits might confront intuition
in strange ways.

------
egdod
I was hoping for some weird time-bending effect from general relativity, but
no, it’s just that the ages are within each other’s error bars.

~~~
dmix
Still an interesting read and thought experiment.

------
drclau
This reminds me of Iain Bank’s Excession. Great book, strongly recommend it.

~~~
cpeterso
The relevant bit from Excession is the discovery of a mysterious entity that
is 50x older than the universe.

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ShamelessC
What's the explanation?

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cgrealy
Without giving too much away, it's not from this universe.

You really should read it, it's one of the best books in the culture series
and Banks was a phenomenal writer.

It also contains the Affront, a species that are almost comically awful and
coined the term "outside context problem":

"The usual example given to illustrate an Outside Context Problem was
imagining you were a tribe on a largish, fertile island; you'd tamed the land,
invented the wheel or writing or whatever, the neighbors were cooperative or
enslaved but at any rate peaceful and you were busy raising temples to
yourself with all the excess productive capacity you had, you were in a
position of near-absolute power and control which your hallowed ancestors
could hardly have dreamed of and the whole situation was just running along
nicely like a canoe on wet grass... when suddenly this bristling lump of iron
appears sailless and trailing steam in the bay and these guys carrying long
funny-looking sticks come ashore and announce you've just been discovered,
you're all subjects of the Emperor now, he's keen on presents called tax and
these bright-eyed holy men would like a word with your priests."

~~~
jackgavigan
You left out the best bit!

"An Outside Context Problem was the sort of thing most civilisations
encountered just one, and which they tended to encounter rather in the same
way a sentence encountered a full stop."

Shades of Douglas Adams there...

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inetknght
Why can't the star be older because of relativity? I imagine that,
particularly in the early universe while everything was nearer to everything
else, relative background gravity was higher (and thus relative time) is
different than now. Would the star not age at a different rate if it's a
remnant from violent beginnings of the universe?

~~~
Ancalagon
I think, if I understand your question correctly, that a star couldn't age
more, only less, from our perspective.

EDIT: I could be wrong though, and additionally I believe the star being
referenced by the article is actually in a similar reference frame so
relativity likely isn't the answer anyways.

~~~
AnimalMuppet
No, but _we_ (our planet, stuff in our vicinity) could age less.

What we'd need is most stuff (that gave rise to most stars and most of our
measures of the age of the universe) to be in a higher-gravity region compared
to the star in question. It seems unlikely, but I suppose it's possible...

[Edit: I thought you were talking about GR time dilation due to gravity. A re-
read shows that I may have been in error.

Also, for a star 190 ly away, _any_ relativistic explanation, either special
or general, is probably wrong.]

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yongjik
I don't think there's such a concept as "higher-gravity region" in modern
physics, unless you're thinking about "in the vicinity of a giant star, black
hole, or something equally massive."

However, if most of the known universe is sitting next to a gigantic mega-
blackhole (or enough of them to cover the whole sky), then surely we would
have noticed by now...

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inetknght
> _I don 't think there's such a concept as "higher-gravity region" in modern
> physics, unless you're thinking about "in the vicinity of a giant star,
> black hole, or something equally massive."_

I think at the beginning of the universe, there might be a lot of regional
discrepancies. They might even just be "temporary" regional discrepancies from
gravitational waves due to the inherent nature of the universe growing and
everything still crashing together.

~~~
Filligree
The cosmic microwave background tells us there were practically no
discrepancies at all, actually. Not too surprising, since at the densities
back then even a small local fluctuation would easily have become a black
hole.

The very early universe wasn't perfectly uniform, but it was really, _really_
close.

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thrower123
The most likely answer is that either the measurement or the theory is wrong.
Both are probably about as likely.

------
KingCobra
It reminds me of the same question asked in this book, "The Birth of Time: How
Astronomers Measured the Age of the Universe" by John Gribbin. The bottom line
was that the calculations always have some approximations, which can throws
off a number by a large factor.

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bena
Did anyone read the article and get a feeling it was mostly just a fluff piece
describing how we're refining our ability to tell the ages of stars?

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imvetri
Start over space theories all over again. Lets not build our assumptions on
previous generation findings.

Only if we take path of how the previous geniuses went through we will have a
flawless exploration. Instead of doing that, if we work on someone else's
work, its like eating someone else's recipie and trying to remake the tase of
it without understanding the ingredients in it.

------
mirimir
Given the norm for question titles, the answer must be "It can't." Also simply
based on what a universe is.

What we have are just different estimates for the age of our universe. And
none of them involve simple measurement, obviously. So the challenge is
finding the artifact(s) that generate the disagreement.

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accnumnplus1
Does the microwave background come from the centre of the universe where the
big bang was; and the light from stars on the far side, flying in the opposite
direction to us, take longer to reach us than the microwave background does?

~~~
turndown
The Big Bang happened everywhere in the Universe, at once. Our CMBR is coming
in from all directions, at all times, as more distant locations(eg further
away from us at the start) finally reach us.

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johnklos
I would REALLY love to read this, but space.com is one of those asshole sites
that wants to take a gigabyte of memory (I'm not joking) and wants a full 30
to 45 seconds of CPU just to load the page.

~~~
zarriak
It loads almost instantly without javascript. I can understand not using
adblocking but why are you complaining about loading times when not using
umatrix or noscript?

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blackflame
What came first, the photon or the electron? Can a photon be emitted without a
change in energy state?

I’m new here, so instead of answering questions is the protocol just to
downvote?

~~~
yosefzeev
Oftentimes. I gave you an upvote just because sometimes around here you will
get downvoted because the gods of zeitgeist decide it must be so.

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Ancalagon
wow what an interesting article. Finding not one, but multiple stars that are
much older than the predicted age of the universe means something is likely
very wrong with one of our theories: dark energy, star aging, or using the
cosmic background as a measure of the universe's age.

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exabrial
I was thinking maybe it was traveling a large fraction of c and there was a
relativity thing going on

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tcarn
HN is making me wish I studied astronomy, such cool stuff.

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cgrealy
Nonsense, the universe is only 6000 years old....

and it's a Libra.

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eximius
Okay... This implies the light was stretched along with the space, right?
Because otherwise, the photons would just... Never reach here if space between
us and the light expanded faster than c.

~~~
paulmooreparks
Correct. See...

[https://en.wikipedia.org/wiki/Horizon_problem](https://en.wikipedia.org/wiki/Horizon_problem)

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dfilppi
Which universe?

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ReptileMan
A question - how common are such old stars? Because it is right in our
backyard. 190 light years away are nothing. And if those stars are rare - that
makes our neighborhood unusual - we have life and some of the oldest object in
the universe in almost the same spot.

~~~
bArray
Almost everything of interest essentially happens in our backyard because
that's the place we can see with the most detail. It's a little like looking
out at the Universe and coming to the conclusion that we're in the middle of
it because the "edges" are all around us.

Even if this was rare and there happened to be tonnes of very old stars only
close to us, this could again be coincidental, especially if intelligent life
is more common than we currently know.

~~~
4ad
This is precisely true, only very small stars last very long, and small stars
are very dim. All the old stars that we see must be very close. The bright
stars that we see that are far away only live for a few million years.

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lottin
Here we go again... "scientists would look at the ripples in the fabric of
space and time". Am I the only one who finds this expression very confusing?
What fabric? There is no fabric. Space and time are coordinates. They do not
exist physically at all. There cannot be a fabric of space and time.

~~~
tiborsaas
It's a metaphor to help humans grasp it better. Space and time does exists
physically.

Does a shortest path between you and your workplace exists that you can
traverse? Is it a straight line? No, it's not, but there's one path that you
as a being can walk along physically. The buildings, roads, obstacles force
you to diverge from the ideal straight line. That's another analogy of what
space & time is. Fabric is just shorter.

