Has JWST shown the Universe is TWICE as old as we think?!
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- čas přidán 2. 05. 2024
- Go to brilliant.org/drbecky to get a 30-day free trial and the first 200 people will get 20% off their annual subscription. A new research study has come out claiming that to explain the massive galaxies found at huge distances in James Webb Space Telescope images, the Universe is older than we think, at 26.7 billion years (rather than 13.8 billion years old). In this video I'm diving into that study, looking at what model they used to get at that claim (a combination of the expansion of the universe and "tired light" ideas of redshift), how this impacts our best model of the Universe and the so-called "Crisis is Cosmology", and why I'm not convinced yet!
#astronomy #JWST #cosmology
My previous CZcams video on how JWST’s massive galaxies are no longer “impossible” - • JWST's "too massive" g...
Gupta et al. (2023; is the universe 26.7 billion years old?) - academic.oup.com/mnras/advanc...
Labbé et al. (2023; over-massive galaxies spotted in JWST data) - arxiv.org/pdf/2207.12446.pdf
Arrabal Haro et al. (2023; z~16 candidate galaxy turns out to be z=4.9) - arxiv.org/pdf/2303.15431.pdf
Zwicky (1929; "tired light" hypothesis raised for first time) - www.pnas.org/doi/epdf/10.1073...
JWST observing schedules (with public access!): www.stsci.edu/jwst/science-ex...
JWST data archive: mast.stsci.edu/portal/Mashup/...
Twitter bot for JWST current observations: / jwstobservation
The successful proposals in Cycle 2 (click on the proposal number and then "public PDF" to see details): www.stsci.edu/jwst/science-ex...
00:00 - Introduction: JWST's massive galaxy problem
01:48 - Our current best model of the Universe: λ-CDM
03:16 - The problems with λ-CDM and the "Crisis in Cosmology"
04:28 - Getting distance from redshift
05:13 - A new model of the Universe: a HYBRID of "tired light" and expansion of the Universe
06:25 - The history of "tired light" and why it was eventually dismissed (Tolman Surface Brightness Test)
08:18 - What Gupta (2023) have found
09:30 - The change to the calibration of redshift and distance (and the new age of the Universe)
10:02 - What other problems does this new model help solve?
11:07 - The observational evidence that this new model ignores...
12:39 - How else do we explain JWST's massive galaxy problem? Universal IMF issues
14:35 - Outro: the legacy of JWST
15:23 - Brilliant
16:46 - Bloopers
Video filmed on a Sony ⍺7 IV
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👩🏽💻 I'm Dr. Becky Smethurst, an astrophysicist at the University of Oxford (Christ Church). I love making videos about science with an unnatural level of enthusiasm. I like to focus on how we know things, not just what we know. And especially, the things we still don't know. If you've ever wondered about something in space and couldn't find an answer online - you can ask me! My day job is to do research into how supermassive black holes can affect the galaxies that they live in. In particular, I look at whether the energy output from the disk of material orbiting around a growing supermassive black hole can stop a galaxy from forming stars.
drbecky.uk.com
rebeccasmethurst.co.uk - Věda a technologie
Maybe, it just feels twice as old. I can relate to that.
Relatable.
I'm 23.8±10 years old. I'll tell you more, once more evidence comes in.
Brilliant.... 😅😅😅
@@roberthoey2121 0
Your comment and the subsequent thread of replies have made my day, I too can relate lol
I like that you add a little portrait of individual authors on the papers that you show. I know its not a big thing necessarily, but putting a face to the name kinda grounds it in my mind. I know these are real people, but seeing a face makes it feel more real... if that makes any sense. Also I imagine the authors like it as well. Adding a bit of humanity to the cold science.
Considering the race to throw together AI compiled fluff in articles now it's more important than ever to appreciate the creative contributions of real people.
Yes, Ive seen a few science-related channels doing this lately and I really think its a great idea.
@@HermanVonPetriYou really had to shoehorn in a point about AI, huh. I'm so sick of seeing arguments over AI in completely unrelated threads. We get it, you hate/love AI, your opinion is heard. 🙄
Yeah, facial recognition is one of our strongest visual capabilities. It really does help form memories, to see the name and face together.
agreed!!! I feel that too
I love the fact that JWST is challenging our understandings of the universe, it is exactly what any great experiment is supposed to achieve.
actually it only challenges false belief. the universe is electric.
@@thephuntastics2920 In science there is no false belief, there is theory and failed theory. Science should not be a belief system.
@@rrmackay Currently a failed theory is what everybody mindless believe.
@@mahead that still isn't science, it just means public misconception.
@@corrinflakes9659 since that misconception is endorsed by academia, it makes science an ambiguous term
I appreciate people exploring all our options, if nothing else. I think these types of papers are extremely useful, so really glad they are getting made, whether right or not.
Even more so when it is a controversial topic many will oppose because it challenges a fairly common view. People forget that dark mater and all that only was invented to make all the models work somehow. So we likely just don't know it any better for now.
@@3komma141592653 specifically, dark matter is the difference between observed gravitational forces vs expected from relativity
Love that I can come here for actual science and data instead of sensationalized pop-sci garbage. Even PBS Spacetime is giving you shout outs! Never change Dr Becky!
Ironic that you brought up PBS cause they don't do what she does
@@drsatan7554 Is it actually even legal for PBS to do that? Isn't she considered a Crown servant for employment purposes?
@@erkinalp free use
@@drsatan7554 They dont, but they are still a great channel .
@@captainkirk4271
The great thing about research like this is that in attempting to refute it, someone could potentially be inspired to come up with a solution to one of those problems, or even a better model than lambda CDM. And thats really exciting!
Unfortunately, the most probable response is that the mass of those galaxies were overstimated. The bigger a star is, the bigger the ratio between its luminosity (observed) and mass (deduced) is also, and the consensus is that early stars were huge, but it’s still fuzzy on how much.
@@franck3279 That's easy to say and harder to prove. And thats my point. If someone wants to refute this paper they will need to look into those assumptions and attempt to actually disprove them. Which may turn out to be a heck of alot more interesting than this paper.
@@patreekotime4578 I agree with you too. Sadly it is possible that the "right" answer, whatever that may be and amongst the sea of wrong answers, may disagree with current thinking and be automatically treated with the usual skepticism while dubious results and variations that "agree" will continue to be lauded with very little refutement.
@@gonegahgah I dont think thats sad. It would be untenable if the entire scientific community jumped to accept every new theory before it is rigorously proven. The stauchness of conservative thinking within science just means that when new theories ARE eventually accepted, then we the general public can be assured that they have undergone the necessary scrutiny to be considered fact.
@@patreekotime4578 There not considered fact. Until all facets are "proven" they remain that way. They become the prevailing theory. Otherwise they would be called laws rather than theories. Extension of another theory is not proof. Like the ridiculous Hawking Radiation. Further, a lot of our theories do not explain the underpinnings and until they do they lack foundation. It's almost as if they are giving up trying to fathom that relegating it as unimportant. I certainly don't think they should accept every new theory. However they have to not shut themselves off from being wrong and that there may be a more accurate approach to finding the underpinnings. Unfortunately we a exceedingly locked more into group think rather than pre-bias free critical thinking. You can hear it in the language of these scientists, including our Dr Becky. Any data that contradicts is immediately spoken of as suspect with strong belief that it will disappear. Anything that agrees with current thinking is immediately embraced without any scepticism what-so-ever. Just take LIGO for example. They haven't released their data despite promising that they would. But still there are only a very few who question them.
Amazing as usual! I love the depth of the explanations and how you go through so many of the concepts to shed light on the information. Many articles I partially read in the past gave a dim idea of what's happening in the field and I now feel like I can get a much better idea how influential an article or paper is on the whole of astrophysics and cosmology.
A photon experience stretching instantaneously because the time stops for a photon?
It is absolutely insane to me that the idea that redshift could be due to both expansion of the universe AND tired light wasn't seriously considered before now. That's hardly a wildly outside-the-box idea. There has to be more to it than this.
Seriously! Too many physicist busy wasting their time with string theory I guess.
Scince about 1982 I have always thought the universe was about twice as old as we think it is...but not because of "tired light"....because people tend to just take measurements and wind the clock backwards to the moment of the big bang. One dimension to 4 dimensions of spacetime are assumed to "pop" into existance at the moment of the big bang. That seemed wrong. The dimension of time unfolded and continues to unfold. It was never a linear progression. Why does everyone assume that time was passing at the same rate at the beginning of the universe as it does now? We talk so easily about what happened fractions of a second after the big bang but we don't even attempt to conceptualize how time would be passing within that universe relative to being outside the universe.
And what boggles my mind is the same people who would say that rate of time passing, in the early universe relative to now, is trivial, are the same people who say time can slow down near black holes and that time difference is not trivial. Black holes are a simple concept and yet the universe is unfathomable?
Well like she said, there is not a single star out there that is older than the current estimates. So this doesn't give you much incentive to look in this direction, unless you can prove that there are older stars out there, or the measurement was not correct.
@@3komma141592653 Wow how do u know how old the stars is ? Have you been there and see when a star was born ? Any records ? Any evidences ?
Did someone get a sample from a star to estimate how old the star is ?
No ! After many years when Ai became more and more advanced and mistery are solved, i will came back here, and laught at your "scientiest" faces. With big joy i may add.
I will be very happy to laught at your faces about how WRONG you been.
It's Occam's razor again. Scientists tend to go for a single explanation if they can find one that appears to fit
For historical interest, in 1980, when I took my first astronomy class, the universe was 20 billion years old.
My teacher back in the 90s also told us that the age of the universe was first said to be around 24 billion, then down to 20, at some point to 18, then 16, then 14. He said "at some point, they'll end up near that estimate of that guy who added the dates of the bible and ended at somewhere near 6000 years."
@@kataseiko😂😂
Well, not exactly. They estimated a range of between 7-20 billion up until the Hubble Telescope helped narrow down uncertainty in the late 90's.
@@kataseikouh. No.
So, right now it is 20,000,000,043 years old.
The subject paper does not claim to be "the answer", but rather it is an interesting and useful "what if we try this, and this, and this" exercise. Science and scientists often become too confident in what they think they know. It's good when new data throws us a curve ball and causes us to question the unquestionable. Critical thinking and analyzing the effects of different "what if" theories is useful and should always be encouraged.
I agree. These days there is an assumption that just because it has been peer reviewed and published, then it must be correct and unassailable. Now, to get peer reviewed and published, one must not be too controversial either.
This is not how science should work.
Only by freely sharing (and being able to freely challenge) research and ideas, can the valid be sorted from the invalid and downright crazy.
Maybe the universe is double the current theorised age, maybe it isn't... but it's worthy of discussion either way, not instant dismissal.
For the most part, modern science is driven by quotas on publications, and by staying well inside the box, it's not how humans progressed in the past.
*Is* it useful though? It's leaping to propose a solution to a problem that hasn't even been confirmed to exist. While creating new problems.
Great analysis, thanks! Like you said, this is such a cool time to be watching these discoveries - there are so many ideas to explore. I love your balance of healthy skepticism and openness to new possibilities. This one does seem like a long shot, but an interesting way to at least try to explain the discrepancies.
Just ordered my copy of your Hardback Book on Amazon. Can't wait to read it!!! Please keep up the great video's!!
What is amazing about living in this time compared to Hubble's discoveries in the 1920s-1930s is that we have science communicators like you who can and do reach others who would otherwise be unable to access/understand the new knowledge. Thank you for being generous just for the sake of letting us understand.
@@kevinn3051they meant the person, not the telescope
How exactly would they have communicated it to you in the 1920s?
@@richardevans560 newspapers, books and soon radio
@@richardevans560There was no easy to access mass media.
In the 1920s it was mainly Printed paper, radio, going in person to talks and meetings(which required finding out through printed paper or word of mouth. There was also educational film.
But non of those were as easy to access as the internet and CZcams since we carry those in our pockets 24/7
@@richardevans560 By scientific papers I guess.
Thank you! I've been waiting for someone to break this down and not just jump to the conclusion that every other headline does!
Spacetacular summary indeed
I really enjoy your explanations and comparisons involving cosmological hypotheses. I took two years of physics in college, and have done reading in astronomy, etc. ever since.
My math stopped at analytic geometry, but I still appreciate your discussions. Keep educating us!!!
In my journal club I often ask my group members to look at your videos. MOND paper review was one of thoese. Thank you so much.
Only 100 years ago we were still arguing about whether there was more than one galaxy. I think we've been too presumptious in thinking we have everything figured out bar the minor details for some time now.
Oh no no. We've got it all down. We are God after all.
@@dayceem who told you how do you know? Did you read the CIA document stating that humans are nothing but energy gods, but I know that’s where you got it from.
Well whats fun about space is that we can never know if we are right at all only for basic stuff, i mean this is what we can see so far using the most advanced telescope built(jwst) we dont even know how big space is
Totally agree yes, tho I stay away from people saying these kinds of things cause it attracts a lot of crackpot scientists 😅
Spot on, I agree fully. It hubris to keep giving us this nonsense as gospel.
I’ve believed the universe to be 13.8 billion years old all my life. I’m now 64, and this really blows my mind and I’m not sure I can cope. I also really miss Pluto as a planet. Shakes me to the core.
Pluto is a planet if you want it to be. It is a definitions game. The new definition doesn't invalidate the old one and you simply choose to follow that or another.
I'm now 66 and have always believed that our current models of space always tend to be over turned when we build telescopes more powerful then the previous one.
@@barongerhardt Thinking pluto is a "planet" is as idiotic at thinking a whale is a fish. Get over it already.
It's so rude when scientists refer to Neptune as the last planet in our solar system. Pluto is a dwarf planet, and deserves respect!
@@KuK137well it fits 2/3 of the planet requirements, it just fails to have its moon in an orbit, instead they orbit one another. So...
Thanks for taking the time to explain! Helped a lot
I love physics partially also because of your thank you Dr Becky for this free content!
The great thing about science is that even a paper that's considered incorrect after more work on the subject is still valuable because it's encoraged other work that may show other results or even spawned new lines of research that advance understanding . There's also a part of me that thinks it's funny that everyone was saying how JWST would change the way we think about the universe and when it does that a bunch of scientists go " erm ............ Naa " lol
Or at least "erm... Need more data"
@@MrSJPowell You can never have enough data .
How do people not question dark matter, whose only evidence is that our calculations for gravity/mass keep turning out to be wrong, but you do question a model that actually works and has evidence from JWST that it could be right? If this model fit with the current paradigm then this doubt would not be present and people would have accepted it without question. This is the problem with science in the modern era. It's all about furthering the current paradigm and not true discovery, if that discovery doesn't fit with how modern science believes it to be. The egos and the aggrandization of knowledge of the current paradigm is turning science into the catholic church of old
@@la7era1u54 People do question dark matter. That's the whole thing with science , everything is questioned . The older universe theory was born from questioning the standard view and that theory is being questioned in turn. In the words of one of the greatest scientists of the 20th century , " That's all science is , it's best guess "
@@la7era1u54why do you think people don't question dark matter? There is a video about the doubts it raises on this channel itself. It's probably the topic that incites the most scepticism.
A great post that exemplifies the value of skepticism and accounting for uncertainty. The best part is how JWST stimulates thought. Dr. Becky has cemented her role as my goto inspiration for astrophysical reasoning.
While most if it I don't understand, I love the in depth explanations and all while having a cuppa tea. 😊
Way back in the late 90's I was getting my degree in physic and the whole acceleration of the expanding universe was crushing the theoretical guys. I was a engineering physics major so never really got deep into the cosmology, but I recall one of the proposed "fringe" theories was that the speed of light was slowing down proportional to the inverse of time cubed. (basically the idea was that the universe wasn't accelerating but the meter stick we measured it with was getting shorter) I don't recall the exact equation at the time, however, I seem to recall that it matched the supernova data and would explain the young hot sun and lunar regression mismatch (sedimentary data vs laser measurement). I took my degree and left physics to become a normal engineer and lost touch with all of the in's and outs of this sort of thing. Obviously that never took off of one reason or another. Anyway any thoughts if one of these older ideas that got thrown to the sideline in favor of dark energy might have a better solution.
Or the expansion might be caused by infinite space filled with matter we can't see because it's too far away but an infinity of time has allowed the gravity of that infinite matter to act on our local collection of galaxies. The other option is to believe that space has an edge that our future "starships" will bump into. Yes, silly, but so was sailing off the edge of a flat earth.
“Space is hard, words are harder”, basically my life motto
Did you mean 'difficult'?
And I'm the hardest
And never forget that the key word in any ’a new study ...’ headline is ’a’.
Does Spacetime have elasticity...? 🤔
Do you like math numbers (not letters)? I enjoy this channel because of her down to Earth way of explaining everything to us. Keep trying and keep watching.
So happy for you that you get to participate in the JWST era, and so thankful you take the time to bring us along for the ride. This was a great episode.
I'm using this amazing comment: Each new telescope will double the "age" of Universe. No beginning, no end! Only more money for scientists(space watchers & content creators) to keep us entertained.
All the more reasons for scientists to document and video their thoughts during this beginning of JWST.
Science at its best. Thank you for this video!
"Space is hard, words are harder" - Dr. Becky
This should be immortalized!
It staggers me to think that there may be beings in these galaxies billions of light years away, at this moment, looking at our Milky Way and saying it is 28 billion or 13.8 billion years old....but has "too many stars"....and debating how "young" galaxies like ours must be near the beginning of the universe!
This channel and Anton Petrov both put out videos with extremely interesting but also very suspect findings in the last few hours. Both make great content.
I agree about Becky and Petrov, being skeptical or suspecting is a healthy habit. Furthermore, it's a scientist duty. We had horrible experiences in the last few years for not doubting about the propaganda pushed to us in the name of science. The best example is what big pharma sold us as "vaccines" two years ago. Now they are trying to use the same schemes with climate change no less
I love the way Anton delivers his videos. Very straight forward
They both do a great job and repeatedly point out how speculative some of the concepts they explore are. I check for new content on both channels every few days. We are quite fortunate to have such enthusiastic young people to share this fascinating and rapidly evolving subject.
Such a wonderful explanation, thank you.
Keep up the great work, Becks.
So, good times to be alive! Thanks to JWST and Dr. Becky for bringing this new era of discoveries forward to the public!!!
It's great isn't it! We are all slaves who will starve to death unless you slave away everyday, we havea new piece of propaganda to dribble over though, life is fantastic! 😂
I have no doubt in my mind that our "best fit" models for the beginnings of the universe are probably wrong. I love that we live in an age where every new discovery and study pushes us to question everything that we know about the Universe we live in.
The whole idea of science is to determine what we think is real/true until we discover new information. This is the true meaning of a 'theory'. It's also a policy which all good manager's adopt.
Yes previous generations, races and cultures looked up and made up random stories.
Why are you so certain that the best fit models are probably wrong? What are your reasons for why you think thay fail to fit the data?
So glad to live in an age where all we do is find out how wrong we previously were. Lol at “science” when it is always completely wrong after “further studies” are conducted. True big brains
@@messrsandersonco5985unless it’s about evolution, manmade global warming or Covid “vaccines”
Dr. Becky, this is, to a layperson, the most lucid and valuable response to this ongoing debate that I’ve found online. Thank you.
I don't think the universe cares too much as to whether or not we can comprehend the fact of how time doesn't have a beginning or an end or the scope of infinity.
I was waiting for this topic and getting anxious about all the misinformation flowing around. Glad you cleared it. Love your videos. ❤
None of it is cleared yet. Not until you go out and confirm it in person.
@@gonegahgah How are they supposed to do that?
Our smallness, our relative recency, our insignificance in all dimensions just keeps going up.
Humbling, isn't it? Amazing the number of people who can't deal with that.
Thanks B, I’ve been waiting for you to address this! Do you think the next gen telescope will look further and potentially suggest it’s even older?
lol - that will piss them off even more once they are shown to be wrong again. 😂
*I always had thoughts of it being larger than we was able to see!*
Without knowledge of the actual size and shape our eyes may only see where it curves other than the beginning.
Dr Becky rules
☝️
She is just a human, who follows the science of astronomy and communicates that to the public.
@@robertmartin7202yeah. She rules. Synonymous with awesome, she rocks! She’s the greatest! Amazing!
Let me know if you need any help breaking down simple phrases.
@@jennifer7685 That's exactly what I mean!
You talk about her as if she deserves a statue.
I thought she was an astrophysicist, not a geometer.
Always enjoy Dr. Becky's analysis.
I love the bloopers also
Dr. Becky i love your explanations. Easy for me to grasp with my laymans education.
Thanks!
Enjoy your videos, makes me think about the things I don't know anything about.
I love these videos! Very captivating science topics, and of course the bloopers are the best! Adding some blooper humor to all this serious science stuff definitely helps to close each video on a light note. Thank you Dr. Becky for bringing us worthwhile science content in an easy to understand format!
Watched the JWST documentary on Netflix yesterday and wasn't disappointed when I saw you in it reacting to the first images from the project!!!
Would have loved to have had a science teacher like you when I was in school, I would have probably paid more attention in class as you bring such energy and enthusiasm to your videos.... Thank you
Yeah, it was the teachers fault you didn't pat attention in school lol
@@jeremydyar7566 Yes, actually.
@@BrainInJar stop kidding yourself
@@maythesciencebewithyou a good teacher will keep a kids attention. A good teacher knows how to deal with kids.
Be an adult, take ownership of your past mistakes, and move on.
I was a bad student too.
Everyone here viewing this video is a willing participant. Teachers don't get to choose their students.
Becky, Great segment. I second the request for more explanation on delayed/tired light concept. Of course an alternative contribution to redshift is convenient, but unexplained fudge factors are usually not well tolerated. Still, this very problem seems to elevate them. The original A.Ei. conceit that led to his "cosmological constant" lambda was soon re-considered his "greatest mistake". Nevertheless, it has re-emerged, morphed into the "dark energy" unexplained factor needed to account for the slow acceleration of space-time expansion, which is apparent in measurements of progression in the later (closer) universe.
So, is there something/anything known about photons/QED (distilled to the understanding of mortals) that would explain light propagation (dX/dT in a vacuum being an immutable constant, c) in terms that dT can change without also changing XYZ (direction)? Light in a medium slows, as it is absorbed and re-emitted, but also disperses. [Original objection of davini994 nine days ago, and presumably others in the now 2800 comments]. Even if intergalactic space is not a perfect vacuum, does this kind of slowing matter to interpreting the red-shift of absorbance band wavelengths?
Alternatively, is there something UNKnown about light, an unexplained interaction, that would give space (no pun intended) to considering Tired light as a real thing.
What a great time for much of science! Thank you for your content and presentational skills
Thank you for making this video. Ever since this news came out I've been trying to wrap my head around it. You provided info in a way that's digestible to us mere mortals.
Side note: I love your nail colour in this video.
you are thr voice of James Webb in our time, thank you for translating
Your outro at 14:30 is so, so true. Anyone who's tried to imagine being there at a key time in science' history needs to remember, this IS that time.
Thanks for the great explanation of the paper and its weaknesses and of the JWST data it was based on. Your chanell is so much better than others, your way of explanation is so great that you make it understandable without oversimplyfying. It seams natural, but I think there is a lot of hard work behind it. I really apperciate that you explain not only the conclusions but also tha data the conclusions are made of, you show us the graphs and other data visualizations and that you also shares the doubts scientists have about the data and the conclusions. Than enables me to understand the work of astronomers better and astronomy has become a vivid and dynamic science for me.
I am always skeptical when I hear claims of "oldest star found" or "oldest cluster found" because they omit "yet" or "so far." There's also the question of, "What would a star or cluster look like if it was even older?" Might it be that after a star or cluster reaches a certain age that it becomes undetectable (with current technology) from Earth? In other words, does our technology make it IMPOSSIBLE to find anything older?
There is a critical mass of hydrogen, that has to be reached, before the core pressure and energy builds up, to cause the hydrogen to release photons is reached. Hence the period of around 11 million years before any observation of the beginning of stars can be observed. If they don't meet any other matter, they will turn into black dwarf stars. They will emit some light for billions of years before they become a cold black mass. So they can't be observed unless they pass in front of another light source. I would imagine there are millions spread around the inner circle of the Universe.
And yeah, if they can't be seen, how could you date them? But having said that, there are the other stars that have been created since, which does give something to measure. So it's probable there is only a few billion years between them and the millions of cold black masses we can't observe. So the 'oldest' star is a lump of carbon drifting in space.
But i'm a couch potato and not an astrophysicist. So a pinch of salt is all my thoughts are worth.
A while ago I read a book by an astronomer who went to Australia to search for old stars, by which she meant stars whose spectra show a large proportion of helium relative to hydrogen, that being a stand-in metric for age. That's likely the best metric available today.
@@timothyallen6411 Wouldn't iron content be better? Sure big stars reach this stage sooner, but size could be used for the calculation of age.
@@laurendoe168 Great question. My understanding is that the glowing surface of sun-like stars emits light with spectrum mostly from hydrogen and helium while iron would usually be found deep in the core.
@@timothyallen6411 Yes, but wouldn't older stars "leak" some of the light caused by iron? Sure, light created by a star takes millions of years to reach the surface, but it eventually does.
When I heard that galaxies aren't uniform but have a structure, analogous to being on the connections between soap bubbles, it made me wonder if the expansion of the universe occurs at different rates within the bubbles compared to along the lines?
Kind of like walking out into a field and seeing as far as you can. Then , walk to the furthest thing you see, then another picture with things in the next visual distance. Whom will ever know how large our universe is? Or, how long it's been a universe. Just mind blowing.
I predict the JWST will be replaced by larger, stronger telescopes in the future that will look farther back in time and discover fully formed galaxies many times the size of our own. In short, we’ve got no idea of the size of the universe
I really enjoy your videos and the way you explain complex subjects. You have also really inspired my son who couldn’t get qualified answers to his astronomy questions from his teachers at school. We both appreciate your channel and thank you for the time and effort you put into these videos along with making them entertaining. Keep them coming!
Thanks for breaking down Gupta paper for me! I’m surprised that you say that “tired light” is a scattering phenomenon. If that occurred even in the voids (not just in the region close to the source) then space would look foggy - distant sources would become indistinct while the cosmic background would go way up. Scattering causes reddening by deflecting blue photons more than red. Surely Zwicky had something else in mind, like the Sachs-Wolfe effect of photons traveling through deepening potentials.
I like the idea of light experiencing 'friction' as it travels through space. We often say that space is a vacuum but it's clearly not entirely, it's just that the big bits outshine the little bits.
I can totally understand the idea that there's an effect on light as it travels for billions of years.
Tired light has a scary implication:
There may be a distance far enough away that all photons lose their energy entirely before reaching us, meaning there might be a hard limit on how large our observable universe is, no matter how powerful our optics tech gets.
@@WorldbuildyMcNPCfaceThat's exactly the implication of accelerated expansion. Either scenario ends with the limits of the universe being redshifted into absolute darkness.
Greetings from JSC, Dr. Becky! Been hoping you would comment on this one. Love your work, keep it up!
Thanks a bunch for all the explanations, dr. Becky! 😊
What I most liked about this study is the free thinking of the author. He's probably wrong, but we need to do it more!
Anyway, stay safe there with your family! 🖖😊
I love and live on this stuff. The only way we learn is by challenging what we think we know. Like how we still think that everything we have observed is all that there is. Sometimes its not about proving there is more, but simply just not assuming that there isn't, just because we haven't seen it. I think if we are seeing things at greater distances that appear to be older than they should be, then perhaps we need to start thinking about "our" big bang as perhaps being 1, in a sequence of many. The last in a line of a few. It would only make the space that the content is expanding into much older, but It would also explain why we are encountering things, with signs of being older than this current expansion of content. This may also be why there might be things beyond the threshold of our local expansion, that are only just creeping into our view because of JWST? The simplest version of what i'm thinking would be that is the fabric of space we are expanding into if infinite, may house other big bang clusters of content. Our "universe" is local to us, @ 13.9bn years old, but there might be other big bang clusters spread through this fabric in the same way we obvserve galaxies. In reality It's just another layer, but it seems to fit the pattern of stars solar systems galaxies clusters, super clusters, big bang clusters? Just my thoughts. sorry.
Respectfully, and in my humble opinion as a scientist, it is a very brave scientist who places more weight (reliability) that the difference in the 'traditional age' vs the 'new suggested age' could possibly be explained by error in Gupta et al's calculating the Red Shift, given we know essentially NOTHING about what makes up 95% of the composition of our Universe! In my opinion Gupta et al's paper is much closer to the "observable thruth" which also dispels the "notion for the Big Band" circa 13.8 billion years ago! [In my 50+ years studying applied chemistry, geology, celestial mechanics, I have always believed "the big bang" was ficticious due simply to the fact of not knowing what 95% of the universe constitutes]. A very good video, nevertheless. Cheers from Down Under
I think this will always be a problem till we truly understand how time actually works and interacts within our universe.
Considering that time is the most accurately measured physical parameter in physics, I think we have a very good understanding of how it works in our universe.
@@stargazer7644Our measurement of time is a construct relative to our own solar system.
People calling things like our understanding of timespace a "very good" understanding of things is why this very video has been made.
It's foolish to believe we have even a slight clue of such phenomenon in the vastness of the universe.
@@johnnymo4000Your measurement of time is only relative to YOU. Time for me flows at a different rate than time does for you. It has nothing to do with where the solar system is.
Thanks Dr! I've been avoiding a bunch of click-bait-title videos on this waiting for you to lay out the claims in the paper. Well explained!
this is literally a clickbait title
Way back in recent history, the only media outlet for astronomy was, as he was then, Mr Patrick Moore's The Sky at Night; on one episode, he introduced the idea of HALTON ARP's about quasars, red shift and other controversys. I bought the book from America, somewhat of a feat back then. He had some theory that reminded me of your current post. Lol Pete on the IOW
The more time that passes, the more we learn how wrong we currently are. But that’s science. There was a time when we thought an atom was the smallest particle in existence.
Thank you for the great work, this is why we, the viewers, love Dr Becky
definitely brighter, at very least.
I love seeing headlines and being like "that's not correct anyways probably" and then having Dr. Becky explain why that's the case
Credit to you for engaging an audience of 600k views with such a sprawling subject. I very much enjoyed it, too, as an amateur (and academically challenged) Astro physics enthusiast!
The view count is nearly her subscriber count. No fake subs! 👍
Imagine how it must feel to work in a field where you have no confidence that the fundamental basis of the field is correct, and the latest theories don’t bring any additional confidence?
Oh boy, this is the first time I'm this early! Hi dr Smethurst, I really appreciate all you're doing
Data from JWST has been such a massive leap in our understanding of the cosmos, and we've barely scratched the surface. What a time to be alive. The absolutely gorgeous pictures are a very nice bonus.
I've been very worried for many years about humanity's waning interest in space exploration, space agencies losing funding, and more "local" issues drawing attention away. I hope that JWST and the upcoming Carl Sagan Observatory continue to get more people looking up.
Astronomy has always been more a luxury item than an essential one, at least when it comes to the distant universe. I still believe it should be well funded, for several reasons but we do have more pressing issues to deal with than understanding the age of the universe, so if money is tight...
@@EnglishMikeI couldn’t disagree more!
@@EnglishMikeAstronomy is most definitely not a luxury. Many scientific discoveries were made thanks to space exploration that have transformed our day to day lives. Without astronomy, there is no space exploration. And space exploration gave us important technologies 😊
@@Power_to_the_people567 Space exploration and astronomy are two different things. I certainly agree that much that we have learned through building telescopes and launching them into space, as well as designs of other spacecraft has been beneficial in other walks of life, but as of right now, if -- say -- we had to sacrifice 90% of the world astronomy budget in order to halt or even reverse climate change, then everyone (except those whose livelihoods would be sacrificed) would agree it was worth doing.
JWST is a phenomenon, and I'm very happy it's up there doing great work, but other than satisfying our curiosity, there's not a lot of practical use for it when it comes to improving life here on Earth. It's a luxury because we have the time and money to spare to do these things. It hasn't always been the case.
I love the way they put .8 to sound detailed & then just double it & add .7 to sound detailed, again!
I think what we're learning is that our physics is based on too many assumptions and some of them are probably wrong. What we have works only slightly better than guessing after a certain point.
Thanks for going over this paper. I read it when it was released and thought to myself, “what would Dr Becky think?” So I sent it your way. I wouldn’t doubt you had read it by then. 😊
Loved this video! Was waiting for it ever since I heard about the paper. Dr.Becky just does an excellent job at explaining the nuances what a dope space channel!
Is inflation theory still a thing? I watched your episode on the gravitational wave background and really enjoyed it. If I’m understanding correctly, the gravitational wave background was emitted prior to the inflationary epoch, right? Does that mean that there’s the potential to build up an accurate model of that event? And would that effect the apparent age of the universe?
For redshifted light, how do you know what type of 'light' it started out as? And along the same thinking, do we know the speed of shift going through the spectrum? What I'm getting at is if we are seeing any redshifted light, do we know if it started as gamma radiation say or UV? Because wouldn't that make a difference in the time traveled/distance?
Stars are Composed of A fairly Limited set Of elements That are Emitting the Light. (up To iron)
each Of those Elements has A unique Set of Light wavelengths Which match Said elements.
Experimentally, we Can independently Find said Wave lengths Of light For these Materials.
However, when Using this Technique For other Stars, all The light We get Is usually Much more "Longer" than Expected, but If you Just "moved" The spectrum For the Lines to Match up, It matches Nearly perfectly.
Thus, red Shift.
(Not an Astrophysicist, but This is My understanding From what I remember From a Couple of Lectures in School, and This is Fairly simplified. )
That's how They know How much It shifted.
They figured Out that The shift Was proportional To the Distance travelled, And i Think it Was timed Via pulsars, Which we Figured out The distance To by Using the Orbit of The earth As a Telescope with The effective Size of The orbit Of earth, To measure The parallax, Which informs Us of The distance To those, And thus The calibrations For our Instruments.
However, there Is the Chance other Things do Get in The way Of that, Which would Affect the Rate of Redshift, and Thus the Distance travelled.
If, say, The rate Of redshift Isn't actually Constant, that Would throw Everything off. Same total Shift, but Probably unable To tell How long It took.
This really touches on a subject I'm really interested in--our ideas of the differences between stellar evolution in population II and population III stars (and their varying metalicity) and how this affects star formation and creation rates. I'm thinking if we had more data on this, our model for the spread of types of stars we assume in these most distant, older galaxies would change. I need to read this paper for sure.
_"I need to read this paper for sure."_
Don't bother. It is nonsense. And the most distant galaxies we see re low mass and low metallicity. As expected.
A photon experience stretching instantaneously because the time stops for a photon?
Epochs of science and understanding are amazing. I was an astrophysics major (amongst many others in my 18 years at university) before becoming a geography major, a science I refer to affectionately as "the science of how man relates to the universe." This is the sort of stuff that gets me really quivering; the epochs of our understanding. I read this research before you made your first video regarding it and felt the same as you: Skeptical. But that's just good science. I still don't buy it as fact, but it could open a door to us realizing that the universe is actually 18 billion years old. Let's see where the research takes us. 🍻 Cheers, Dr. Smethurst.
Since the universe had more concentrated mass in the beginning could some of the red shift be due to light trying to escape mass (tired light) as well as the red shift caused by the expanding universe?
Great video, new subscriber here. I like it a lot when scepticism is used. There are sooo many channels out there that gulps any theories that pops up and take it as Gospel, maybe because they want to believe and/or maybe to use caps to lure viewers to watch a "REVOLUTIONARY DISCOVERY ".
True science is to never stop asking why, how, and butwhatif 😊
Scepticism is especially important since even the authors of these kind of papers might not belief such alternative models are actually correct.
Thanks for another great video. If time were passing more slowly when the universe was smaller and more dense, would this affect our estimate of its age?
Thanks for breaking it all down. You & DollarStoreThor (Kyle Hill) are some of the best science educators on YT.
Back in the nineties, before the accelerating expansion was discovered, we had the enigma that the oldest stars were measured to be older than the age of the universe. This new conflict in measurements feels to me a bit like Groundhog Day....
Hi Dr. Becky, Has the possibility of non-straight line travel of light been accounted for? To me that would seem more likely than interactions red shifting the light itself, especially if fractal principles apply.
I suppose the next step for Gupta et al and anyone else that wants to explore it is to find some evidence that the new parameters work as expected, yeah?
(where the age of the observable universe was calculated from a constant expansion rate the observable universe acclerates - the age is probably much older than we think )
Hey! I don't know much about all of this, but I'm curious, could there be some way that maybe earlier galaxies would come together quicker in the early universe and then they slow down ad the universe expands?
Weird thought but what if dark matter/dark energy, or whatever is making up the remaining ~90% of the universe that's seemingly "keeping things together" is what our universe is expanding into. Like an "explosion" of viscous space (and time ig) expanding inside of a fluid (dark matter or the primordial ooze)
They think the matter has an attractive force while the energy is repulsive, yes?
Wow! I thought of the "tired light" idea several years ago on my own. I think it's going to turn out to be the rebuttal of the dark energy idea.
Thank you for give us the level goods. It's really unfortunate that news media always latch onto sensationalist stories and report them immediately as scientific consensus. It really skews terribly how the public understands how science works.
Even if it was, I couldn't read any of these papers in all that time.
Thanks for breaking down this info for us Dr
I don’t know but I am looking forward to a nice cup of tea at the end of the talk.
This hybrid model also eliminates the need for dark energy, doesn't it? Does that give another way to calculate the ratio between expansion and tiredness, as in, "what percentage of the red shift has to come from tired light to eliminate the supposed acceleration and thus dark energy?" Awesome vid by the way!
I suspect tired light theory and the expansion of the universe weren't mutually exclusive of one another in the first place. This seems to happen quite often in physics; you get several competing models framed in the popular press as 'competing' with one another when they either complement one another, or otherwise don't mutually exclude. It makes perfect sense that, for objects moving away from us, their light becomes progressively more likely to interact with dust and other material in the intervening space. In the same way that you get a Doppler shift with sound waves travelling through a progressively larger number of air molecules (as in a train moving away from an observer), the light would be likely to lose energy with an increase in distance.
Nice but how do you explain the time dilation and subsequent slowing down of spiral arms in the early universe which fit with expansion speed
Two questions that my grandkids came up with after watching your video from a while ago and I simply was stumped. 1) If there is another Univers out there, could we collide some day? 2) If the big happened once, could it happen again now? Would that destroy this universe and make a new one? If someone could give me an answer that I can make sense of to them that would be great.
Another factor that I have been thinking of is gravitational density impact since it's known that we have gravitational lensing and the notion that gravity slows down time.
The early universe had a higher mass density since it was smaller, so could that impact the perceived age and actual age of the universe?
Thanks Dr Becky. Throwing in a wild idea here: is it possible that the mass of the universe itself comes into play at those distances (z=11 or greater) and that causes the horizon of the universe to 'sag' a little bit and that distorts our view of how old the universe is? It's like collective mass of the universe itself curves spacetime ever so slightly away from any observer.
As things get older they do tend to sag.
@@ChristopherFynn001 I knew that !
I wondered if the mass-density of the universe would be a factor. The universe is smaller, the mass is more compacted, gravity is locally more influential, more stuff just comes together faster?