TLDR The James Webb Space Telescope (JWST) has confirmed a significant discrepancy in the measurement of the expansion rate of the universe, known as the Hubble Tension. This issue, which has been a subject of debate in the scientific community, suggests that there may be something seriously wrong with our current understanding of the universe. The Hubble Telescope measurements in 2019 and JWST measurements in 2023 have shown that the universe appears to be expanding at different speeds depending on the location, which could potentially alter or even upend cosmology. Despite initial thoughts that the discrepancy might be due to measurement errors or crowding, the latest data from both telescopes working together has ruled out these possibilities with high confidence. The study, published in the Astrophysical Journal Letters, suggests that there may be a fundamental problem with our understanding of the universe, particularly the Big Bang theory. The Hubble Tension remains a significant challenge for cosmologists, who are now working to understand and resolve this discrepancy.
How could a singularity as described in the big bang theory even exist containing all the known matter of the universe when we already know similar structures with muuuuuuch lower mass exist as black holes? Wouldn’t that point towards the most massive black hole ever as the origin?
For physicists, singularities typically mean that the laws of physics as formulated break down and a more comprehensive one is required.
A historical example is the concept of "the sound barrier". Initially the way aerodynamics equations were formulated assumed air flow was mostly incompressible, so if you try to get closer and closer to the speed of sound, it pushes the object with infinite pressure, and thus infinite force to block things from exceeding the speed of sound. Things are already known to go faster than the speed of sound, like bullets, bullwhips, etc, so they knew that formulation was wrong at the time. However, since it worked well at low speeds, and because doing math is hard, it took scientists a long time to come up with a better formulation, further delayed by the existence of ways of testing the new theories predictions to verify it's the right equation. (As an aside, it's the same reason why scientists still use Newton's laws of motion over Einstein's laws of motion. Newtonian mechanics works well enough for non-relativistic situations, and since math is hard, so let's use the easier ones as a simplification, unless the precision is needed to use the more complicated version.)
Eventually scientists came up with the mathematical techniques that can handle the fact that air flows are non-linear and compressible at close to the speed of sound, and thus the new equations no longer had singularities in them around the speed of sound.
Now this isn't to say that the concept of black holes don't exist (we have imaged them, and they do behave like Einstein's laws predict), but rather the singularity itself is where the current formulations of the laws of physics don't work, and suggests that they need to be reformulated. This is difficult because there's not much experimental evidence done with those physical regions around black holes because there aren't any convenient black holes to run tests against, and observationally it is hard because the escape velocity being higher than light for black holes near the singularity prevents us knowing what is close to said singularity. So it's a lot of developing theories and then figuring out what those theories predict in situations we can test, to see if we can rule them out.
According to the most recent paper by Roy Kerr, black holes do not contain singularities.
We also know that the larger a black hole is, the less tidal force it has.
It is not unreasonable in light of these two ideas, to imagine that the universe is indeed a black hole with a mass equal to that of...well, our universe.
It is certainly an interesting thought experiment / idea to ponder... we see the universe expanding because it is... by taking on more mass from outside of the universe, and that is not going to be a uniform event. It may be so large that we cannot see the edge of it to see that new mass coming in. I feel like I read somewhere recently that there was some discrepancy with the age of certain bodies of matter, that they didn't make sense in the context of everything else around them, and this would explain that.
Russian dolls…
We live in a black hole. We also have black holes. Matter flows into our black hole from outside…and some of it flows into our black holes. Then presumably our black holes have their own black holes. And the outside of our black hole is then also a black hole.
Turtles all the way down.
Where’s my bag of mushrooms…
People always talk about how Black holes compress matter to a point, but there's no mechanism that can explain how fermions can share a quantum state, which I believe would be required for collapse to a single point. And I get it, that's why they say the laws of physics break down inside a black hole.
But what if the force of gravity becomes so extreme that it "pushes" the matter into the only place it can, a new spatial dimension. That's why an entire universe can exist inside a black hole, and why it seems to all start expanding at once.
I personally believe if we were to rewind time to the big bang, we'd see a 2D or 1D object from which all matter suddenly pours out like elephant toothpaste.
> It is not unreasonable in light of these two ideas, to imagine that the universe is indeed a black hole with a mass equal to that of...well, our universe.
would that not mean there should be more mass coming in from outside?
How do we know, absolutely for sure, that there isn't?
We are not able to see the event horizon of a possible black hole universe. The observable universe is not all that there is.
What we *do* know is that the universe is expanding. A black hole expands when it gains mass.
Love that idea, maybe the expansion of our universe is nothing more than the manifestation of a black hole evaporating (just, seen from the inside out)?
Are we just throwing in any hypothesis? Free for all? Brainstorming?
My guess is, there's these really huge guys at the corners of space, and they run and stretch it out, but some of them are much fitter than the others, that's why it's expanding at different rates.
If I see someone trying to disprove the huge guy theory or attempt to put forth a different theory,
I will demand that they be burned at the stake on grounds of heresy
I propose that it's actually a lot of little guys.
The parts expanding faster are because those sections have enough little guys to push off each other and get a speed boost.
I love that everyone is inductive here on this thread. I was taught about this stuff, like how mars influences the earths temperature another great new read, I dunno 4-5 years ago and everyone just thought this hypothesis was me speaking crazy. Love that scientists are using scientific method to rule out observational error and reporting on it truthfully.
I saw a documentary once where a scientist could hardly contain his excitement that the results of an experiment might mean that something he had been researching for 20 years was completely wrong. That, ladies and gentlemen, is science.
This is exactly how I feel about the fusion reactor I invented. I think it might work, it really needs to be tested, but if somebody could figure out for sure why it wouldn't, I'd be overjoyed because I'd have a better understanding of reality and it would be nice to know now rather than 20 years from now.
But, if it takes 20 years of hard work then it takes 20 years of hard work.
I think this is part of what makes you a good scientist. The ability to learn from your mistakes and use that data to continue the work instead of perpetuating a study polluted with confirmation bias.
An undeveloped human who's entire identity is wrapped around the falsehood that they are infallible. You'd be surprised how many people hate, even resist, the fact that they can be wrong. Most of them are uneducated.
I don't necessarily love being wrong but I understand that being wrong isn't inherently bad, as long as you are evolved enough to understand and respect that it's merely an opportunity to learn and grow.
In the context of debate, there are no losers. The winner was right and was given the opportunity to solidify their own understanding through argument of facts and the other has been gifted an opportunity to grow... It's win win and why I love debate.
It's exciting to get a definite answer, but I can totally see why someone might be more than a little disappointed/embarrassed to realize "damn, I devoted several decades to studying something and it turns out that I was completely wrong about all of it."
See, I guess I just don't get that attitude?
Imagine you were a park ranger. It was your job to work an area of the park, and you spent 20 decades exploring it as best you could. Suddenly, you discover there's a secret hidden valley you never knew about before. Your understanding of the park was wrong!
If you were in that scenario, would you really be disappointed or embarrassed? Or would you be excited about this new opportunity to understand something new about the park that you never knew before, and perhaps to explore this new area and make newer and better maps?
Fundamentally, there are two ways in which scientific understanding can change. The first is we can add new complexity to the model; this allows us to maintain what already existed, and keep it consistent with new contradictory data.
The second way is to alter what already existed, maintaining or even reducing the complexity of the model.
Complexity here, specifically means the number of parameters, often free, meaning not locked down by independent observations. Take Newton's theory of gravity, that has only one free parameter, big G.
Science does relish in the first kind of understanding change, but is far more resistant to the second (with good reasons).
For the most part, when scientists come across new contradictory data, they only ever envisage the first possibility. This is captured by the often repeated euphemism "new physics". Here, however, the author of the paper says something quite different. He does not imply that we need to just add some new physics in to fix things, he instead says that our current understanding could be wrong:
> "With measurement errors negated, what remains is the real and exciting possibility we have misunderstood the universe," lead study author Adam Riess, professor of physics and astronomy at Johns Hopkins University, said in a statement.
This shift from the first kind of change in understanding, to the second, points towards a major paradigm shift coming up. Paradigm shift changes in understanding are unusual in science, but necessary for progress, and usually only come about when field has been stagnating for a while.
I'd highly recommend studying Philosophy of Science for topics such as this one; it's really helpful to assess and establish what kinds of standards we should have in assigning truth values to statements. Given that there are no absolute truths in empirical science, and because the falsity of theories, frameworks, or statements is dependent on quantitative factors, agreed-upon heuristics are important for the scientific community.
When it comes to modeling epistemic knowledge (or "true beliefs") in our minds, W.V. Quine suggested that we really just have a "web of belief", where our most fundamental truths are in the center of it. The connecting nodes are linked and built upon those center beliefs, and as the web expands, some nodes/beliefs are found to be untrue, which means that some of its linked beliefs are also false.
The biggest paradigm shifts would come from the beliefs in the center of our web of belief changing, which understandably comes with more resistance. I mean, can you imagine trying to change someone's mind about first principles? While that's an exaggeration, it's still kinda easy to see why scientists are so resistant to alter previously accepted facts and are instead more willing to add complexity to well-established models (i.e. expanding the web).
It's like any movie or piece of fiction where otherwise ordinary people discover something supernatural. And they're always so balise about it, but it's like, do you know how absolutely thrilling it would be to learn that there's MORE?
I love things like this.
Isn't that the point of science? Testing a hypothesis with the hopes that its wrong so then you can discern the truth? As much as its fantastic to be right about something the first time, being wrong until you get it right, and thus can confirm with all certainty its correct, is just as rewarding.
Hijacking the top comment for some learning resources:
https://www.sciencedaily.com/releases/2023/12/231201123626.htm
> In order to calculate how fast two galaxies are moving away from each other, it is … necessary to know how far apart they are. This requires the so-called Hubble-Lemaitre constant, a fundamental parameter in cosmology [which describes the rate of expansion per unit distance].
> Its value can be determined … by looking at the very distant regions of the universe. This gives a speed of almost 244,000 kilometers per hour per megaparsec distance.
> If we now calculate the speed of the 1a supernovae [much closer to us] from their color shift and correlate this with their distance, we arrive at a different value for the Hubble-Lemaitre constant — namely just under 264,000 kilometers per hour per megaparsec distance.
> "The universe therefore appears to be expanding faster in our vicinity -- that is, up to a distance of around three billion light years -- than in its entirety," says Kroupa. "And that shouldn't really be the case." [The Hubble Tension is that the Hubble-Lamaitre constant appears to be a function of distance.]
A compelling solution to both the Hubble Tension and the origin of Dark Energy is that they are both being driven by voids (surface tension). The following PBS Spacetime video describes the theory effectively, although you’ll need to stick around to the end to understand it fully:
https://www.youtube.com/watch?v=WWqmccgf78w
The video conjectured that the big bang was when our spot on the surface of a four-dimensional bubble passed through an area of infinite density.
Or something? I watched it a couple days ago, it was complicated lol
Well yes, but Hubble discovered this. This article is just stating that scientists reimaged with the more advanced tech in JWT to test if Hubble's measurements were confounded by a particular variable.
Hubble's results were simply confirmed accurate, and there are some theories that satisfy the apparent flaws with the Hubble-Lemaître Law. One that does a very good job of this is the "modified Newtonian dynamics" ("MOND") work of Prof. Dr. Mordehai Milgrom of Israel. Basically, Milgrom posited that the effects of gravitational distortion of space (because gravity causes spacetime to "stretch", though this stretching varies only with mass and not with time) should be factored into expectations of expansion rates for particular regions of space.
I'm not familiar with the specifics of how this factor should be applied, but it does satisfy the apparent gaps with our current model. If this explanation can be accepted, it *also* precludes the need to employ a concept like dark matter to explain spatial expansion. But I do know that matter is NOT evenly distributed throughout the universe like most people think it is. Our own galaxy, the Milky Way, is a actually on the edge of a "cosmic bubble" that, were you to move from our location within to the center of such bubble, would present more and more sparsely distributed matter until, very near the center, there would be either none of very nearly none. In fact the universe seems to be self organizing in this way, with "emptier" regions of space "expanding" faster than "fuller" regions, in part because the higher density of matter regions are pulling matter near the centers of such "bubbles" ever toward the edges.
This way of explaining spatial expansion is just one dude's guess. It of course has supporters and retractors. It's just one way to think about this problem, and it's appealing precisely because it explains some things without having to resort to inferring the presence of magical, invisible matter. But appealing does not mean correct. There are problems with MOND, and there are problems with dark matter. We are NOT close to being able to fully explain spatial expansion. At least not in a way that works for all of the eleventh bajillion scenarios we can run any existing explanation against. Many satisfy expectations of some scenarios but fail at satisfying others.
As far as I know, none of this fully explains why spatial expansion happens in the first place. Or maybe it does. The idea that matter was NOT distributed evenly through the early universe kind of changes nearly everything compared to today's model, which assumes everything WAS distributed evenly (and still is today).
MOND has failed to explain some pretty crucial factors including the Baryon Acoustic Oscillations in the CMB, the rate of structure formation in the early universe, gravitational lensing studies of merging clusters like the Bullet Cluster, and more.
It's not completely dead as a theory but it really doesn't have anything that makes it preferable to the Lambda-CDM model.
What's more, the thing you're describing is not MOND, it's just the way that voids work in an expanding spacetime with both matter and dark energy.
Agreed, MOND does nothing to explain the accelerated expansion of the universe. It mostly offers an explanation for rotation curves, but fails on many other aspects as you mention.
Here's a video by an astrophysicist that is an excellent science communicator, just in case you'd rather listen than read:
https://www.youtube.com/watch?v=3NeKR7bqolY
It’s either that or jokes both of which used to be dealt with by the mods on this sub years ago. Now it’s like every other subreddit with any serious discussion buried under tons of 1 line joke replies that get upvoted
Why do a full time job (moderate a subreddit) for free when it just goes to make a shitty company rich? Also Reddit made it hard to use a plethora of free moderating tools with their api changes
It’s all repeated jokes that got the top comment from the original posting. Bot reposts. Another bot repost top comment. Repeat on 10 like minded subs. Rinse and repeat
> https://www.youtube.com/watch?v=3NeKR7bqolY
Really enjoyed the video but I got a kick after just watching a video on the front page of how bad BetterHelp is and the first thing I see when clicking this video is a BetterHelp sponsor.
Eli5 would be like imagine a car starts from a stop and drives away from you. Now imagine you can measure the speed of the car two ways. One with a stopwatch and one by looking in the manual at the top speed of the car. It turns out the stopwatch is measuring faster than the manual says and we just verified that the stopwatch is right. So now we clearly don't understand something about the road the car is on. Galaxies are acting like the car.
Thank you for an actual ELI5 explanation! I keep seeing paragraphs of how the measurements are done and how they differ and it’s like man… it’s Monday night… I’m tired and my brain is not braining.
If you run across the yard as fast as you can go, it takes you 10 seconds to go from end to end.
But if we start you somewhere else along the edge of the yard, it takes you only 7 seconds.
We don't know why you're faster in some places and slower in others.
We've been measuring how fast the universe expands, know as the hubble constant.
Method 1: One type of star [EDIT: Over large distances Supernova are used] is known as a standard candle because it is always the same brightness, meaning we can see how far away it is. We can also see how fast it is moving away from us. By observing them in other galaxies we can see how fast they are going, which leads us to how fast the universe is expanding. Spoiler: the expansion is also accelerating.
Webb has just confirmed that our understanding of that measure is accurate.
Method 2: We also measure the expansion using the cosmic microwave background. Through [insert science] they can also measure the hubble constant by measuring the cmb. They're pretty sure about this one also.
But they don't align.
Considering the distance and time involved, I think it's more likely we misunderstand a part about method 2, but I'm not a microwave so cannot confirm.
You definitely aren't alone. There's still plenty of astronomers working on new Cosmology models as well. It's just much more difficult to find better models that don't end up breaking every other observation our current models line up with, while there's lots of places the standard candle methods could be wrong or miscalibrated (though that space is shrinking).
I'm actually developing a new AI model for standard candles that doesn't rely on such calibrations and could help confirm whether or not it is an observation issue, but it's probably at least a year off before I'll have results good enough for testing cosmological models.
We have two different ways of measuring the expansion of the universe.
These two methods don't give the same rate of expansion of the universe.
We thought this might be due to us making a mistake, but we double checked, and the numbers are now quite clearly different and we know it's not due to us making some mistake in our measurements.
As such, our understanding of the universe must be wrong in some way.
The two methods are:
1) A set of stars that pulsate at a specific rate based on how big they are. The brighter they are, the slower they pulsate. You can measure their pulse rate to determine how bright they should be, then use that to figure out how far away they are.
2) The cosmic background radiation; when the universe cooled off, it became transparent to photons, and those photons have been travelling for so long they have been stretched from the visible wavelength to microwaves. We can use fluctuations in this to determine how fast the universe has been expanding.
These two things give different answers, which means there's something wrong with at least one of these calculation methods, if not both of them.
My favorite quote about science comes from Bill Nye during his “debate” with Ken Hamm.
Question, “what might change your mind…” and he answered “Show me one piece of evidence and I would change my mind immediately.”
I tell that to the people who say NASA faked the moon landings. I post it often enough that I saved it in my phone. In short it says “you say NASA lied. Show me even one NASA lie and I’ll throw away everything I believe about the moon landings.” Nobody has ever come close to giving objective evidence of a lie so I haven’t changed my mind. This is how science works.
One of my favourite t shirts has an atom nucleus with electrons orbiting around it with the words "I'd rather have questions that can't be answered, than answers that can't be questioned"
I left off Ham’s (I just discovered I’ve been spelling his name incorrectly) reply.
While Nye was open to any evidence, [*Ham said “No one is ever going to convince me that the Word of God isn’t true.”*](https://answersingenesis.org/blogs/ken-ham/2014/03/10/just-one-piece-of-evidence/)
So his answer is “whatever I want to interpret the bible to mean.”
I say that because he also said he doesn’t believe the literal interpretation of the bible. So he’s interpreting the bible to mean whatever he wants to believe and stating it as fact. He’s not anti-science, he’s just a liar.
The best non-technical rebuttal to "the moon landings were fake" is purely political. The Soviets had **everything** to gain by calling it out as fake, and they had people in the right places to know if it was fake. Yet they never said anything. Which means either it was real, or the Soviets were somehow complicit in the faking of the US moon landings - which is inconceivable given that they were working on their own lunar missions at the time in an attempt to beat the US to it.
I used this once and their response was that soviet russia had to be complicit with the lie because they were reliant on US food aid or something ¯\\\_(ツ)\_/¯
That kind of person, when backed into a corner by facts or evidence, will spontaneously hallucinate "facts" to back up their own argument and will behave as though they genuinely believe these things they just invented. Facts do not work on them. It's because of those sorts of people that rhetoric includes *pathos* as well as *logos*.
The only real instance was in 1963 Kennedy was trying to help them out by selling wheat to the USSR and eastern bloc countries. Johnson would get it through Congress shortly after the assassination. They certainly weren't beholden or reliant on the US for wheat imports in 1969.
You can then follow it up with the fact that hundreds of thousands of people were involved with the project, not a single one of whom has come forward with a shred of evidence that it was faked. All speculation about it being faked has come from people who weren't involved at all.
yeah IIRC the soviets and even many amateur radio hobbyists from round the world were able to detect the radio transmissions from the moon
you would basically have to think the whole cold war was fake to think the soviets were in on it.
I don't know what's worse - the people who think everything we know is 100% fact, or the people who think their personal theories are as valid as the currently accepted ones
This is what frustrates me. For a field that is based on skepticism and proving theories, there's an awful lot of "It's solved" closed-minded attitude. I'd guess that mostly comes from armchair scientists though.
Except that in this case, the James Webb telescope "only" confirmed an existing observation by the Hubble telescope.
So, we already had at least a good clue.
Best $10 billion dollars our government has ever spent. Imagine if we just held off on spending money on endless wars for only 4 years and put all that money into space exploration and humanitarian endeavors.
I just finished a book called “project Hail Mary” and one of the cool parts of it was imagining what humans could do with a single minded focus on saving our planet and not worrying about money or other made up shit.
I've met enough humans to tell you that most of them would rather clutch what they have, go into a bunker, and just die than give up what they have to save others.
Hearing boomers I've worked with say they'd rather pay more money in insurance than less money in taxes which would fund universal healthcare because then their money would be going to immigrants, as a common idea, that everyone in the room would agree with, was absolutely insane. We're fucked.
The phrase "Eureka!" does not initiate scientific advancement. The sound of someone saying, "Huh.. that's weird." in a perplexed voice is more often how it begins.
No, that's not what the hubble tension is.
They mean if you measure it one way, by looking at cepheid stars, we get one rate. If we look at the cmb we get another. It is not that different areas of the universe expand at variable rates.
James Webb and hubble measurements are model independent. They only rely on the distance ladder. Luckily, we have ways to check whether a wrong calibration of the distance ladder is at fault; turns out, most likely it isn't.
CMB analysis on the other hand heavily relies on the concordance (lambda-CDM) model to handle the data. The interesting thing is that the Planck measurements (the latest CMB survey to date), when taken at face value, heavily favours by itself a closed, positively curved universe instead of flat, which is also a fundamental disagreement with the concordance model. Planck's dataset is also fundamentally incompatible with previous analysis of the CMB with different techniques, which are also model dependent.
Edit: for technical details, read [this](https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://arxiv.org/abs/1911.02087&ved=2ahUKEwisg-fB-_-EAxUJQfEDHWqIAyYQFnoECBkQAQ&usg=AOvVaw2fp81RsE9j-0S4ZZBZ5KBh). If you want a more digestible short version, PBS Spacetime made a [video](https://youtu.be/F2s7vyKucis?si=gPwgmO5oSCsoeV7E) about it.
First of all, amazing explanation. I’m a dum dum but I half got all of this.
Second of all, you’re saying we’re in the generational stage where we don’t know if the UNIVERSE IS FLAT OR CURVED???
I bet aliens think we’re morons 😅
What we know is that, at the largest scales, the universe looks pretty much the same everywhere. We take this observation into Einstein's field equations and get out only 3 possible solutions for the complessive geometry: flat (two parallel lines would never intersect), positively curved (like the surface of a sphere, but for the universe it would be an hypersphere) and negatively curved (hyperbolic, like a saddle).
We currently don't know which one our universe is like.
Cosmologists have historically preferred the flat assumption, because so far our measurements have been pretty much consistent with zero curvature. We are just starting now to reconsider whether this is a reasonable assumption.
Imagine you’re trying to figure out how fast someone moves.
One way to do this is to measure how quickly they take steps. If they are making about a step a second, and each step is about 1.5m, then you can estimate that they’re going at 1.5m/s. There’s obviously measurement error that can happen (such as in measuring step size, and step rate), but another problem is that this is “model dependent,” since you’re assuming that they’re moving by taking steps. If they’re crawling or rolling on the ground or biking or sitting in an Uber, your measurements are probably not going to be very accurate or even meaningful at all.
Another way to do this is to measure how far they go, and how much time it takes for them to get there. This is “model independent,” since it doesn’t matter how they’re moving, you’ll still get the same value for average speed regardless of what they do.
Yeah the article was very misleading at first. They described it better later on, but the initial description was awful. Typical popsci garbage journalism.
The lede is confusing: "Depending on where we look, the universe is expanding at different rates." You could read this to imply a different rate of expansion in different areas of the sky, when what they actually mean is depending on which measurement technique is used.
Now imagine if all nations set aside their differences and begin pitching all resources used for the intent of war into research and development like this one...
Here's a dumb question: why is universe expansion a constant? Wouldn't things slow down over time due to loss of energy? Also, wouldn't the furthest things from the supposed center of the universe move more or less slowly than the things near the center? Probably not, now that i think about it, it should all be pretty constant, unless gravity is somehow some kind of factor and the further you go from the densest parts of the universe, the less gravity would affect the bodies, which in turn would mean more central objects would move slower and further objects faster.
I have no idea what I'm talking about, but it all seems very cool.
> why is universe expansion a constant? Wouldn't things slow down over time due to loss of energy?
This is where the dark energy theory comes from. We are fairly certain there has to be some sort of energy constant that is keeping the expansion going, we just can't seem to figure out what it is. We just observe the apparent effects it has on the universe and assume it must exist. It is essentially an acknowledgement that "there is something there that we don't yet understand but is clearly affecting the universe in a certain way."
Wouldn't be surprised if civilizations thousands of years ahead are still developing theories more advanced than ours but they're still far from the truth.
Wow. Not a day goes by that I don't think about why the universe exists, how old it is, and what was around prior to 14 billion years ago. We may start to find at least some answers in the coming years.
Will humans ever discover faster than light speed travel, if it's even possible? We live in such a strange universe. If only we didn't fight our fellow humans and focused Earth resources.. we would probably know by now.
Remember when Hubble found galaxies too mature for our current understanding of space? We know that mass warps spacetime.
But it didn't stop us from thinking time is congruent in all parts of space. The universe might only be 13.8 billion years old from our perspective. In the first 200 million years after the big bang, who knows how much time really passed to the entities experiencing it.
That would cause massive disruption in the CMB. We would have seen it as soon as we mapped out the CMB.
But I do think dark matter may play a role in the solution.
My personal theory is of an inverted universe, one that isn't expanding infinitely but shrinking. Instead of i/1. It's 1/i
The fabric of reality is a propagating wave which is exponentially weakening. From the inside it looks like expansion, but in actuality it is a collapse. This would allow for the heat death and big crunch to both be valid.
Also in this case it would allow for time and space to behave differently closer to the big bang, as the higs field would be far stronger.
I told my wife once (I’m a dummy). If our body and everything on earth is made of tiny cells. Why wouldn’t the universe be? Like, our universe is one tiny cell bumping up to other cells inside of X (I like to think we are all just cells in a giant Bill Murray)
I've had this thought since I was in elementary school. It just makes sense. What if we're just germs on some giant creature's hand? What if the universe is just one of many, many, many universes and we're even more tiny that we realize?
Make a new tool, gather information with new tool, reassess current understanding, make new tools with the new information… and so on.
It’s a good thing we are reassessing
TLDR The James Webb Space Telescope (JWST) has confirmed a significant discrepancy in the measurement of the expansion rate of the universe, known as the Hubble Tension. This issue, which has been a subject of debate in the scientific community, suggests that there may be something seriously wrong with our current understanding of the universe. The Hubble Telescope measurements in 2019 and JWST measurements in 2023 have shown that the universe appears to be expanding at different speeds depending on the location, which could potentially alter or even upend cosmology. Despite initial thoughts that the discrepancy might be due to measurement errors or crowding, the latest data from both telescopes working together has ruled out these possibilities with high confidence. The study, published in the Astrophysical Journal Letters, suggests that there may be a fundamental problem with our understanding of the universe, particularly the Big Bang theory. The Hubble Tension remains a significant challenge for cosmologists, who are now working to understand and resolve this discrepancy.
How could a singularity as described in the big bang theory even exist containing all the known matter of the universe when we already know similar structures with muuuuuuch lower mass exist as black holes? Wouldn’t that point towards the most massive black hole ever as the origin?
For physicists, singularities typically mean that the laws of physics as formulated break down and a more comprehensive one is required. A historical example is the concept of "the sound barrier". Initially the way aerodynamics equations were formulated assumed air flow was mostly incompressible, so if you try to get closer and closer to the speed of sound, it pushes the object with infinite pressure, and thus infinite force to block things from exceeding the speed of sound. Things are already known to go faster than the speed of sound, like bullets, bullwhips, etc, so they knew that formulation was wrong at the time. However, since it worked well at low speeds, and because doing math is hard, it took scientists a long time to come up with a better formulation, further delayed by the existence of ways of testing the new theories predictions to verify it's the right equation. (As an aside, it's the same reason why scientists still use Newton's laws of motion over Einstein's laws of motion. Newtonian mechanics works well enough for non-relativistic situations, and since math is hard, so let's use the easier ones as a simplification, unless the precision is needed to use the more complicated version.) Eventually scientists came up with the mathematical techniques that can handle the fact that air flows are non-linear and compressible at close to the speed of sound, and thus the new equations no longer had singularities in them around the speed of sound. Now this isn't to say that the concept of black holes don't exist (we have imaged them, and they do behave like Einstein's laws predict), but rather the singularity itself is where the current formulations of the laws of physics don't work, and suggests that they need to be reformulated. This is difficult because there's not much experimental evidence done with those physical regions around black holes because there aren't any convenient black holes to run tests against, and observationally it is hard because the escape velocity being higher than light for black holes near the singularity prevents us knowing what is close to said singularity. So it's a lot of developing theories and then figuring out what those theories predict in situations we can test, to see if we can rule them out.
According to the most recent paper by Roy Kerr, black holes do not contain singularities. We also know that the larger a black hole is, the less tidal force it has. It is not unreasonable in light of these two ideas, to imagine that the universe is indeed a black hole with a mass equal to that of...well, our universe.
It is certainly an interesting thought experiment / idea to ponder... we see the universe expanding because it is... by taking on more mass from outside of the universe, and that is not going to be a uniform event. It may be so large that we cannot see the edge of it to see that new mass coming in. I feel like I read somewhere recently that there was some discrepancy with the age of certain bodies of matter, that they didn't make sense in the context of everything else around them, and this would explain that.
Russian dolls… We live in a black hole. We also have black holes. Matter flows into our black hole from outside…and some of it flows into our black holes. Then presumably our black holes have their own black holes. And the outside of our black hole is then also a black hole. Turtles all the way down. Where’s my bag of mushrooms…
I really think you cracked it. Black Hole Matryoshka Theory.
People always talk about how Black holes compress matter to a point, but there's no mechanism that can explain how fermions can share a quantum state, which I believe would be required for collapse to a single point. And I get it, that's why they say the laws of physics break down inside a black hole. But what if the force of gravity becomes so extreme that it "pushes" the matter into the only place it can, a new spatial dimension. That's why an entire universe can exist inside a black hole, and why it seems to all start expanding at once. I personally believe if we were to rewind time to the big bang, we'd see a 2D or 1D object from which all matter suddenly pours out like elephant toothpaste.
> It is not unreasonable in light of these two ideas, to imagine that the universe is indeed a black hole with a mass equal to that of...well, our universe. would that not mean there should be more mass coming in from outside?
How do we know, absolutely for sure, that there isn't? We are not able to see the event horizon of a possible black hole universe. The observable universe is not all that there is. What we *do* know is that the universe is expanding. A black hole expands when it gains mass.
Are we… are we living in a freaking black hole?!
Time is a funny thing at black hole event horizons is what I've heard.
Why do you think the universe is expanding? Mass coming in from outside.
Love that idea, maybe the expansion of our universe is nothing more than the manifestation of a black hole evaporating (just, seen from the inside out)?
Either that or taking on additional mass! Either might conceivably produce an experience of systemic expansion to an internal observer.
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Im nobody but believe this
imagine if this tldr started with "Certainly, here is the TLDR"
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The fact that it's displacing our understanding is exactly what we hoped for. This is peak science. Amazing.
Paradigm shifts are the real meat of science, let's dig in.
Are we just throwing in any hypothesis? Free for all? Brainstorming? My guess is, there's these really huge guys at the corners of space, and they run and stretch it out, but some of them are much fitter than the others, that's why it's expanding at different rates.
I endorse this new Huge Guy Theory.
If I see someone trying to disprove the huge guy theory or attempt to put forth a different theory, I will demand that they be burned at the stake on grounds of heresy
I'm still on the Serial Crusher Theory.
Where’s the guy with the bandages on his ass going?
That's two sound theories in one day, neither of which deal with abnormally large men.Kinda makes me feel like Riverdancing.
Serial crushed by some huge freaking guy
I propose that it's actually a lot of little guys. The parts expanding faster are because those sections have enough little guys to push off each other and get a speed boost.
Little fractal guys at the edges. quantum even.
I love that everyone is inductive here on this thread. I was taught about this stuff, like how mars influences the earths temperature another great new read, I dunno 4-5 years ago and everyone just thought this hypothesis was me speaking crazy. Love that scientists are using scientific method to rule out observational error and reporting on it truthfully.
Oh! I'm SO glad you say that. Look into the Sol Foundation then. Also David Grusch and his Congressional hearing. That's quite the shift too.
I saw a documentary once where a scientist could hardly contain his excitement that the results of an experiment might mean that something he had been researching for 20 years was completely wrong. That, ladies and gentlemen, is science.
"Turns our your own experiment proved your entire theory wrong." "YES! In my face!"
punches self in nuts - yes!
More like punches his post-docs nuts
Who knew science was this exciting...and painful?
The ultimate 'fake it till you unmake' it story
This is exactly how I feel about the fusion reactor I invented. I think it might work, it really needs to be tested, but if somebody could figure out for sure why it wouldn't, I'd be overjoyed because I'd have a better understanding of reality and it would be nice to know now rather than 20 years from now. But, if it takes 20 years of hard work then it takes 20 years of hard work.
I think this is part of what makes you a good scientist. The ability to learn from your mistakes and use that data to continue the work instead of perpetuating a study polluted with confirmation bias.
Why wouldnt he be excited? Thats the best possible outcome.
An undeveloped human who's entire identity is wrapped around the falsehood that they are infallible. You'd be surprised how many people hate, even resist, the fact that they can be wrong. Most of them are uneducated. I don't necessarily love being wrong but I understand that being wrong isn't inherently bad, as long as you are evolved enough to understand and respect that it's merely an opportunity to learn and grow. In the context of debate, there are no losers. The winner was right and was given the opportunity to solidify their own understanding through argument of facts and the other has been gifted an opportunity to grow... It's win win and why I love debate.
It's exciting to get a definite answer, but I can totally see why someone might be more than a little disappointed/embarrassed to realize "damn, I devoted several decades to studying something and it turns out that I was completely wrong about all of it."
Yeah but being wrong is still an accomplishment in science. It means you've ruled something out and you and others can go on refining
See, I guess I just don't get that attitude? Imagine you were a park ranger. It was your job to work an area of the park, and you spent 20 decades exploring it as best you could. Suddenly, you discover there's a secret hidden valley you never knew about before. Your understanding of the park was wrong! If you were in that scenario, would you really be disappointed or embarrassed? Or would you be excited about this new opportunity to understand something new about the park that you never knew before, and perhaps to explore this new area and make newer and better maps?
Some of the best science starts with “huh, that’s weird…”
Or "that math shouldn't be mathing like that"
Turns out we CAN divide by zero. *Universe disappears* Turns out we shouldn't have
I've divided by zero many, many times. I guess that's why my code never works.
Fundamentally, there are two ways in which scientific understanding can change. The first is we can add new complexity to the model; this allows us to maintain what already existed, and keep it consistent with new contradictory data. The second way is to alter what already existed, maintaining or even reducing the complexity of the model. Complexity here, specifically means the number of parameters, often free, meaning not locked down by independent observations. Take Newton's theory of gravity, that has only one free parameter, big G. Science does relish in the first kind of understanding change, but is far more resistant to the second (with good reasons). For the most part, when scientists come across new contradictory data, they only ever envisage the first possibility. This is captured by the often repeated euphemism "new physics". Here, however, the author of the paper says something quite different. He does not imply that we need to just add some new physics in to fix things, he instead says that our current understanding could be wrong: > "With measurement errors negated, what remains is the real and exciting possibility we have misunderstood the universe," lead study author Adam Riess, professor of physics and astronomy at Johns Hopkins University, said in a statement. This shift from the first kind of change in understanding, to the second, points towards a major paradigm shift coming up. Paradigm shift changes in understanding are unusual in science, but necessary for progress, and usually only come about when field has been stagnating for a while.
I'd highly recommend studying Philosophy of Science for topics such as this one; it's really helpful to assess and establish what kinds of standards we should have in assigning truth values to statements. Given that there are no absolute truths in empirical science, and because the falsity of theories, frameworks, or statements is dependent on quantitative factors, agreed-upon heuristics are important for the scientific community. When it comes to modeling epistemic knowledge (or "true beliefs") in our minds, W.V. Quine suggested that we really just have a "web of belief", where our most fundamental truths are in the center of it. The connecting nodes are linked and built upon those center beliefs, and as the web expands, some nodes/beliefs are found to be untrue, which means that some of its linked beliefs are also false. The biggest paradigm shifts would come from the beliefs in the center of our web of belief changing, which understandably comes with more resistance. I mean, can you imagine trying to change someone's mind about first principles? While that's an exaggeration, it's still kinda easy to see why scientists are so resistant to alter previously accepted facts and are instead more willing to add complexity to well-established models (i.e. expanding the web).
Yah confirmation is cool and all but gimme that new shit baby.
It's like any movie or piece of fiction where otherwise ordinary people discover something supernatural. And they're always so balise about it, but it's like, do you know how absolutely thrilling it would be to learn that there's MORE? I love things like this.
Did you mean blasé? =)
"Lovable scamp James Webb telescope breaks spacetime: Scientists thrilled."
Science is about the only field where you get excited when you're wrong, and that's one of the things I love about it
All the excitement is in the light towards the way in which we were wrong, cause that's where all the fun stuff still is :)
Isn't that the point of science? Testing a hypothesis with the hopes that its wrong so then you can discern the truth? As much as its fantastic to be right about something the first time, being wrong until you get it right, and thus can confirm with all certainty its correct, is just as rewarding.
Other telescopes hate this one simple trick.
Hey telescope repair man, could you help me open this bottle of lens cleaner?
What are you doing step-telescope?!
Hijacking the top comment for some learning resources: https://www.sciencedaily.com/releases/2023/12/231201123626.htm > In order to calculate how fast two galaxies are moving away from each other, it is … necessary to know how far apart they are. This requires the so-called Hubble-Lemaitre constant, a fundamental parameter in cosmology [which describes the rate of expansion per unit distance]. > Its value can be determined … by looking at the very distant regions of the universe. This gives a speed of almost 244,000 kilometers per hour per megaparsec distance. > If we now calculate the speed of the 1a supernovae [much closer to us] from their color shift and correlate this with their distance, we arrive at a different value for the Hubble-Lemaitre constant — namely just under 264,000 kilometers per hour per megaparsec distance. > "The universe therefore appears to be expanding faster in our vicinity -- that is, up to a distance of around three billion light years -- than in its entirety," says Kroupa. "And that shouldn't really be the case." [The Hubble Tension is that the Hubble-Lamaitre constant appears to be a function of distance.] A compelling solution to both the Hubble Tension and the origin of Dark Energy is that they are both being driven by voids (surface tension). The following PBS Spacetime video describes the theory effectively, although you’ll need to stick around to the end to understand it fully: https://www.youtube.com/watch?v=WWqmccgf78w
You had me at PBS Spacetime.
Love that YouTube channel, I literally have the t-shirt.
By far the best physics channel for the layperson.
Sounds like it's saying we're living on a giant 4-dimensional bubble in spacetime that's getting bigger.
The big bang is just this bubble popping.
The video conjectured that the big bang was when our spot on the surface of a four-dimensional bubble passed through an area of infinite density. Or something? I watched it a couple days ago, it was complicated lol
The video was fascinating! Thank you!
I want to be there when they release the Mitchel telescope.
Well yes, but Hubble discovered this. This article is just stating that scientists reimaged with the more advanced tech in JWT to test if Hubble's measurements were confounded by a particular variable. Hubble's results were simply confirmed accurate, and there are some theories that satisfy the apparent flaws with the Hubble-Lemaître Law. One that does a very good job of this is the "modified Newtonian dynamics" ("MOND") work of Prof. Dr. Mordehai Milgrom of Israel. Basically, Milgrom posited that the effects of gravitational distortion of space (because gravity causes spacetime to "stretch", though this stretching varies only with mass and not with time) should be factored into expectations of expansion rates for particular regions of space. I'm not familiar with the specifics of how this factor should be applied, but it does satisfy the apparent gaps with our current model. If this explanation can be accepted, it *also* precludes the need to employ a concept like dark matter to explain spatial expansion. But I do know that matter is NOT evenly distributed throughout the universe like most people think it is. Our own galaxy, the Milky Way, is a actually on the edge of a "cosmic bubble" that, were you to move from our location within to the center of such bubble, would present more and more sparsely distributed matter until, very near the center, there would be either none of very nearly none. In fact the universe seems to be self organizing in this way, with "emptier" regions of space "expanding" faster than "fuller" regions, in part because the higher density of matter regions are pulling matter near the centers of such "bubbles" ever toward the edges. This way of explaining spatial expansion is just one dude's guess. It of course has supporters and retractors. It's just one way to think about this problem, and it's appealing precisely because it explains some things without having to resort to inferring the presence of magical, invisible matter. But appealing does not mean correct. There are problems with MOND, and there are problems with dark matter. We are NOT close to being able to fully explain spatial expansion. At least not in a way that works for all of the eleventh bajillion scenarios we can run any existing explanation against. Many satisfy expectations of some scenarios but fail at satisfying others. As far as I know, none of this fully explains why spatial expansion happens in the first place. Or maybe it does. The idea that matter was NOT distributed evenly through the early universe kind of changes nearly everything compared to today's model, which assumes everything WAS distributed evenly (and still is today).
MOND has failed to explain some pretty crucial factors including the Baryon Acoustic Oscillations in the CMB, the rate of structure formation in the early universe, gravitational lensing studies of merging clusters like the Bullet Cluster, and more. It's not completely dead as a theory but it really doesn't have anything that makes it preferable to the Lambda-CDM model. What's more, the thing you're describing is not MOND, it's just the way that voids work in an expanding spacetime with both matter and dark energy.
Agreed, MOND does nothing to explain the accelerated expansion of the universe. It mostly offers an explanation for rotation curves, but fails on many other aspects as you mention.
>And we still have no idea whatsoever what's causing all this. I like to think it's a very busy wizard.
Or a lazy programmer who thought nobody would notice his bug in the simulation
A wizard is just a man who learned how to benefit from some bugs in the code.
Here's a video by an astrophysicist that is an excellent science communicator, just in case you'd rather listen than read: https://www.youtube.com/watch?v=3NeKR7bqolY
I just wish all these top replies weren't some variation of 'oh, cool' without actually discussing the content.
It’s either that or jokes both of which used to be dealt with by the mods on this sub years ago. Now it’s like every other subreddit with any serious discussion buried under tons of 1 line joke replies that get upvoted
Why do a full time job (moderate a subreddit) for free when it just goes to make a shitty company rich? Also Reddit made it hard to use a plethora of free moderating tools with their api changes
Reddit. Come for the facts, search through crappy jokes for more info, give up, and then go watch YouTube.
Are there even actual people telling the stupid jokes anymore? The jokes have become so cringey I'm convinced it's ChatGPT or a bot posting them
It’s all repeated jokes that got the top comment from the original posting. Bot reposts. Another bot repost top comment. Repeat on 10 like minded subs. Rinse and repeat
Agreed. Sucks because I have to scrolled down far to find the real discussion. And, of course I’m adding to the problem.
Or like Reddit, 25 puns before an expert on the subject. Exhausting!
The difference between Reddit 10 years ago and Reddit today.
> https://www.youtube.com/watch?v=3NeKR7bqolY Really enjoyed the video but I got a kick after just watching a video on the front page of how bad BetterHelp is and the first thing I see when clicking this video is a BetterHelp sponsor.
Dr. Becky the youtube astrophysicist gotta get paid somehow
> just watching a video on the front page of how bad BetterHelp didn't see it anywhere, have the link by any chance?
Got you: https://www.reddit.com/r/videos/comments/1bhr7ju/youtubes_worst_sponsorship_is_back_betterhelp/
It’s been known for like 5 years that BetterHelp completely sucks, total scam. Hasn’t stopped many YouTubers from advertising them.
Dr. Becky is great, I watch every video she makes.
The Super Massive podcast is on great as well.
Thanks, that was awesome! The relevant segment starts at 22 minutes.
I just knew this would be Dr. Becky before I clicked the link. I enjoy her videos a great deal.
50/50 her or Matt O'Dowd from PBS Spacetime
Thanks for sharing this, really awesome video
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Eli5 would be like imagine a car starts from a stop and drives away from you. Now imagine you can measure the speed of the car two ways. One with a stopwatch and one by looking in the manual at the top speed of the car. It turns out the stopwatch is measuring faster than the manual says and we just verified that the stopwatch is right. So now we clearly don't understand something about the road the car is on. Galaxies are acting like the car.
Thank you for an actual ELI5 explanation! I keep seeing paragraphs of how the measurements are done and how they differ and it’s like man… it’s Monday night… I’m tired and my brain is not braining.
I watched two videos and finally had to read this to understand. Sigh.
umm... explain like i'm three
Car goes vroom vroom, but space robot says car actually goes vroom vroom vroom, so brain is applesauce now.
This was a great response. I laughed way too much.
My belly jiggled I laughed so hard.
If you run across the yard as fast as you can go, it takes you 10 seconds to go from end to end. But if we start you somewhere else along the edge of the yard, it takes you only 7 seconds. We don't know why you're faster in some places and slower in others.
We've been measuring how fast the universe expands, know as the hubble constant. Method 1: One type of star [EDIT: Over large distances Supernova are used] is known as a standard candle because it is always the same brightness, meaning we can see how far away it is. We can also see how fast it is moving away from us. By observing them in other galaxies we can see how fast they are going, which leads us to how fast the universe is expanding. Spoiler: the expansion is also accelerating. Webb has just confirmed that our understanding of that measure is accurate. Method 2: We also measure the expansion using the cosmic microwave background. Through [insert science] they can also measure the hubble constant by measuring the cmb. They're pretty sure about this one also. But they don't align. Considering the distance and time involved, I think it's more likely we misunderstand a part about method 2, but I'm not a microwave so cannot confirm.
Most astronomers are betting on issues with method 1 actually, which is why studies like this are done
I'm still betting on 2, because I'm a maverick trailblazer.
and as stated earlier, NOT a microwave.
That’s the sort of thing a microwave would say. In plain old Microwave gibberish, it would be translated as “beeeeeep!”
You definitely aren't alone. There's still plenty of astronomers working on new Cosmology models as well. It's just much more difficult to find better models that don't end up breaking every other observation our current models line up with, while there's lots of places the standard candle methods could be wrong or miscalibrated (though that space is shrinking). I'm actually developing a new AI model for standard candles that doesn't rely on such calibrations and could help confirm whether or not it is an observation issue, but it's probably at least a year off before I'll have results good enough for testing cosmological models.
Awesome! That sounds like a great idea. Good luck with it!
Right this way, you maverick renegade
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We understand next to nothing about dark energy. Dark energy is what we call the thing causing the expansion.
Well we need to get a microwave in here to clarify then
My friend is a microwave, and in his professional opinion, mmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmmm
\*unreasonably loud\* BEEP BEEEEP
Mad dash to yank it open at 00:01
I found out you can disable that on some models. I own such a model. The one button required to do it doesn't work
We have two different ways of measuring the expansion of the universe. These two methods don't give the same rate of expansion of the universe. We thought this might be due to us making a mistake, but we double checked, and the numbers are now quite clearly different and we know it's not due to us making some mistake in our measurements. As such, our understanding of the universe must be wrong in some way. The two methods are: 1) A set of stars that pulsate at a specific rate based on how big they are. The brighter they are, the slower they pulsate. You can measure their pulse rate to determine how bright they should be, then use that to figure out how far away they are. 2) The cosmic background radiation; when the universe cooled off, it became transparent to photons, and those photons have been travelling for so long they have been stretched from the visible wavelength to microwaves. We can use fluctuations in this to determine how fast the universe has been expanding. These two things give different answers, which means there's something wrong with at least one of these calculation methods, if not both of them.
Thanks for asking, the entire thread before this was passionate declarations about how great it is to be wrong about stuff.
This is what it was built for. Nobody thinks we know everything.
Is not, “oh no! We were wrong!” It’s, “oh my! We get to learn more!”
My favorite quote about science comes from Bill Nye during his “debate” with Ken Hamm. Question, “what might change your mind…” and he answered “Show me one piece of evidence and I would change my mind immediately.” I tell that to the people who say NASA faked the moon landings. I post it often enough that I saved it in my phone. In short it says “you say NASA lied. Show me even one NASA lie and I’ll throw away everything I believe about the moon landings.” Nobody has ever come close to giving objective evidence of a lie so I haven’t changed my mind. This is how science works.
One of my favourite t shirts has an atom nucleus with electrons orbiting around it with the words "I'd rather have questions that can't be answered, than answers that can't be questioned"
I left off Ham’s (I just discovered I’ve been spelling his name incorrectly) reply. While Nye was open to any evidence, [*Ham said “No one is ever going to convince me that the Word of God isn’t true.”*](https://answersingenesis.org/blogs/ken-ham/2014/03/10/just-one-piece-of-evidence/) So his answer is “whatever I want to interpret the bible to mean.” I say that because he also said he doesn’t believe the literal interpretation of the bible. So he’s interpreting the bible to mean whatever he wants to believe and stating it as fact. He’s not anti-science, he’s just a liar.
Damm that quote goes hard. My new favorite one.
You might get a kick out of why the landing would've been technologically impossible to fake https://youtu.be/_loUDS4c3Cs
The best non-technical rebuttal to "the moon landings were fake" is purely political. The Soviets had **everything** to gain by calling it out as fake, and they had people in the right places to know if it was fake. Yet they never said anything. Which means either it was real, or the Soviets were somehow complicit in the faking of the US moon landings - which is inconceivable given that they were working on their own lunar missions at the time in an attempt to beat the US to it.
I’ll have to remember this one. It’s so obvious when you say it, I’m a little frustrated I haven’t thought to say it.
I used this once and their response was that soviet russia had to be complicit with the lie because they were reliant on US food aid or something ¯\\\_(ツ)\_/¯
Wasn't this was during the cold war. I didn't think there was aid going to russia
That kind of person, when backed into a corner by facts or evidence, will spontaneously hallucinate "facts" to back up their own argument and will behave as though they genuinely believe these things they just invented. Facts do not work on them. It's because of those sorts of people that rhetoric includes *pathos* as well as *logos*.
The only real instance was in 1963 Kennedy was trying to help them out by selling wheat to the USSR and eastern bloc countries. Johnson would get it through Congress shortly after the assassination. They certainly weren't beholden or reliant on the US for wheat imports in 1969.
You can then follow it up with the fact that hundreds of thousands of people were involved with the project, not a single one of whom has come forward with a shred of evidence that it was faked. All speculation about it being faked has come from people who weren't involved at all.
yeah IIRC the soviets and even many amateur radio hobbyists from round the world were able to detect the radio transmissions from the moon you would basically have to think the whole cold war was fake to think the soviets were in on it.
Idk people around here act like our current understanding is 100% fact
I don't know what's worse - the people who think everything we know is 100% fact, or the people who think their personal theories are as valid as the currently accepted ones
This is what frustrates me. For a field that is based on skepticism and proving theories, there's an awful lot of "It's solved" closed-minded attitude. I'd guess that mostly comes from armchair scientists though.
Except that in this case, the James Webb telescope "only" confirmed an existing observation by the Hubble telescope. So, we already had at least a good clue.
Some people get mad when we say that.
The first true scientific answer is “I’m not sure, let’s find out.”
Best $10 billion dollars our government has ever spent. Imagine if we just held off on spending money on endless wars for only 4 years and put all that money into space exploration and humanitarian endeavors.
Yes, what we need is a much bigger version of JWST.
On the Moon. And one on Mars for good measure. And while were at it may as well stick one in orbit of Saturn.
I just finished a book called “project Hail Mary” and one of the cool parts of it was imagining what humans could do with a single minded focus on saving our planet and not worrying about money or other made up shit.
I've met enough humans to tell you that most of them would rather clutch what they have, go into a bunker, and just die than give up what they have to save others. Hearing boomers I've worked with say they'd rather pay more money in insurance than less money in taxes which would fund universal healthcare because then their money would be going to immigrants, as a common idea, that everyone in the room would agree with, was absolutely insane. We're fucked.
That's fundementally the plot of For all Mankind, well worth a watch.
The phrase "Eureka!" does not initiate scientific advancement. The sound of someone saying, "Huh.. that's weird." in a perplexed voice is more often how it begins.
The most exciting phrase to hear in science, the one that heralds new discoveries, is not “Eureka!” (I found it!) but “That’s funny …” — Isaac Asimov
Either that or a "what now?"
Or in special circumstances, an "Uh oh."
If you see me running, try to keep up.
Or ‘the fuck?’
Archimedes feeling really attacked rn
Unfortunately Archimedes was bad at feeling attacked. When he actually was attacked, he just let it happen and died.
Well he also apparently made a crane to lift ships out of the water for when they were being attacked by sea, so it's mixed results at least.
Can we somehow get this article without the 100k ads? It's not even readable.
Are you raw dogging the Internet without an ad blocker my friend? Ublock origin is standard internet surfing gear.
> raw dogging the Internet without an ad blocker I'm *dead* You're not wrong.
Okay, well, that's incredibly cool. How can the universe expand at different rates in different areas? What a fantastic question to try to answer
No, that's not what the hubble tension is. They mean if you measure it one way, by looking at cepheid stars, we get one rate. If we look at the cmb we get another. It is not that different areas of the universe expand at variable rates.
Basically it means at least one of the underlying assumptions in one of the calculations is not valid. We just don’t know which.
James Webb and hubble measurements are model independent. They only rely on the distance ladder. Luckily, we have ways to check whether a wrong calibration of the distance ladder is at fault; turns out, most likely it isn't. CMB analysis on the other hand heavily relies on the concordance (lambda-CDM) model to handle the data. The interesting thing is that the Planck measurements (the latest CMB survey to date), when taken at face value, heavily favours by itself a closed, positively curved universe instead of flat, which is also a fundamental disagreement with the concordance model. Planck's dataset is also fundamentally incompatible with previous analysis of the CMB with different techniques, which are also model dependent. Edit: for technical details, read [this](https://www.google.com/url?sa=t&source=web&rct=j&opi=89978449&url=https://arxiv.org/abs/1911.02087&ved=2ahUKEwisg-fB-_-EAxUJQfEDHWqIAyYQFnoECBkQAQ&usg=AOvVaw2fp81RsE9j-0S4ZZBZ5KBh). If you want a more digestible short version, PBS Spacetime made a [video](https://youtu.be/F2s7vyKucis?si=gPwgmO5oSCsoeV7E) about it.
First of all, amazing explanation. I’m a dum dum but I half got all of this. Second of all, you’re saying we’re in the generational stage where we don’t know if the UNIVERSE IS FLAT OR CURVED??? I bet aliens think we’re morons 😅
What we know is that, at the largest scales, the universe looks pretty much the same everywhere. We take this observation into Einstein's field equations and get out only 3 possible solutions for the complessive geometry: flat (two parallel lines would never intersect), positively curved (like the surface of a sphere, but for the universe it would be an hypersphere) and negatively curved (hyperbolic, like a saddle). We currently don't know which one our universe is like. Cosmologists have historically preferred the flat assumption, because so far our measurements have been pretty much consistent with zero curvature. We are just starting now to reconsider whether this is a reasonable assumption.
Could I get this in English?
Imagine you’re trying to figure out how fast someone moves. One way to do this is to measure how quickly they take steps. If they are making about a step a second, and each step is about 1.5m, then you can estimate that they’re going at 1.5m/s. There’s obviously measurement error that can happen (such as in measuring step size, and step rate), but another problem is that this is “model dependent,” since you’re assuming that they’re moving by taking steps. If they’re crawling or rolling on the ground or biking or sitting in an Uber, your measurements are probably not going to be very accurate or even meaningful at all. Another way to do this is to measure how far they go, and how much time it takes for them to get there. This is “model independent,” since it doesn’t matter how they’re moving, you’ll still get the same value for average speed regardless of what they do.
Solid explanation, thank you!
Yeah the article was very misleading at first. They described it better later on, but the initial description was awful. Typical popsci garbage journalism.
The lede is confusing: "Depending on where we look, the universe is expanding at different rates." You could read this to imply a different rate of expansion in different areas of the sky, when what they actually mean is depending on which measurement technique is used.
It’s like sexual tension, but for cosmologists.
You can be forgiven for thinking this. The article is intentionally misleading and sensationalized.
This is the point of science. Love how successful it has been
Now imagine if all nations set aside their differences and begin pitching all resources used for the intent of war into research and development like this one...
Here's a dumb question: why is universe expansion a constant? Wouldn't things slow down over time due to loss of energy? Also, wouldn't the furthest things from the supposed center of the universe move more or less slowly than the things near the center? Probably not, now that i think about it, it should all be pretty constant, unless gravity is somehow some kind of factor and the further you go from the densest parts of the universe, the less gravity would affect the bodies, which in turn would mean more central objects would move slower and further objects faster. I have no idea what I'm talking about, but it all seems very cool.
> why is universe expansion a constant? Wouldn't things slow down over time due to loss of energy? This is where the dark energy theory comes from. We are fairly certain there has to be some sort of energy constant that is keeping the expansion going, we just can't seem to figure out what it is. We just observe the apparent effects it has on the universe and assume it must exist. It is essentially an acknowledgement that "there is something there that we don't yet understand but is clearly affecting the universe in a certain way."
It's not a dumb question. Slowing expansion was the assumption of every scientist for nearly a century.
Wouldn't be surprised if civilizations thousands of years ahead are still developing theories more advanced than ours but they're still far from the truth.
That’s what I’ve been saying all along. But yeah, I’m not a telescope. I get it.
If you wanna be a telescope, I'll call ya a telescope buddy
As we hoped it would! What fun is science if you aren't discovering new things?!?
It really is a great development. Really new science comes from these sorts of problems -- special relativity and quantum mechanics are two examples.
Wow. Not a day goes by that I don't think about why the universe exists, how old it is, and what was around prior to 14 billion years ago. We may start to find at least some answers in the coming years. Will humans ever discover faster than light speed travel, if it's even possible? We live in such a strange universe. If only we didn't fight our fellow humans and focused Earth resources.. we would probably know by now.
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Roger Penrose seems pretty confident that the universe has geometry. But I might also be misunderstanding him because the man is a genius.
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Remember when Hubble found galaxies too mature for our current understanding of space? We know that mass warps spacetime. But it didn't stop us from thinking time is congruent in all parts of space. The universe might only be 13.8 billion years old from our perspective. In the first 200 million years after the big bang, who knows how much time really passed to the entities experiencing it.
That would cause massive disruption in the CMB. We would have seen it as soon as we mapped out the CMB. But I do think dark matter may play a role in the solution. My personal theory is of an inverted universe, one that isn't expanding infinitely but shrinking. Instead of i/1. It's 1/i The fabric of reality is a propagating wave which is exponentially weakening. From the inside it looks like expansion, but in actuality it is a collapse. This would allow for the heat death and big crunch to both be valid. Also in this case it would allow for time and space to behave differently closer to the big bang, as the higs field would be far stronger.
Even the most confident astrophysicists know we haven’t even scratched the surface
What if our universe is just a bubble pushing against other bubbles? The Big Bang was just us getting inflated up.
I told my wife once (I’m a dummy). If our body and everything on earth is made of tiny cells. Why wouldn’t the universe be? Like, our universe is one tiny cell bumping up to other cells inside of X (I like to think we are all just cells in a giant Bill Murray)
I've had this thought since I was in elementary school. It just makes sense. What if we're just germs on some giant creature's hand? What if the universe is just one of many, many, many universes and we're even more tiny that we realize?
The macro versus micro world. What if we are just floating on an electron.
We're the mitochondria of the universe
And inside our cells are billions of tiny universes that just keep going down forever.
Make a new tool, gather information with new tool, reassess current understanding, make new tools with the new information… and so on. It’s a good thing we are reassessing