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James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

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Re: James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

#91
post #85

Earlier quoted context omitted.

The balloon analogy is a 2 dimensional example. If you are on the surface of the balloon, there is no "edge". You can go forever in any direction. If the balloon is inflated, it doesn't expand into something (remember we're in a 2D space, it's not a 3D balloon), it "expands into itself". If you drew two dots on the surface of that balloon, those dots would get further apart as it inflated. What did those dots expand…

> The balloon analogy is a 2 dimensional example. If you are on the surface of the balloon, there is no "edge". You can go forever in any direction. If the balloon is inflated, it doesn't expand into something (remember we're in a 2D space, it's not a 3D balloon), it "expands into itself". I'm talking about 3d that we live in. We're currently standing on a ball of dirt, if the earth started to swell up, the surface w…

You can imagine the balloon’s curved surface geometry without assuming that it is embedded into a 3D space. This is what Riemann discovered in the 19th century. Such a non-embedded space is called a manifold. In the case of the balloon, it’s simply a non-Euclidian two-dimensional space. A third dimension doesn’t enter into the picture in that formulation.

Four-dimensional spacetime is considered such a manifold. Its three-dimensional space “slices” are predicted to expand with time by general relativity (first predicted by Alexander Friedmann in 1922), and actual observations have confirmed those predictions.

Re: James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

#92
post #85

Earlier quoted context omitted.

The balloon analogy is a 2 dimensional example. If you are on the surface of the balloon, there is no "edge". You can go forever in any direction. If the balloon is inflated, it doesn't expand into something (remember we're in a 2D space, it's not a 3D balloon), it "expands into itself". If you drew two dots on the surface of that balloon, those dots would get further apart as it inflated. What did those dots expand…

> The balloon analogy is a 2 dimensional example. If you are on the surface of the balloon, there is no "edge". You can go forever in any direction. If the balloon is inflated, it doesn't expand into something (remember we're in a 2D space, it's not a 3D balloon), it "expands into itself". I'm talking about 3d that we live in. We're currently standing on a ball of dirt, if the earth started to swell up, the surface w…

The universe is everything. There's no outside the universe, since whatever that "outside" was would also be part of our universe. It's not empty space, since that too would be part of the universe. There is no edge of the universe since that would imply that there is something beyond that edge. In scientific terms, the universe is homogeneous and isotropic.

We've proved the universe itself is getting bigger, which means that yesterday it was smaller and the realization of that fact was how the big bang theory came to be.

There are lots of resources out there if you want to build an intuition around how a universe that's everything can get larger without needing something to expand into.

Re: James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

#93
The [Study] has a better framing in its title "JWST Observations Reject Unrecognized Crowding of Cepheid Photometry as an Explanation for the Hubble Tension at 8σ Confidence".

It rejects the hypothesis that there was a systematic observational problem in observing Cepheid variables (CVs), which are in turn used to estimate distances to Type Ia Supernova (SNs), towards a long-term goal the Study concludes with of "Tying all of these together by observing large samples in common can lead to the calibration of ∼100 [SNs] and a Notably the paper doesn't provide a new estimate of H0, but it does strengthen the case for CV/SN being at odds with other methods of estimating H0, a problem called the Hubble Tension.

JWST was built primarily to extend the sensitivity range for infrared observations, so we can see fainter sources from further away, or near sources with greater resolution. This study is about the latter.. the study of CVs and SNs in nearby galaxies.

"the significantly greater resolution of JWST over [Hubble Space Telescope] has greatly reduced—in practical terms, almost eliminated—the main source of noise in [Near-Infrared] photometry of [CVs] observed in the hosts of nearby [SNs]. The resolution of JWST provides the ability to cleanly separate these vital standard candles from surrounding photometric "chaff."

CVs and SNs are "standard candles", rungs on the Cosmic Distance Ladder[CDL], the framework we use to compare and contrast different astronomical distance measurements. The term "standard candle" is used for a physical process we think we understand well enough to use its appearance at astronomical distance to infer other properties of its observation, e.g. the candle's color shift towards red the further away it appears to be. ("appears" since we can't directly measure actual distances, but observe that galaxies get smaller/fainter/redder together)

Cepheids are a relatively common kind of star that pulsates regularly during its lifetime, while SuperNovas are much rarer one-time very bright events. SNs are really useful to see them far away bc how bright they are, but since there's so few of them, we calibrate nearby SN distances based on the many CVs in the host galaxy of the SN.

In all, this study starts by looking at CVs in NGC 4258 at 23 Million lightyears away, and then looks for photometric crowding of CVs at successively further steps away in NGC 5643 (41 Mly), NGC 1559 (48 Mly), NGC (1448 56 Mly) and NGC 5468 (140 Mly), but don't find evidence of crowding to account for apparent brightness/closeness of the CVs, so rejects that idea with a high confidence. Those galaxies are actually as far away as they appear to be if CVs are good standard candles.

These are at the nearer end of the CDL.. 140 Mly vs the observable Universe is thought to be at least 13 billion light years radius. But if it in turn makes us more confident about SNs, those go out to a current max of 16Bly[FarthestSN].

[Study] https://iopscience.iop.org/article/10.3847/2041-8213/ad1ddd

[CDL] https://en.wikipedia.org/wiki/Cosmic_distance_ladder

[HT] https://xkcd.com/2516/

[FarthestSN] https://en.wikipedia.org/wiki/SN_UDS10Wil

Re: James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

#94
post #61
post #57

Earlier quoted context omitted.

Please enlighten us.

Wouldn't it be easier to just go take a look at the wiki article? Or even to type "is the big bang an explosion" into your search bar?

I like how the primary rebuttal is my use of a non-standard academic term on a public forum non academics read. Hear that unzipping sound? That’s reality itself coming apart because the Jedi Sacred texts were not recited from just so.

Really just proving my point that academia is obsessed with little more than normalizing symbolic logic. Such conservatism and thought policing is en vogue across social contexts these days.

I earned a BSc in EE and bailed on an MSc in elastic structures as such notions about academia seemed pretty obvious to me all the way back in the 90s. It’s all mathematical generalization of how matter coalesces at speeds relative to light, arguing for such specific recitation of truth is the problem: you aren’t owed that. The “human” language aspect is arbitrary to me, but often seems to convince the public some BS is immutable physics only for the BS to be falsified decades later.

Scientists do a whole lot of saying what they promotes them, damn the externalities. Has more in common with our economics in that way; can human scientists coupled to human nature to keep their meat suit alive escape such a bias?

I’m not anti-science, I’m anti-contemporary institutions. Only 14% in the US hold more than a bachelors, yet their influence is wide and deep, and (charitably) forever incomplete. A minority have outsized influence over everyone yet their so-called discovery is often restatement of a well known phenomenon or just wrong, damn the externalities.

Resolving all scientific inquiry (I’m sure someone will take offense such specific an idea can exist; academics like to flip flop between arguing for generalization and specificity like typical humans) would mean knowing all states of all matter and energy. Physically impossible, there will always be “holes”. Outwardly academia is dishonest in that regard, and the incompleteness of their work. IMO out of fear society would turn against them. Probably rightly so.

Science is important. I’m not anti-science. I’m anti-institutions manipulating the actually innumerate into serfs based upon (charitably) incomplete and more often than not, outright wrong conclusions.

Academics want to go on about non-experts being wrong and their egos. Well academics are humans mired in the same human condition. Turn the mirror around.

Re: James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

#95

I get that the universe can be expanding, and that there might be different methods to calculate/measure this that have discrepancies. But that the rate of expansion is accelerating , how in the world is that possible?

You should ask how fast the expansion is.

Re: James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

#96
post #41

Earlier quoted context omitted.

The fact that you seem to be interested enough to email experts about ancient galaxies, yet still are referencing the big bang as an explosion, leaves me utterly confused about your level of knowledge, but leaning heavily towards "no idea what they are talking about". The big bang was not an explosion.

Oh I’m sorry on an open forum where I don’t know every reader I use casual language. This isn’t a forum for PhD defense. So glad the takeaway is about a single word. While the idea that researchers are failing left and right which reaches into everyone else’s lives is left untouched. Likely because you’re the sort that relies on people buying the con about your efforts. Reality is not a neatly organized set of decoup…

Yeah, spinors.

Re: James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

#97
post #54

Earlier quoted context omitted.

The fact that you seem to be interested enough to email experts about ancient galaxies, yet still are referencing the big bang as an explosion, leaves me utterly confused about your level of knowledge, but leaning heavily towards "no idea what they are talking about". The big bang was not an explosion.

>The big bang was not an explosion Okay, then lets hear your interpretation of what it was.

A spinor?

Re: James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

#98
post #47
post #16

Cosmology feels a lot like quackery these days. Does it even bother to rely on physics? Physical experiments show explosions do not propel all matter at the same rate. James Webb telescope recently found galaxies that were “too old”, would have formed right after the Big Bang. The prevailing wisdom was all matter spread out evenly due to the Big Bang, then coalesced into galaxies (I emailed various researchers to con…

> Just more evidence the well educated (I assume if it’s concensus driven even the best educated agree) are just typical people and their expertise should be challenged constantly rather than sit back and assume things are figured out. As someone who worked as a cosmologist, I have trouble putting into words how wrong, out of touch and arrogant this statement is.

In my social scene are people who worked at Fermilab, whose work helped inform where LHC should focus its search for the Higgs. A PhD EE who has designed chips you use. The list is long.

A lot of my insight into academia (since it’s been almost 30 years since I graduated and left it behind me) is influenced by academics tired of and often disgusted by their peers dishonesty about their work. Theory after theory have more in common with religion; they were made up.

Historians in my social scene say there’s solid historical evidence advanced degrees were invented as a payola scheme between landed gentry and the church; money for BS theology degree the illiterate public could not falsify. Over specialization doesn’t really make net new discovery so much as normalize old ones, but we keep up the role-play of history and anoint geniuses and the like.

Give them resources and prestige to do some math. Grigori Perelman would like a word on what’s required resource wise to do math. Out of touch and arrogant westerners.

Similar trend going on these days where the innumerate serve BS they cannot begin to try to falsify. Just so happens much of it isn’t reproducible anyway, but the can’t argue that or the out of touch egos of a minority of the populace that make up academia would crumple in outrage.

Offense at minor slight is so endemic to human nature, so general an emotion it impacts all of us.

Out of touch and arrogant is applies just a neatly to academics being normal humans and all.

Re: James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

#99
post #86

Earlier quoted context omitted.

It doesn’t expand into anything. It has no edge. It expands within itself, like it’s distorting itself. Alternatively, you can picture it as groups of gravitationally bound objects (= galaxy clusters) moving away from each other everywhere in the universe. It’s a bit like raisins in a cake being carried away from each other by the dough expanding in the oven. Where the cake already fills all space infinitely in all d…

> It doesn’t expand into anything. It has no edge. It expands within itself, like it’s distorting itself That's not an explanation, that's incoherent ramblings that make zero logical sense

To paraphrase Feynman, I can't explain to you how the universe expands in terms that you are familiar with because I don't understand it in terms that you are familiar with.

https://www.youtube.com/watch?v=MO0r930Sn_8

It takes effort to understand those fundamental terms, so if you want to understand this, you'll have to meet people halfway instead of rejecting how somebody is trying to explain something to you.

Re: James Webb Telescope Confirms That the Universe Is Expanding at Different Speeds

#100
post #16

Cosmology feels a lot like quackery these days. Does it even bother to rely on physics? Physical experiments show explosions do not propel all matter at the same rate. James Webb telescope recently found galaxies that were “too old”, would have formed right after the Big Bang. The prevailing wisdom was all matter spread out evenly due to the Big Bang, then coalesced into galaxies (I emailed various researchers to con…

Aggressive dismissal of an entire field with minimal attempt made to understand it is never going to play well and following it up with sarcasm doesn't improve the situation. Attempting to work backwards to the beginning of the universe from a single tiny point in time and space is fairly obviously going to be a lot harder than understanding the physics of events we can repeat, measure, and examine. This doesn't make…

That’s exactly my point though; it’s incomplete but academics sell incomplete/wrong work to eat.

They’re just as much avoiding real work of keeping themselves alive as an aristocrat to noodle around something that will only ever be incomplete due to our axiomatic systems being leaky abstraction.

I’m a “Perelmanite.” The ethical and communication standards of academia serve its social influence goals, not science.

We get the gist of natures mechanics and know how to measure generally. Further specialization of the syntax rarely moves the needle, which still points at Einstein, Gödel, and other century old works, rarely the contemporary librarians of scientific texts except to say “yeah this customization still preserves the whole of relativity” or some other core body of work we infer modern research form.

Perelman figured out Riemanns at home, alone. Bailed on university as he found it mired in politics and manipulation of social agency to preserve itself.

See that recent article about institutions becoming road blocks to the progress they were created to resolve. There’s been article after article here about science depts veering into pseudo-science. When a workers salary depends on them ignoring truth… “meat suit needs to eat” wins above honesty and integrity.

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