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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

#41

Post by gagaJo »

Workaccount2 wrote: post #36
gagaJo wrote: 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…

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 decoupled microservices. It’s a monolith and bad science radiates through our lives.

Experts should not have the influence over society they demand.

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

#42

Post by epgui »

gagaJo wrote: 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…

You're so lost I'm not sure where to start.

Not that you really deserve help, with that attitude...

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

#43

Post by mr_mitm »

nabla9 wrote: post #2

This result has 8.3-sigma confidence, so it's as good as it can get statistically. Even greater confidence than that of the Hubble tension itself. The Hubble Tension is real. The expansion of universe is accelerating.

> The expansion of universe is accelerating.

We knew that before. This goes deeper than that. It accelerates in a way that cannot be explained by a constant dark energy density, which is part of our standard model. We have plenty of alternative models that can explain this, but our measurements are not precise enough yet to rule any of them out. Hopefully Euclid will provide data that is.

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

#45

Post by nabla9 »

cl42 wrote: post #6

Can someone more familiar with the science help me out? - On the one hand, the universe can be expanding at different rates. - On the other hand, is it possible our approach to measuring the expansion (e.g., using Cepheid variable stars) might be the problem?

Unless there is a "cosmic conspiracy" where Cepheid stars work differently when the distance from earth increase, that's not likely.

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

#47

Post by mr_mitm »

gagaJo wrote: 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.

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

#48

Post by epgui »

m3kw9 wrote: post #28

I thought universe is infinitely large, how is it expanding

I'm not sure if we know that the universe is infinitely large.

I do know[1] that:

- it's larger than we will ever be able to know or observe (ie.: the observable universe is smaller than "all of the universe"... although that feels a bit hand-wavy to say)

- it's expanding.

---

[1] I am a scientist, but not a physicist. Everything I said could be wrong.

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

#49

Post by komali2 »

xyzelement wrote: post #14
spenczar5 wrote: post #7

Earlier quoted context omitted.

I don’t understand what “time does not flow the same everywhere” means. Can you elaborate?

I don't want to discourage question-asking but you're now asking someone to give you a background on a physics phenomena without them knowing your starting level. It's awesome that the poster you're replying to introduced a new concept to us (not something I was thinking about, either) and literally taking the thing you quoted: "time does not flow the same everywhere" into Google will give you a starting point for yo…

First search results:

https://www.quora.com/Does-time-flow-at-the-same-rate-everyw...

Quora side-paths:

> no, gravity

> no, speed and gravity

> no, gravity and velocity, look up time dilation

> yes, time is constant, however it is relative for observers

Second:

https://www.scientificamerican.com/blog/observations/do-we-a...

A fun exploration of what it means for time to flow, and how we don't really have observational personal evidence of time flowing (at a constant speed or at all), we just have our memories. Seems relatively unrelated otherwise.

Third:

https://medium.com/la-mia-biblioteca/does-time-flow-cafaf084...

Appears to be someone advertising a book.

Fourth: (i don't recommend this link)

https://www.express.co.uk/news/science/738387/Time-NOT-real-...

Horrible shit article chock full of video ads about the same issue as link 2

Conclusion: It's ok to ask people what they mean when they say things. It's unreasonable to expect a google search from your listeners after you say something.

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

#50

Post by layer8 »

nabla9 wrote: post #11
wrycoder wrote: post #3

Earlier quoted context omitted.

They confirmed[0] that the Hubble Tension[1] is a valid discrepancy between the two different ways of measuring the expansion of the universe. [0] https://iopscience.iop.org/article/10.3847/2041-8213/ad1ddd [1] https://en.wikipedia.org/wiki/Hubble%27s_law#Hubble_tension

Two different ways in two different times in the lifetime of the universe. expansion rate in the early universe -> accelerated expansion .

No. The fact that the expansion is accelerating was already established by supernovae measurements alone [0]. The Hubble tension is about the degree of acceleration, not about whether there is an acceleration or not.

[0] https://en.wikipedia.org/wiki/Accelerating_expansion_of_the_...

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