Violating the cosmic speed limit is not only not a "perfect model" it's an atrocious model. Wouldn't you agree? It's a model that incorporates hard contradictions to itself.
You are saying I'm a lay person? You nailed it. I'm quite curious though about what would be so "advanced" that pop-science writers would not want to at least allude to it, since just Doppler redshift observations seems like not such a sturdy foundation, especially without anything else buttressing it!
You're suggesting either an interaction with something unknown, which I'm extremely skeptical about because there aren't any known interactions of light with particles that would simply shift it's frequency, and those particles would have to be visible because they do interact with light. So an impossible interaction.
Or you're suggesting a violation of conservation of energy and momentum of light over large distances, by vacuum itself. Which would probably be detectable here. Not even sure how you can suggest it in a consistent way.
Then there's the reasonable option, that it's just gravity and the spacetime metric itself changing, which is the leading theory anyways. Explaining it away with some invisible matter that acts only gravitationally, like you suggested, is literally what they are doing.
I'll be up front about this. I'm in way over my head in this discussion, but in my mind, still, not all interactions are with particles. There are fields such as gravity, that affect wavelength.
And what about particles we do see? What if the debris we know is out there (the stuff of collisions and non-congealed leftover particulates, early gases since its many light years away) over immense distances have an accumulative affect? We see the red sunset but do not discern any individual particles with our eyes.
Then there are the things we don't see. Dark matter... and so much of it. I'm guessing that disproving the relevance of all of this has proven tedious, and recounting it to a newbie like myself even more tiresome!
> "Professor Carroll, ... has reasons for his faith in the expanding universe theory, “evidence” which he gives here."
Does anyone know where this list of 4 or 5 evidences that the universe is expanding are that Sean Carroll outlines? I had the link but am not finding it!!
Your argument is not that effective for any who do not see evidence of a big bang. Steady state seems unlikely, perhaps a crude starting point, but it was closer to a model of the universe with sources and sinks, which are abundant and are everywhere.
Clearly Einstein missed his opportunity to lead the way in devising a theory of quantum mechanics, he was using his intuition and his method of thought experiment, and did not progress our understanding there. But when it comes to larger, more stable phenomena, I'm not so sure his intuition was so far off
What part is incorrect? That there is a desire and need for an observable beginning? That I said it "might", in other words, could potentially have come into play? I don't think you know that this has not happened. How can you possibly know? You are entitled to believe what you like, but use the word "incorrect" when you know something is false. Something is not necessarily false just because it contradicts your beliefs!
> That there is a desire and need for an observable beginning?
Yes. That part. Hinduism doesn't have it. And again: Einstein explicitly added a constant term to an equation to make it so that his theory did NOT imply a beginning. He wasn't Hindu mind you. He was Jewish!
> You are entitled to believe what you like, but use the word "incorrect" when you know something is false
That seems a bit much honestly. It's like Christians saying "you don't KNOW there is no God!!!". But yea.. I do. I also know the fact about Einstein above.
Just because SOME people want to show there is a start of time, doesn't mean it's the prevailing scientific theory for that reason. In fact, again like I said above, we know this isn't so as a historical fact.
I'm not putting forth any "conspiracy theory". You should know that human preference can cause people to act individually and independently in ways that conform to that preference. This is not conspiracy, it is confirmation bias. Groupthink may be at play, but this is also different from conspiracy because there is not necessarily any deliberate plotting to control going on necessarily. So with all the gradations of stuff in between extremes, you've not only placed me in an extreme, you've chosen the wrong extreme.
Sure. But your stated idea of what the group think is, is counter to what it was historically. Einstein screwed up his most significant life work to conform to the OPPOSITE of what you think is the group think.
I've been a part of a subculture that lied to me, something not related to physics or STEM, but after years of drinking the koolaid I finally learned the emptiness of what the community of 'experts' were saying and what so many followers were swallowing whole. This experience damaged my ability to just believe experts. It has affected me in such a way that I don't just give people a license to do handwaving indefinitely. I've come to realize that my intuition could've freed me earlier on from the falsehood that an entire population was swallowing. This time around, I went with my gut. This time I want to know if there is coercion at play (calling people "crackpots" and shaming) or if there is evidence that needs to be laid out.
There's definitely need of more scientists and not of more experts. Experts means "with experience", which might be of greater quantity or quality than average, but that doesn't cut it. Experts is also where charlatans and quacks abund, because we don't usually keep their opinions and work against the same bar as we do with scientists and scientific publications.
This explains why there is no "epicenter to speak of", but why is that expansion faster than the speed of light? How could it be? And is the evidence for that expansion really that solid?
I find this to be the crux of the issue. To be exempt from the rules that material things must follow, you simply need to designate it as space.
If space is what fills an area between object A and object B and that space grows or expands. This is no different than object A moving away from object B. What's the difference? There seems to be none.
After seeing more results and news coming from the JWST, it felt like time to pull the trigger on this article. I probably should've dug into Professor Sean Carol's list of evidence for the prevailing interpretation of redshift coming from distant objects. I may be eating crow for this neglect. Wouldn't be the first time.
That would be much appreciated. I'm interested in learning even if it takes me away from things that seem intuitive. So as I've mentioned in my article, light from more distant objects could be shifted red, not by a dopplar effect, but by its interaction with space debris or just propagation itself over extremely long distances. Where the expanding universe theory seems to "go wrong" is by violating the cosmic speed limit.
Ok, that's a "tired light" theory. It fails because that process just changes the frequency of photons, but not their density in space. The background radiation is (to extreme accuracy) blackbody radiation. Blackbody radiation has a spectrum, and an intensity, dictated by physics. The expansion of space preserves both aspects of "black bodiness"; tired light does not.
Tired light also doesn't explain the observed stretching in time of supernova light curves with distance.
> that process just changes the frequency of photons, but not their density in space.
Frequency is precisely the necessary thing that needs to be considered as an observed phenomenon that can have alternative explanations, since frequency relates to shifting toward red.
Are you saying that density/luminosity is an independent way of corroborating universal expansion? I don't believe that's the case.
Neither luminosity nor redshift seem, IMHO, to be strong enough evidence to uphold a "preposterous" (to use Sean Carroll's favorite descriptive term for the world) theory that massive things are not just traveling but accelerating away from oneanother.
I'm saying that tired light makes an incorrect prediction: that (absent some incredible coincidence) the CMBR will not have the density of blackbody radiation at the same spectral temperature.
It also falsely predicts that SN light curves are not stretched out at higher red shift.
Theories that make incorrect predictions are dead theories. We know for sure they are wrong.
This has nothing to do with the Big Bang, btw. Science works by killing theories, and tired light has been slain. It would be ruled out even if there wasn't an alternative theory available.
I don't doubt that the "tired light" theory has been slain. I can update my orientation from your informed response without hesitation. However, I don't think I'm truly talking about the "tired light" theory in a way that plugs into your understanding of it. Although I mention debris in the article, and then kind of took it off the table, what I still have left to posit is that light propagation looses energy over billions of light years, not some short distances that can be tested in a lab or verified via other corroborating observations that relate to shorter distances or parallax geometry. I've completely placed my theory and conjecture out of reach of the lab! Or have I? If I have it might not be worth much in the community of experts, but it still means something to me because I feel like, and nobody seems to be responding to this in any detail, cosmic speed limits are being broken all over the place, as my article states.
Yes, you are talking about a tired light theory. You are talking about a theory that robs energy from photons (never mind there's no known physical way to do this that doesn't scatter them, which isn't seen) but does not also stretch out the time of other physical processes, and stretch out the space containing the photons.
What you are proposing is ruled out by the generic argument against all such tired light theories.
The expansion of space is entirely consistent with special relativity (the source of the "cosmic speed limit"). What relativity says is that the speed of light is consistent in all reference frames, which leads to all the phenomena you've heard about, such as time dilation, redshifting, and the upper bound on velocity. However, you have to understand that space and time are the same substance called "spacetime", and adding new space changes the basis of your velocity measurement (v = dx/dt). It's entirely possible that adding space between two regions can cause those regions to separate at a velocity faster than light in either reference frame, because space is the `dx` in the formula.
Another apparent violation of the speed limit occurs beyond the event horizon of a black hole. Space itself is drawn to the singularity faster than light.
I worded my reply poorly. I mean to say, Your notion or model of the universe is all downstream of assumptions that redshift can only be related to the Doppler effect (apparently there are a couple types of Doppler effect as the article mentions and links to info relating to "a normal Doppler redshift"). If everything rests on that assumption, it would be something to scrutinize if more and more observed astronomical data continues to pour in contradicting the big bang or expanding universe.
Separating "space itself" from the objects that are governed by universal laws is like saying there could be a north pole without a planet such as Earth. Take away Earth, you have no north pole. Take away objects in motion, you have no basis for talking about spacetime. That's just my intuition, but it seems to point to a gap in explanations, at least from science popularizers.
This is all downstream of assumptions that redshift is a certain kind of doppler effect. Redshift could actually be something other than that, and space from outta nowhere feels like just wishful thinking to me. And why is that space getting introduced without also bring with it its own time component? This seems to contradict your point that we don't just deal with space, but spacetime!
