# red shift and the not expanding universe **URL:** \ **Category:** Factual Questions\ **Created:** [September 13, 2017, 3:28am UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204 "2017-09-13T03:28:31Z")\ **Posts on this page:** 20\ **Page:** 3
**Author:** ![K364](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/k364/32/5_2.png) [@K364](https://boards.straightdope.com/u/K364)\ **Post date:** [September 14, 2017, 7:35pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/41 "2017-09-14T19:35:11Z")
In the vicinity of the Earth, the Sun’s gravitational field is the third most powerful. By far, the Earth’s is the most powerful followed by the Moon. ---
**Author:** ![Darren\_Garrison](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/darren_garrison/32/92_2.png) [@Darren\_Garrison](https://boards.straightdope.com/u/Darren_Garrison)\ **Post date:** [September 14, 2017, 8:04pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/42 "2017-09-14T20:04:17Z")
> [@Exapno\_Mapcase](#): > > Light and all other electromagnetic radiation is composed of p_ **h** _otons. Where are you getting p_ **r** _otons from? Look at the first post in [his first thread here](http://boards.straightdope.com/sdmb/showthread.php?t=823779). He thinks that a proton is a neutron that has absorbed a photon. ---
**Author:** ![MANTRAPHILTER](https://avatars.discourse-cdn.com/v4/letter/m/ecd19e/32.png) [@MANTRAPHILTER](https://boards.straightdope.com/u/MANTRAPHILTER)\ **Post date:** [September 14, 2017, 8:35pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/43 "2017-09-14T20:35:11Z")
> [@Lemur866](#): > > Except there’s no abrupt boundary to the gravitational field, it’s a smooth curve and varies by well known physics explained by Newton. > > You are correct that light can be red-shifted or blue-shifted to various observers based on their particular position within a gravity field. But as has been explained to you, the amount the sun will redshift photons is very small compared to the redshift we see from very distant galaxies. > > And you still haven’t acknowledged that the redshift we see in distant objects is proportional to their distance, which was discovered famously by Hubble: [Hubble's law - Wikipedia](https://en.wikipedia.org/wiki/Hubble%27s_law) > > If redshift was caused only by the sun, then light from every source outside the solar system would be shifted the same amount. And in fact it is, as was explained. But this redshift is very small compared to the actually observed redshift we see from distant sources. > > The only explanation of Hubble’s Law that makes sense is if these distant objects are moving away from us, and the simplest physical explanation of that is that the universe is expanding. You could explain it in other ways–the universe could stay the same size but everything in the universe is shrinking, for example. But that’s a funny explanation, and it makes more sense to just say that the universe is expanding. 1-I never said I think red shift is only caused by the suns gravity field. 2- distant galaxies that show redshift means that they are moving away from us. If you believe that it means the universe is expanding, that is your belief, (religion), NOT a proven fact. I am not saying that the universe is not expanding, just that I am not completely convinced by the evidence. ---
**Author:** ![dtilque](https://avatars.discourse-cdn.com/v4/letter/d/d6d6ee/32.png) [@dtilque](https://boards.straightdope.com/u/dtilque)\ **Post date:** [September 14, 2017, 8:39pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/44 "2017-09-14T20:39:06Z")
> [@MANTRAPHILTER](#): > > You have an understanding of my theory but, you have it backwards. No I don’t have an understanding of your “theory”, neither foward nor backwards. What I said was what GR says. If your theory counterdicts GR on this, it’s likely total bunk. If your “theory” says that light coming into the solar system is heavily redshifted, then how do you account for the fact that half of all stars are blueshifted? ---
**Author:** ![MANTRAPHILTER](https://avatars.discourse-cdn.com/v4/letter/m/ecd19e/32.png) [@MANTRAPHILTER](https://boards.straightdope.com/u/MANTRAPHILTER)\ **Post date:** [September 14, 2017, 8:41pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/45 "2017-09-14T20:41:42Z")
> [@K364](#): > > In the vicinity of the Earth, the Sun’s gravitational field is the third most powerful. By far, the Earth’s is the most powerful followed by the Moon. exactly! all of the masses are held in place by each others gravitational field, So, how does this disprove my theory? ---
**Author:** ![Dallas\_Jones](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/dallas_jones/32/3277_2.png) [@Dallas\_Jones](https://boards.straightdope.com/u/Dallas_Jones)\ **Post date:** [September 14, 2017, 8:46pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/46 "2017-09-14T20:46:52Z")
You are my density. ---
**Author:** ![Lemur866](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lemur866/32/434_2.png) [@Lemur866](https://boards.straightdope.com/u/Lemur866)\ **Post date:** [September 14, 2017, 8:50pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/47 "2017-09-14T20:50:57Z")
So, your theory is that distant galaxies are moving away from us, but the universe itself isn’t expanding. OK. What does that have to do with red shift? Your first post was about how maybe the apparent red-shift is really caused by the gravity of the sun, and that maybe if we observed stars in the direction of the sun (during an eclipse) rather than away from the sun (like at night) we wouldn’t see a red shift. Except it turns out not to be the case. We see a red-shift for all distant objects, no matter where they are in the sky in relation to the sun. And we observe a wavelength shift due to the sun’s gravity, but it is very small compared to the shift we see in distant galaxies. All distant galaxies are red-shifted, which can only be explained if all those galaxies are moving away from us. And since the more distant a galaxy is, the greater the red shift the only explanation is that everything is moving away from everything else. That means an expanding universe. Or do you deny Hubble’s observations? It seems like you don’t, right? But the problem is that you don’t have an alternative explanation except, “maybe it’s wrong”. ---
**Author:** ![MANTRAPHILTER](https://avatars.discourse-cdn.com/v4/letter/m/ecd19e/32.png) [@MANTRAPHILTER](https://boards.straightdope.com/u/MANTRAPHILTER)\ **Post date:** [September 14, 2017, 8:59pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/48 "2017-09-14T20:59:45Z")
> [@dtilque](#): > > No I don’t have an understanding of your “theory”, neither foward nor backwards. What I said was what GR says. If your theory counterdicts GR on this, it’s likely total bunk. > > If your “theory” says that light coming into the solar system is heavily redshifted, then how do you account for the fact that half of all stars are blueshifted? I do not recall saying heavily redshifted. A shift in the spectrum can occur without moving it into the red. It sounds to me like you are repeating things you have learned. Memorizing is a form of knowledge. but I am not sure if you really understand the concept of GR. I do not mean this as an insult, although you will probably take it that way. If distant galaxies show red shift and it means that the universe is expanding. Then by the same reasoning. the local stars that show blue shift means that our galaxy is imploding. ohhh nooo. ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [September 14, 2017, 9:07pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/49 "2017-09-14T21:07:58Z")
> [@MANTRAPHILTER](#): > > If distant galaxies show red shift and it means that the universe is expanding. Then by the same reasoning. the local stars that show blue shift means that our galaxy is imploding. ohhh nooo. Local stars are in orbit around the center of our galaxy like the Sun. What was said was that some nearby galaxies were blue shifted. And my understanding is that they will collide with our galaxy in a few billion years or so. Are you aware that the red shift is not constant, but increases with distance, just as predicted by an expanding universe? ---
**Author:** ![Lemur866](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/lemur866/32/434_2.png) [@Lemur866](https://boards.straightdope.com/u/Lemur866)\ **Post date:** [September 14, 2017, 9:17pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/50 "2017-09-14T21:17:51Z")
“Red-shifted” of course does not mean literally shifted into the portion of the visible light spectrum we hu-mons call “red”. It just means shifted toward a longer wavelength, the same as blue-shifted just means shifted toward a shorter wavelength. A gamma ray can be red-shifted to the x-ray band of the spectrum, or a radio wave can be blue-shifted to a microwave, or a blue visible light photon can be red-shifted to yellow. The thing about our local galaxy is that when we look at all the local stars some are moving towards the sun and are blue-shifted, and some are moving away and are red-shifted and some aren’t moving much at all relative to us. So there’s no trend of contraction of expansion of our galaxy. And the same is true for near galaxies, as was stated Andromeda is moving towards us and we’ll eventually merge with it billions of years in the future. So in our galaxy everything is just orbiting around the center, some stars get closer or farther because each star is in its own individual orbit. And our local cluster of galaxies is also gravitationally bound to each other. It’s only the distant galaxies that are all moving away from us, and the farther away they are the faster they are moving away from us, in a very regular relationship known as the Hubble constant. > **[Hubble's law | Determining the Hubble constant](https://en.wikipedia.org/wiki/Hubble%27s_law#Determining_the_Hubble_constant)** > > The value of the Hubble constant is estimated by measuring the redshift of distant galaxies and then determining the distances to them by some other method than Hubble's law. This approach forms part of the cosmic distance ladder for measuring distances to extragalactic objects. Uncertainties in the physical assumptions used to determine these distances have caused varying estimates of the Hubble constant. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [September 14, 2017, 10:08pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/51 "2017-09-14T22:08:44Z")
> [@MANTRAPHILTER](#): > > If distant galaxies show red shift and it means that the universe is expanding. Then by the same reasoning. the local stars that show blue shift means that our galaxy is imploding. ohhh nooo. This makes as much sense as saying that because a pump moves water into your upstairs toilet, the notion that water flows downhill to sea level is therefore wrong. ---
**Author:** ![MANTRAPHILTER](https://avatars.discourse-cdn.com/v4/letter/m/ecd19e/32.png) [@MANTRAPHILTER](https://boards.straightdope.com/u/MANTRAPHILTER)\ **Post date:** [September 14, 2017, 11:16pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/52 "2017-09-14T23:16:39Z")
> [@Voyager](#): > > Local stars are in orbit around the center of our galaxy like the Sun. What was said was that some nearby galaxies were blue shifted. And my understanding is that they will collide with our galaxy in a few billion years or so. > > Are you aware that the red shift is not constant, but increases with distance, just as predicted by an expanding universe? I am aware of that, but how do you know that the red shift in the distant galaxies definitely means that our universe is expanding? Could there not be another explanation? Maybe something else is happening to the light spectrum as it travels over a long distance that we just haven’t figured out yet. Just accepting that the universe is expanding, is like closing your thought process and not allowing any other idea for an explanation to be explored and is closer to the blind faith of most religions. ---
**Author:** ![MANTRAPHILTER](https://avatars.discourse-cdn.com/v4/letter/m/ecd19e/32.png) [@MANTRAPHILTER](https://boards.straightdope.com/u/MANTRAPHILTER)\ **Post date:** [September 15, 2017, 12:18am UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/53 "2017-09-15T00:18:05Z")
When a wave encounters a buoy in the ocean, some of the waves energy is absorbed by the buoy, but the wave continues on. A wave of light in three dimensions has also encountered many different buoys as it travels. The longer the distance, the more buoys. Is the wave length effected by its encounters? I do not have all the answers, but, I want to be able to ask the question, and not just accept the answer that is popular for fear of being an outcast. ---
**Author:** ![Voyager](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/voyager/32/133_2.png) [@Voyager](https://boards.straightdope.com/u/Voyager)\ **Post date:** [September 15, 2017, 1:46am UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/54 "2017-09-15T01:46:01Z")
> [@MANTRAPHILTER](#): > > I am aware of that, but how do you know that the red shift in the distant galaxies definitely means that our universe is expanding? Could there not be another explanation? Maybe something else is happening to the light spectrum as it travels over a long distance that we just haven’t figured out yet. Just accepting that the universe is expanding, is like closing your thought process and not allowing any other idea for an explanation to be explored and is closer to the blind faith of most religions. The increased red shift means that things more distance are receding faster, which is pretty much the definition of the universe expanding. Plus, object with huge redshifts like quasars are more primitive than what we see locally, which is reasonable since we are seeing their light from 10 billion years ago or more. You are free to come up with a hypothesis giving another reason for the red shift observed, but it should be testable. Until then the expanding universe is the best explanation so far, which is why it is provisionally accepted. Plus we have to mention that another effect of an expanding universe is that in the past it was very small. That resulted in predictions of the cosmic microwave background radiation - and when that was found, and matched the predictions, the Big Bang and the expansion were supported. If you think this is all a matter of blind faith, you have no clue about how science works. The reason there are few if any steady staters around is evidence, not the result of a holy war. ---
**Author:** ![Exapno\_Mapcase](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/exapno_mapcase/32/1051_2.png) [@Exapno\_Mapcase](https://boards.straightdope.com/u/Exapno_Mapcase)\ **Post date:** [September 15, 2017, 1:48am UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/55 "2017-09-15T01:48:54Z")
> [@MANTRAPHILTER](#): > > I am aware of that, but how do you know that the red shift in the distant galaxies definitely means that our universe is expanding? Could there not be another explanation? Maybe something else is happening to the light spectrum as it travels over a long distance that we just haven’t figured out yet. Just accepting that the universe is expanding, is like closing your thought process and not allowing any other idea for an explanation to be explored and is closer to the blind faith of most religions. Actual physicists have proposed dozens, if not hundreds, of alternative explanations. Other actual physicists have examined the possibilities and decided that they were wrong, or did not account for other phenomena, or did not make predictions which worked out, or in some other way failed to live up to the strict standards of modern science. Your implication that all the physicists in the world over decades of time simply accept a hypothesis blindly without testing it and evaluating all the other plausible possibilities is insulting to actual working physicists. It is true that they tend to immediately reject implausible alternatives that have no connection with reality. If your alternatives are being rejected that way, well, do the math, so to speak. ---
**Author:** ![Riemann](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/riemann/32/3133_2.png) [@Riemann](https://boards.straightdope.com/u/Riemann)\ **Post date:** [September 15, 2017, 5:31am UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/56 "2017-09-15T05:31:47Z")
> [@Exapno\_Mapcase](#): > > Actual physicists have proposed dozens, if not hundreds, of alternative explanations… And it’s not as though the Big Bang and the metric expansion of space is an _obvious_ notion for a human living on the surface of the earth, staring up into the night sky! The fact that the model is _still_ so widely misunderstood by the public shows what a bizarre and counterintuitive idea it really is. To accuse the great scientists who developed this model of lacking the imagination to consider other ideas is preposterous. The reason that this astonishing model prevailed is because it’s the only one that fits all the evidence. A starting point of not _understanding_ the evidentiary support for a current theory _never_ leads to overturning it with wild new ideas. It makes you an ignorant crank, nothing more. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [September 15, 2017, 6:44am UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/57 "2017-09-15T06:44:32Z")
> [@MANTRAPHILTER](#): > > My theory predicts that the wave length should expand as it approaches the mass of the sun, the compress as it moves away from the sun. problem is - we only observe it as it approaches the sun, due to our position relative in the suns gravitational field. I looked on the web to find out if red shift has ever been measured during the solar eclipse and could only find articles concerned with defining positions of stars concerning proving Einstein’s theory. If your hypothesis were correct, we would see something different when we look away from the sun perpendicular to the plane of the ecliptic vs various directions parallel with it. We are not in the same place as the sun, therefore we can look at stars when the sun is directly behind us, and later in the season, look at the same stars when the sun is to the side of us - and in those two cases, the starlight reaching us is travelling a different length through the Sun’s sphere of influence (in fact, this is the same experiment you propose to do with an eclipse, only using a different set of angles of observation. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [September 15, 2017, 6:47am UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/58 "2017-09-15T06:47:15Z")
> [@MANTRAPHILTER](#): > > I am aware of that, but how do you know that the red shift in the distant galaxies definitely means that our universe is expanding? Could there not be another explanation? Maybe something else is happening to the light spectrum as it travels over a long distance that we just haven’t figured out yet. Just accepting that the universe is expanding, is like closing your thought process and not allowing any other idea for an explanation to be explored and is closer to the blind faith of most religions. Nobody is dismissing ideas out of hand. They are dismissing ideas that are measurably false. In order to overturn the established view, you don’t just need to persuade people to open their hearts to your idea. You need an idea that works. ---
**Author:** ![Channing\_Idaho\_Banks](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/channing_idaho_banks/32/250_2.png) [@Channing\_Idaho\_Banks](https://boards.straightdope.com/u/Channing_Idaho_Banks)\ **Post date:** [September 15, 2017, 8:41am UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/59 "2017-09-15T08:41:27Z")
> [@Riemann](#): > > A starting point of not _understanding_ the evidentiary support for a current theory _never_ leads to overturning it with wild new ideas. It makes you an **ignorant crank,** nothing more. someone needs a special subtitle. ---
**Author:** ![Mangetout](https://sea3.discourse-cdn.com/straightdope/user_avatar/boards.straightdope.com/mangetout/32/19_2.png) [@Mangetout](https://boards.straightdope.com/u/Mangetout)\ **Post date:** [September 15, 2017, 12:51pm UTC](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204/60 "2017-09-15T12:51:54Z")
> [@MANTRAPHILTER](#): > > When a wave encounters a buoy in the ocean, some of the waves energy is absorbed by the buoy, but the wave continues on. A wave of light in three dimensions has also encountered many different buoys as it travels. The longer the distance, the more buoys. Is the wave length effected by its encounters? I do not have all the answers, but, I want to be able to ask the question, and not just accept the answer that is popular for fear of being an outcast. There’s nothing wrong with asking questions, but you’re missing an important point: the popular answer is only popular because _it works_ [Previous page](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204.md?page=2) [Next page](https://boards.straightdope.com/t/red-shift-and-the-not-expanding-universe/796204.md?page=4)