The first model of cosmology that I was exposed to, as a small child, was that of the static universe, because that's all my father knew. According to that model, the universe is infinite in all directions, it is eternal, and it is not going anywhere. Of course I accepted it, because that is what kids do: accept everything presented to them as fact.
Then, during elementary school, I heard of the Big Bang and the expansion of the universe; this new model of cosmology made me feel a bit uncomfortable, but again I accepted it, because a) that's what the scientists said, and b) I could go to my father and tell him that he is wrong.
Later, during my junior high-school years, I heard of the red-shift of galaxies, as simply the Doppler effect applied to light, and it sounded reasonable, but then I heard of cosmological red-shift, as the stretching of photon wavelengths due to expansion of space itself. That sounded very exotic to me. I was again willing to accept it, because scientists had said so, but I was now starting to feel uncomfortable, because I am not into pretending to understand things that I do not truly understand. (Furthermore, my father had no concept of such things, so I could not even start a discussion with him with the goal of showing him that he is wrong.)
Then I started hearing of truly bizarre observations, such as that galaxies in all directions around us are red-shifted, meaning that they are all moving away from us. When I want to comically express my bewilderment at this, I raise my arms, smell my armpits, and say "why, what's wrong with us?"
I learned that according to red-shift observations, the farther away a galaxy is, the faster it is moving away from us, and that not only the galaxies are moving away from each other, but the rate at which they are moving is increasing, meaning that galaxies are accelerating away from each other. Again I accepted all that because scientists had said so, but by that time it was already clear to me that I was accepting these things only because I had no other option. A little something in me was finding all this uncomfortable to the point of being disturbing.
The apex of my discomfort came during my last year of senior high-school, when I started hearing of dark matter and dark energy; popular media portrayed them as discoveries, but a closer examination of what the scientists were actually saying revealed that they were nothing but fictitious notions that scientists had dreamt up in order to explain the observations, otherwise the numbers did not add up. In other words, the scientists had given names to their ignorance. And it was not just some small discrepancies that these novelties were called to correct for; dark matter and dark energy were supposed to account for about 95% of the universe. On the surface I was okay with this, because again, scientists had said so, but that little something in me had now started finding all this quite preposterous and becoming genuinely disturbed.
Stop for a moment and think how arrogant this is on our behalf: we are saying "here are our observations of the universe," and "here are our theories to explain those observations," and "by the way, our theories only explain 5% of the observations, the remaining 95% is inexplicable." And instead of admitting that our theories are worthless, we take it for granted that they are correct, and we assume that there must be some as of yet completely unknown and completely unobserved mechanisms at play which account for the missing 95%, so that our theories end up being correct. To top it all off, we come up with a couple of cool names for those mechanisms, to make the public think that we actually have a clue as to what we are talking about.1
This was so disturbing to me, that in order to retain my sanity I was forced to invest some thinking into it, despite the hopelessness of the endeavor, given that I have no formal background in physics, let alone astrophysics; my field is software engineering.
My thinking was, necessarily, simple:
There is no doubt that relative movement of galaxies in space is at least partially responsible for the observed red-shift, just as it is responsible for the few cases of observed blue-shift. For example the Andromeda galaxy is blue-shifted, because it is on a collision course with the milky way. However, this does not mean that relative movement is necessarily responsible for all of the observed red-shift. Can we find some additional means of explaining red-shift so that we might account for the truly bizarre manifestations of red-shift?
I tried to think what it means to say that the fabric of space is expanding. How do we know that it is expanding? Could it be that the only way that we know that it is expanding is due to the observed red-shift? If so, then how do we know that it is the fabric of space that is expanding, and not the frequency of the light that is dropping?
If light happens to have an as of yet unknown property which causes its frequency to ever so slightly decrease as it travels through the vast expanses of intergalactic space, then clearly, the result would appear as red-shift. That would beautifully explain at least two observations that are currently receiving disturbing explanations:
- Light reaching us from any galaxy has to travel a long distance, therefore all galaxies should appear red-shifted, as they indeed do, even though they might be more or less stationary with respect to us. This is a much nicer explanation than to say that all galaxies are running away from us as if we have smelly armpits.
- Light reaching us from distant galaxies has to travel a longer distance than from nearby galaxies, therefore more distant galaxies should appear more red-shifted, as they indeed do. This is a much nicer explanation than to say that galaxies are not only moving away from us, but actually accelerating away from us.
I knew that my idea had at least a tiny bit of merit due to Occam's razor: sure, I was postulating some as of yet unknown property of light that causes its frequency to decrease as it travels through space, but:
a) this is not a terribly implausible thing to suppose, and
b) it seems far less implausible than proposing an expanding universe, an expanding fabric of space, (let alone a fabric of space,) plus dark matter and dark energy to make the numbers add up.
Simply put, Occam's razor says that if two hypotheses have equal explaining power, the simpler one wins. What remained to be seen was whether my hypothesis did actually have equal explaining power as the established scientific theories. I suspected it did not, due to reasons beyond my level of comprehension of the universe, but I had no one to ask, and so no way of knowing.
I had this idea in my late teens, and not knowing what to do with it, I stored it in the back of my mind and went on with my life.
When I was at California State University, San Bernardino I had a cool professor who came to the classroom one day with an inflatable balloon that had galaxies printed on it. By inflating the balloon, she showed how the expansion of the fabric of space can explain the observation that all galaxies are seemingly moving away from us, as well as from each other; I could accept this, but it only took care of the smelly armpits problem; the highly exotic notion of an expanding fabric of space was still there, the troublesome acceleration of the expansion was also still there, and the preposterous notions of dark matter and dark energy were still there. So, I felt that my hypothesis had lost virtually none of its explanatory merit.
During the mid 2000s, in the golden era of internet blogs, and before facebook destroyed everything, I happened to have access to an audience of a few thousand people with higher than average education. A sizable portion of them were necessarily scientists, so a few of them were bound to be astrophysicists. This prompted me to describe my idea on my blog and ask if anyone had heard of anything similar to it. Sure enough, a couple of folks stepped up to inform me that my idea had already been considered by scientists, and that although not completely devoid of scientific merit, it was regarded as false, and it had pretty much been proven wrong by experimental observations. It even had a name: The Tired Light Hypothesis.
That was an elating moment for me; I was thinking that for a lay-person like me to independently arrive at a hypothesis which had also been considered by actual astrophysicists was a substantial accomplishment, even if the hypothesis did not turn out to be correct.
Of course it would have been even more elating if they had said "hey, wow, guess what, we never thought of this, and you know what? you might actually be right!" but let us be serious, what are the chances of that happening?
I am weary of the phenomenon of fringe theories, where certain ideas seem to exert an irresistible appeal to non-scientists, causing misinformation to spread. I also happen to be somewhat partial to another fringe theory, which is the Aquatic Ape Hypothesis, and while delving in it I have witnessed the controversy: large numbers of non-biologists loving it, virtually every biologist wishing that the hypothesis would just die so that people would stop pestering them with it. When David Attenborough endorsed the hypothesis, the scientific community very nearly cancelled him. Even I, personally, thought that was kind of risky on behalf of David Attenborough to endorse the hypothesis, even though I kind of liked it. So, I am fully aware of the fact that these are fringe theories, and I am not insisting on anything, I am just expressing my amusement at how beautiful they are and how much explanatory power they have.
Also, it gives me a warm, fuzzy feeling to keep note, somewhere in the back of my mind, of the fact that another thing that was at some point regarded by the scientific community as nothing but a fringe theory was the Continental Drift Theory.
See Wikipedia: Static Universe
See Wikipedia: Big Bang
See Wikipedia: Expansion of the universe
See Wikipedia: Tired Light
See Wikipedia: Fringe Theory
1 And that's not even all; we are even saying that other than exerting gravitational pull, dark matter does not seem to interact with regular matter, not even with itself, so it is virtually unobservable. This inevitably brings to mind the powerful skeptic argument about the invisible, odorless, and untouchable realm of the supernatural as being virtually indistinguishable from the non-existent.
Cover image: "Tired Light" by michael.gr; incorporating starry background from ChatGPT and photon sphere from Perplexity; stretching sine wave created using Desmos.com.
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