Here’s an article from one of the most popular creationist web resource, Answers in Genesis: http://www.answersingenesis.org/articles/nab/does-starlight-prove. In this post, we shall be critically exploring the article, only to find that it’s essentially flawed.
Consider the following excerpt: “The argument goes something like this: (1) there are galaxies that are so far away, it would take light from their stars billions of years to get from there to here; (2) we can see these galaxies, so their starlight has already arrived here; and (3) the universe must be at least billions of years old—much older than the 6,000 or so years indicated in the Bible.”
That’s hardly the way we conclude that the universe is billions of years old. A prominent American astronomer, Edwin Hubble, proposed what we call the Hubble’s Law. It essentially states that the distance of a star is directly proportional to its relative velocity of recession, the constant of proportionality being the time dependent Hubble Constant. It’s a principle experimentally verified. This makes it very convenient to measure the distances/velocities to/of stars far off in the depths of the Cosmos. The process is infact backed by a couple of reliable techniques (interpretation of redshifts in the spectra of stars and the distance modulus, to be specific). That’s about the distance. The expansion of the cosmos is a direct consequence of FLRW Solutions to Einstein’s Field Equations, under the frames of the cosmological principle. It’s interesting to note that the Hubble’s constant lays correspondence to Friedmann’s equations, where it’s found to be time dependant; that is a parameter which varies with time. This simply implies that the current rate of expansion is NOT being extrapolated to past, as the site claims further down the article and the page: (http://www.answersingenesis.org/get-answers/features/billions-of-years). Moreover, experimental verifications explicitly testify the fact that the universe has been governed by the same laws since the very beginning.
So that’s the deal. We know the way at which our universe expands and had been expanding (from the Friedmann Equations) and how much the universe has already expanded. All we now do is wind time back and watch the show, which turns out about 13.7 billion years long. It’s somewhat like calculating the time taken by a car to travel a hundred kilometers if it hits an average of fifty kilometers a second. This might seem enough to counter the essence of the article.
Let’s now consider the assumptions, which the author believes, are flawed. First, the constant speed of light.
“It is usually assumed that the speed of light is constant with time.2 At today’s rate, it takes light (in a vacuum) about one year to cover a distance of 6 trillion miles. But has this always been so? If we incorrectly……”
Wait a minute. That’s a clearly against the most popular and verified principle in physics till date: the special relativity, which explicitly states the speed of light in vacuum, is, and always had been a universal constant. A positive response to this statement cannot be considered scientific in any sense.
Further down the article, the author says time has never been anything “rigid”. True, it never did. Every object in this universe has it’s personal measure of time. Every object, but light. Light travels at a constant speed (in vacuum), and it’s the space and time which, in a sense, “reconfigures” itself (which, I emphasize, is relative) to bout the velocity of the observer considered. It’s only the rate of flow of time which is determined by gravitational influence. Light will approach earth with same speed, no matter its (the earth’s) position in a gravitational well. That’s infact the essence of special and general relativity, and the reason why time actually runs slower in a gravitational field. The situation described by the author depicts one where light is apparently “slowed down” due to time dilation on planet earth. And as I’ve mentioned afore, light slowing down is a concept purely a non-scientific. Moreover, given that time is not rigid, how do we know if the universe is so claimed 6000 years old for an observer at deep space (under minimum gravitational influence), or for one inside what we call a “gravitational well”? Well, the best we can say is that he didn’t remember to mention.
In the next section, the author talks of something he calls “universal time”. This won’t take me many lines to counter, because Relativity strictly lays that there isn’t anything “universal”. Universal time exists in a reality where relativity does not hold well, which is certainly not the one we dwell in. Let’s just ignore this for a while:
“Imagine that a plane leaves a certain city at 4:00 p.m. for a two-hour flight. However, when the plane lands, the time is still 4:00. Since the plane arrived at the same time it left, we might call this an instantaneous trip. How is this possible? The answer has to do with time zones. If the plane left Kentucky at 4:00 p.m. local time, it would arrive in Colorado at 4:00 p.m. local time. Of course, an observer on the plane would experience two hours of travel. So, the trip takes two hours as measured by universal time. However, as long as the plane is traveling west (and providing it travels fast enough), it will always naturally arrive at the same time it left as measured in local time.
There is a cosmic equivalent to local and universal time. Light traveling toward earth is like the plane traveling west; it always remains at the same cosmic local time. Although most astronomers today primarily use cosmic universal time (in which it takes light 100 years to travel 100 light-years), historically cosmic local time has been the standard. And so it may be that the Bible also uses cosmic local time when reporting events.”
First things first: for such a balance to exist, the aircraft must as travel just as fast. Let it travel a little faster, it’ll arrive Colorado before 4:00 pm local time. A little slower, it’ll arrive after 4:00. If it is to arrive at Colorado at 4:10 pm, there’s a fixed velocity it has to travel with. Same applies to a case where it is to arrive at Colorado by 3:50 pm. Its velocity must exactly be synchronized with that of earth’s rotation. If it is to anyhow happen that way with the universe, how do we bet that light travels with exactly the right speed, so it arrives at earth just as predicted by the Bible? What if I wrote something like the Bible, claimed that the universe is, let’s say 10,000 years old, and explain it by saying I meant it in the “cosmological local time”? Easy as it seems. Moreover, the author attacks his own thesis: the universe is 6000 years old in what’s supposed to be the “universal” time (well, I could at least suggest a more plausible term: proper time); the cosmological local time is purely relative, and evolves under the frames set by relativity.
The next section finds Naturalism under attack. “Naturalism is the belief that nature is all that there is.” The statement is self defending. Opponents of naturalism claim that it’s “blind faith”. In other words, they try to say that there’s something outside of nature. But that’s the deal: if there’s something outside of nature, we’re perhaps mistaken about the outside we mention: everything which is “outside” nature as we initially thought must be inside it. In other words, there’s no “outside” to nature: it’s all that exists. It’s where most authors end up saying “It’s God, and that’s about it”. It’s just one of the many things which make them sound ignorant.
The last section poses the so called “horizon problem”, which is explained by the cosmic inflation. The horizon problem is hence a live evidence for the cosmic inflation. How? Consider the analogy presented below. A deflated balloon may have a considerable amount of bass and relief. So we call it heterogeneous; a fair deal at this point. Now, inflate the balloon and watch the bass and relief vanish! It becomes smooth, which in this analogy, corresponds to a homogeneous distribution of matter. The Cosmic Inflation brought about a homogeneity in the cosmos at a rather large scale, which very well agrees with experiment. So much for the big “horizon problem”.
To conclude, I’d count on a universe explained by concrete mathematics and logic, instead of the one put forth by ancient manuscripts, laid upon someone who in my opinion, is a weak, fallen myth.
That's it from me now. Chimo!
