xxdeadmnwalkinxx responds to me...I think...he doesn't say:
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personally I can't conclude carbon dating as pure fact because it can't be tested empirically since we as a race have not been alive that long.
No, but the trees have. And the ice cores have been around that long. And so have the varves.
You see, there's a method of dating called "dendrochronology." That's where you count tree rings. A tree makes a ring every year that it's alive. By matching up tree rings from various specimens, you can determine when the tree was alive.
We have been able to get a continual dendrochronology going back over 10,000 years.
This makes it perfect to verify carbon-14 dating since it's only accurate for about 50,000 years. You can take a piece of wood which, through dendrochronology, you can make a direct calculation of its age by comparing it to the tree ring database. You then do a carbon-14 radiometric dating of it and see what it says.
You find that the two are in general agreement.
Thus, we have just empirically confirmed that carbon-14 dating is accurate.
By the way, you do understand that carbon-14 dating is only useful for biological material such as wood, leather, and the like, yes? You would never carbon-date a rock. Carbon-14 dating works as follows: A living organism is continually cycling carbon through the system. There is a fairly constant ratio of normal carbon-12 to radioactive carbon-14 in the environment and thus, while the organism is still living, the organism will have a similar ratio of C12 to C14 in its system. But when the organism dies, it no longer cycles carbon through its system anymore. The C14 starts to decay. By measuring the amount of C14 in the system now, we can come up with a fairly accurate determination of when the organism died. And given the life of C14 and the sensitivity of our equipment, we can't make a determination beyond a few tens of thousands of years. Thus, you would carbon date, say, the Shroud of Turin or the wooden sarchophagus of an Egyptian mummy since we know that these things aren't that old and they're made of organic material.
Again, you would never use this on a rock. Rocks don't cycle carbon through their systems. And since rocks are commonly much, much older than carbon-14 dating can accurately detect, it is a useless measurement. It would be like trying to use a 3-foot tape measure to try and measure the size of the galaxy except that every time you picked it up, it snapped shut and you lost your place for where you started.
Instead for things like rocks, we use other radio-isotopes like thorium-232 and beryllium-10.
You seem to be inching toward a claim that if we weren't there to directly observe it, then we know absolutely nothing about it. If so, then you're going to have to dump the entire field of forensics and throw open the gates of the prisons since most crimes don't have witnesses. And yet, we're able to determine what happened precisely because of what was left behind.
You're right that no human was around 100 million years ago when the dinosaurs were walking around. But the dinosaurs were there and their bones have managed to survive to the present day. By examining the objects that were there at the time, we can discover some things about what went on at the time.
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theories can still have the option of being debunked, if it was totally unrefutable, it would be a law. yes there are facts other wise it would never have become a theory in the first place. i.e. continental drift theory vs plate tectonics
As I'll say below, theories do not become laws. The top of the food chain in science is the theory.
However, you do understand that plate tectonics is the mechanism of continental drift and thus there is no "vs." to be had, yes?
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no offense and not to sound ignorant, but they are teaching gravity as a law in school.
That's because Newton coined it as a law. You see, during the Enlightenment when the clockwork universe was the reigning paradigm, everything was called a "law"...especially if it could be pithily described and even more so if it could be done so mathematically.
The problem is, Newton was wrong. That "law" of his is turning out to be not as accurate as we thought. The Pioneer space probes are leaving the solar system at a rate that is inconsistent with what we know about how gravity works.
In short, a "law" is just a mathematical part of a theory and is just as subject to change as new data comes along as anything else.
Take, for example, Newton's "laws" of motion. According to these laws, F = ma. The result of this is that motion is linear: If I am moving on a train going at 100 miles an hour and throw a ball such that it leaves my hand as 100 miles an hour, then it's speed is actually 200 mph. And if it approaches an oncoming train that is moving at 100 mph, it strikes it as if it were moving at 300 mph.
But we know that not to be true. Motion is not linear, it's relative. And there is an upper limit on speed: The speed of light. Instead of F = ma, it's actually F = dp/dt. Now, in a linear universe, dp/dt reduces to ma, but as stated previously, the universe isn't linear. It's relative.
So why do we still call it Newton's Second "Law" of Motion even though we know it's wrong? Because that's what Newton called it, the phrase stuck, and there's little point in harping on the point since all scientists know that it's just a part of the theory of kinematics.
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as for blue eyes, from my understanding it was a gene already included in the genetic make-up that is more recessive than brown eyes and more dominant than green or hazel.
Nope. Technically, there is no "gene" for green eyes. Instead, it is the interplay of pigments on the front and back surfaces of the iris that result in what we call "green" or "hazel" eyes. If you have the brown allele, you get brown eyes. Blue, however, gets all wonky. If you have no pigment on either side, you get blue. If you have some on one side but not the other, it is between blue and brown, thus "green" or "hazel."
And what do you mean "already included in the genetic makeup"? It's a mutated gene. Same with blood type. There is the allele for A, the allele for B, and the broken allele which, if you have two, results in O. They're all mutations.
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i know this off the topic, but how do you measure time?
There is a standard for time, you know. The SI system defines the "second" as "the duration of 9,192,631,770 periods of the radiation corresponding to the transition between the two hyperfine levels of the ground state of the cesium 133 atom."
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so is there a constant that doesn't change so that we can measure time somehow other than a system of irreversible succession that never stops? something to compare it to?
Yes and no. As relativity shows, time varies according to the reference frame. However, within a single inertial reference frame, it is constant.
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Rrhain
WWJD? JWRTFM!
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