Articles that give insight into science

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Permalink Reply by Dr. Krishna Kumari Challa on January 30, 2014 at 9:10am

*We use our logic to make out and utilise various aspects of the reality in which we live.
* The absence of logic is called faith.
* Logic is self-axiomatic, but that is the only way we can imagine.
* Science is simply a collection of logical statements constructed out of the various observations which we make in our universe.
* As time proceeds, our observations get more deeper/refined. So the validity of the statements are always being tested with the new observations and with proper logic, some are accepted,some are rejected or modified.
* The Scientific Method" is THE ONLY LOGICALLY possible way to study reality.

Science is a process. No one can make all possible observations or gather all kinds of data in a single go. Theory is a statement that logically fits the available set of data. Accepted theory is the simplest of all the possible theories. So, NO , NEVER , Science will ever claim that it can understand the Nature for sure and for ever. It only provides an approximation, and this is the ONLY LOGICAL tool we have.

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The scientific method is a way to try to strip away as many biases fallacies and other failings of the human brain when making observations on phenomena.  Peer review and independent testing is one of the critical ways this is done is by having other scientists and teams try to recreate the results of the original study.  If we find that many teams can recreate the results of the original study, then we know that odds are it is valid.  Lone, unverified studies and experiments should be viewed with skepticism at best.

This is how science is self-correcting.  You publish a study, your results aren't taken seriously until many others have reviewed your methodology results and conclusions and also can recreate the results in their own tests.

For example, if a well known vitamin supplement advocate publishes a story about how vitamin C cures cancer, you would probably be well to be leery.   If researchers around the world are able to independently show similar results, then you can probably start gorging on Flintstones vitamins.

With a little bit of science literacy and math, anyone can read published studies and review them critically.  Even if you aren't well educated in a specific subject, you can still look for possible methodology errors, funny math, biases, etc.  You don't HAVE to take someone's word for it if you don't want to.

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There are no scientific laws, just theories. They often get invented (discovered!) somewhat like this:

You look at something for a long time - let's say how waves move on the surface of a lake - and after a long time of jotting down data (wave height, wavelength, speed of the waves, temperature, wind speed, etc..) you notice there's s correlation between several of these factors. So you formulate a theory: "When there's more wind, the waves are higher."

So... When the wind force is up, the waves are higher, but particularly so when the wind comes from a certain direction. Your theory doesn't hold equally well for every direction the wind comes from. In an attempt to explain these differences, you start to look for a reason why the force of the wind has a larger influence when coming from this particular direction.

You find out that the lake is deeper in that specific direction. So you'll now go and investigate spots with different depths, while keeping the windspeed constant (this takes a long time, because the weather is controlled by nature). After a few years of jotting down data again, you see a correlation between lake depth and wave height under a constant wind pressure. So you can formulate a new theory: "When there's more wind, the waves are higher. But the factor by which the waves are higher depends on the depth of the lake when measured one mile off shore. This factor is 1.2."

Now you're quite happy with your theory, so you publish it. But someone who's read it calls you - he's living close to a lake as well - and he tells you your theory doesn't seem to be true at the shore of his lake: the waves at his lake are much higher than your model predicts. So naturally you go there, eagerly, to find out what's going on. After all: at the lake where you're living your model has proven to be quite reliable and several boats of fisherman have been saved the past 5 years because of your accurate predictions.

Arriving at the lake of your critic, self assuredly, ready for a debate, you discover that his lake is much larger that yours. Both in surface and volume. Wow. It's instantly clear to you that your model for predicting wave height will fail. This is something you never thought about, but what to do? More data samples, measuring, correlating, etc.. There's another twenty years of work ahead. But you really want to know what's going on with lakes, wind and waves because it can help fisherman and other sailors. So you start taking measurements again.

This is basically how science works.
Many iterations of a proces just like this are the reason you can write a response on quora, using your iPad, PC, Mac, whatever. A little machine containing a processor with about a billion transistors calculating at 3 billion ticks per second. Technology we can only make because we know our scientific theories and models work and we know within which boundaries they do and don't.

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anyone -including you- can try to disprove them with any means necessary.

Actually, scientists are encouraged to do so. And when they succeed, a better scientific "law" (also known as theory) is developed to explain what happened.

In fact, there are no "truths" in science. Only hypotheses that haven't been disproved -yet :)

So what are you waiting for? Go make yourself famous by disproving some theory.

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Science is trying to decipher how the world works based on a series of observable phenomena. When we think we might have an idea of how something works, we start by making a hypothesis or a guess. We can then run an experiment to test that hypothesis. Based on the results of that experiment, it will give us an idea of whether or not our hypothesis is consistent with observations. Again, common usage is not always the same as scientific usage and it is somewhat frowned upon to call something "correct" in science.

A scientific theory is a step up from a hypothesis. A theory in science is something that has been repeatedly confirmed through experiments (the common usage definition is more akin to a guess, which is why the definition of a scientific theory can confuse). Scientific theories usually attempt to explain a mechanism for how something works or identify the cause for a phenomenon. The theory of gravity is an example of this. We have been testing the theory of gravity for hundreds of years and it is the result of countless physics experiments (and our own observations every day). We are still working to explain the "why" of gravity and the mechanism, the recent experiments of the Large Hadron Collider (LHC) and the discovery of the Higgs boson are more verifications of this.

A scientific law is different from a theory and a hypothesis. It is based on observations alone and generally doesn't explain "why." Conservation of energy is based on our observations, but we generally don't explain exactly why that happens. Scientific laws apply under a specific set of conditions and we consider them consistent with what we observe. Laws can be "false" if taken outside that set of conditions, but sometimes we can still use them to make inferences outside those conditions.
There is no well-defined "law of nature" in the scientific community. Plywood doesn't fly by itself, but we can use scientific laws such as Bernoulli's principle to make it fly! Science is constantly changing theories and laws to fit with new discoveries and experiments. You're right that sometimes people try to come up with new "laws of everything" but they're generally not taken seriously unless they can back up their claims with something observable.

The scientific method is a way of thinking and you have probably used it elsewhere in your life without realizing it. You have an idea and you test it out. If it works: yay! If it doesn't work: you make a new guess. My job is in scientific research: I get paid to try to figure out just another little piece about how the world works. It might not seem like it from textbooks, but it's a very exciting and rewarding place. The work that scientific researchers do is the very edge of knowledge. We're trying to figure things out that no one has figured out before. We use the scientific method and our observations to make new hypotheses. Sometimes we're wrong too, but we do our best! You can test out some of the scientific laws in your textbooks with some fun home experiments.

Permalink Reply by Dr. Krishna Kumari Challa on January 30, 2014 at 9:23am

Just because scientific laws are never perfect, doesn't mean you shouldn't trust them! Paraphrasing Alan Sokal, if you don't believe the law of gravity, you're welcome to jump out the window of a tall building to see what happens. Every time you turn your car on in the morning, use your computer, or walk to work, you test a bunch of these laws, and they've never failed. They are extremely likely to be true in an overwhelming majority of cases to a great level of accuracy. We just can't be 100% sure that they are always exactly right.
There are no absolute truths that we can know of -- not only in science, but in general. This is because we cannot observe the whole world in perfect detail. No matter how cherished a certain belief is, it may turn out to be wrong. Perhaps a certain law of physics that you thought was true because you've never seen it broken before turns out to not hold in some cases (this is what happened with Newton's laws).
I will use the definition which I think would be accepted by most people, that "true" essentially means "highly likely" or "with high accuracy". You'd probably agree that the statement "the sun will rise tomorrow" is true, although it's certainly possible that it won't. So, scientific laws are probably not "true", they're just the best model we have so far. We believe them because we've never seen them be wrong before, within the tolerance of our measurements and within their range of applicability. The scientific method is a way to improve these laws. How do we know it works?

One way is by looking at history. Science did not bring about the computer, but it did bring, for example, Maxwell's equations and the theory of the Turing machine, which were instrumental in the whole series of developments that ultimately led to the building of the first computer. The discovery of the second law of thermodynamics by Sadi Carnot was an essential step to building the better engines that made cars and airplanes possible, although it didn't directly create them. Taken literally, science didn't create the smartphone in your pocket, but such devices would certainly not have been possible without the application of the scientific method consistently over several centuries.
We can also take a more formal look at it. Imagine we start with a random collection of beliefs and, every time something happens, we compare what we observe to what we expected based on our beliefs. Depending on how good the match is, we decide whether to keep our beliefs or change them (or more precisely, whether we should increase the degree of confidence we have in each of those beliefs, or decrease it). Under certain conditions, it can be shown that eventually we converge towards a set of beliefs that are "true". By this I mean that given enough time, the accuracy of our beliefs increases indefinitely, getting arbitrarily close to (though never reaching) 100%. This is the scientific method, which can be seen as a loose application of Bayesian inference.

Note that our updated beliefs depend not only on the observations, but also on our prior beliefs. One might then ask: does it not matter what our initial beliefs are? The answer is that in the short term, of course they will. In the long term, no, as long as you're careful. There are pathological choices for our prior beliefs that can stop us from learning new things. An obvious example is when the initial beliefs are dogmatic -- for example, if we are 100% convinced that the earth is flat, then no amount of evidence can convince us otherwise (this can be thought of as an application of Bayes' theorem). However, these cases can be avoided (Bernstein-von Mises theorem).

In conclusion, we have two kinds of evidence supporting the use of the scientific method. One is empirical: we've simply seen it work in a lot of cases. Another is theoretical: within a certain formal framework, it can be shown that iterated application of the scientific method makes our beliefs more and more accurate. A caveat is that we have no idea how long it might take us to get to a reasonable set of beliefs (it could be much longer than the time humans will be around). We also don't know if the scientific method is the fastest way to improve our beliefs. It is, however, the best we've found so far -- and, again, history abounds with evidence for that.

Of course, in some sense, this is all a bit circular. In its essence, science is the proposition that to get closer to the "truth", one has to observe the world and update his/her beliefs based on the observations. You're trying to do this right now: you're asking people for evidence that the scientific method works. Presumably if this evidence sounds convincing, you will update your beliefs, and think more highly of the scientific method (if not, then why are you asking?). But wouldn't you be applying the scientific method by doing that?

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if scientific laws are accurately stated (to perhaps a painful degree), then they don't claim to be true.  They just aren't false -- yet.

In that regard, science isn't a technique to discover true statements.  It's a technique to discard false statements.  Of course, a tempting philosophical corollary is that after a long time discarding false statements, all that remain are true statements.  But it's always going to be a work in progress, so we can never say with certainty that we've "finally" found truth.

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"Each piece, or part, of the whole of nature is always merely an approximation to the complete truth, or the complete truth so far as we know it. In  fact, everything we know is only some kind of approximation, because we know that we do not know all the laws as yet. Therefore, things must be learned only to be unlearned again or, more likely, to be corrected. ... The test of all knowledge is experiment. Experiment is the sole judge of scientific “truth”. "

Permalink Reply by Dr. Krishna Kumari Challa on January 30, 2014 at 9:25am

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