String Theory – Science or Sermon?

Hello skeptics and others,

I recently came across a question on twitter which went as phrased “String Theory, Science of Philosophy?” and I thought, as I had not done much with string theory, that now would be as good a time as ever to tackle this question which comes up with string theory often. But first, a bit of background on string theory.

String theory is the name given to a set of sums which attempt to explain things about the things we observe in particle physics. It is basically the claim that the 3 spacial dimensions and 1 time dimension we observe in our universe, are the left overs and that there are possibly up to 8 other dimensions which are all just packed in very tight so that we cannot see them. To explain this to you, I will use the same method Stephen Hawking has done.
Imagine a plastic drinking straw. From up close, you can easily see that it is a three-dimensional object, with height, width, and breadth. If you back it up to a distance of a few metres, the drinking straw starts to appear as two-dimensional, with only length and breadth, you can no longer make out the depth of the straw. As you back out further to a distance of about 20 metres, you can only observe one dimension, it only has length, and you can no longer observe the width of the straw.

Now, the other 2 dimensions still exist, but you can only make out one from this resolution, so for all intents and purposes, the straw is 1 dimensional. The same is true with the hypothesized extra 8 dimensions of string theory. They still exist, but we cannot observe them because they have been compressed in so small. It is physicists belief that these extra dimensions, ‘strings’, carry along them the elementary particles which create the four fundamental forces, gravitons, photons etc. in the world of particle physics. String theory is also said to be the most favoured path for the elusive Theory Of Everything (TOE).

String theory often comes under attack for a few reasons, being that it makes no specific predictions about the universe, it is no different from other theories about observed phenomena and there is so far no test of the ‘theory’. These criticisms all have legitimate reasons behind them.

It is true that string theory makes no predictions and it is indifferent about what we are already observing in the universe. String theory has not been of any real use to us yet other than jobs for people to do the maths behind string theory. In that way (except the maths), string theory is just like creationism… it makes no predictions or offer a hypothesis to test.

However, I think that just because string theory has not provided any scientific worth so far, it is in no way something we should give up on. It is a theory which has held up to all that maths has to throw at it, so there are no real internal problems with it, but the real question is “Is this how reality really is?” and that question is a long way off. String Theory is a path worth following, as it could be of value to future scientists. At best it is still only a hypothesis… not a theory, and should be treated as such. But it is worth the time and effort to work with and who knows, it may cough up a test for us, and it is worth waiting around for.

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More on quantum mechanics

Greetings and salutations to all intelligent people in the meta-nation which is the internet.

Yesterday I made a blog about Schrödinger’s cat and the implications it has for quantum mechanics. Today I would like to talk about a more extreme Schrödinger’s cat experiment where the lowly cat is replaced for an actual scientist. This seems like a very crazy experiment to conduct and it is, because the scientist will most likely die, but maybe, just maybe, he will survive and live to test more stuff another day.

To find out why this experiment would ever be done, I will explain to you one explanation of the “one photon acts like a lot of photons” experiment that I talked about last time. The leading interpretation at the moment is that when something happens, say, a photon goes through a slit, or a radioactive atom decays, or you decide not to use conditioner in the shower, all of the possible outcomes are achieved with their respective wave functions, and these happen in different universes. What is interesting is that when something like Schrödinger’s cat happens, there is one universe in the multiverse where the cat dies almost instantaneously, and another universe where the cat does not die at all, and this happens with everything that happens in the universe, and other universes, and more universes. What this conjures up in my mind almost instantly in a tree, and I think it helps describe this well.

Probability diagram

A probability tree which shows well how this interpretation of quantum theory works

Imagine the world as it is now, there are two possibilities right now, you can continue to read this blog, or you can log off (which would be very rude) There will be one universe where you log off, this is universe A, and one where you continue reading, universe B. Now there are two ‘parallel’ universes. There will now be two choices in universe A, you decide to log back on, because you realize how rude what you did was, and one where you stay logged off. in universe B, you have two choices, you stay logged on because this is completely riveting stuff, and one where you do finally log off.

The universe that we do end up being in will be one of those possibilities, hopefully the one where you stay online. But that does not mean that the other universes do not exist, they still exist, but you and I cannot ever get back to that other universe. This explains the ‘one photon acting like lots’ experiments. It also means that occasionally, unlikely things will happen, like the cat not passing away. It also means that out there, in the multiverse, there is a universe where I am having a conversation with Michael Jackson and Elvis Presley.

That’s all for today, I will leave you with a quote from Michio Kaku, ” In fact, it is often stated that of all the theories proposed in this century, the silliest is quantum theory. Some say that the only thing that quantum theory has going for it, in fact, is that it is unquestionably correct.” Michio Kaku, a theoretical physicist, co-founder of string theory, a futurist and a popularizer of science.