Wednesday, November 27, 2013

Promoting Gravity

It's not news and I haven't seen it, but there was a movie released recently called Gravity. Great concept I guess, and from what I have heard, it's a suspense thriller, but hey, this isn't a review.

What caught my eye about this movie was the fact that there were some people (some of them in the movie, some of them not) on a press tour, doing interviews etc about the movie Gravity. The thing is in the lead up to the movie, when all these press interviews were happening...

I didn't know it was a movie!

So for me, all I saw was a couple of people like Sandra Bullock and Brian Cox promoting what I could only guess was the concept of gravity. This is a brilliant idea.!I was, to be honest, a little bit disappointed when I heard that there was a movie, because it means George Clooney wasn't promoting science, he was promoting a movie that has little science in it.

Nonetheless, what a completely brilliant idea. Let's get some movie stars promoting physical concepts and laws. We can continue with "Electromagnetism," "Latent Heat," The Bernoulli Effect," "Total Internal Reflection," Half-life Decay," "Newton's first." Then even move into other science disciplines like "Plate Tectonics," "Evolution", "Bonds...Ionic Bonds." I've even made a trailer for the upcoming blockbuster "Superconductors!"

Some of those concepts really do sound like good movies that I'd watch. So I'm going to go and do it. I'm going to create movie trailers for different physics concepts and perhaps they'll get picked up by the big studios and turned into feature films, and then we will have film stars promoting Physics concepts!

And here is my trailer for the movie Gravity.

Thursday, November 14, 2013

Science for poets part 1

I'm not much of a poet (I did Physics for a reason!), but if I was, this is what my poetry would look like.

The first one is from personal experience of a guy in the Army reserves who thought he was a bigshot. While doing pointless pushups, he asked what each of us do, all responses had something to do with being self-employed and utes, except mine. The line in the poem is verbatim. This little interaction is basically the moment I decided that I was not a good fit for the army.

Argument from silence is too often seen as Guilty until proven innocent. Think of the last time you heard on the news, "They were unavailable for comment" and the implication in that comment.

The third one, Ad hominem, basically means an attack on the person, not the argument. I wanted that one to be a quickfire set of insults, as insults sometimes are. Whenever someone resorts to ad hominem in any argument, you have essentially won!

Argument from authority
Wasting time and taking too long.
An ignorant order to hurry up and wait.
Move a car from here to there,
In the rain, 
And back.

Your two thin strips of authority,
Watered down by the rain.
Your orders and not mine.
I'm gonna walk away

Pushing the ground by an insignificant amount.
Immeasurably small use of orders.

Others working, driving, fixing
The punishment for that,
"Gimme 20"
Me I study Astrophysics...
"Huh, Whaddaya need an education for? 
Gimme 50"

Your two thin strips of authority
fortified by the walls
Give you no right to pretend.
I'm walking away

Argument from silence
No comment! 
But believe me.
No comment? 

Not here,
to say

you choose
I win, 
you lose

Ad hominem
Bad smell, wet towels,
Too short, glass house

Sarcasm, experts
Fuck you, that hurts

Insane, nasty
Not least and not lastly

Judgement, absurd
Stupid, bad word

Irrelevant, what a hack
Targetted personal attack 

Pathetic, ultimatum
It's just ad homenim

Shut up, there's more
Ugly stick, incredible bore

No legs, insults
naive, your fault

You're wrong, out of line
Your stuff's not as good as mine

Infantile, piece of crap
Deaf and blind, take that

Loser, laymen
It's just ad homenim

Wednesday, November 6, 2013

Do you believe in the god-particle?

Today I was giving a presentation to some young students about Physics, and at the end I asked them if there were any questions. This is the ripper question I got:

"Do you believe in the god-particle?"

Where do you start with a question like that? What an opportunity to talk about science! how deep do I go? do I start from scratch? did he really mean it like that? It floored me. I didn't expect it.

I'll deconstruct the question, then answer it.

"Do you believe..."

I don't believe in science. You can't do that. It's fact based on evidence, observation, theories and laws. It's like asking if you believe in the letter N?  Neil deGrasse Tyson has a great quote (and a pretty funky vest) on this. "The good thing about science is that it's true, whether or not you believe in it"

Faith and science are very different things. Faith demands that you have to believe something for no logical reason, just because it is written or told to you. There is no questioning in faith, in fact questioning faith makes no sense, the answer to your questions will always end up as, "It just is.""Why?, cos it just is!" So when I'm asked a question about faith in a Physics context, it is a non-sensical question. Science, or in this case Physics, is a pursuit of knowledge through experimentation and questioning, making hypotheses and then changing them, if needed, based on evidence and research. There's nothing to believe in here, it's a process. I can believe that when I do the shopping there'll be some ripe bananas there, but I can't believe in the process of going shopping. 

I find that if you substitute the work think for believe, it makes my point clearer. "I think there'll be some ripe bananas at the shops," and "I think shopping" It doesn't make sense. "Do you believe in Physics?" is just as non-sensical as "Do you think Physics?"

The god-particle

The Higgs boson has absolutely nothing to do with god, and everything to do with many, many intelligent and hard working scientist, experimentalists, theoreticians and all the others that work at the Large Hadron Collider. There are rumours that say that the name came from the fact that it explains everything and therefore creates the response "god-damn" (shortened to god) particle, but who knows if it is true or not. To me it doesn't matter. That isn't its name and no-one I know calls it that.

The Higgs boson was a missing piece in what is called the standard model in Physics. Sort of like the particle physicists version of the periodic table of the elements. It is a nice neat table and shows what goes where. Depending on the position of the fundamental particle in the table, gives it different properties etc. the fact that the Higgs particle was missing, didn't mean it was a complete mystery, we had a pretty good idea of where to look for the particle. 

We have now found a Higgs boson. Notice I said a Higgs boson, not the Higgs boson, there's a difference. If  it is the Higgs boson, then we all give each other high-fives, cos we got it right. If it's a Higgs boson, then, again, we get to give each other high-fives, cos now we get to make new physics. No matter what it is, and we still don't know, (the latest is that there is "evidence to suggest..." that it's the standard model Higgs) is that physics is changing in front of our eyes, and I find that very exiting.

The Higgs boson is no longer something we think is there, we know it's there and we can show that with a silly amount of certainty. It is no longer theoretical. We have done many experiments and will continue to do more experiments to figure stuff out about the Higgs boson. Next year when the LHC is turned back on, it'll be cranked up to twice the energy that it previously was, there fore we'll probably see more Higgs bosons, more evidence, and hopefully some more new physics

So to answer the question, finally. 

No, I don't believe in the god-particle. I know there is a Higgs Boson.

I'm not sure the student who asked the question was expecting the answer I gave hime (which I admit was a light hearted rant, but a rant nonetheless!), he probably just wanted to sound like he knew what he was talking about, or he was completely trolling me, or he was actually interested and he'll leave that question now with a netter understanding of the Higgs boson. Who knows. It did floor me though. I like the fact that I can answer This. I could have said yes (which I think is what he was after), I could have said no, which is what I meant, but instead I tried to communicate physics to him. I hope I did alright.

tl;dr No

Friday, November 1, 2013

Half-life cake

The half-life cake is a bit of science that happens in most offices, staff rooms, boardrooms and committee meetings around the country. And probably a lot of social functions as well. It's beautiful bit of science often overlooked. At most, in the places I have worked, it's noted and laughed at but no more than that. I think the half life cake should be celebrated, this is my attempt to celebrate it. What better way to celebrate than with cake!

When a cake is presented at a work function or event, it is generally cut up into eight pieces. An eighth of a cake is not too big of a piece and also not to small. Knowing full well that there are more than eight people to give some cake to, cakes are still only cut up into eight. This has always amused me!

And of course, those fairly sizeable pieces of cake go quite quickly. but only seven of them! The last one is always left over. Nobody wants to be the person to eat the last cake. there must be some unwritten rule that you can't eat the last bit of cake. But because there are some people who haven't had cake (or some that might want more), they'll cut it in half. You have to cut it in half, you can't go less than that, because you want as much cake as possible and you can't go more than half, that's greedy. So we are left with one sixteenth of the original cake left. Then another cake eater wants their slice, so they'll repeat the process. They're happy cos they have cake and they didn't finish the cake, and we have 1/32 of a cake left. A third person repeats this, and at this stage, the cake consumers are getting frustrated, their cake ration is diminishing, and the (depending on the cake) cake's structural integrity is being compromised.

What we are seeing is the decay of the cake over time. Each time period, half more of the cake has decayed into someone's mouth. Theoretically, and interestingly, if we were to keep at this, it would take avery long time to actually have no cake left, we would have to get down to a single molecule or atom of cake, (I forget which number in the periodic table cakium is...) before someone would have to eat the last bit.

In science we don't use this as a measure of how annoying it is to cut up really small bits of cake, we use this as a time measurement.I know that every time someone goes to grab some more of the last bit of cake, they'll cut it in half. leaving half left over. that means that in one time period, or iteration, the piece of cake has halved its size. So the next time someone goes for cake (the second iteration) it will be half that again, or one quarter it's original size. It'll be an eighth the original size after three iterations, a sixteenth after 4 etc...This time measurement is called the half-life.

Why is this useful? It's useful because as I said before, we would be here for a very long time in order to figure out how long takes for things to completely disappear. In fact with radioactivity it is impossible to figure that out, due to that fact that this process is not only almost infinite but completely random. So in order to make sense of how long a cake will last (which is an unanswerable question) we ask how long until one half of the cake has gone. That we can answer!

If each iteration of the cake decay was about 5 minutes, we would say that the half life (that is, the time it takes for half the cake to decay, is 5 minutes! Easy. You can even see that on the graph. If you go to the amount of cake of 0.5. You'll see that the corresponding value on the x-axis to that is 1 (where 1 iteration is equal to 5 minutes). I could even ask you how much cake will be left after 15 minutes? and you would say "according to your graph...0.125 of the original piece" This is a much better answer to the questions of how long will it take fort hat cake to go away. Much better to give a number as an answer rather than, "Forever." Some cakes will have much longer half lives than others. This will give us an indication of it's stability or rate of decay. A cake that decays very quickly is unstable.

Like cakes, elements are radioactive too, some elements decay faster than others, and some take thousands of years. Due to the fact that half-life decay os very predictable, even though when each part of the element will decay is completely random, we can make some very precise measurements of how old something is, based on the amount of radioactivity it has left. This'd almost be like judging how good a cake is based on how much of the last slice is left after a certain time.

So I have either inspired you to regard the cutting of the cake in a new way, impressed you with another place where great science can be found, and maybe even educating you a bit about half-life, or I have way too much time on my hands and think about this stuff too much. Either way, the cake, in this case, is not a lie.

Horse racing

As mentioned in a previous blog post about climate science, I really don't like horse racing. It's physical and emotional abuse of horses at best. Here are my thoughts from that post:
"I can't stand horse racing. It's simply justified animal abuse in my opinion. If I were to hit you with a whip to make you run faster, I'd surely be done for physical abuse! I've been told however that jockey's don't always hit horses, they pretend to hit them most of the time...which is worse! If I was to pretend to hit you with a whip in order for you to run faster, I could be done for emotional abuse."
I'd like to add to that little rant with this. If there was no-one betting on which horse would win, it wouldn't be a very popular sport, which, by extension, means that the only reason this sport exists, is for gambling, which makes it less like a sport, and more like...gambling! To make some people very rich, and others very sorry that they wasted their money.

Horsehead nebula. We use parallax
to measure Astronomical distances
The only good thing about horse racing is that it uses (or used to) parallax at the finish line to determine the winner of the race. parallax is a very important concept in science and it seems to be left out of a lot of places.

So what is parallax?

Parallax is the observation a fixed object from different perspectives in order to calculate its distance from the observer. The best example is to do it yourself. Put your thumb up and extend your arm out. Make your thumb over up something on the other side of the room, a clock, or light or something and close one eye (it doesn't matter which one). Now keeping your thumb where it is, open the other eye and close the one that was just open. Your thumb has now 'shifted' and it is no longer covering the thing you originally covered. This is parallax. Your point of observation move, therefore the object you were observing appeared to move. With some very simple maths and similar triangles we can calculate how for away the light (or clock...or whatever) is, based on the length of your arm and distance between your eyes.

This is how we measure astronomical distances. We assume that the stars that are a very long way away, don't move much (they do but we don't see it) and we measure a stars position in the night sky in January, then again in July, when the Earth is on the other side of the Sun. the distance that the stars relative position has changed tells us how for away it is. Cool!

The point is though, that if you change where you observe from, you will change your measurement. This is where parallax error comes in. If I measure a volume of liquid standing up, then the same volume of liquid while I am sitting, I'll be observing the liquid from different perspectives therefore giving a different result. Not good!
Japan World cup 2. Horse racing done right!

It's exactly the same with Horse racing. Two people can have different opinions of which horse won a race depending on where the saw the finish line from. Even if they were both next to each other, they would still see the result differently. To get around this, we use a mirror at the finishing post of a horse race.

The mirror helps us eliminate parallax error. The way we do this is to line up the horses nose, with the image of the horses nose in the mirror. When the two things line up, we know for sure that we are looking at the finish post straight on and that will tell us which horse finished first. Lining the object and the image of the object makes sure that we are not changing our perspective. This technique is used in physics all the time to either measure the distance to something, or eliminate observational error.

So next Melbourne cup when we are all experts on horse racing, you'll find me talking about parallax, not the odds of some animal that we make run fast in winning money for us. If I ever owned a horse, I think I'd call it Parallax Error!