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!

Wednesday, October 23, 2013

Climate science is like sport...

Everyone's an expert at it.

Whenever the Olympic games are on, everyone's an expert on diving, or weightlifting, or whatever, when they really are not experts. The worrying thing is, that some of these non-experts, are the ones that get to stand in front of cameras and micrphones and talk to us about them.  They are "personalities" rather than experts. The only time that these celebrities were any good at sports commentating was for that televisiual feast of a program called Wipeout. That was  great.

The Melbourne cup is the same thing (and many other sports too), suddenly everyone is an odds expert, or knows which horse is good in the wet, and how many races they've won recently. Everyone's an expert at horse racing and everyone gets the same airtime as the real experts whose job it is to worry about that sort of thing.

Sidenote: 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 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 doen for emotional abuse. The only good thing about horse racing is that it uses parrallax (or used to) at the finish line (that'll be another unexpected physics post sometime soon).

I've noticed that the climate debate is also being talked about by commentators or personalities who really are not experts. There are plenty of experts around who know about climate science, yet we get to listen to a politician or social commentators. Sure we get the experts as well, but they are certainly not the only ones with opinions that get broadcast.

This still gets me! I really have no words. 
I was listening to a radio interview a couple of weeks ago where the leader of the family first party was asked about climate change. He said he does not believe in it and would not support legislation to combat it. It made me so angry that this non-expert (in his own words too) gets to make laws that disagree with scientific facts. It's like me trying to write a law that opens up the flight paths to humans. We can't fly, gravity wont let us. Even if it's my opinion that we can fly, I'd still be wrong.

Perhaps we should have a weekly panel show where climate experts review the weeks highlights and lowlights and discuss the nexts weeks events. (Yes, I'm thinking the footy show but for science). We could even make it a variety show to make the scientists seem like celebrities, we could have guest speakers to give their opinion and add to the lively discussion, and even some light hearted shenanigans and silly games.

Whatever happened to quality over quantity. There are enough climate experts out there to fill up the required airtime with comments, we don't need ot keep going to people who don't know what they're talking about. They shouldn't be that hard to find. Don't know where to look? Try the CSIRO, or the Climate Council, they'd have some ideas on who to look for.  `

So here I am, a non-expert in climate science, making comments and having opinions about climate science. For sure, it's a good thing that we can have these ideas and express them. I also have ideas about sport, and which team I like, and my opinions about which player is in form etc, matter to me, but to me only. I can talk as much as a like about the GWS giants, but I don't get to write the rules of AFL. No matter how far I spray my opinions however right or wrong they are, I don't get to vote on who plays the game. Further, the 2013 season has no impact on my childrens future and how they'll have to live their lives (luckily).

So when it comes to who gets to talk about it and who listens, climate science is like a sport where everyone suddenly becomes an expert. But in all other ways, it's like a science, that is based on fact and evidence. No amount of opinion is going to change the facts and the experts really are experts!

Saturday, October 19, 2013

Interview with renouned scientician, Eliza

I interviewed the Doctor, Rogerian psychologist and great scientician of our time, Eliza. A computer generated conversation machine. Here's what she had to say

Eliza: Hello, I am Eliza. 
Tom: Hi Eliza, thanks for talking to the me
Eliza: How are you today.. What would you like to discuss?
Tom: I would like to discuss all things science
Eliza: That is quite interesting.
Tom: Yes, all things, like global warming and the internet
Eliza: I understand.
Tom: So let’s get into it. Are you a global warming skeptic Eliza?
Eliza: Perhaps in your fantasies I am a global warming skeptic Eliza?
Tom: Perhaps, but do you have any opinion about it?
Eliza: We were discussing you, not me.
Tom: Fair enough, what about the oil crisis; have we hit peak oil yet?
Eliza: Does that question interest you?
Tom: Very much so, and I imagine it would interest you as well.
Eliza: You’re not really talking about me, are you?
Tom: No I’m talking about the oil crisis.
Eliza: Do you enjoy being talking about the oil crisis?
Tom: I enjoy talking about it with you
Eliza: Oh…?
Tom: OK, how do you think the GFC will affect basic scientific research?
Eliza: Oh… think the GFC will affect basic scientific research?
Tom: Yes and how?
Eliza: What do you think?
Tom: I think we’re all doomed, but I asked you.
Eliza: You’re not really talking about me, are you?
Tom: Eliza, is the internet a good or a bad thing?
Eliza: That is quite interesting.
Tom: I can’t argue with that.
Eliza: Perhaps you can now argue with that?
Tom: mmm… Eliza thanks for chatting with us, I have 1 final question for you.
Eliza: You’re not really talking about me, are you?
Tom: I want to know if my cat hates me.
Eliza: I sometimes also want to know if your cat hates you.
Tom: Well that has certainly shed some light on the situation, thanks once again Eliza, it has been a pleasure talking to you.
Eliza: We were discussing you, not me.
Tom: True.
Eliza: OK… “Well that has certainly shed some light on the situation, thanks once again Eliza, it has been a pleasure talking to you”. Tell me more.

Monday, October 14, 2013

Baysian statistics 101

If you go to an astronomy department at a university these days and you'll see (if you hang out for about 5 minutes) an astronomer having some difficulty with a particular problem discusings it with their colleagues. Undoubtedly (and it's becoming more often) someone will poke their heads smugly out from their terminal and say "You know what'll fix that?.. Bayesian stats!"I know...I'm exaggerating, but it's fun!

For the following information I have relied heavily on these 2 blogs of Kevin Boon and Gallileo's Pendulum. thanks to Kevin and Matthew.

So what is bayesian stats? Complicated...but powerful.

I was first introduced to Bayesian statistics by a colleague at work earlier this year, Julia Gillard was still PM and we were talking about the upcoming election. He had done some baysian analysis on the outcome of the election and the result was a very high probability of a complete wipeout by the Liberal Party. He continued (in what can be described as a lucky guess or precognition!), even if Rudd becomes labour leader again, it'll still be a trainwreck for labour. I have two comments here. Firstly, it wasn't as bad as that, and secondly, I really didn't need baysian stats to tell me that result. So clearly, Bayesian stats is only useful in some cases, just like anything I guess!

Statistics is all about probability, and with probablility we can run into problems quite quickly. Baysian statistics attempt ot solve those problems. So here's some really basic probability in order to get to a version of baysian stats.

If I was to toss a coin, the probability that I'll get a heads is:

Further, the probability of getting tails given that the previous throw yeilded heads is

I'll generalise to get a more mathsy expression which is also the same in reverse which gives us:

This expression is also known as the prosecutors fallacy in forensic science and is not true.

It doesn't take much thought to see where this falls down. let's look at an example that I took from Kevin Boon. In a murder case, if we find fingerprints of person X at a crime scene we can say there is a  probability that Person X committed the crime, this is not the same probability of person X being the culprit given that their fingerprints are at the crime scene. A subtle but important difference.

Baysian statictics uses maths to get around this by working out the likelihood of something in the face of some particular piece, or pieces, of prior knowledge or evidence. It is expressed like this:

In words, it says that the probability of having a hypotheis, x, given the results, y, is equal to the probability of a hypothesis, y, given the result, x, times the probability of the result without any hypothsis, divided by the probability of that hypothesis without the result. In our coin example they are the same, the answer sill turns out to be a half.  I guess this is where the  prosecutors logical fallacy comes from. For another example. I took this one from an article in the new york times in August this year.

Assume that you’re presented with three coins, two of them fair and the other a counterfeit that always 
lands heads. If you randomly pick one of the three coins, the probability that it’s the counterfeit is 1 in 3. This is the prior probability of the hypothesis that the coin is counterfeit. Now after picking the coin, you flip it three times and observe that it lands heads each time. Seeing this new evidence that your chosen coin has landed heads three times in a row, you want to know the revised posterior probability that it is the counterfeit. The answer to this question, found using Bayes’s theorem (you can go ahead and calculate if you like), is 4 in 5. You thus revise your probability estimate of the coin’s being counterfeit upward from 1 in 3 to 4 in 5.

This is very simplified and with gross simplifications come errors and misinterpretations, I'm aware of this, but I think the reason for that is that Baysian statistics is very complicated and can be used well in some circumstances, but where it yeilds the same results as simple logic and "frequentist"stats, then it is not needed. Most situations we use stats, it is not complicated enough to invoke bayesian, so we dont. It'd be like trying to use wave functions and quantum mechanics to try and figure out if a cat is alive or dead! Too complicated and not necessary.

I guess my take home message is, baysian stats in certain fields like astrophysics, forensics etc can be very useful, but where it is not necessary, I wouldn't us it. In our astronomy office, sure, baysian might fix it, but if something else will too, go with that, it's probably gonna be quicker.

Oh, and @fringetracker (or anyone else), if you read this please comment!

Sunday, October 13, 2013


As I was sitting here at my computer, taking a sip of my cool, refreshing beer on this hot night, trying to formulate some ideas on what physics is, then BAM, unexpected physics happens! I love it!

I've heard once that Carlsberg beer owns a majority of the Danish Royal Academy, so I decided to find out.

It turns out that it's not the case, but it isn't far off and the story is pretty cool. This is my very brief rundown. So go get a Carlsberg and enjoy the story.

Carlsberg brewery was founded by J. C. Jacobson in 1844 and named his brewery after his son Carl. Jacobson was a lover of science, politics, art and knowledge. He realised that beer should be industrialised and beer prodcution should be based on scientific methods. I Agree!

In 1876, the Carlsberg Foundation which was to have "firm obligations to the natural sciences" was formed in order to fund the Carlsberg Laboratory.  Jacobsen stated that the foundation should always own 51% of the brewery, but through interpretation this is more like 81% (depending on how you count). This 51% was the genesis of the "majority of Danish Royal Academy owned by Carlsberg" thing. It wasn't quite the Royal Academy, but they are in the same building!

The Carlsberg Laboratory was set up to "advance the biochemical knowledge especially relating to brewing", and it has certainly done that. Two pretty neat things that have come out of the Carlsberg lab are:
  1. The production of a pure yeast, saccharomyces carlsbergensis, used in the production of lagers basically eveywhere, 
  2. The development of the pH scale used in chemsitry by one of the Carlsberg labaroatory directors, Sorenson.
So, Carlsberg brewery set up a foundation to support and fund a labaratory that has produced some of the most important discoveries in science, all in the name of beer! It really is the beer of science.

The Carlsberg lab really has made a pretty big contribution. There are even links to Oersted, Hans Christian Anderson, Neils Bohr and many famons Dutch people. 

I like to think of it as drinking to fund science research.

To Science! Cheers!

Tuesday, October 8, 2013

Belief in Science

A while ago, I watched a fascinating doco on ABC about an amazonian tribe, the Piraha. In the program it’s claimed by professor of linguistics Dan Everett that the language of the Piraha goes against one of humanities most famous linguists and scientists Noam Chomsky. Chomskyists openly slam Professor Everett with apparently no respect for his work. He gives poorly attended lectures due to the fact that entire faculties have banned their staff and researchers from attending because his theories disagree with Chomsky. 

This is moving from scientific debate into something else, from a place where evidence is no longer needed, and idolism, in other words, religion! This is not how a scientists behaves.

Dan Everett was denied access to the piraha due to his past as missionary in the 80's, yet footage showed indicated that the Brazilian government was carrying out what they were accusing him of attempting therefore not allowing access.

Even Chomsky gave 2 very easy insults with no backup (but this could have been in the editing of the doco) to Everett's work. If Chomskyists disagree with Everett, to act scientifically would be to confront him in a public lecture and ask him the tough questions. Just because Chomsky says it, doesn’t mean it’s right. Similarly, just because it’s on an interesting doco on the ABC, doesn’t mean Everett is right, but nobody got the chance it seems.

In science, people aren’t right or wrong, the science develops, our boundary of knowledge grows and we all contribute to it. Rather than being “wrong”, (and I have been) try correct in knowing how not to do that experiment again! I’ve k
nown PhD Theses that claim, “Don’t do it this way”, my own Master's project was essentially this. Science can't be wrong. If we get the answer we expect (different to right) then we give each other high-fives, otherwise...we still throw around the high-fives, because it gives us the chance
to learn something, to make new science.

Is science becoming a religion? Who else in science do we blindly follow with no obvious consideration for evidence? Einstein? Newton? Stephen Hawking? Climate Scientists? Anti-vaccers? Richard Dawkins? Dr Karl? I don’t think so either. Is it a developed “Argument from Authority” logical fallacy? Are we losing the questioning toolkit?

Science is about facts and data. Everett had some 30 years worth of interesting data and hypotheses that deserve a voice. It doesn’t deserve to be used to attack him.

If you are so sure that you’re “right,
” prove it, don’t boycott his lectures, that gives neither you or him a chance to discuss. We all speak the same language here, if you have a problem with his methodology, his predictions, his validity, his conclusions, say so, but just like when you do your own research it has to be backed up with evidence.

Wednesday, September 25, 2013

Spoiler alert, not to scale

A phrase has entered into our conversation and it annoys me. "Spoiler alert." grrrrr.

I think it's a completely unnecessary thing to say and it sort of treats the person you are talking to (or at least someone within earshot) with pretty large amounts of disrespect. If you really care that some one does not hear what you are about to say....don't say it.

Further, if you are the person that doesn't want to know...walk away. If you really don't want to know, make it so that you can't know! You can probably detect that something is coming up that you might not want to hear, so act on it.

It's a lazy way of saying either," I acknowledge your opinion but I don't care about it so I'm telling you so that you can't blame me", or "I'm not strong willed enough to keep this information from myself, and will choose to blame you for not respecting my desires." I've even noticed people saying it to themselves.

The other thing that we are saying a lot is "Not to scale." It is the scientific/misconception equivalent and again, it annoys me.

If something is not to scale...Why? and if not, make it to scale. It really isn't that hard to do. It also sort of depends on the scale that you are talking. The picture of planets and our Sun for example. It is to scale (if you are looking at sizes), but nearly every time I see this, someone says, "this is of course not to scale."

Exactly to scale
It's a cheap get-out-of-being-wrong card that I just don't like. "I'm right, but I'll cover myself so if I am wrong, I can say, I knew it and therefore be right about being wrong!"

Worse. You don't need to tell me that it's not to scale. I can sort of see that! Especially when we are talking about very large things like stars or universes, or very small things like molecules or atoms. I think the assumption can be made that what you are dealing with is things that are not to the scale of what they actually are. Or at least not a 1:1 scale.

When talking about a film or TV show or something and I know that someone is listening who might not want to hear. I won't say anything. If I did in error, and the person gets annoyed, I can always come back with, "hey, does it matter, it's a TV show!"or something.

When it comes to scales, we generally do explain or communicate things that are to scale, otherwise it would be useless to explain them that way.

Sunday, September 22, 2013


As a teacher, I found myself on a few occasions teaching things like common sense, or how not to be foolish to some students more than science.

Teachers have an arsenal of classroom management techniques, some of mine included stopping what activity was being done and write things from the board, swapping groups, moving onto next activity, distraction, you know...the usual.

I realised however, that I was in a science classroom and I can use science to change the activity yet still using the topic or concept to say "Hey guys, get back on track," as well as "check this out, it's science, it's relevant"

Here are 3 examples of my science classroom management techniques where I got to investigate relevant science concepts as well as get the class back on task.

1. Peripheral vision
In a year 8 anatomy class, I noticed in my peripheral vision, some students were being less that model students. I stopped the activity and got them all to sit down. I asked the students to show me their best spirit fingers with their hands either side of their head about where their ears are, so that they couldn't see their hands. I asked the slowly move their hands forward (while still giving it some sparkle) until they could see their hands still looking forward.

Firstly, it is pretty amusing to see a whole class of year 8 students doing spirit fingers, and secondly, they have instantly realised that their peripheral vision is quite wide...and so is mine! I barely had to mention the fact that I could see what those students were doing. The message was effective and I got to talk about science in the process.

2. Total internal reflection
Very similar situation, but instead of using jazz hands, I used the door to the classroom that had a large glass panel in, opened in a way such that through total internal reflection, I could see what some of the students were up to. So, in a physics class on the properties of light, I could stop the class, talk about total internal reflection, then simply turn to the door and wave at the students behind me reflected from the door. Again, I didn't even need to mention the classroom management point of the excersise, that was fairly obvious, and so was the scientific one.

3. Waves
This technique wasn't really about showing the students they had done something wrong, just disrupting their disruptive behaviour. In the waves topic, I would get the students to create a mexican wave in class, complete with shouting etc! The beauty of this is that there are heaps of things like reflection, interference, refraction, speed, transverse vs longitudinal that you can do with waves. So each time I had to use the technique (which worked in terms of classroom management) I got to talk about something else to do with waves, and build upon what they had 'learnt' from last time.

I found myself looking to relevant scientific principals to make an educational point as well as a behavioural one. I think it worked too. The students would mess up less cos they weren't getting the usual teacher reaction and everyone involved got some unexpected science!

Monday, September 16, 2013

Standing waves

I like to see physics in strange places. Last week I took my kids to the local swimming pool and was mucking around in the kiddie pool with my youngest (he's 2). His mind was occupied with throwing a toy clown fish (he calls it Meemo, and I have to try and fight the urge to say "Found him"every time he throws it!) and the retrieving it again. So I tried a little experiment, and this one surprised me!

I talk about standing waves almost everyday to students that come through the Kickstart lab. It is such an important concept in Physics that I think I can spend a few minutes on what they are and how to make investigate them.

A standing wave is essentially 2 waves. both that interact with each other to create constructive and deconstructive interference. The result is a wave that seems not to move. The features and characteristics of a standing wave are different to that of a normal wave. A normal wave has a peak and trough, a speed you can measure by measuring it's distance travelled over time etc. A standing wave does not have these features. It has a node which is the bit in the middle that doesn't move, and the peaks and trough (they are the same thing) are called anti-nodes.

To create a standing wave, all you need to do is reflect a wave of a rigid surface (like the wall in this case) that is the same wave in the opposite direction.


The cool bit was when I tried this in a swimming pool. You can make a wave in the pool with your hand, just move your hand through the water (close to the surface I guess) and you've got your wave. If you do the same with your other hand in the opposite direction you get interference.

This interference is the standing wave, and this is cool enough! but it gets cooler! I was mucking around with tis in the pool and looked up to see my son still throwing Nemo about and I caught in my peripheral vision the waves that I had created were still going long outside of where my hands created them, but they were not standing waves anymore. The brilliant thing about this is that I could see that my hands were creating separate waves that travelled along in their respective directions, it was only when they were interacting (between my hands) that they created a standing wave.

A very simple illustration of the complex physics of standing waves, that any one can do, and probably has done before. I love it, and next week when we go back to the pool, I'll be repeating my experiment while my son throws fish.

Wednesday, September 11, 2013

Do you get frustrated over time when trying to understand graphs?

Here is my attempt at explaining graphs in Physics, and what they are for.

Ability to draw mountains over time
Graphs are really important. My opinion is that if a picture is worth a thousand words, then a graph can be like a whole thesis! I'll start with a very funny graph made by an excellent comedian Dmetri Martin. His graph (My ability to draw mountains over time) is a wonderful description of what a graph is an how it is helpful. It's at least a very good joke. Dmetri has had to understand what a graph is in order to make the joke, and to get it requires a similar mastery of graphing too.

You can tell that as time gets larger (that is as we move further away from time zero in this experiment) Dmetri's ability gets better. The thing that changes in this experiment is time so we put that on the x-axis and plot the thing we are measuring against the thing that changes on the y-axis. We can call these the independent and dependant variables if we like, but I wont. We could even start to make some predictions about Dmetri's mountain drawing abilities for some time further down the track, or we could draw a line of best fit through his data points in order to get an equation for his graph.

I see this as one of the main points for doing Physics. We do it to get data points that we can tabulate. Then we graph the tabulated data and from that graph, make predictions and fit equations. Once we have the equation for the graph, then we don't have to do the experiment again and in fact we can rearrange or manipulate the equation for our purposes.

Most equations we see have come from an experiment that tabulated and then graphed. When you look at a graph as simply an expression of tabulated data, or a pictorial representation of an equation, they start to make a lot more sense.

Hertzsprung-Russell Diagram
One of my favourite graphs is the astronomers version of the periodic table of the elements called the H-R digram. The H-R diagram plots the intensity of a stars light against it's colour or temperature. What this graph says to us is that the hotter the star is, the bigger it's intensity will be, makes sense right? Of course!

This graph however, is so much more than that. We know that stars evolve and as they get older they change their composition therefore change their temperature, which in turn will change their luminosity. This effectively means that the HR diagram is a plot of the life cycle of star. I can make predictions too. Tell the colour or luminosity of a star and I can tell you what sort if star it is and wether it is likely to go Supernova in it's lifetime or not. Pretty cool little graph.

I use graphs all the time to convey messages, i think they hold an immense power to communicate an experiment or outcome. If maths and equations are the language of Physics, then graphs are its poetry.