VIDEO: Christmas Lecture 2010 – Weird Physics

 

On the 17th of Dec 2010 we held our second Christmas Lecture on the topic of “Weird Physics” – all those mind-bending things that physicists talk about when describing how our universe works, like parallel universes, black holes, cats that were dead and alive at the same time and time travel. Dr Paul Stevenson lead the lecture that covered some of physics most confusing topics, including relativity and quantum mechanics, in an accessible manner enjoyed by kids and adults alike.

After the lecture there was a festive reception with refreshments, mince pies and some exhibitions of some of the ideas covered in the lecture – as well as a quiz, with the winner walking away with a pretty nifty science kit to take home. Like last year, there was also a bookstall provided by the local children’s bookshop Rhyme and Reason, also featuring some science books for adults, too. To watch the highlights from the Christmas lecture check out this video:

We had a great time organizing it and the feedback from those who attended mirror this as well. We thank the Institute of Physics Yorkshire and North East branch, the university of Sheffield outreach department and alumni foundation for their support, and are very grateful to those individuals who made the lecture possible. We look forward to seeing you this Christmas!

Weird Physics – a quiz

First of all, HAPPY NEW YEAR!

It’s been a great year for Science Brainwaves, we’ve come a long way, and this year we’ll only be bigger and better, so watch this space on news of events coming your way in 2011.

Just before Christmas we held our annual Christmas Lecture, this year on ‘weird physics’ – the mind-bending ideas that physicists use to explain our reality, that include baffling things such as particles being in two places at once, black holes and a cat that was both dead and alive at the same time.

I’ll write more about the Christmas Lecture in my next post, but for now we thought it would be a good idea to publish the quiz that our head of volunteers, Ben Dornan, wrote as the Quiz Master. We had some prizes for kids to do, which were:

1st: Chemistry set plus a voucher for rhyme&reason and a copy of the Horrible Science Seriously Squishy Science Book,

2nd voucher for rhyme&reason and a copy of the Horrible Science Seriously Squishy Science Book,

and the runners up all got a copy of the book.

Below are the questions and answers, a bit of quizzery to pass some time. Of course if you didn’t attend the lecture the answers mightn’t be obvious, but we’ll cover information from the lecture later on, in the mean time Google is your friend!

Question 1: Before Einstein published the theories that eventually made him famous, he had another job. What was it?
Office Clerk
Engineer
International Man of Mystery
Politician

Question 2: Which of these is one of the important insights of Einstein?
There is No Such Thing as Time
The Earth Orbits the Sun
Speed is Distance Divided by Time
The Speed of Light in a Vacuum is Constant

Question 3: In Einstein’s famous equation E=mc^2, what does E stand for?
Everything
(Energy)
Entropy
Einstein

Question 4: Moving fast changes the way we experience time. If one twin left Earth to go on a fast trip in space, while the other stayed, who would be older when they got back?
They Would Both Be the Same
The One Who Left
(The One Who Stayed)
They Would Both Be Younger

Question 5: The Large Hadron Collider in Geneva is looking for the Higgs Boson. What is this particle meant to explain?
Energy
Relativity
(Mass)
Time

Question 6: What was demonstrated by the double slit experiment?
(Wave-Particle Duality)
The Speed of Light
Quantum Tunnelling
The Existence of Black Holes

Question 7: In Schrodinger’s thought experiment, what is the strange and interesting property of the cat involved?
It Has Two Tails
(It Is Both Dead and Alive at the Same Time)
It Doesn’t Age
It Can Travel Faster Than Light

Question 8: Which of the following is NOT a real interpretation of quantum physics?
(The Berlin Interpretation)
The Copenhagen Interpretation
The Bohmian Interpretation
The Many-Worlds Interpretation

 

If you’ve got any suggestions of events you’d like to see next year, get in touch, or let us know on our forums!

May 2011 be a good one for all!

Weird Physics – an Introduction

Guest post By Robin Bisson

 

With Halloween and Bonfire Night out of the way, mince pies comfortably established on the supermarket shelves and town light displays ready to be switched on by a passing celebrity, Christmas is on the horizon. And so too is Science Brainwaves’ Christmas Lecture, a free event being held on the 17th on December at the University of Sheffield, which promises to be a real cracker *groan*. The lecture, titled ‘Weird Physics’, is being given by Dr Paul Stevenson of the University of Surrey.

That physics is weird might seem to be a given, after all physics fans have a reputation for getting all excited over obscure things that happen millions of light years away, having some outlandish tastes in music, and developing a tendency in later life to wear jackets with leather elbow patches. However, we’re not talking about any normal kind of weirdness here; we’re talking about the seriously bizarre world of quantum mechanics, a world in which even the most basic facts about the world get turned upside down. Now, if all that the word ‘quantum’ makes you think of is daytime repeats of Quantum Leap, you’re probably not alone. So to get swotted up before the lecture, and to give you a taste of some of the strangeness to come, here’s an introduction to the weird world of quantum mechanics…

Perhaps the most well known illustration of why the quantum world is at odds with the rest of the world is that of Erwin Schrödinger’s famous cat. Schrödinger proposed an experiment where a cat is placed in an opaque box, in which there would also be a phial containing poisonous gas, one radioactive atom and a mechanism to smash the phial if the atom decayed. If the atom were to decay then the cat would die, but if the atom does not decay then the cat survives. The weirdness comes in because quantum mechanics tells us that until we look at the atom, it is in the state of being decayed and non-decayed at the same time, and the consequence for our unhappy cat is that it is both alive and dead at the same time. “Ridiculous!” you might well shout, which is exactly what Schrödinger was pointing out, all be it in a slightly morbid way – the quantum world does not appear to fit in with the world of big things that we know, in which cats most definitely don’t wander about in limbo between life and death.

To make it clearer what exactly we’re dealing with here, a little explanation is needed. The quantum world is that of atoms and subatomic particles: the familiar electrons, protons and neutrons that we all learned about at school, as well as other more exotic particles. One of the things that quantum mechanics says about these little bits of matter, is that once you have observed them being in a particular place at a particular time, you cannot say for sure exactly where they will be at any point in the future. Instead you can only give a probability of them being in a particular place until you have another look and make sure. So far so normal. After all, we can’t expect to know everything.

What quantum mechanics sneaks in and confuses us with, however, is the assertion that these particles aren’t actually anywhere until we look to check – while our backs are turned they are in one place, and another place, and even another, and another and another place all at the same time, but when we look at them BANG, they are somewhere definite again. It’s a bit like playing “What’s The Time Mr. Wolf?” with subatomic particles, except that instead of you not knowing where your fellow players are, they don’t know where they are until you turn around to look (and also, subatomic particles don’t run away screaming when you growl at them).

If this all seems a bit stupid and it’s obvious that physicists just haven’t understood some basic stuff, like that things can’t be in two places at once, there are some awkward experimental results that show the quantum world simply can’t be like the world we all know and love. For instance, quantum particles get ‘entangled’ with each other, so that if you do something to one of the particles the other particle notices. It doesn’t matter if the other particle is on the other side of the room, the other side of the world or the other side of the universe, it will ‘respond’ when its partner has something done to it. Weirder still, these particles may not even only be particles – quantum mechanics regards them as having some properties of waves, and some properties of particles, something that Richard Feynman called “the only mystery in physics”.

Don’t worry if your brain is beginning to throb alarmingly, the physicists are confused too. Since quantum mechanics was first formulated there has been a raging debate about how it should be interpreted. One interpretation that has steadily gained support is that quantum mechanics only makes sense if we live in just one of many co-existing parallel universes. Every time we look in the box to see the mortal state of Schrödinger’s cat we set off down one leg of the trousers of time, let’s assume the one where the cat is alive, while in the universe of the other leg, the cat has met a sticky end.

While it may be mind-bending to try and understand what quantum mechanics implies about the universe and to imagine what the quantum world looks like up close, the more we understand about it, the more we can manipulate it to do some pretty nutty things. We all know that as long as watertight bowls are kept steady, any liquid inside them is going to stay there, right? Not if it’s a superfluid – liquids predicted by quantum mechanics that creep slowly out of any container holding them (click the link for a video). Even more amazingly, there is some early evidence that supersolids can exist – solids that literally move through each other like ghosts, without being affected. In any case, I think we can all agree that a world with quantum mechanics is a much weirder world indeed than a world without. To find out more, come to the Christmas Lecture, but don’t say you weren’t warned if you lose grip on reality…

 

 

If you want to investigate Quantum Mechanics further, then check out plus magazine’s website for podcasts, news and reports.