Wednesday, May 21, 2014

Physics and more physics

Today, we went to the Open Day at the NPL in Teddington.  The NPL is a big building full of physics.  Some chemistry, but mostly physics.  And it's proper physics.  Lots of it.

It's hard to explain just how much fun it is wandering around the NPL.  It reminded me of one of the better BBC science documentaries.  You know the ones.  On BBC2 or BBC4 and presented by a scientist who loves their subject.  It was like one of those, but one that you could walk up to and touch and ask questions about.

So much stuff I could talk about, so I'm just going to present my ten favourite things from the day...

1. A very echo-y room

The reverb chamber is a small-ish room where things echo. A  lot.  there are no parallel surfaces and no right angles.  Standing waves can't easily get set up.  A single noise will reverberate around the room for 30 seconds with the door closed.  Having a conversation in that room involves a lot of whispering and straining to hear above all the noise.

2. A not-very echo-y room

The first of many spiky rooms.  The spikes mean that almost all the sound which hits the walls is reflected against another spike rather than back into the room.  The silence was almost deafening.  The deadest space I've ever been in.

3. A very cool hologram or two

Not just a dodgy green globe.  Full colour holograms so real that you have to get VERY close before you realise they are not real watches and medals.  Full colour holograms are hard to achieve thanks to the different characteristics of the three component holograms you need to create.





4. Counting electrons

The ampère is currently defined in terms of Ampère's law.  These guys are trying to define it in terms of the flow of charge.  They are doing it by letting electrons pass through a space one at a time and counting them.  Roughly speaking.

5. Redefining a kilogram

The kilogram is still defined as the mass of a block of metal just outside Paris.  All of the other SI base units have less prone-to-wear-and-tear definitions.  The leading proposal is to use a rather nifty bit of kit to define the kilogram in terms of Planck's constant and the charge of an electron.  The brilliance here is that the kit to do it is really not that hard.  With A-Level physics and a bit of mathematical jiggery-pokery you could understand what's going on.  But the brilliance comes from setting it up in such a way that so many of the terms cancel meaning that you're not really concerned about the construction mechanics of the kit itself.

The other possible method of defining the kilogram involves creating a single crystal of silicon in the form of a relatively large sphere, measuring the sphere, using the crystal structure to turn that measurement into a number of atoms and then define the kilogram that way.  Also very cool.

6. Applying force

Big machines which hang weights from things to generate known force.  The fun here is that the equipment of so accurate that the weights have to have different mass in order to generate the same force, as the metre-or-two difference in height of the weight is enough for the difference in the force exerted by gravity on the weight to be different enough to be measured.  On the biggest machine, the top weight is 3g more massive than the bottom one, yet it exerts the same downward force.


7. Blowing up balloons

Take a balloon. Inflate it.  Put it into liquid nitrogen.  The air inside turns to liquid and the balloon shrivels up.  Take the balloon out again and lay it on a desk. The air turns back into a gas and the balloon inflates itself.  Such fun!

8. Firing lasers at things

Take a sample.  Fire a laser at it and measure how hot the other side of the sample gets.  Sounds easy.  Not really. Great fun, though.

9. Telling the time

The second most accurate clock in the world.  It's not actually used to tell the time.  It's used to calibrate the clocks which do tell the time.  It's still cool though.  Though it'd be cooler if it had a minute and hour hand going around on it.


10. Science

The best thing about the day, though, is knowing that there are so many people in the world just as nerdy and interested in physics as me!

Monday, May 19, 2014

In defence of Christianity

It's been quite a few years for battering Christians.  Firstly, a Christian says that the floods were caused by the gays, and then UKIP start to mention Christianity in the same breath as some of their other rantings, and the two become linked together.  It's simply not fair.

Christianity is not a political party.  It's not a political standpoint at all.  It's simply a name for the collection of groups of people who have certain faith.  To say that because one Christian says something, that's what "Christians" think is as fallacious as saying that you saw someone with red hair in a restaurant the other day picking the tomatoes out of their salad, and therefore all ginger people must hate tomatoes.

I should declare an interest at this point.  I am not a Christian.  I'm not a Muslim either. Nor a Jew.  (Although with my Mother's mother being Jewish, I know some would argue the last point.)  But anyway, I am an atheist.  That means I don't believe in God.    However, that does not give me the right to treat those who do believe in God with anything other than the respect and tolerance I would expect them to show to me.  Just because I don't believe in God, it doesn't mean that I have a right to ridicule those who do.  Tolerance must work both ways.

There has been a lot of debate recently about whether the UK is a Christian country.  However, I think that debate missed the point.  I don't care whether the UK is a Christian country or not, although I am not in favour of the UK being a Christian state.  By that I mean that the state should be secular.  That is, that no church nor group within any church, should have any more access or right of influence over government than any other.  Nobody should be given privilege because of their faith - but neither should anyone be denied privilege because of their faith.  That does mean I am in favour of disestablishment of the Church of England, but I'm certainly not in favour of the dissolution of the Church of England.

The difference between a secular state and an atheist state is important.  An atheist state might say that a worker couldn't wear a Christian cross around her neck to work.  A secular state should support her right to do so in the same way it would support freedom of expression to others.

I should declare another interest here.  I'm also gay.  In these times, "the gays" and "the Christians" are often portrayed in the media as being warring factions.  Christians are portrayed as being consistently against gay rights, and "the gays" are portrayed as a lobby group who would seek to destroy the power of the church.  The fundamental flaw in all of this, of course, is to presume that there are no gay Christians.  I know two or three at least.

The media loves to set groups of people up against groups of people.  The media (and Twitter!) doesn't do well with representing the views of individuals, but enjoys attributing an opinion or statement to large groups of people rather than to just one.  One Christian says "the floods were caused by gays getting married" and suddenly Twitter is full of ill-informed ranting against Christianity.  Then it's full of rantings of Christians talking about being marginalised and then the Daily Mail draws the battle lines and reports the waging war.

In my life I've had people say unpleasant things about the fact that I'm gay.  Some of those people have been Christians.  But never once would I hold their views against anyone else who happened to be a Christian.  If a black person did something unpleasant to me and I held that against all black people I met- then that would be unacceptable.  Why is saying things about "Christians" acceptable when if we swapped "black people" or "Jews" the same sentiment wouldn't be?  I simply don't see it.

You don't have to be gay to think that gay people deserve equal rights. And you don't have to be a Christian to have respect for those people who are.

For me to deny the right of someone else to believe in what they choose would be for them to deny my right to believe in what I choose.

That's not to say it's easy.  There will always be friction between differently held sets of beliefs - but to seek to demonise or ridicule either side not only shows a huge lack of respect it is also the slowest and hardest path towards progress.