The Twins Paradox 
Sunday, 27 May, 2012, 11:30 AM - Science, Not TFTD
Yes, yes, I know, this has been covered a gazillion times by every amateur, would-be physicist on the internet. I just haven't found a website that I thought explained it both clearly and properly. There's really much more going on than I think most people realise.

For those who need a reminder: the twins paradox is a scenario in special relativity. To understand the paradox you only need to know one thing: moving clocks run slower than stationary clocks.

You have two twins: A and B. A remains on Earth. B boards a spaceship and whizzes off to a distant star and then returns. A sees the clock on B's spaceship running slow, so B will be younger than A when B returns. However, everything is relative. From B's point of view it is A that has been moving and so it is A's clock that runs slower. So A should be younger on B's return - an apparent contradiction.

Some texts are content to point out that there is a clear asymmetry in the twins' behaviour. B gets accelerated and decelerated several times, whereas A does not and therefore the "paradox" is a non-starter. Others describe solutions to the paradox that ignore the accelerations and decelerations, which is a shame, because a lot of the interesting physics takes place during the accelerations and decelerations.

I'm going to explore an approximate approach, where the changes in velocity happen very quickly, but not instantaneously.

The diagram above is a space-time diagram. It shows the position in space and time for twin A and twin B. Twin B moves off to the right towards the star and also travels upwards through time. Twin A stays still, but also moves upwards through time. Twin B reaches the star and then returns home to meet A back on earth again.

14 comments ( 367 views )   |  permalink   |   ( 3.1 / 147 )

Vishvapani (a much nicer name than Simon Blomfield) - I'm ordained you know! 
Wednesday, 23 May, 2012, 08:43 AM - Science, Vishvapani
Rating 2 out of 5 (A little platitudinous)

I've just started gardening. Others are busy destroying modified plants. Some think GM could provide more efficient crops, others think it is meddling with nature.

The idea that our minds are distinct from our bodies is undermined by science. Even plants display an awareness of their environment and respond accordingly - a kind of primitive consciousness. We also consciously interact with and modify our environment, so it is difficult to see why GM crops should be any different.

One Buddhist meditation reflects that all that we are comes from nature and returns to nature. We are part of the world around us. The world is full of life and our life is part of that world. This view informs our ethical response to environmental crises in various unspecified ways.

10 comments ( 554 views )   |  permalink   |   ( 2.9 / 137 )

Right Awful Anne Atkins - Agonising Aunt and Vicar's Wife  
Friday, 27 April, 2012, 08:26 AM - Science, Atkins
Rating 5 out of 5 (Extraordinarily platitudinous)

What's the point of smell? We could easily do without it. Some things smell nice but that isn't really enough reason to keep a sense of smell.

The real reason to keep a sense of smell is because it brings back memories. Here are some things that smell nice and bring back memories.

Bakewell tart
Cut grass
Cups of tea
A young lover's sweaty, stain encrusted armpits, shirt
Brasenose College Oxford

Did I mention that I went to Oxford? To Brasenose College actually.

Jesus smelled nice when he had perfume on - and that's not at all gay by the way. It was probably some very manly perfume, like Old Spice - a bottle of which could easily pay for the world's poor and hungry.

He also smelled nice when he made 180 gallons of wine (the evidence for which was delivered in great detail yesterday, so there's no need for me to go into that). The wedding didn't even have to pay excise duty on the 180 gallons of wine.

So Jesus approves of smell, therefore a sense of smell is OK.

17 comments ( 573 views )   |  permalink   |   ( 3.1 / 169 )

Rev Rob Marshall, an Anglican Priest 
Saturday, 3 March, 2012, 08:25 AM - Life after death, Science, Marshall
Rating 3 out of 5 (Fairly platitudinous)

Two thirds of people in Wales think presumed consent for organ donation is a good idea.

It's an emotional subject. To find out whether the people of Wales are right or wrong, we must consult the Big Book of Magic Stuff. It turns out that the Big Book of Magic Stuff has quite specific instructions on slavery, holy war, something called "women" and a large number of offences that you should be put to death for. It does not have any specific instructions about organ donation. I'm therefore going to make them up and post rationalise it in an attempt to make the Big Book of Magic Stuff seem relevant to modern ethical problems.

Jesus, whom you'll recall was the visible bit of the Invisible Magic Friend, did rather a lot of healing. This suggests that healing and preventing suffering is probably a good thing. From this is turn, we can infer that donating the organs of the deceased to benefit the living might also possibly be considered to just maybe be a good thing. After all, there is an after-life, despite what Giles Fraser may say, so the bit we float around in in the before-life doesn't matter that much.

In conclusion, Christian theology unambiguously and definitively can't make up it's mind, proving once again the value, relevance and moral leadership of the modern church.

17 comments ( 496 views )   |  permalink   |   ( 3 / 114 )

Rabbi Lionel Blue 
Monday, 27 February, 2012, 08:54 AM - Be nice, Science, Rabbi Lionel Blue
Rating 3 out of 5 (Fairly platitudinous)

Good morning Justin, good morning John and good morning to you all.

I am a poor old man. My sight is poor, my legs are old and bent. The fresh faced youngsters at my college tell me science is the only tested form of knowledge. So I've read the popular science books by Dawkins and Hawking and watched every TV programme with Brian Cox in it.

My eyes are dim, I cannot see and all this science was very interesting but it didn't help me with my bus pass application. It told me about the what and the how but not the why? What's it all for? Why are we here? Why am I telling you this? Why are you listening to me telling you this? Why am I asking you why you are listening to me telling you this? It's very important that there be some external reference to define why, otherwise we might just make up our own why and think how terrible that would be.

I am just a poor old man. My legs are grey, my ears are nulled, my eyes are old, and bent. That's why Jewish mysticism helps. In the beginning there was Nothing. It likes to spell itself with a capital N due to it being the only nothing around at the time. Then, out of nothing, came the spark of divine thingness, which explains how we came about and why.

My legs are old and bend, my ears are grizzled. Jewish mysticism may be a myth but it's a true myth and is much more useful when filling in my bus pass application. And so we see that helping the poor, spreading laughter and just generally being nice puts Humpty Dumpty together again.

I'm just a poor old man, my eyes are poor, my nose is knackered.

10 comments ( 541 views )   |  permalink   |   ( 3.1 / 172 )

Theories about Faster than Light Neutrinos 
Thursday, 23 February, 2012, 10:10 AM - Science, Not TFTD
There was a rash of papers offering explanations for the faster than light neutrinos coming from CERN a few months back: variations on relativity, particles tunnelling through extra dimensions, multiple time dimensions, were just a few.

It isn't confirmed, but it looks like the solution to the mystery may have been found. The timing discrepancy was due to... a loose cable.

When they tightened the cable properly, the faster than light neutrinos disappeared.

The nice thing about science is that it fixes its mistakes. Now if this was theology...
7 comments ( 335 views )   |  permalink   |   ( 3.1 / 140 )

Soberingly Reverend Tom Butler, ex-Lord Bishop of Southwark  
Friday, 17 February, 2012, 08:32 AM - Science, Theology, Butler
Rating 5 out of 5 (Extraordinarily platitudinous)

Quantum Physhics ish all a bit of a myshtery. (hic!) I mean, nobody really undershtands any of it, do they? Even the people who undershstand it (hic!) shay they don't undershtand it. Thingsh can be in two plaishes at onesh and be both a partishiple and a wave at the shame time. (hic!) Dushn't make any shensh doesh it? It'sh all very confusing. (hic!)

Thish is exactly the shame ash Chrishtian theology. It'sh all very confusing too and nobody undershtands it either. The Invishible Magic Friend (hic!) can be all over the place and there can be three of him and only one of him at the shame time. It'sh all very mishterious. (hic!)

Jusht like Quantum Physhics, Chrishtian theology has proved to be amazingly useful (hic!), at least to Chrishtian theologians. They've written loadsh and loadsh of booksh about how mishterious it ish and how you'll never undershtand it. Quantum Physhics and Chrishtian theology have both been teshted to remarkable degreesh of (hic!) accurashy. Chrishtian theology is now mishterious to over 13 deshimal plashesh, making it the most baffling and incompre-hen-shible bogledegook ever invented by people with nothing better to do.

Yet the Church Fathersh (there were no Church Mothersh - Shaint Paul wouldn't allow it) invented all this obshcure, shelf contradictory drivel, thoushands of yearsh before shcientists got around to it. Just goesh to shoe, doeshn't it? (hic!)

I wonder if it'll make a bit more shensh after a shmall sherry. (hic!)

15 comments ( 607 views )   |  permalink   |   ( 3 / 227 )

Rev Dr Michael Banner, Dean and Fellow of Trinity College, Cambridge  
Wednesday, 15 February, 2012, 08:49 AM - Science, Banner
Rating 4 out of 5 (Highly platitudinous)

Yesterday was Valentine's day: a day of romance, true love and conspicuous affection.

God I can't stand Valentine's day. It makes me want to vomit on all those roses and pink champagnes and god awful cuddly teddy bears. I loathe and despise cuddly teddy bears. A curse upon all cuddly teddy bears.

Which brings me neatly onto the subject of science-and-magic. No one in the field of science-and-magic knows what love is. This just goes to show how rubbish science-and-magic is. I know rather a lot about science-and-magic people. The college that I'm dean of has rather a lot of them and I can tell you that science-and-magic people don't know half as much about love as Saint Paul did.

Which brings me neatly onto Saint Paul. He knew a lot more about love than science-and-magic people do. If you want to know something about love, the person to consult is Saint Paul and not science-and-magic people. Saint Paul wrote a famous bit about love. This is often read out at weddings with a horrible sentimental voice, full of emotion. This is all wrong. Saint Paul should always be read in a cross, angry, brutal, annoyed, bitter, teddy bear crushing way.

If there is one thing you can be absolutely sure of, it's that Saint Paul, even when writing about love, absolutely hated teddy bears - teddy bears and women, teddy bears and women and homosexuals, teddy bears and women and homosexuals and just about everybody, but mainly teddy bears.

19 comments ( 685 views )   |  permalink   |   ( 3.1 / 141 )

Rev Dr. (hon. Kingston) Dr. (hon. St. Andrews) Joel Edwards, International Director of Micah Challenge, Council Member of the Tony Blair Faith Foundation  
Wednesday, 1 February, 2012, 08:22 AM - Science, Edwards
Rating 3 out of 5 (Fairly platitudinous)

Me and my fellow 4-star generals at Micah Challenge have just finished an intensive strategic planning session about our worldwide, social networking communications infrastructure. With the help of our in-house telecommunications expertise I've learned one really important lesson: this interweb thingy is really big. And it's not just technological wizards like me who are tweeting and doing stuff on Facebook, people in Africa are doing it too.

There are all sorts of stories about good and bad things that happen to people because of Twitter, more than enough to fill up a few minutes with background anecdotes that don't really form any sort of coherent message.

What's really important though is not to make the medium more sacred than the message. This much is always true: it's what people say that is important. A truth remains true, no matter who it is who says it. That's why we Christians completely ignore the fact that it was the visible bit of the Invisible Magic Friend who said all those various things that he said. The fact that he was the creator of the universe, died and rose from the dead isn't something that we particularly like to emphasise. For Christians, it is always the message and never the medium that is important.

3 comments ( 372 views )   |  permalink   |   ( 2.9 / 147 )

Rev Dr Dr Prof David Wilkinson, Principal of St John's College Durham 
Monday, 16 January, 2012, 08:59 AM - Science, Wilkinson
Rating 4 out of 5 (Highly platitudinous)

Happy Blue Monday everyone!

But I know that well educated Radio 4 listeners don't believe in pseudo-scientific nonsense like that. How about some astronomy on the telly. Isn't the universe just amazing? It's so big. Do you know who I think of when I see how big the universe is? Go on, guess. No, you'll never get it, it's the Invisible Magic Friend!

Science-and-faith both think the universe is amazing. A 3,000 year old poet agrees with me. "Oh, everything is sooooo BIG. Thank you, thank you, Invisible Magic Friend, for making all this just for me!"

Christians, with their hearsay evidence written down 30 years after the totally amazing resurrection, are just like astronomers. Science-and-faith are always saying how big it all is. Lovell called it "immensity", with is a bigger word for "big" and so makes it sound as if I'm saying something different and not just constantly repeating myself. He mentioned the Invisible Magic Friend too which further legitimises science-and-faith.

Science-and-faith can't answer everything of course, but still science-and-faith both say everything is very, very, very big. This makes science-and-faith very exciting as both agree about the overall bigness of it all. So I'll be cheering myself up by looking at some stars, confident that science-and-faith both say how very big it all is.

Did I mention that science-and-faith say how bit big it all is?

9 comments ( 621 views )   |  permalink   |   ( 3.1 / 173 )

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