Monday, 17 March 2014

The Discovery of Gravitational Waves from the Origin of the Universe

Today's discovery of gravitational waves from the origin of the universe is the most important discovery in science since that of DNA.  I'll try explain why.  But first, I have to admit that I am not an expert physicist.  If you want the technical background go to someone who really knows what is going on, such as Sean Carroll - I hope Sean writes a book on this, as his ability to explain such complex ideas is exceptional.  However, I'll try and give some idea.

Gravity curves space and time, as revealed by Einstein's work on General Relativity.  The reason why gravity pulls and diverts objects is because of this curvature.  Newton said that unless acted on by a force objects will move in straight lines.  Objects in a gravitational field move in the equivalent of straight lines in curvy space - these lines are called 'geodesics'.  Think of the surface of the Earth - the most direct route between two points at different longitudes away from the equator is not a straight line, but a curve called a 'great circle'.  'Great circles' are geodesics.  Following these 'curvy straight lines' is why objects are diverted by gravity.

As well as describing this curvature of space, Einstein also showed that changes in gravity travel at the speed of light, not instantly.  If the Sun vanished, it would take 8 minutes for the Earth to start to leave orbit, for example.

If you have curvature and that curvature can change, and the change has a speed limit, then you can get waves.  Suppose the gravity of the Sun could be turned on and off.  If this happened then pulses of gravity would travel out from the Sun's position.  If you have two objects orbiting each other, the constant change in position of the sources of gravity results in waves.

We know that gravitational waves exist because waves carry away energy and we can predict how quickly this will happen.  When the objects orbiting each other are very dense indeed, like neutron stars, then they will lose a lot of gravitational energy as waves, and their orbits will decay, and we have seen this happen.

Gravitational waves in the cosmic microwave background are such an amazing discovery because the cosmic microwave background is a microscope.  The microwave background is the light released when the universe first became transparent, when electrons stopped flying around and joined up with atomic nuclei.  This happened about 379,000 years after the origin of the universe.  The microwave background is extremely smooth, which is strange because the expansion of the universe is so fast that widely separated areas of the background can never have come into contact, to smooth out any differences.  So why is it so smooth?  One answer is inflation - the idea that the region of the universe that we can see started off extremely small and so was in contact, and then expanded incredibly fast, smoothing out any differences.  This expansion was so great that tiny quantum fluctuations became big enough to create the unevenness needed to allow gravity to collect gas together to build galaxies. Subtle fluctuations in the microwave background reveal what went on at a quantum scale.   So, gravitational wave effects in the microwave background show us ripples in gravity at a quantum scale, and the only way we can think of that these ripples have become big enough for us to see is if the ripples were blown up enormously because of inflation.

The cosmic microwaves take us back to hundreds of thousands of years after the origin.  We can see no further back because before that the universe wasn't transparent to light.  But, just about everything is transparent to gravity and gravitational waves.  When we see the gravitational waves we are looking back to the instant when our universe began, perhaps around the Planck time: 10-44 seconds - probably the shortest time that makes sense in our universe.  This not only confirms the idea of inflation, but it should allow us to get some idea of what happened at the very beginning of the timeline of our universe.

Thursday, 6 March 2014

The case for religious same-sex marriage

I'm not one of those who say that religion cannot do good.  In the UK there is a history of churches working to help the poor and oppressed, forming and supporting communities that were of benefit to those included.  But now mainstream faiths are stuck in a reactionary rut when it comes to equality, and their resistance to moral progress results in real suffering, suffering that can and should be avoided.

The matter of equality I am talking about here is homosexuality: sexual attraction and love between two consenting adults of the same sex.

Love and sexuality is a core part of the lives of most people.  Their romantic and sexual relationships help define who they are and form an important way that they bond with others in society.   Rejection of the validity of same-sex relationships is a strong factor in excluding people from participating in the rituals and institutions that, for most people, help them to be accepted as full and equal members of society.

The refusal to allow same-sex religious marriage denies many people the right to fully engage with their religious beliefs.  Some may share the belief that the appropriate place for sexual activity is between loving couples within marriage, but the denial of marriage for such people forces them to choose between celibacy and what they consider to be sinful fornication - a choice that heterosexuals don't have to make.  And so, homosexual believers are not only labelled as sexually disabled by their religions but also told that the only sexual relationships they could ever have is sinful.

Just imagine what this can do to youngsters.  Those entering the confusing time of puberty and with their first feelings of love and desire are being told by their religious culture that they are lesser people, that they haven't grown up fully in the way that God wants, that their loves can never be blessed, that their sexuality is forever sinful.  This can do great psychological harm both directly and indirectly, because being labelled as inferior by their culture makes such youngsters easy targets for bullies.  Bullying of homosexual youngsters happens on an epidemic scale in the UK, and associated with that bully are both depression and suicides.  Religions should not be providing the basis for bullying and misery of youngsters.  They should be preaching virtues, the virtues of love and equality, and they should be preaching against prejudice with all their power.

Religions can claim the inferiority of same-sex relationships in many ways.  One of those is naturalness, and yet homosexuality is widespread in nature, just like heterosexuality.  But then so is killing and suffering.  Naturalness should never be a criterion for what is good, and moral.  Another way is based on Bible texts, but that has no solid foundation as modern Christianity rejects much that is in the Bible as outdated and irrelevant.  Yet another way is to point out that homosexuality cannot give rise to children, and yet there are no fertility tests necessary for heterosexual weddings, and many couples are married when their is no possibility of children being produced.  Same-sex couples are said by some to be inappropriate situations for children to be raised, even if acquired by adoption.  The evidence is against this, but, anyway, the question of adoption is not relevant to the question of marriage.

Christians should consider the words of Jesus: "Let the little children come to me, and do not hinder them, for the kingdom of God belongs to such as these."  Don't hold back youngsters from Jesus (or Mohammed, or the Buddha) because of who they will love and desire.  Let them know that they are fully loved in all respects, and the Church will, if they want it, provide the same foundation for their loving sexual relationships as it does for those who love the opposite sex.  

In the play "8", a dramatisation of the fight for equality against California's Proposition 8, a mother points out that little girls don't dream of civil partnerships.  They don't - they dream of marriage, with all its ceremony and its acceptance.  Let their dreams not be in vain.  Let couples who love each other share fully in your culture whatever that culture may be.  

Wednesday, 5 March 2014

Praising Panti - rejecting all LGBT bigotry.

How did I not know about the wonderful Panti Bliss? His/her attack against prejudice that has got so many in Ireland worked up is something I fully agree with, and has made me realise I am being too tolerant. 

Rejection of same sex marriage is, of course, not on the same scale as violence and imprisonment of LGBT people, but it's still both wrong and harmful - it's still homophobia.

If a preacher refused to marry a mixed-race couple there would be no hesitation in calling that preacher racist, and not just some tradition-respecting eccentric.

Religious rejection of same-sex marriage is homophobic, and it does tremendous harm because it institutionalises prejudice. Imagine being queer and raised in even a mildly religious family belonging to a faith that says that your future loves are fundamentally unequal, and can never be celebrated in the same way as the loves of others. This is a form of bullying in the supposed name of morality.

I have religious friends who aren't comfortable with religious same-sex weddings. I ask those friends how they can maintain that position considering the message of moral inferiority they are sending to youngsters - telling those youngsters that their community rejects them, that they were born morally flawed.

To those friends: I know you are better than that. Please help support equality for all.