Planet Earth is now approximately 4.5 billion years old. It was formed as part of our Solar System consisting of the Sun and 9 planets (some say only 8 planets, as Pluto was demoted). As our planet needs the Sun which supplies all it’s energy in one form or another, when the Sun begins to die, then it’s curtains for Earth. Of course this is not expected to happen for at least another 4.5 billion years. So why worry?
Well, no need to at the moment, but with man’s hunger for exploration (and I really believe that this hunger is one of the driving forces behind the animal called Homo Sapiens and if it couldn’t be satisfied we would atrophy) we will explore the Solar System and beyond. Then we will colonise and live on new planets orbiting strange new stars (of course it is to be hoped that we will have been able to bring our intelligent and emotional aspects into line so we won’t butcher other peoples or races in order to do this).
But the real interesting question is how are we going to get there? Distances in space are so vast they are practically incomprehensible. Four and a half light years to our nearest star Alpha Centauri. That means it takes light four and a half years to reach us from that star, our nearest stellar neighbour. Light travels at approximately 186,000 miles per second. That places Alpha Centauri about 26 million million miles away. That number is simply not graspable to the human mind; it’s just enormous. But travelling at the speed of our Voyager spacecraft (38,000 miles/hour) it would take about 80,000 years to get there. Even if we were able to build spacecraft which could go faster than this it would take many human lifetimes to reach our nearest star. And once we got there, it is almost certain that we would find no suitable planets for us to colonise. In fact we would have to go much further into space to find suitable habitats.
So conventional spacecraft don’t seem to be a viable option. What else then? What about a matter/antimatter engine? Antimatter is in very short supply and it’s not easy to make (besides it costs about $25 billion per gram). It is mainly used in big physics experiments using machines which collide particles at nearly the speed of light in order to study them. The property of antimatter which interests us is the fact that if you collide a particle of matter with a similar particle of antimatter they convert their total mass into energy with close to 100% efficiency. Such a matter/antimatter engine could bring us to more than 90% of the speed of light which is a considerable improvement. It means we could probably arrive at the Alpha Centauri star system (three stars, in fact) in less than 5 years. But we don’t want to go there! We need to find a solar system with an earth like planet. Current estimates say such a system may be as close as 20 light years away. So that means a trip of about 22 years. That’s a long time travelling in space in close proximity with your travelling companions. Would the human psyche be up to such a journey?
So we need something faster and now we go into the realms of Star Trek. What about a warp engine? Now that would be some invention, but in theory possible. As Einstein’s relativity theory says nothing can travel faster than the speed of light, then there is no way a spacecraft made of matter can break the light barrier. So we have to somehow reduce the distances. Warping space is one way to do this. Don’t ask me how this can be done as nobody knows (even if it’s actually possible), but let’s assume for a moment that it is feasible. In fact if it’s not possible, it doesn’t hold out much hope for interstellar exploration in the short term. We’re just going to have to go the long way round: hibernation techniques, or building huge craft capable of carrying thousands of people and taking many human generations to reach the stars. But let’s not get into that now.
According to general relativity (Einstein’s gravity theory) two points incredibly far away in real space can be brought very close together by warping the space between them. Actually by warping the spacetime between them, but let’s not complicate matters. If we can warp the space by creating what is termed a wormhole between the two distant points, we can travel practically instantly between them. Such technology, while nowhere within our grasp today, may not be so far off. I would estimate less than a thousand years. Which is quite annoying really, as I expect to be long dead by then. Ah well, you can’t have it every which way.
Sunday, February 21, 2010
Thursday, February 11, 2010
Infinity
Watching a recent BBC Horizon programme on infinity, put me in mind of when I was a child and I used to think about infinity a lot. I remember believing that when you went to heaven it was forever. So I'd lie in the field and look up at the infinite depths of the blue sky above and think about being in heaven. This was pleasant for a while as I'd imagine myself sitting up there and it was millions of years in the future and I'm still there. Then it would be millions more years and I'd still be there. And then I'd be overcome with a strange feeling in the pit of my stomach, a sort of queasy sensation which wasn't particularly nice at all. I'd stop thinking about it and then start all over again.
So is infinity real or just a figment of our imagination? Like we can imagine things that aren't real, like unicorns.
But infinity must be real, mustn't it? I mean, just start counting: 1, 2, 3,... infinity. The problem is that it doesn't stop at infinity (or the largest number you can think of). You can simply add 1 more.
Some guy on the Horizon programme said that he wasn't comfortable with infinity and postulated that there was a largest number which when you added 1 to it equalled 0. So you were back where you started. Like starting at a point on the earth's surface and walking in a straight line until you circumnavigated the globe and arrived back where you began. That was an interesting concept but I don't believe it.
But the concept of infinity leads to strange results. Take the apparently simple question of which is bigger, the set of natural numbers (1, 2, 3,...) or the set of even numbers (2, 4, 6,...). The obvious answer is the set of natural numbers. But that is incorrect. They are both the same size. How can this be so? Well, if you believe Georg Cantor, a German mathematician (1845 - 1918) who developed a branch of mathematics called set theory, you have to deal with infinity as a one-to-one correspondence. So taking the two sets of numbers you match 1 (in the first set of natural numbers) with 2 (in the second set of even numbers). Then you match 2 with 4, 3 with 6 and so on. Now for every number in the set of natural numbers you can match it with a number in the even set. Just double it. So the two sets are the same as you can always find an even number to correspond with a natural number.
This leads to all sorts of weirdness with infinity. Take Hilbert's hotel (he was another mathematician from the same era). This is a hotel with an infinity of rooms. You arrive at the hotel and ask for a room only to be told that the hotel is full. But hold on, the manager comes to your rescue and moves all the guests. He puts the guest in Room 1 into Room 2, the guest in Room 2 into Room 3 and so on. Now Room 1 is empty and you get your accommodation after all.
Something even stranger: if we live in an infinite universe, then there must be an infinite number of identical copies of you and indeed everybody else. Now that's a hard one to get your head around.
Look at it this way: let's assume you have many billiard balls and each ball can have only one of 2 colours. That means there are only 16 different ways these balls can be grouped together on a billiard table in a square pattern of 4 balls each. So no matter what combination of 4 balls you choose to place next on the table, it has to be a copy of one of the already existing 16 patterns. Similarly in an infinite universe there are only a certain number of atoms and only a finite way these can be put together. Therefore there has to exist copies of you and everybody else somewhere in the infinite universe. Now that's scary.
Of course, the universe may not be infinite. Besides, the concept of infinity may only exist in our minds.
Fergal
www.uglythump.ie
So is infinity real or just a figment of our imagination? Like we can imagine things that aren't real, like unicorns.
But infinity must be real, mustn't it? I mean, just start counting: 1, 2, 3,... infinity. The problem is that it doesn't stop at infinity (or the largest number you can think of). You can simply add 1 more.
Some guy on the Horizon programme said that he wasn't comfortable with infinity and postulated that there was a largest number which when you added 1 to it equalled 0. So you were back where you started. Like starting at a point on the earth's surface and walking in a straight line until you circumnavigated the globe and arrived back where you began. That was an interesting concept but I don't believe it.
But the concept of infinity leads to strange results. Take the apparently simple question of which is bigger, the set of natural numbers (1, 2, 3,...) or the set of even numbers (2, 4, 6,...). The obvious answer is the set of natural numbers. But that is incorrect. They are both the same size. How can this be so? Well, if you believe Georg Cantor, a German mathematician (1845 - 1918) who developed a branch of mathematics called set theory, you have to deal with infinity as a one-to-one correspondence. So taking the two sets of numbers you match 1 (in the first set of natural numbers) with 2 (in the second set of even numbers). Then you match 2 with 4, 3 with 6 and so on. Now for every number in the set of natural numbers you can match it with a number in the even set. Just double it. So the two sets are the same as you can always find an even number to correspond with a natural number.
This leads to all sorts of weirdness with infinity. Take Hilbert's hotel (he was another mathematician from the same era). This is a hotel with an infinity of rooms. You arrive at the hotel and ask for a room only to be told that the hotel is full. But hold on, the manager comes to your rescue and moves all the guests. He puts the guest in Room 1 into Room 2, the guest in Room 2 into Room 3 and so on. Now Room 1 is empty and you get your accommodation after all.
Something even stranger: if we live in an infinite universe, then there must be an infinite number of identical copies of you and indeed everybody else. Now that's a hard one to get your head around.
Look at it this way: let's assume you have many billiard balls and each ball can have only one of 2 colours. That means there are only 16 different ways these balls can be grouped together on a billiard table in a square pattern of 4 balls each. So no matter what combination of 4 balls you choose to place next on the table, it has to be a copy of one of the already existing 16 patterns. Similarly in an infinite universe there are only a certain number of atoms and only a finite way these can be put together. Therefore there has to exist copies of you and everybody else somewhere in the infinite universe. Now that's scary.
Of course, the universe may not be infinite. Besides, the concept of infinity may only exist in our minds.
Fergal
www.uglythump.ie
Monday, February 8, 2010
Why so uptight about the ten commandments?
Channel 4 are broadcasting "The Bible: A History" at the moment. I watched some of Episode 3 which had Ann Widdecombe (English Catholic and conservative MP) talking about the ten commandments. I found her point of view very interesting and very positive. She basically was saying that the ten commandments were a good thing and it was a pity they weren't followed more closely in today's society.
What surprised me during the programme was the explosive anger displayed by both Stephen Fry and Chistopher Hitchens, both atheists. For the record I am agnostic.
Stephen Fry when asked by Ann Widdecombe what was wrong with the commandments, like "honour your father and mother", "don't kill", he interrupted vehemently and demanded to know where was the commandment against slavery. Hold on, did I miss something? He was asked a simple question but he evaded giving an answer. I don't pretend to read his mind, but was this because he didn't want to say there was nothing wrong with them?
He also got particularly upset at the notion of commandment, "How dare you command me..." What's wrong with commanding people not to kill each other? Okay, we can get into the whole notion of killing in self defence etc. but over all we really shouldn't be killing each other. Stephen also went on to say that the commandments have suppressed, tyrannised and bullied. Suppressed who? Tyrannised who? Bullied who? The church may have done this. Kings and tyrants may have done this. But the commandments themselves did not. In fact if the church and company followed the commandments they would not have suppressed, tyrannised or bullied anybody.
Christopher Hitchens, similarly, couldn't seem to answer straight up on the ten commandments. Instead he insisted that we read the next chapters of the bible and all about the cruelty therein. He then seemed to march out of the room.
Why do these guys get so incensed by the notion of a moral code which comes out of the bible? Okay, it may not be perfect and certainly doesn't address certain modern day issues. But it seems to me that they do address the core issues. And the fact of the matter is if people followed the ten commandments today, then I doubt society would be in the mess it is. Forget about religion. Forget about God. Taking the ten commandments in isolation, they are not a bad moral code at all.
Fergal MacAlister
www.uglythump.ie
What surprised me during the programme was the explosive anger displayed by both Stephen Fry and Chistopher Hitchens, both atheists. For the record I am agnostic.
Stephen Fry when asked by Ann Widdecombe what was wrong with the commandments, like "honour your father and mother", "don't kill", he interrupted vehemently and demanded to know where was the commandment against slavery. Hold on, did I miss something? He was asked a simple question but he evaded giving an answer. I don't pretend to read his mind, but was this because he didn't want to say there was nothing wrong with them?
He also got particularly upset at the notion of commandment, "How dare you command me..." What's wrong with commanding people not to kill each other? Okay, we can get into the whole notion of killing in self defence etc. but over all we really shouldn't be killing each other. Stephen also went on to say that the commandments have suppressed, tyrannised and bullied. Suppressed who? Tyrannised who? Bullied who? The church may have done this. Kings and tyrants may have done this. But the commandments themselves did not. In fact if the church and company followed the commandments they would not have suppressed, tyrannised or bullied anybody.
Christopher Hitchens, similarly, couldn't seem to answer straight up on the ten commandments. Instead he insisted that we read the next chapters of the bible and all about the cruelty therein. He then seemed to march out of the room.
Why do these guys get so incensed by the notion of a moral code which comes out of the bible? Okay, it may not be perfect and certainly doesn't address certain modern day issues. But it seems to me that they do address the core issues. And the fact of the matter is if people followed the ten commandments today, then I doubt society would be in the mess it is. Forget about religion. Forget about God. Taking the ten commandments in isolation, they are not a bad moral code at all.
Fergal MacAlister
www.uglythump.ie
Monday, February 1, 2010
A Dog with Two Names
Today Joan and myself took the decision to end our dog's life. Although this was a sad decision, it was kindness to the dog to relieve his continued suffering. What made the decision even harder for me, was the question as to who or what gives us the right to take his life. This power which I don't want was thrust on me. I hate this god like decision over another's life. But we took it anyway.
We know something which even Timmy doesn't know. The date and time of his death. Like an execution. 9am Friday 5th February 2010. He is 12 years old. So he can have some chocolate now if he likes. He can lie on the good rug, what the hell, the hairs can be hoovered up afterwards.
But he has two names. We call him Timmy while others insist on calling him Jimmy. He doesn't mind, he answers to both.
When he was about a year old, we went on holidays and left him with my two sons to mind. Naturally, they were looking forward with great excitement to looking after this little bundle of mischief. Of course, my elder son decided to play a trick on the younger and tell him the morning of the great day he was to arrive, that Dad had called to say that Timmy wouldn't be along as somebody else would be looking after him. However, as soon as Andy saw the consternation on Dan's face, he quickly said, "But his cousin Jimmy will be coming instead".
And hence the dog with two names will die this Friday. God rest him.
We know something which even Timmy doesn't know. The date and time of his death. Like an execution. 9am Friday 5th February 2010. He is 12 years old. So he can have some chocolate now if he likes. He can lie on the good rug, what the hell, the hairs can be hoovered up afterwards.
But he has two names. We call him Timmy while others insist on calling him Jimmy. He doesn't mind, he answers to both.
When he was about a year old, we went on holidays and left him with my two sons to mind. Naturally, they were looking forward with great excitement to looking after this little bundle of mischief. Of course, my elder son decided to play a trick on the younger and tell him the morning of the great day he was to arrive, that Dad had called to say that Timmy wouldn't be along as somebody else would be looking after him. However, as soon as Andy saw the consternation on Dan's face, he quickly said, "But his cousin Jimmy will be coming instead".
And hence the dog with two names will die this Friday. God rest him.
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