milkyrain

here is an article i wrote about the solar system let me know what you think . The History of the Solar System. The cloud of gas surrounding the dull yellow star cooled. From the remains everything in our solar system was born, the last skin of the dead star made our blood, all of the material that makes our skin and faces, our hearts and brains were all first made together in a colourful ball of light in the sky. The exploded debris circled the left over star like water circling a drain, and eventually the lumpiness of the matter meant that it fell together again making different balls at different distances, some so heavy that the matter near them began to circle them too, and from this the planets and their moons formed. Far away from the Sun's warmth lay an icy edge to the solar system where one hundred thousand million comets grew. Much further in than this, just outside of the orbit of Neptune, another cloud of comets formed, debris of the explosion that were too small to form a planet. The largest of these we call Pluto. Five times less massive than our Moon and covered in frozen methane Pluto spins with its twin planet Charon crossing the orbit of Neptune every few hundred years. The furthest properly formed planet, Neptune, circles forty times closer to the Sun than the first belt of comets. Neptune is beautifully dark blue with huge dark methane storms and small white clouds. A number of large moons and millions of small ones circle it's cold, gaseous body. The small moons make a ring around it's centre whilst one of it's larger moons, Triton, explodes with volcanic activity producing gases similar to those that used to dominate Earth, possibly even water. Uranus, the next planet in, is the same deep blue as Neptune and has the same type of ring around it, but it has been knocked sideways from all of the other planets. It's violent past is evident from this and one of it's moons, Miranda, which shows deep scars from being blown apart and fused back together again. Further in still is a yellow planet with a million colourful small moons circling around it in hundreds of separate rings. Saturn's outermost moon, Iapetus, is split into two colours, one side is as black as tar and the other as white as snow. It too once had a ring like Saturn's but the rocks fell in making a huge range of mountains around the centre. Another of Saturn's moons, Titan, is shrouded in bright orange clouds which contain within them the molecules needed to make life. Like Neptune's Triton, Titan contains the same materials Earth used to have but it is cold and its ocean of methane and water is frozen and slushy. The next closest planet to the Sun is also the largest. Had Jupiter been any larger it may have lit up to become a star too, but it is just a bit too small and instead it is a stormy, electronic, red ball of gas containing a cyclone three times the size of Earth that spins around it at tremendous speeds. Europa, one of it's moons has an ocean of liquid water separating it's rocky core and icy surface. In this ocean heat rises like in the underwater volcanoes on Earth, icebergs float above. On another moon, Io, volcanoes explode making clouds of sodium above a rocky surface of yellow sulphur. Ganymede is the largest moon in the solar system, and is bigger even than Mercury, it is a huge ball of ice and shines like a giant crystal in the sky. Jupiter is so large that it pulled apart the planet which was to form next leaving a scattering of boulders made of iron and semi-precious stones. The asteroids alone are not massive enough to become spherical. A sphere is formed because everything falls to the centre just like apples falling down to Earth instead of up to the sky. On the other side of the world the apples also fall to the ground. Here people walk with their feet nearer us than their heads and the see the moon and the Sun upside down from the way we see. There is no up and down only the pull of gravity, things always fall towards the heaviest object. Planets and moons are so large that everything falls inwards at the same rate and a sphere is formed, any dents will even out as matter falls in to fill the gap. But the asteroids are too small to pull everything inwards and so are dented and distorted. Two of these asteroids, Phobos and Deimos fell into the valley of space made by Mars and orbit it as moons. Mars is made of the same thing that makes our blood, and because of this it is red. The plains of Mars make a sandy desert blown by a carbon dioxide wind, just like the Earth used to be. It was warmed by volcanoes, some three times taller than Mt Everest, but like the Earth it is cold at the poles and dry ice snows down. On the other side of the Earth from Mars lies Venus. Venus is incredibly bright as it is covered in a thick layer of white clouds made from greenhouse gases and gaseous sulphuric acid. This insulates the planet so that the volcanic and cratered surface exists at the same temperature throughout the day and across it's whole surface. Closest to the Sun lies Mercury, a rocky planet covered with dust, lava flows, and a surface as cratered as the moon.

Einstein and Relativity. St. Augustine thought that time did not exist before the beginning of the world and Einstein confirmed this one hundred years ago. Time was shown to be just another dimension like the three spatial ones we experience. Time and space are entwined so time too curves under gravity when the universe does. Einstein thought about Galileo's relativity, that we did not feel the movement of the Earth because we were moving at the same speed as it. It is only a change in acceleration that can be felt and so Einstein realised that no scientific experiment could distinguish whether you were moving at a constant speed or if you were still without looking outside to see if anything else was moving. You are only moving in relation to what is around you. It is not just constant speed that can't be felt but a constant acceleration which is why it works for something which is not just travelling in a straight line. Because of this Einstein realised that the constant acceleration of gravity would be indistinguishable from any other type of acceleration. Einstein saw that gravity wasn't something in the mass which pulled directly on the object. It pulled on space itself, space was soft like a 4 dimensional blanket and anything heavy placed on it bent the blanket. Anything too close rolled into the well it made. Light would roll into it too even though it was thought by most that light had no mass. Einstein worked out that energy, invisible forces and the bright waves of light were interchangeable with mass, the particles that make up people. This meant that even light was effected by gravity and would grow colder the steeper the curve it had to fight against. Energy and mass were connected by a number that reoccurs in countless laws of the universe, the speed of light times by itself. It would take an infinite amount of energy to go over the edge and travel faster than light and so nothing ever could, and if they did they would find there was no universe to travel through. Because there is a limit to the speed that information can travel we can only ever know of the things which will have time to travel to us. We can not see past any light that will not have had time to reach us. Light can be used to break down a wall and that matter can turn into pure white energy. Energy is like a ripple in universe as one thing changes into another. Einstein realised that this meant that the shape of the universe depended on what it contained. There was perhaps no such thing as flatness and the shortest distance between two objects could often become a curve. Everything had to role around the bumpy currents of spacetime and nothing could accelerate faster than gravity allowed, no matter what their mass. Feathers fell on the moon at the same rate as kilos of lead. There were black holes as heavy as 250 million Suns and some as small as an atom. The shape of space could make time stand still in some places and go slower and faster in others. According to relativity the universe exists in this way with time laid out like the dimensions of space all inside a 4 dimensional sphere. The concept we have of presence is merely an illusion. Einstein discovered that if the universe had too much mass close together then it wouldn't balance out like in Newton's universe and space could curve so much that it would bend back in on itself until it got so small that it disappeared. As space curves so does time and some heavy universes could curve in on themselves completely. When people looked at all the different possible universe's a man called Gödel found a possibility where time looped at every point, wherever you went time take you back to when you begun. Knowing that the universe was pulled into shape by what lay inside it people could measure just how curved our universe was. A giant triangle was measured in the sky and the angles added up to a number greater than 180 degrees, the universe had curved in on itself. As space curves and we accelerate around it space and time distort themselves so that the speed of light remains the same and so we measure lengths as being shorter as we accelerate past them as it takes us less time to get from one end to the other. Time is measured differently if you are in a space ship compared to someone on the Earth. Seconds take longer to tick by the stronger the gravitational force you are in, or the faster you go. - a article on relativity from my website

Quantum Mechanics The nature of light as understood in terms of the Maxwell's electromagnetic wave theory of light says that light is made of an electric and a magnetic force moving perpendicularly to each other towards the lights direction. The force fields oscillate periodically and are detected as waves. This can be shown by the pattern of interference shown when light passes through two or more slits. The double slit experiment, used to show interference in waves, can be performed on one photon, one packet of light, at a time. You would expect that no interference pattern be seen as unlike a wave one photon must travel through either one slit or the other and have nothing to interfere with. However this experiment has been performed numerous times, and after letting a stream of photons through one at a time the random dots on the screen soon revel an interference pattern. This implies that the photons split when going through the two slits and reforms to be detected as one photon on the screen. The photons can also be measured by placing a detector on each slit measuring which one it goes through, when this is done an interference pattern is not formed. The light beam behaves as a particle when equipment that tests for particles is used, and as a wave when a wave is being tested for. The question then rose of how the quanta knew what number of tunnels to pass through when the particle detector is placed at the other side of the door. The fact that everything had the potential to act like waves of energy and particles of mass was explained by Einstein. It was shown that electrons can act like particles when they collide but when they orbit a nucleus they travel as a wave, always a whole number of waves from the nucleus. It can only travel at a completed wavelength and so it has a non zero minimum energy. If the electron is given more it will try to reach it's lowest state emitting any access energy as photons. Measuring which slit the photon travels through is measuring it's position and measuring the interference pattern is a measurement of it's wavelength from which you can work out it's velocity, that is it's direction and speed. Because it can not be measured as both a wave and a particle at the same time properties of both can not be measured simultaneously, they are non-commuting. The more accurately you can measure the position then the less accurately you can measure the velocity and the same is true the other way around. The uncertainty could never be less than a certain number worked out by Heisenberg. Quantum mechanics can not predict what something will do in the future, it can only give a probability. Like throwing dice it can not be known what the outcome will be all we can determine are the probabilities of the quanta having each position and velocity which is described by something called the wave function which we can predict over time. Previous to this people had thought that the future was predictable. Laplace suggested that if we knew the positions and velocities of all of the atoms in the universe then we could predict it's whole future and work out it's whole past but the Heisenberg uncertainty principle showed that it is a fundamental law of the universe that you can not know both these things. It is not just the limitation of our knowledge, it simply can't be done. Two photons can be connected together and separated to the other side of the world and still the measurement of one will change the state of the other instantly irrelevant of location. If two quanta were formed which had to propagate at right angles to each other in all planes then measuring one would determine that the other was 90 degrees from it. The property did not exist until it was measured and yet simultaneously the other quanta changed to correspond with the measured result. This happened even if they were so far apart that not even light could travel between them, no message could be sent. Quantum physics explains this by stating that there is a non-locality whereby the photon knows how to behave how ever far away the apparatus is from it, location is irrelevant. However this knowledge can not be sent as a message as it can be so far away that not even light, the fastest possible thing, could travel there in time. This implies instantaneous communication 'Spooky action at a distance' Einstein called it. The Copenhagen theory accepts these aspects of quantum physics as merely factual information about the universe that we have discovered, this is in contrast to Einstein's view which was that the consequences of quantum physics shows an incompleteness of the theory. In 1935 as part of an on going debate with Bohr, who advocated the Copenhagen theory Einstein and his colleagues Podolski and Rosen presented a paper (known as EPR) that claimed locality must be preserved. The EPR paper stated that quantum physics has an incompleteness which can be explained by 'hidden variables'. An experiment can be set up whereby the energy states of electrons are altered so that there is a release of photons. It has been found that in certain atoms the photons released are always done so at perpendicular angles. This can be measured in the x, y and z planes, and so measuring the polarisation in plane x of photon A determines that the same result in photon B would be perpendicular to this. This is country to the above statement that two non-commuting variables can not be known simultaneously. If this is true then there need not be a theory of non-locality, the photons simply have fixed but opposite polarities when they leave the electron. Bell's theory explains the probabilities of specific measurements of the polarities in the x, y and z planes of two photons if Einstein was correct. In practice the probabilities recorded did not agree with this inequality, assuming the laws of logic hold, that special relativity holds, and that locality holds there is no explanation for the recorded results. The assumption that must be wrong is locality, our idea of space, and therefore only quantum physics can account for the fact that the probability is different - the measure of x in Photon A disturbs the measurement of y in Photon B. The random as apposed to deterministic nature of the photons, and the idea that it is only in measuring a feature that the feature exists is troubling to the classically held view of reality as holding fundamentally predictable and logically explainable empirical and a priori properties. Perhaps space is an illusion, or perhaps the illusion is time. If this experiment is carried out with a time delay on the photon that is measured then it must affect the other photon even though it should have already chosen what to be. The message is sent backwards in time. Another idea is that perhaps it is not random whether or not we view an ordinary quanta as a wave or a particle. Perhaps every time this decision has to be made the universe branches off into two, in one world it is a wave and in another a particle. The new parallel world and an infinite amount of others are all contained inside something else. It seems that what is random is not what the quanta does but in which world your consciousness lands in. Some believe that this means that the observation which defines the quanta's existence must be by a conscious observer. This would mean that the universe would not exist if we were not here to observe it and would lead to the question of how we could have then evolved in it. just a little introduction