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in 1983, stephen hawking and james hartle proposed a new model of the universe. it proposes a no-boundary condition where the universe is self contatined but finite, just like the surface of the earth. imagine taking a stroll along the equator, there would never be a precipice for you to fall ova (therefore no boundaries/edges), but u would eventually come back to where u started ur stroll (therefore finite).
in their model they eliminated the distinction between time and space ... how can i put it down in words ......
i thik i'll just use the concave up parabola to represent this interesting model of theirs ... once u travel back to the place where the universe begins - the bottom of the parabola, u cannot go any furthur back coz the past does not exist (just like how at the north pole, the meaning north becomes meaningless .... i hope im making sense .....)
now, imagine a line with 45 degree slope, on a graph with the verticle axis representing time and the horizonetal distance in space. this slope shows the 'world line' of a photon (i dono y it has to b a photon though) travelling at the speed of light. (...... all this refers to spacetime - 4-dimentional )In the early stage of the universe, the space is extremely dense ( not es dense as a singularity, maybe just above that, so that the laws of physics dont break down). according to the uncertainty principle which causes the smearing effect of electrons in an atom, the same happens to our early universe, therefore causing the slope to ripple (therefore no longer straight) this fluctuation of the photon eliminates the distinct characteristic between space and time. (coz of some mathematical implications .... something about the square of the hypenuse no longer being -ive) so now instead of space-time, we hvae 4-dimentioanl space. therefore in the early stage of the universe, time is just another spatialised dimention with no boundary or edge, jsut rounded off like how the universe is (it corresponds to the bottom bit of the concave up parabola). only later does time receive its distinction. anyways back to the parabola ... so if things were rounded off like that then the universe would be like .. self contained...... so there r no single pt for singularity ....
i think hawking also made a very famous remark on this model, he said something like 'insted of picutring the universe being created, it would just Be.'
...... god it feels like iv just sat for one of my yearly exams ..... i think i went off the topic alittle, hope i havent bored anyone whos actually patient enough to get to this line .... (or maybe noone has ....)
i guess my pt is that there is a strong oppostion coming from the hawking team proposing against the need for a singularity at the big bang ..... quite ironic to think that it was himself that came up with the singularity theory in the first place ....
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