[battybat]

I see from Simon Singh's recently published book - Big Bang, that the latest estimated age of the Universe (back to the Big Bang) is approx. 13 to 14 billion years. There seems to be a consensus, from looking at the more credible science sites on the internet, that the furthest detected galaxies are over 10 billion light years away from us. Assuming we can look as far in the opposite direction, this means that we can detect at least two galaxies which are 20 billion light years apart. Moreover, they were this distance apart 10 billion years ago (because of the time their light took to reach us), which means that, assuming everything was in the same place at the Big Bang, they only had 4 billion years to get that far apart. I would think that this would be impossible, as one or both of the galaxies would have to travel at several times the speed of light for billions of years for this to happen.

This seems, on the face of it, to be a serious flaw in the Big Bang theory, but maybe I'm I missing some obvious explanation. Can anyone enlighten me?

Battybat

[AntonioLao]

Originally Posted by battybat I would think that this would be impossible, as one or both of the galaxies would have to travel at several times the speed of light for billions of years for this to happen.

This is one of the misconceptions of what is really moving when we say that the universe is expanding (see March 2005 issue of Scientific American for all the other misconceptions).

Globally speaking, the galaxies are really not moving away from each other at high radial velocities. Locally, there can be varities of motions between galaxies,which led to some collisions of galaxies and that one of the lingering cosmological mysteries is why do galaxies formed clusters and superclusters?

It is space itself that is expanding and the speed of the expansion is greater than the speed of light the farther away the galaxies are from each other (these superluminal speeds have been detected). This seems to imply that the size of the universe is larger than the size of its visible part.

[battybat]

Originally Posted by AntonioLao Globally speaking, the galaxies are really not moving away from each other at high radial velocities. Locally, there can be varities of motions between galaxies,which led to some collisions of galaxies and that one of the lingering cosmological mysteries is why do galaxies formed clusters and superclusters? It is space itself that is expanding and the speed of the expansion is greater than the speed of light the farther away the galaxies are from each other (these superluminal speeds have been detected). This seems to imply that the size of the universe is larger than the size of its visible part.

Your two paragraphs above seem to contradict each other, AntonioLao.
If the space between galaxies is expanding greater than the speed of light, than surely the galaxies have to be moving away from each other at greater than the speed of light (at least in conventional physics terms).
I'll have a look at March's Scientific America and see if it's any more illuminating about these 'misconceptions'.

The idea that space itself is expanding is getting closer to Steadybang Theory (see the 'Your TOE Theory' forum and www.steadybang.com), where everything - matter and the space between it - is expanding. I think this makes more sense, but then, being it's author, I would.

Battybat.

[battybat]

I've looked at the Sci Am article now Antoniolao, and am amazed to see how far cosmologists will go to protect the 'Big Bang' idea, when it's threatened. It's taken on the mantle of a religion or creed and they'll dream up allsorts of fantasies to explain any anomalies that it throws up. We've heard of Dark Matter and Dark Energy (neither of which have been detected), now they're talking about 'cosmic red-shift' and the expansion of space (independantly of matter). Where will the list end?
Big Bang Theory was invented to explain the red-shift of light from distant stars and this, as far as I know, is the only evidence for its existence. Explain this a different way and Big Bang implodes! Surely a much simpler explanation for the red-shift is that it is just a symptom of optical jet-lag. After all, wouldn't it be even more amazing if light could travel through space for billions of years without changing its form in some way. Zwicky was on the right track with his Tired Light Theory but it was based on gravitational red-shift and that was deemed not enough to account for the shift. However in Steadybang Theory the flux-envelopes of all the celestial bodies extend till they meet each other, so the whole of space is filled with flux of various density - a sort of turbulent, expanding aether! It may be that this has an accumulating effect on the pulses of emr travelling through it and this causes the shift. Or it just might be that, in travelling so far, the timing of the pulses gets slightly out of synch and, as mentioned above, they succumb to a form of optical jet-lag.
Black Holes are another invention of modern cosmology with tenuous evidence to support them. They were invented to explain flaws in modern gravitational theory. Specifically, why some stars appear to be circling apparently empty space as if it were a heavy body, usually near the centres of galaxies and how the motion of stars in some galaxies can only be explained by the addition of some invisible mass. Of course in Steadybang the mechanism of gravity is a completely different concept. Matter is made up of spinning, expanding vortices (or vorticles) in an open spiral form (open spiral torus form at atomic level). These combine to form larger bodies, if the combination is stable, and this process continues ad infinitum. So spiral galaxies are mega super-vorticles made up of many stars spinning around an evolving centre.
I guess cosmologists have a lot of time and energy (and their livelihoods in some cases) tied up in Big Bang Theory and it's going to be difficult to change their minds. But if only a few did, there would be a snowball effect and within a few years most would realise that the universe makes more sense without BB.

Battybat.

[AntonioLao]

Originally Posted by battybat Big Bang Theory was invented to explain the red-shift of light from distant stars and this, as far as I know, is the only evidence for its existence.

the strongest evidence in support of the big bang theory is the detection of the cosmic background radiation, remnant of the big fireball at time zero. This radiation has a thermal energy of about 3 degrees kelvin (ancient old photons from the big bang itself but still travelling at lightspeed with much lesser energies). Thermal equilibrium between the energy from matter and energy from space expansion agrees perfectly with the recent findings of the COBE satellite to fit a blackbody radiation curve.

[StirkWagner]

One thing that always got me about the big bang is what caused the big bang and if there was nothing before that. Then how did that nothing become something?

[AntonioLao]

Originally Posted by StirkWagner One thing that always got me about the big bang is what caused the big bang and if there was nothing before that. Then how did that nothing become something?

at time zero, all physical laws are meaningless.
at time equals sec, Planck time, the universe came into existence at the Planck density of 1 Planck mass per unit volume of 1 Planck length diameter sphere, which is equivalent to grams per cubic centimeter.

[battybat]

Originally Posted by AntonioLao the strongest evidence in support of the big bang theory is the detection of the cosmic background radiation, remnant of the big fireball at time zero. This radiation has a thermal energy of about 3 degrees kelvin (ancient old photons from the big bang itself but still travelling at lightspeed with much lesser energies). Thermal equilibrium between the energy from matter and energy from space expansion agrees perfectly with the recent findings of the COBE satellite to fit a blackbody radiation curve.

Yes, detection of CMB radiation is given as confirmation of the BB. But according to the BB theorists, this was generated when the universe was only 300,000 years old and comparatively small. Surely, billions of years later, that radiation, travelling at the speed of light, must have scattered to the four corners of infinity and no longer exist, near Earth at any rate.

Battybat

[AntonioLao]

Originally Posted by Battybat Surely, billions of years later, that radiation, travelling at the speed of light, must have scattered to the four corners of infinity and no longer exist, near Earth at any rate.

another misconception is that BB has no detectable center. The CMB photons come from every possible directions and another mystery is the homogeneity and isotropy of the universe.

In order to surmount the flatness problem, cosmologists, like Alan Guth, came up with inflationary BB to replace the standard BB.

[StirkWagner]

Originally Posted by AntonioLao at time zero, all physical laws are meaningless. at time equals sec, Planck time, the universe came into existence at the Planck density of 1 Planck mass per unit volume of 1 Planck length diameter sphere, which is equivalent to grams per cubic centimeter.

That still doesn't explain it the way it should be explained. U can't use math or numbers to show what was there before the big bang. Everyone likes to think the universe is a complicated thing. I mean no disrespect but people like you who really think they understand it all really know pratically nothing just like the rest of us. If you are inteligent you should be inteligent enough to know that no matter how much you know, you know practically nothing at all.