Recent content by antd

The Universe is not spherical. Nobody knows what shape the universe is. Maybe you are talking about the observable universe, and that's spherical only because we cannot 'see' further (speed of light).

But this 'infinite', it seems it cannot really exist... Are you saying it is infinite because the expansion is faster than the speed of light? (in the flat universe) Surely it's a flaw in the current physical model, which is leading to this infinite

Then it seems that we don't know much about the Universe :P I don't know why anyone would say the universe is infinite though. Since it seems infinite cannot exist in reality. Shouldn't all scientists say 'our current theories are not compatible' or something to that extent... And yes, I think...

Yes, but this is a kind of concept which exists in the mind. It doesn't describe something that exists in reality.

But how can it be infinitely big? If the universe is infinite how can it make sense to say the universe is expanding? If something is infinite surely it doesn't need to expand, since it cannot get any bigger? And if it is infinite, surely we cannot know if it is expanding?! I read from NASA...

I have read in many places that the universe was once smaller than an atom. However, many people here have said this is a 'cartoon' version of the big bang theory. And that the media have popularized this invalid notion... I now have some questions, can I have the 'true' answer (what we know...

Thanks. Slowly learning not to trust wikipedia ;-)

I'm beginning to have a better understanding now! Although, Wikipedia says 'the speed of electricity' is often confused with 'the propagation speed of an electromagnetic wave'. So in that sense 'the speed of electricity' is the speed of the electrons, and not of the EM wave...

But how can it be explained in terms of speed? If the speed of electricity is slow (millimeters per second) how can the bulb light up instantly? Doesn't the 'electricity' have to travel the whole length of the wire? Or is it something like the single electrons pass it on to a neighboring...

I've read the thread but I still do not understand. Can someone help explain how the propagation of an electromagnetic wave is near the speed of light, but the speed of electricity is slow? (the water/traffic light analogies don't make sense to me) Does 'speed of electricity' mean the speed...

Thanks :)

S-FLEX = 1900RPM high CFM | 120mm fans CM Stock = 1000 RPM low CFM | 120mm fans Yellow = Intake Blue = Exhaust This is my PC Case and I'm buying 5 new fans. I overclock my computer, so I need as low temperatures as possible :) Speaking from a scientific stand-point. Does it make sense...

Hmm, but it seems as if the same photon is in two or more places at once... depending on how many observers there are?!

Wow, thanks, very interesting. So does the event horizon increase in size as the BH takes in more matter? It's bizarre how a point of zero space can have any gravitational attraction whatsoever, let alone the monstrous gravitation of a black hole... In your opinion do you think we will...

Hmm sorry, I don't understand the mathematics. I accept what you told me is true :) But it doesn't help me explaining how it is true... >.< For example, I don't know why the spaceship would see the photon far away from them But someone not moving and watching would see the photon close...