Recent content by Brook

Thanks for your response Simon. I guess you mean the wikipedia article on vacuum. Ok well let's get comfortable with the classical concept. So if the materials of the universe are inside a huge nothingness, then does it mean that this nothingness is infinite? This seems strange, because the...

Hi what constitutes a vacuum? I mean it has to be made of something, since it it part of the space time continuum. In school you learn that a vacuum is empty space or area without matter, but it occurs to me that a vacuum must be made of something and there must be something there. What is it...

ok let me read some of this stuff and get back...thanks thus far...

hmmm... so where does the energy go when the photon wavelength expands? and is this red shift the only evidence that we have of an expanding universe?

right, so the velocities needed to explain the red shifts would be too great...were these assumed velocities approaching light speed?

So let me see if I get this... If the doppler effect was used to interpret the red shifts then it wouldn't make sense because the red shifts calculated would be too large to be explained by the velocity of the galaxies? So instead of the red shift being due to the velocity of the galaxy it...

can you explain this further. I know that the doppler effect can show which direction things are orbiting when viewed from earth. Why can't the doppler effect explain the red shift seen for distant galaxies? why would this mean that the universe is not expanding?

so how does expansion create a red shift? what is the mechanism...

And the red shift seen in the distant galaxies...is this due to the expansion or to the doppler effect?

If space is expanding then how did the planets and stars come together to form galaxies? Why are the galaxies themselves not expanding and the solar system not expanding?

thanks everyone for your ideas...

So according to wiki Thorium has a half life that is large and Bismuth's haf life is fantastically huge... thanks... Are there any elements with a short half life that is less the the age of the earth. If so how are they preserved from disappearing all together?

hmmm... So I checked out uranium and saw that for U238 the half life is 4.4 billion years while for U235 it's 700 million. I believe lead is the highest stable atom. Which element above lead is naturally occurring and is never created by the decay of any higher atom?

Very insightful responses thanks... Any ideas on this?

please elaborate on this question you are posing...I thought the math was derived from the physics, so it has to follow it...