Recent content by iced199

I'm mainly talking about the general trend of half lives shortening in elements heavier than lead. They all decrease in a curve, with the exception of uranium and thorium. They're outliers. Why?

Why is it that those atoms, with atomic numbers of 90 and 92 have much, much longer half lives than atoms like Radon, Radium, and Polonium? I do realize that atoms with even atomic numbers are more stable than ones with odd numbers, so it makes sense why atoms like astatine, actinium, and...

This probably seems naiive, but why? My main question being that why isn't hydrogen the most stable. It is the simplest and should be, right? If everything wants to arrive at the lowest possible energy state, why do nuclei want to arrive at iron? I can understand splitting atoms (fission)...

I just find it interesting that this was found on independence day. Go figure. :D

So is the extra mass from the energy of the newly created proton opposing the nucleus or am i completely missing this?

If the free neutron decays in only 15 minutes, why are neutrons in the nucleus attached to protons stable? This has always bewildered me. Just a side question, are 'tetraneutrons' stable or even possible?

Even if you could somehow blow apart a black hole, which seems impossible because trying to do so would just make the black hole larger, it would break into smaller black holes, which could merge back into the original. Nothing changed.

I am pretty sure they don't, but Wikipedia says that their lifetime is about 10^26 years. Then it says they are stable because they are the lightest particle to have an electric charge. I am confused now. It can't decay because if it did, it would violate charge conservation, since two lighter...

Actually, neutron stars have a thin layer of a superhard crust of normal nuclei. This crust keeps the main neutron star material underneath stable. But it does experience proton decay. So slowly the crust will decay and the layer below of neutrons then decays into more protons that then decay...

Thank you! That solves it! :D

Oh. So does the fact that Lambda is 0.3 is approximately the amount of normal matter plus dark matter percentage and that dark energy is approximately 0.7 and 70% mean anything? I think that was a contributing factor to the advocation of dark energy, right? Just an observation.

The WMAP satellite found that the universe consists of 74% dark energy, 22% dark matter, and 4% normal matter. I can understand how they found the dark matter and normal matter, but how do find something that doesn't interact with anything and is a property of space itself? And how did it...

This is just something I heard in a book by Michio Kaku: matter and energy both have positive mass and energy. Gravity is a negative energy. So in effect, they both cancel out. If you added up all the mass and energy in the universe and subtracted the amount of gravitational energy, you would...

As already stated, the expansion is from dark energy, not the weakening of gravity. If that were true, galaxies, solar systems, stars, and planets would all start slowly falling apart, since the other three forces do not play a role in keeping the together.

With our stars consuming hydrogen to make helium, how much has been consumed since the Big Bang? I know 73 or so percent of the total mass of the visible universe is hydrogen, so how much has been consumed? IE, what was the original proportion of hydrogen to helium to other elements? I know we...