How many protons, neutrons and electrons are there?

[ZenBeam]

@Exapno_Mapcase

10[sup]45[/sup] is half of 2 x 10[sup]45[/sup]. If you double that you get 4 x 10[sup]45[/sup]. Double it again at you’re at 8 x 10[sup]45[/sup]. You haven’t even gone up one order of magnitude despite three doublings.

You’re missing their point.

[Exapno_Mapcase]

I think that the way these posts were made reinforces the OP’s mistaken idea that a 45 in a power of ten is somehow halfway to a 100 in a power of ten. Powers of ten do not work that way at all. Moreover, the lack of understanding that this is the case is a common problem. Trying to excuse away that misunderstanding by throwing in logarithms doesn’t make it right or lead to the OP - and anybody else reading this thread - understanding where he went wrong.

[RadicalPi]

@Polycarp

Very nice job. I’d add that with cosmic abundances of nuclides being what they are, well over 90% of all known (non-dark matter) atoms are protium (H-1), with proton and electron but no neutron, and over 98% of the remainder is helium-4, with two protons, two neutrons, and two electrons So estimating that “no more than half the particles counted thus far are neutrons” is a gross understatement. In any controlled sample of nucleons, very much less than ten percent will be neutrons, and in a smilar sample of necleons+electrons, the neutron count will be well below 5%. Therefore I’d scale down your 1.4910[sup]82[/sup] to the close order of 1.010[sup]82[/sup].

Thanks. That last part was the biggest guess, since I have no idea whatsoever how many neutrons there are. Hence my hedging.

[septimus]

I think OP is not wrong to conclude that an ocean is (logarithmically) “about midway in mass” between an atom and the universe. He just draws the wrong conclusion: the universe is hugely larger than an ocean, but so is an ocean hugely larger than an atom.

Here is a wonderful webpage (Scale of the Universe) which everyone will want to bookmark. Use the slider at bottom to see different scales.

[Half_Man_Half_Wit]

As an interesting historical nugget, John Wheeler and Richard Feynman toyed around with the idea that the total number of electrons in the universe is – one. The reason for why this ‘works’ at all is essentially that one can view a positron as an electron going ‘backwards in time’, so all the electrons (and positrons) we see are really just the one zipping forward and backward; every annihilation of a positron and an electron, or conversely the photoproduction of an electron-positron pair, would then be just the ‘one electron’ ‘turning around’ in its propagation through time. The obvious problem, of course, is that there don’t seem to be nearly as many positrons as there are electrons.

[Chronos]

The other problem is that one can produce an electron-positron pair, interact with and measure one of the pair, and then re-annihilate them. That gives you an electron that definitely isn’t just a slice of “the one electron”.