13 Apr 06
Originally posted by AlcraAnd what topology of the universe at a whole did you use? Just plain flat as an approximation? What is the current value of Hubble constant? Is it really constant?
OK, we have come pretty close to each other, using two different techniques.
Any other ideas?
Do we know about the ration between number of protons and number of neutrons to calculate the mass of the universe in form of ordinary matter? What about other heavy exotic particles? Do we really know? And how much does our answer differ from the true value? Do we make any error estimations? Any thoughts about that?
Does the number of protons = 3.5 x 10^78 any real value at all? Or it is only a brainteaser that any answer will do?
Do any one care, anyway? Am I a fun killer... 🙄
13 Apr 06
Originally posted by FabianFnasYou are making the problem unnecessarily complex. The original questions was in terms of the "known universe".
And what topology of the universe at a whole did you use? Just plain flat as an approximation? What is the current value of Hubble constant? Is it really constant?
Do we know about the ration between number of protons and number of neutrons to calculate the mass of the universe in form of ordinary matter? What about other heavy exotic particles? Do we ...[text shortened]... only a brainteaser that any answer will do?
Do any one care, anyway? Am I a fun killer... 🙄
Take any definition you want of that, explain your thought processes, and provide an answer.
16 Apr 06
1 edit
Originally posted by AlcraIf we just want to have an answer, any answer, right one or false, than we are fully satisfied.
You are making the problem unnecessarily complex. The original questions was in terms of the "known universe".
Take any definition you want of that, explain your thought processes, and provide an answer.
But if we really want a discussion about the proposed answer then I am on the right way.
Noone has taken the topology of the universe into consideration. If we do, then the answer could be much less or much more as the proposed number of protons. The topology is imprortant even if we take the size of the known universe.
Perhaps the known universe is the whole universe considering you can observe the background radiation in every direction. And the source of background radiation is known...
Do you have any thought of the kind?
23 Apr 06
2 edits
My calculation was using a flat universe (which is pretty well accepted to be true), Hubble constant = 71 km/s/Mpc, to within a few (although that doesn't figure into how many protons there are today in the visible universe), and of course, the Hubble parameter is not constant over time, it changes because the universe is expanding due to the dominance of dark energy over other forms of energy in the universe.
The background radiation is always visible throughout time. It is just the light that is finally reaching us from the distance equivalent to the age of the universe times the speed of light. (Actually, it would be the age of the universe minus about 300,000 years, which is roughly the time those photons had their last scattering.)
24 Apr 06
Originally posted by sven1000No, not considered beeing the truth, more considered beeing a fair approximation until you know more about topology of the universe.
My calculation was using a flat universe (which is pretty well accepted to be true)
We don't know anything about the topology yet. We're just guessing.
24 Apr 06
Originally posted by FabianFnasI don't mean 'you', the sentence would better read: "until *one knows* more about topology of the universe"
No, not considered beeing the truth, more considered beeing a fair approximation until you know more about topology of the universe.
(English is not my mother tongue.)
27 Apr 06
1 edit
Originally posted by ark13You're perfectly right. The number of protons are not constant, regardless of expansion or not.
No one has brought up the fact that the answer to this question would constantly change, even if the known universe didn't expand. In beta decay, a form of radioactive decay, a nuetron is converted into a proton and an electron.
So - has the actual answer ("What is the number of protons in the Universe?"😉 any meaning at all? If we discussed the mass of universe, expressed by proton mass equivalence, that's one thing, but now we try to count the numbers of protons. Not the neutrons, not other heavy particles, just protons.
The collected mass of the universe, not only the region which is known, but the entire universe, is crucial for understanding the topology of universe. Flat, parabolic, hyperbolic topology. And before we know that, we can only guess the number of protons (and neutrons).
And so far I haven't mention the so called dark matter, and dark energy, that make the universe behave in a totally new fashion compared with our view ten years ago. Do we know more - or less now?
02 May 06
Originally posted by FabianFnasThis is actually the field I work in, and we know pretty well that it is a flat universe.
No, not considered beeing the truth, more considered beeing a fair approximation until you know more about topology of the universe.
We don't know anything about the topology yet. We're just guessing.