Robittybob1

That makes you sound as being obstinate. Just because your quote comes from scripture doesn't make it a fact.

Has history verified that? Have you got proof?

They are allowed to have an opinion.

That would require each family to produce 4 viable offspring per generation. China's one child policy definitely was set too low and now they have brought that up to 2, AFAIK. You need 2 or more per family just to break even (in an ideal situation). In historic times even if every family had 4 kids, when you take disease, accidents, wars etc into account the population would be barely climbing (my guess again sorry). I've heard this said before. So that would depend on where he lived, for if he came down to Southland NZ (where I used to live) on a clear night with good eyesight you would see a whole lot more stars (I'd guess probably 100x more) than in Iraq or wherever Abraham supposedly was at the time. Was that prophecy dependent on Abraham's eyesight, or was it the actual number of stars there was in the Universe"?

Could that number only be achieved if the descendents of Abraham inhabit new worlds? It is hard to imagine the Earth supporting more than 10 billion humans for the next 5 billion years. Even that might not be enough time to get to 10^29.

I find the maths of the situation a lot more interesting. Can a man ever have 10^29 descendents?

As I said "when I read Genesis", I read this and considered the implications. It challenges believers and unbelievers. Half the active threads (that are favorites of mine) on the forum seem to have some religious philosophical aspect to them. It seems a very topical myth.

When I first read Genesis I was amazed by this particular sentence So with Hubble we have began to count the number of stars. Without going into full details I have just Googled "the number of stars in the Universe" and got the result: Would it ever be possible to have that many descendents? My first thought was that the Earth would have to be around for a hell of long time for that to happen. I have not attempted to time that, i.e to do the calculation. Even if we humans could keep the population at 10 billion how many generations would that be? Is the Solar system going to last that long? Even in this rough calculation there are so many errors, but it might just give us an idea how long Abraham's descendents will need to be around.

Is there any truth to his existence? What did he really do to get all this respect?

I had sort of understood this as well, with the time dilation on the geoid being the same no matter where it was measured. Elevation then is like bumps on the surface (land height above sea level, mountains etc) is that what you meant?

Just seeing if I misunderstand you on this one point only. (The rest of it, I think I got it.) Breaking down the quoted portion: "He" refers to far off observer looking at both the orbiting clock and one resting on the surface (of the rotating Earth). Can that part "(of the rotating Earth)" be added or not? "both clocks" refers to the one on the surface and the one in orbit 9558 km from the center of the Earth. "he is at rest with respect to the surface clock" So does this just occur only for an instant, for if he was to maintain that he would need to be orbiting at a height where the orbital speed is the same as the rate of the surface of the Earth (I don't know at what height (x) that occurs). Is that possible and would that equation hold if the distant observer was orbiting at that height (x)? If two clocks are ticking at the same rate e.g the one on the surface and the one in orbit 9558 km from the center of the Earth, will they always appear to be ticking at the same rate to everyone else? (Not to their own clock's tick rate but the tick rate signal received from the other two, or is this always dependent on the relative velocity being zero to the "surface clock".)

So do you disagree with Swansont's post http://www.scienceforums.net/topic/95329-time-dilation-in-special-vs-general-relativity/page-2#entry922497? I am having trouble and I must admit I haven't got the problem licked yet. I found a chart in Wikipedia that might help. https://commons.wikimedia.org/wiki/File:Orbit_times.svg This graph shows what I have been trying to calculate. The "net orbital time gain line" meets zero line at just below 10,000 km from the Earth's center. This is the r value in the equations. Considering the Earth's radius is 6371 km and I estimated the satellite height of 3185 km that adds to 9558 km from the Earth's center. These figures match the chart. Have I misunderstood what the chart is showing? Associated with the article https://en.wikipedia.org/wiki/Error_analysis_for_the_Global_Positioning_System

It has and you remember how much bother these Biblical verses caused me. I'll pass thanks.

Note I am seriously wrong here. I will correct it later. If I wanted GTD and VTD to be equal but opposite this next equation needs to be equal to 1 not zero [latex]T = 1 \sqrt{1-\frac{2GM}{rc^2}- \frac{v^2}{c^2}}=0 [/latex] [latex]T = 1 \sqrt{1-\frac{2GM}{rc^2}- \frac{v^2}{c^2}}= 1 [/latex] I may need to rethink the algebra on this one sorry.

What was also amazing was the thought that the dolphins understood the two hand gestures to "create a trick done together". Then shortly after they got that right.

Is this the same as saying it orbits at a height (from the mean Earth's radius) that is half the Earth's mean radius? (A whole and a half gives the 3/2 fraction. This is value I had proposed on another site but I was told I was wrong. I trust your result totally. As above ""The effects cancel at [latex]\approx 9545 kilometers[/latex]" My spreadsheet result was 9556814 m (9557 km) so there is a small difference only. Thank you very much. PS: I was using Earth radius = 6371000 m, that times 3/2 = 9556500 m. The result above was the first value that was after the change in sign so that would explain the small difference of the additional 314 meters for I was changing the velocity by 1 km/h increments.

I struggled to find that reference. I click the link and a page comes up but no figures are on it. Do I have to scroll through the document? I've downloaded the document http://relativity.livingreviews.org/Articles/lrr-2003-1/download/lrr-2003-1Color.pdf and the figures are showing up OK. thanks.

I wasn't trying to correct Janus, I was just trying to work out which bit was the time dilation factor (so it is the bit under the square root sign. You say both t' and T start at 0 i.e. that is when t'=T=0, I presume. So to see how much time dilation there was I subtracted t'-T = TD (time dilation) [is t'-T = TD (time dilation) a valid way of looking at it?]. I then tried to look for the region around the Earth in which an orbiting satellite experiences gravitational time dilation (GTD) equal but opposite to the velocity dependent TD (VTD). Since in #7 it is agreed that: I was looking for the situation where instead of T(International Space Station)<T(GPS satellite) both would have combined time dilation of zero, where T(New satelite)=T(on Earth surface).

Could you check my edit of the post prior to yours please? It is not quite along your line but similar. I might be wrong, but tomorrow I'll recheck it.

I'll repeat: if you want to teach scientists you have to first learn a lot more science.

If the second formula is the combined effect, what is the first one measuring? Since it hasn't got a velocity term in it I was suspecting it is the gravitational time dilation at that radius value. Was that correct? I made [math] t' = 1 [/math] and compared the result to the orbital speeds, and there was point where the results became extremely small and then changed signs. I think this must be the point where "the combined effect of gravitational and relative velocity time dilation effects" = zero. In other words [math]T = 1 \sqrt{1-\frac{2GM}{rc^2}- \frac{v^2}{c^2}}=0[/math] Which must mean [math]{1-\frac{2GM}{rc^2}- \frac{v^2}{c^2}}=0[/math] The sqrt of zero is zero (that makes sense, and confirmed). So why would that expression become zero? That can only happen when both fractions are equal and equal to -1/2. ie 1 - 1/2 - 1/2 = 0 Do you agree? PS: No that is wrong. Both fractions just have to add to -1 they don't both need to be equal to -1/2. What is the value of the fractions when ""the combined effect of gravitational and relative velocity time dilation effects" = zero""? I'll look at this again tomorrow.

What is the source of your quote? .

Think about it. If they require air for propulsion and flight they are of earth origin. So who and where are they being made? So that question seems difficult unless it was somewhere deep under the ocean. Then if that was the case they would need to be able to go through water to incredible depths as well. How do you get around to these objections to air based propulsion?

Thanks Janus Just one clarifying comment regarding [math]T = t' \sqrt{1-\frac{3GM}{rc^2}}[/math] the [math]T [/math] is the "time dilation factor" so what units will this have? [math] t' [/math] What and where is that measured? I take it as a reading from a clock beside the distant observer, but if it is a clock do we put a period of time into the equation e.g. 1 second or 60 seconds? How does one put a number to this [math] t' [/math] when making a calculation? Sorry for being a bit thick about this, but I'll get it soon. Can I just say [math] t' = 1 [/math] second so [latex]T = t' \sqrt{1-\frac{3GM}{rc^2}}[/latex] becomes [latex]T = \sqrt{1-\frac{3GM}{rc^2}}[/latex]?

I'd say if you want to teach scientists you have to learn science.