World, Writing, Wealth discussion
The Lounge: Chat. Relax. Unwind.
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Can sun be orbiting the Earth after all? -:)
I find physics and astronomy fascinating. The equivalent question today is does life exist on other works and do other universes exist out there, what is dark energy and dark matter, what is the mathematic inside a black hole or the Big Bang, is superstring theory real and can quantum mechanics and relativity be united. Lots of debate around these and some outsider egocentric doubters. Especially the life on other worlds debates.
Statistically, with the astronomical number of stars and of already discovered exoplanets, it is nearly absurd to still think that the Earth would be the only place in the Universe harboring life. We are not the center of the Universe and never were, despite all the religious fanatics who claim otherwise.
Michel I agree, I don't think the world will be surprised when we discover other life, but I'm sure we will be overcome with a sense of wonder, unless it is intelligent life far, far smarter than us. Then we might experience real trepidation
We have people today rejecting science and embracing a flat-Earth view. A belief that literally became obsolete thousands of years ago is now being accepted because there are those who think that "alternative facts" are somehow just as valid as real ones. Questioning scientific theories is all fine and good. But rejecting things that have been proven for centuries or longer out of a phony sense of skepticism is absurd. Oh, and the Moon rotates from west to east.
Two bodies actually rotate around the center of mass between them, so - in a sense - the sun orbits the Earth, just as the Earth orbits the sun.Matthew wrote: "We have people today rejecting science and embracing a flat-Earth view..."
I've heard about this being a thing. I find the flat-Earth view particularly troubling because you actually don't need science to refute it. Looking out over the ocean on a clear day will reveal an obviously convex horizon line.
Edit: I shouldn't say it's "obvious", but the curve is perceptible to anyone looking for it.
Matthew wrote: "We have people today rejecting science and embracing a flat-Earth view. A belief that literally became obsolete thousands of years ago is now being accepted because there are those who think that "..."As someone who works in mainstream health, I really worry about the rejection of science and the wander towards 'alternative facts.' The bizarre things being promoted and believed could lead to all kinds of disaster.
Leonie wrote: "Matthew wrote: "We have people today rejecting science and embracing a flat-Earth view. A belief that literally became obsolete thousands of years ago is now being accepted because there are those ..."Me too! It doesn't hurt me much, I just have to deal with stupid comments and tweets. But man, it brings us all down when people openly embrace ridiculous ideas based on conspiratorial beliefs!
To a certain extent, those who voted for Trump seemingly believe in a flat earth universe. Everything turns around whatever Trump says!!! I can't wait for him to spread apart the Atlantic to allow his WASP followers to cross over.
Bernard wrote: "To a certain extent, those who voted for Trump seemingly believe in a flat earth universe. Everything turns around whatever Trump says!!! I can't wait for him to spread apart the Atlantic to allow ..."
I love that picture XD
Aiden wrote: "I find physics and astronomy fascinating. ..."Me too. Watching Orion and Sirius almost nightly during winter months and thinking when they'll send emissaries.
Having no visas they might be denied entrance in certain places though -:)
Matthew wrote: "We have people today rejecting science and embracing a flat-Earth view. ..."Exactly, becomes the spirit of the epoch...
On the other hand, I can kinda imagine how religious dudes felt, when the notions of god and other divine beliefs ruling for millennia started to dim...
Matthew wrote: "We have people today rejecting science and embracing a flat-Earth view. A belief that literally became obsolete thousands of years ago is now being accepted because there are those who think that "..."Everyone is the center of the Universe. You are outside and away from my center. But of course, you too are the center and I'm outside your center. Can that be disproven?
There is also the hollow and the concave earth ideas that have been floating around for awhile.The problem with any of these beliefs is that they are, from a practical perspective, not refutable.
I've had lengthy and civil discussions on these topics with true believers, and any refuting evidence is simply deemed inadmissable (by multiple techniques, i.e. it's faked, mis-interpreted, or even just ignored, etc...)
So there is no practical way to change a believer's mind. I no longer engage in such conversations as it's a waste of my time.
I once ended up in a conversation with a Mormon who told me evolution didn't exist, there was no proof that was real. I said in response as far as I knew Mormons didn't exist and they were just made up, like the Loch Ness Monster. She said I was wrong because she was a Mormon. I said she was mistaken because they are not real.The conversation didn't get much further than that when we were both using the same approach of denial.
PS I do know that Mormons are a real religious organisation by the way. :)
The difference is in the words belief and fact. Believers have no need of facts they just believe.I believe they are wasting my time - they don't - my wife always sends me to the door whenever the religious groups turn up. This is the only time I think the UK should have more relaxed gun laws and an aggressive approach to trespass.
They believe in whatever they believe despite the facts - they think what they believe is fact.
I believe I'll win the lottery next week. The fact is I will not if I do not buy a ticket.
The real problem in society is not whether the earth goes around the sun but rather how can you tell? In other words, can you apply the scientific thinking to work out the answer? My guess has always been that most people simply can't be bothered. I tried to illustrate the method in my novel "Athene's Prophecy", in which Pallas Athene gave a young Roman the problem of proving the earth goes around the sun. No telescopes permitted, and he had to use knowledge as given then, including Aristotle's physics. You are, of course, allowed to use your eyes. Could you do it? As a hint, it was actually almost impossible for Aristotle to do it because there was a critical observation he could not make because of where he was. Your chances to guess. Game?
A good resource on the Ancient greeks & their approach to Astronomy is here; https://explorable.com/greek-astronomy
Ian wrote: "The real problem in society is not whether the earth goes around the sun but rather how can you tell? In other words, can you apply the scientific thinking to work out the answer? My guess has alwa..."I'm not sure, I'm not a scientist, nor a mathematician, but I think you can tell by the seasons, the pitch of the sun as we go around it.
GR, up to a point that is true, but it is very involved. You need to have developed a full mathematical model of each option, and when you do, there is something called an equant, which measures how far the projection of the sun goes. The Catholic church used this following Galileo to prove it, by having holes in cathedral roofs, carefully measuring the sun's projection, and doing the maths, which strictly speaking involves some calculus. But that wasn't the method I was thinking of. My method involves hardly any mathematics at all other than a bit of geometry, which is more suitable for the Roman period
Quite simply: it is mostly a matter of perspective. All motion is relative. If I am standing in the middle of a street watching a car speeding in my direction. I am also speeding toward a motionless car. The problem is that there are other objects that have to be accounted for. It is possible to say that the sun orbits the earth but the math is much less complicated if you say that earth is orbiting the sun.
Joe, motion is relative to a frame of reference, nevertheless suppose we want to employ the conservation laws? The kinetic energy of the sun orbiting the earth once a day is wildly different from the earth orbiting the sun once a year. However, it makes an awful lot more sense if we assume they each orbit a centre of mass (we get equipartition of energy and application of Newton's third law.) So while motion can be described in terms of relativity, in Galilean relativity it does matter which does what?
Ian wrote: "Joe, motion is relative to a frame of reference, nevertheless suppose we want to employ the conservation laws? The kinetic energy of the sun orbiting the earth once a day is wildly different from t..."I thought of that while I was trying to go to sleep last night. Sure, from a motion point of view, there is no difference between the car approaching me and me approaching the car. But the momentum and kinetic energy are dramatically different. Expand that to the solar system say and try to figure out how the planets could maintain stable orbits if everything is rotating around a stationary earth. Thanks for you reply - I love science.
In my "Legatus Legionis" in which my Roman puzzles this out, I used the logic as follows. Aristotle had worked out already that orbiting is falling towards the centre and moving away tangentially at the same time - the falling is important. He believes the earth rotates around the sun because the sun is bigger - Aristarchus proved that. Suppose the earth and the moon were exactly the same size, which would revolve around the other? He reasons with no reason to choose, they would both revolve around the middle, and from then it is straightforward to get to the concept that they each rotate around a centre of mass. As an aside, that reasoning is an important clue to my problem, how could a Roman prove the earth goes around the sun. Recall, he will believe the moon goes around the earth, and he knows the moon is much smaller, again from Aristarchus, who measured these things. Anyone prepared to give an answer? Or is too hard?
Ian wrote: "In my "Legatus Legionis" in which my Roman puzzles this out, I used the logic as follows. Aristotle had worked out already that orbiting is falling towards the centre and moving away tangentially a..."I am not sure. Things are not that well documented. Facts were not necessarily common knowledge just because someone had figured them out. I read that someone - I believe he was Roman - did a pretty good job of figuring out the distance to the sun. He found a hole in the ground that was only fully illuminated when the sun was directly over head. He knew what time of day that was going to happen (he had acquired an early Timex, I guess) so the measured the angle of a shadow cast in a town some distance away at the exact time the sun was directly over his hole in the ground. That allowed him to use trigonometry, which he no doubt thought of as geometry, to figure out the distance to the sun.
I bet that no one in Caesar's legions knew or even cared about the distance to the sun. The were probably pretty happy with the sun rising in the east and setting in the west - That's all a foot soldier really needs to know.
Joe, what you are describing is how the Greek Eratosthenes measured the size of the Earth. Aristarchus measured the distance of the Moon by geometry - two people at as far a distance as he could manage recorded the angle of when a lunar eclipse started. Two angles and a length defines a triangle. Knowing the distance and the angle the moon subtends gives its size. Naturally there were errors in the measurements. The distance to the sun was even more hairy. He waited until the Moon was half shaded and measured the angle to the sun. By definition, the angle on the Moon was a right angle, and he knew the distance. He therefore knew the distance to the sun. (There was a rather large error here because the angle between moon/earth/sun is very close to 90 degrees too - take a look at the tangent tables and see what an error of a degree makes! Clue - the tangent of 90 degrees is infinite, and it has to get there smoothly.)The novels have a good reason why the Roman was interested, but of course it is fiction. I did it because I felt that besides being interesting and exciting, I had to have a go at showing how science works, and I picked a topic that just about anyone could follow, once explained. However, I also feel very few people could work it out without help. So far, nobody has disappointed me. :-)
Ian wrote: "Joe, what you are describing is how the Greek Eratosthenes measured the size of the Earth. Aristarchus measured the distance of the Moon by geometry - two people at as far a distance as he could ma..."Ian, there was a good reason why ancient men were interested in such seemingly trivial questions and answers. They were brilliant and they had to think - it was in their DNA and we are better off because of it. I am sure your Roman had a good reason for what he did. There are probably more than a few real life Romans who did what your fictional character did. By the way, Hadrian's Wall was an engineering marvel built by illiterates using primitive tools. The pyramids are monuments to the engineering prowess of ancient peoples. I am intrigued. I am fascinated by the way those guys were able to figure things out without the history of math and science available to us today. I won't promise but I will try to read your book. But if you look at my "Want to read list" you will see that there is already a long waiting line of worthy tomes.
The ancients had considerable engineering prowess. If you look at the temple at Karnak, it is built on a hydraulic "earthquake protective system" that has stood for about 4,000 years, whereas my local cinema complex is being demolished after about 15 years life and one 7.8 earthquake. The sewage system of Rome still works after 2,000 yrs. If you read Robert Harris' account of Pompeii, he notes the aqueduct running around Vesuvius survived the pyroclastic flow and worked for a few hundred more years and then only failed because the routine maintenance required was not carried out. The geometry of Euclid was still taught in schools until recently, and the only changes are to make it more "user friendly". Their biggest problem was the horrible number system.
Nik wrote: "Aiden wrote: "I find physics and astronomy fascinating. ..."Me too. Watching Orion and Sirius almost nightly during winter months and thinking when they'll send emissaries.
Having no visas they ..."
First off, let me just say - FUNNY!
Second, you're getting into some Fermi Paradox stuff there. And that's a discussion that is definitely worth having! :)
Daniel J. wrote: "Two bodies actually rotate around the center of mass between them, so - in a sense - the sun orbits the Earth, just as the Earth orbits the sun...."Was seeing something a few years ago that the the Earth/Moon system is binary in that the center of the rotation is not exactly at the center of the Earth...it's close, but not exactly there meaning the Earth is revolving around the Moon as the Moon revolves around the Earth.
J.J. wrote: "Daniel J. wrote: "Two bodies actually rotate around the center of mass between them, so - in a sense - the sun orbits the Earth, just as the Earth orbits the sun...."Was seeing something a few ye..."
The moon is a fair percentage of the mass of the Earth. The Earth has the mass of a pimple compared to the sun and we're 93 million miles away from it.
J.J. wrote: "Daniel J. wrote: "Two bodies actually rotate around the center of mass between them, so - in a sense - the sun orbits the Earth, just as the Earth orbits the sun...."Was seeing something a few ye..."
Yep, much in the same way that the barycenter of our Solar System is not the Sun itself. It has a radial velocity caused by the gravitational influence of all the planet's orbiting it.
Well, launch a telescope to the solar system and find all about it. That's not so difficult to do these days. It will also show you images of whether nor not it is a flat world or a round. The earth and the Sun's orbit. But to the naked eye a full moon looks round and so does the sun when it sets. So rotundity is real not fiction.
Mehreen wrote: "Well, launch a telescope to the solar system and find all about it. That's not so difficult to do these days. It will also show you images of whether nor not it is a flat world or a round. The eart..."We already have space telescopes that do that. And in the coming years, we'll have more. There is no scientific basis for questioning heliocentrism or the fact that the planets are spherical. Not perfectly so, mind you. But as my pa would say "close enough for the girls I date!" ;)
Matthew wrote: "Mehreen wrote: "Well, launch a telescope to the solar system and find all about it. That's not so difficult to do these days. It will also show you images of whether nor not it is a flat world or a..."Ha, your pa sounds like a genius.
I'll be sure to tell him you said that. And you should hear some of the things HIS father said! But not here, they are not safe for work :)
Matthew wrote: "I'll be sure to tell him you said that. And you should hear some of the things HIS father said! But not here, they are not safe for work :)"HAHAHA. Tell them to add me to their facebook, if they have one.
One can posit any idea, but the question then becomes, which idea is the most elegant and employs the fewest variables, and also is more consistent with other observations. Even when people believed that the sun went around the Earth, the mathematics to support such a model had grown impractically complex.
Complexity of mathematics is not recognized flaw in physics, in fact some seem to like it. Try your hand at general relativity - in comparison, Claudius Ptolemy's maths were trivial
But GR has an elegance that epicycles never did
I am glad your mathematical ability is good enough to see the elegance. Me, I just find it so damn difficult . . .
In cartography, there is a noticeable acceptance of different models for practical reasons. For example, we use flat maps for small local areas of the Earth's surface, then we switch to distorted projections and globes as altitude increases. Similarly, we can use Newtonian physics instead of GR to compute orbits where precision is overkill. There's no "wrong" model per se. If a farmer needs to know where the sun will be and when, an Earth-centric model might very well be easier for him, and pushing "the truth" of heliocentrism upon him could be an unnecessary effort.
Because your eyes define their own frame of reference. Relativity 101 :-)
Many years ago I was on a Survival, Escape and Evasion exercise. My group got broken up and I was on my own. I was following a path but I had to deviate to help a fellow GI. That left us both lost. I was able to guide us back to the finish line by locating the Big Dipper and the North Star. Well actually another guy joined us and we became completely lost so we slept until dawn. Then I was able to use the sun to figure out how to finish the course.If we had had to use Relativity theory to solve that problem we would have been up shit's creek. So I tend to trust my eyes first and only use theory as a last resort.
By the way, Relativity 101 starts with Galilean relativity, which permits you to define your own frame of reference, and that is what your brain sees. For example, you are in a boat. Your boat speed is in the frame of reference of the water, but in the ocean you have no idea how fast that is going in the frame of reverence of the planet.
Ian wrote: "By the way, Relativity 101 starts with Galilean relativity, which permits you to define your own frame of reference, and that is what your brain sees. For example, you are in a boat. Your boat spee..."I am pretty sure that is not going to help much when you are dropped off on unfamiliar territory and told to find your way home without using your iPad
ipad? Who relies on that? Sun and trusty watch does me. Yeah, I know, with my luck it will be cloudy, in which case you have to guess the time zone you are in.Going back a bit in this discussion, the whole point of Galilean relativity is that if you are on Earth, everything looks like it is going around you because at first sight, there is no need to think your frame of reference (the ground) is moving. One of my novels had the premise that a Roman had to prove the heliocentric model. The idea was to show how science actually works, but needless to say it was more in the running for worst seller than best seller.
However, it's popular to question scientific theories and discover their limits, so can the sun like the moon still rotate somewhere from East to West? Not an entirely serious question, but egocentric individuals, who believe everything rotates around them anyway might be a little skeptical about heliocentric theories -:)