withdrawl clinic Posted November 22, 2021 Share Posted November 22, 2021 hi! i have educated myselfe a lot regarding, big bang, particle physics, dark matter and dark energy, and black holes. now my mild dyslexia makes some of thos aspects of particle sience quite difficult, as for example my brain struggles to seperate neutrons from neutrinos. i saked my selfe a lot of questions and only some of them got answered over the years by sheare chance, by some lectures. i start this thread with the hope that some members here love this topic as well, and we could get a platform of ideas going... one thing i struggled for a long time, was, if light is made out of photons, wich have no gravity, why do there beams get bent by heavy objects (gravitational lensing). now i know that the light gets only seemingly bent because of space time!! the james webb space telescope will be lauched soon, and i am very excited as it will make us look further back in time than ever befor. but some people say it should get a name change, as james webb was not nice to some people... when i was a boy and started out with astronomy, people said, one cannot build bigger telescopes than mount palomar. but with computers help we can now. computers helped us to discover many new objects, trans neptune objects, and even an earth trojan!! which is a space object sharing the same path as earth, but sits at a lagrange point. james webb will be placed at a lagrange point as well. what excites you, regarding the universe? we are all made out of "star stuff", held together by "forces"!! maybe somebody can answer me two questions: a massive sun displays more gravitational force than say our little earth. a black hole even more so, but by this newtonian law, heavier objects should fall faster than light ones but they don't. i support modified newtonian gravity laws, and superfluids instead of dark mater and dark force. this new theory first suggested by khoury (my hero) says maybe gravitational laws don't scale the way we think they do. and is the infinite small nucleus of a black hole, particles just squeezed together, without any space in between? black holes in my intuition get squeezed to infinitly small, by the higgs bosson. 2 Quote Link to comment Share on other sites More sharing options...
Micromegas Posted November 23, 2021 Share Posted November 23, 2021 Hi withdrawal clinic good questions. Things in the universe don't excite me in the sense you mean, I like science for the insight into human epistemology and hubris it provides. Re: light bending. Light does not bend because gravity is pushing and pulling it as per Newton's gravitational theory, light bends going around massive objects because those objects are bending space time as per the Theory of General Relativity. The proof of Einstein's theory was the deviation in the light from Mercury as it was passing the sun in a total eclipse in 1919. The sun bends spacetime therefore if light goes close to it, it follows the bent curvature of spacetime. One of the places those observations were made was in the northwest of Australia between Port Hedland and Broome, teams of aboriginal people lugged camel-trains of observational equipment to a remote beach to see the light from Mercury bend! The other question, things falling at the same rate has to due with the constant rate of gravitational acceleration 9.8m/s "g" for objects close to the surface of the earth. The rate is determined by the mass of the earth. If a 1000kg and a 1kg object are dropped at the same time, gravity has a stronger force on the larger object, which should make it move more quickly, but this greater force is cancelled by greater mass (i.e. it's harder to "push"); the same in reverse, a 1kg object has less force, so less speed, but less mass also, so easier to '"move". The cancelling of force and mass leaves a constant acceleration common to them both, determined by the mass of the earth. This law is the same everywhere only "g" is different depending on the massive body (e.g. Jupiter has different "g" than earth). Regarding the new theories, in science, at massive scales and minute scales, deterministic laws break down. I suspect this has to do with limitation in human cognitive capacity which will not ever be overcome, although the quantitative understanding of phenomena (and technical use of that knowledge) will nevertheless continue to increase indefinitely. 2 Quote Link to comment Share on other sites More sharing options...
Halcyon Daze Posted November 23, 2021 Share Posted November 23, 2021 (edited) On 22/11/2021 at 11:28 AM, withdrawl clinic said: when i was a boy and started out with astronomy, people said, one cannot build bigger telescopes than mount palomar. but with computers help we can now. Sorry if this doesn't answer any of your questions. I think that the reason they say Mt Palomar is like the maximum size for a telescope (on earth) is that interference from earth's atmosphere makes the images blurry when zooming in on the most distant objects. So the Hubble and James Webb can overcome this problem by being outside the earth's atmosphere. They could hypothetically make a telescope as big as they want out in space and the image quality would improve the bigger they make the lens/mirror, but then warping from gravity would also degrade the quality of the image, and be very hard and expensive to overcome. That's where computers come in. If the image is digital they can process the information to artificially remove the blurryness, and give a better idea of what it really looks like. It's certainly an improvement on those distant blurry objects. And maybe the James Webb will help them calibrate their computer processes to become even more acurate. Also objects in space fall differently to objects on earth due to resistance from the air, so that's why a feather and a hammer fall at the same speed on the moon, because there is very little wind resistance form the negligable atmosphere. As for light, I always thought it had a very tiny amount of mass, and that's why it can't escape black holes, but that theory might have been updated, not sure. Edited November 23, 2021 by Halcyon Daze 1 Quote Link to comment Share on other sites More sharing options...
withdrawl clinic Posted November 24, 2021 Author Share Posted November 24, 2021 (edited) mm, thx for reminding me of the mercury transveres, the sun story. yep that was how einstein was proofen right. now a telescope is in the planing stage to use our sun as a gravitational lens, with the aim to get pictures from planets (exo planets) from distant suns. it will have two parts a shield to cover the sun, and the camera, both very far away. hd, the mount palomar mirror is solid glass. the very large telescope, has segmented mirrors, and not out of glass, to overcome the blurring effects, all big telescopes, shoot out a laser beam, which tells the computer instantly how to correct the image. https://en.wikipedia.org/wiki/Very_Large_Telescope Edited November 24, 2021 by withdrawl clinic 1 Quote Link to comment Share on other sites More sharing options...
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