beecee

The answer is yes to both. Maxwell’s equations can very easily be generalised to curved spacetimes; in fact all you need to do here is write them in terms of the differential forms formalism, which is fully covariant. Likewise, EM fields function as sources of gravity - all you need to do here is insert the stress-energy tensor for the electromagnetic field into the Einstein equations. Ideally one of these (either a metric, or an EM field) will be given, and you can then calculate the other. If you know only a distribution of sources, but neither metric nor EM field, then you will need to solve a system of equations that comprises both the Maxwell and the Einstein equations. This is potentially very challenging, mathematically speaking. But yes, EM fields influence the geometry of spacetime, and the geometry of spacetime influences EM fields. It’s a pretty complex and non-linear “feedback system”. While I understand that charge, mass and angular momentum are the only three properties a BH can have, charge would be quickly negated, would it not? and over far longer periods of time, so to would angular momentum. In other words the Schwarzchild metric while obviously being the simplest, is also the end state of all BH's.

Overall I believe popular science articles in the mainstream press, do far more good then any potential misunderstandings due to sensationalism. And while recognising that, any potential misunderstanding/s can be alleviated by further checking out news outlets and asking questions if one is interested in any particular item that is revealed. In fact I will go as far as to say mainstream press popular science outlets are totally necessary if scientific discoveries etc, are to spark any interest in science at the public level..eg: The recent discoveries of GW's sparked tremendous interest in my country, and were publicised as "ripples in spacetime". With that example, in my opinion at least, not enough information was released at least with regards to what a GW would actually do if it were large enough and should pass our way. Finally I believe any thinking person should know, that journalistic sensationalism is par for the course and exists in near all forms of news item releases. And obviously if any form of personal involvement was to be anticipated [say buying a new car after seeing an advert] then further research into said car is a must. Good idea!

OK, thanks. got it.

https://phys.org/news/2018-08-quest-source-black-hole-dark.html Quest for source of black hole dark matter August 14, 2018 by Anne M Stark, Lawrence Livermore National Laboratory Like a game of "hide and seek," Lawrence Livermore astrophysicists know that there are black holes hiding in the Milky Way, just not where. "If they find them toward the galactic bulge (a tightly packed group of stars) and the Magellanic Clouds, then black holes as massive as 10,000 times the mass of the sun might make up dark matter. If they are only toward the galactic bulge then they are probably just from a few dead stars." Read more at: https://phys.org/news/2018-08-quest-source-black-hole-dark.html#jCp extract: "We are developing a novel means of microlensing detection that will enable us to detect the parallactic microlensing signature associated with black holes in this mass range," Dawson said. "We will detect and constrain the fraction of dark matter composed of intermediate mass black holes and measure their mass spectrum in the Milky Way." Read more at: https://phys.org/news/2018-08-quest-source-black-hole-dark.html#jCp """""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""""" https://academic.oup.com/mnras/article-abstract/476/1/2/4797182?redirectedFrom=fulltext# Primordial black holes as dark matter: constraints from compact ultra-faint dwarfs: Abstract The ground-breaking detections of gravitational waves from black hole mergers by LIGO have rekindled interest in primordial black holes (PBHs) and the possibility of dark matter being composed of PBHs. It has been suggested that PBHs of tens of solar masses could serve as dark matter candidates. Recent analytical studies demonstrated that compact ultra-faint dwarf galaxies can serve as a sensitive test for the PBH dark matter hypothesis, since stars in such a halo-dominated system would be heated by the more massive PBHs, their present-day distribution can provide strong constraints on PBH mass. In this study, we further explore this scenario with more detailed calculations, using a combination of dynamical simulations and Bayesian inference methods. The joint evolution of stars and PBH dark matter is followed with a Fokker–Planck code PHASEFLOW. We run a large suite of such simulations for different dark matter parameters, then use a Markov chain Monte Carlo approach to constrain the PBH properties with observations of ultra-faint galaxies. We find that two-body relaxation between the stars and PBH drives up the stellar core size, and increases the central stellar velocity dispersion. Using the observed half-light radius and velocity dispersion of stars in the compact ultra-faint dwarf galaxies as joint constraints, we infer that these dwarfs may have a cored dark matter halo with the central density in the range of 1–2 M⊙pc − 3, and that the PBHs may have a mass range of 2–14 M⊙ if they constitute all or a substantial fraction of the dark matter. :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: I see this as interesting research which may lead to the probable answer to one of cosmology's most asked question. But my first thought/s, would be does it or can it, explain the "Bullet Cluster" observation?

So pray tell, what is the electron in an atom of hydrogen pushing against? Leaving that pseudo claim........ Great detailed answer Marcus! This is obviously Pauli's exclusion principle in operation, correct?

Most scientists do accept that we are probably not alone in this universe. Many reasons for that starting with the fact that Earth does not hold any privileged position. Along with the facts that the "near infinite" extent and content of the universe, and the stuff of life being everywhere we look, leads reasonable opinion to conclude that we are not alone. Still the fact remains that so far we do not have any convincing evidence of any life off this Earth, let alone any Alien visitations and anal probing on Earth. Those are the facts at this time, not withstanding the sensational claims of impressionable gullible folk who are so fascinated and in awe of mystique in the world around them, that it clouds any logical judgement on their part.

Doesn't the BB only apply to the observable universe? What we do know with reasonable confidence is that there was a time at t+10-43 seconds when our visible universe was incredibly small, much hotter and unimaginably dense. The BB wasn't a "point", it was just an event at which we actually have no knowledge, when the whole universe/space/time apparently started expanding and which we are able to reasonably make sense of at the aforementioned t+10-43 seconds. Perhaps the term singularity is misleading as many take it to mean a point of infinite density, when in actual fact, speaking physically , it need not actually be infinite but may lead to infinite qualities. Speaking mathematically of course, it is simply where our models, equations and laws simply don't compute.

I believe one of my favourite link may give some idea,,,,,,,https://www.astrosociety.org/publication/a-universe-from-nothing/

And who created this god? https://www.youtube.com/watch?v=G4a7F6dOdlc And I noticed you posted the above in a positive manner only 9 hours ago, after joining this forum only 11 hours ago [welcome] .....Why with an obvious religious and god fearing persona, did you chose to join a science forum where you would obviously be aware that other explanations of how the stars, planets and us came to be? Do you see science as a threat to your ancient long held beliefs?

That's a sample of what we have to deal with when asked the simple question of when are you going to present this evidence or proof of your claim. Do you really expect to be taken seriously? Again if we go back a few pages it is seen that you were even ignorant of what a scientific theory was....So again, you need to [1] Learn the scientific method, [2] Learn what a scientific theory entails, [3] Study up on SR/GR, [4] Be aware why both are validated, verified and have practical applications, [5] Be aware before you make any outrageous claims against incumbent models/theories, evidence is necessary to support your hypothetical, [6] Or an experiment invalidating the incumbent model/theory and aligned with your own hypothetical, [7] Answer all relevant questions about your hypothetical, and [8] Accept that the onus is on you to support your hypothetical and not for anyone else to defend the mainstream. Eight points off the top of my head that you have failed to align with. You really need to do better and stop just simply trying to get the last say in as if that will help the nonsense you are presenting. This is a science forum, not a play center.

Learn not to be so obtuse and side step relevant questions. Again...when are you going to present your evidence and/or proof that is supposed to support your illogical, unsupportable claim? Afterall, isn't that why the other thread was closed? Afterall SR and GR are 100% validated and verified with practical applications.

Ooops, yeah, my mistake. Remain silent?? My dear friend, I will continue in line with the rules to refute your nonsensical claims, and your now very obvious game of one-up-manship. I'll say it again, when are you going to present your evidence or proof to support your unsupportable claim? Today?Tomorrow?, next week? next year? I'm rather confident that if you continue with the empty rhetoric and fail with your presentation of evidence, then this thread will probably be closed. Yes, gravity is by far the primary reason the universe is the way it is, gravity as per GR. And as we all know SR is simply a subset or special case of GR. And even more importantly, if you decide to get familiar with the scientific method, you may realize that science isn't about "something tells me" but about the presentation of evidence that you are shockingly bereft of.

There are probably hundreds of kooky inspired hypothetical nonsense out there like yours. Why would they even consider it as it doesn't even tick one box? Now obviously you are still just talking about presenting your evidence, so tell me how long will this talking continue without presenting said evidence? In the meantime SR and GR stand as is, validated, verified with many practical applications, and cheap unsupported rhetorical claims such as yours, on a forum open to any Tom, Dick or Harry will in time simply be lost in cyber space.

Your posts are nothing more unsupported unevidenced rhetoric that defy observations, experimentations and the reality of applications of SR and GR. I suggest you stop acting childish and either put up or shut up with regards to your claim of having solved some non existent problem. In the meantime I will refute your nonsense as I see fit, and in line with forum rules. Found an interesting link http://spacetimecentre.org/vpetkov/courses/reid.html Conclusion I’m showing as a final slide a table that made an impression on me when I first saw it many years ago. It lists 13 key experiments that have a testing relevance to Special Relativity in the columns, and the predictions of 6 alternative theories to Special Relativity in the rows. The red boxes mark the places where the experimental results disagree with the predictions of the theory. Only Special Relativity is in agreement with all testing experiments. theory Light Propagation experiments Experiments from other fields 1 2 3 4 5 6 7 8 9 10 11 12 13 aether theories stationary aether, no contraction A A D D A A D D N A N D D stationary aether, Lorentz contraction A A A D A A A A N A N A D aether attached to ponderable bodies D D A A A A A D N N N A N emission theories original source A A A A A D D N N D N N N ballistic A N A A D D D N N D N N N new source A N A A D D A N N D N N N special relativity A A A A A A A A A A A A A Legend: A: the theory agrees with experimental results D: the theory disagrees with experimental results N: the theory is not applicable to the experiment 1: Aberration, 2: Fizeau convection coefficient; 3: Michelson-Morley; 4: Kennedy-Thorndike; 5: Moving sources and mirrors; 6: De Sitter spectroscopic binaries; 7: Michelson-Morley, using sunlight 8: Variation of mass with velocity; 9: General Mass-Energy equivalence; 10: Radiation from moving charges; 11: Muon decay at high velocity; 12: Trouton-Noble; 13: Unipolar induction, using moving magnet. much more at link http://spacetimecentre.org/vpetkov/courses/reid.html

Stop being silly. GR is our accepted, validated and verified theory of gravity, that by extension from SR, that you are trying to invalidate but failing miserably.

Again, this is off topic. If you want to discuss the long defunct Plasma or Electric universe, start another thread.

https://phys.org/news/2018-08-renovations-big-nuclear-astrophysics-lab.html In nature, the nuclear reactions that form stars are often accompanied by astronomically high amounts of energy, sometimes over billions of years. This presents a challenge for nuclear astrophysicists trying to study these reactions in a controlled, low-energy laboratory setting. The chances of re-creating such a spark without bombarding targets with high-intensity beams are unfathomably low. However, after recent renovations to its accelerator, one laboratory reported record-breaking performance. Following six years of upgrades to the Electron Cyclotron Resonance Ion Source (ECRIS) at the Laboratory for Experimental Nuclear Astrophysics, a member of the Triangle Universities Nuclear Laboratory, researchers from the University of North Carolina report improved results. In Review of Scientific Instruments, the group focused on the system's acceleration column and microwave system, making it safer and yielding better high-voltage source stability and signal-to-background ratio. "What a lot of people don't realize is that there isn't really anything that exists on the market for this that we can just buy," said Andrew Cooper, an author on the paper and one of the lead designers behind the project. "Rather than pay millions of dollars [for upgrades], we approached it as a challenge." Read more at: https://phys.org/news/2018-08-renovations-big-nuclear-astrophysics-lab.html#jCp the paper: https://aip.scitation.org/doi/10.1063/1.5024938 Development of a variable-energy, high-intensity, pulsed-mode ion source for low-energy nuclear astrophysics studies: ABSTRACT: The primary challenge in directly measuring nuclear reaction rates near stellar energies is their small cross sections. The signal-to-background ratio in these complex experiments can be significantly improved by employing high-current (mA-range) beams and novel detection techniques. Therefore, the electron cyclotron resonance ion source at the Laboratory for Experimental Nuclear Astrophysics underwent a complete upgrade of its acceleration column and microwave system to obtain high-intensity, pulsed proton beams. The new column uses a compression design with O-ring seals for vacuum integrity. Its voltage gradient between electrode sections is produced by the parallel resistance of channels of chilled, deionized water. It also incorporates alternating, transverse magnetic fields for electron suppression and an axially adjustable beam extraction system. Following this upgrade, the operational bremsstrahlung radiation levels and high-voltage stability of the source were vastly improved, over 3.5 mA of target beam current was achieved, and an order-of-magnitude increase in normalized brightness was measured. Beam optics calculations, structural design, and further performance results for this source are presented.

https://phys.org/news/2018-08-quiet-sunday-night-supermassive-black.html Earlier this year, on a quiet Sunday night, my colleague Jack and I found the fastest-growing supermassive black hole in the known universe. We were fortunate to be part of the team that made one of the greatest discoveries in astronomy this year. This supermassive black hole, or quasar, is 20 billion times the mass of our Sun and is 12.5 billion light years away from Earth. It expands 1 per cent every million years and it devours a mass equivalent to our Sun every two days. Officially, it is called SMSS J215728.21-360215.1, but we call it the hungry monster. The 'we' that made the discovery was a small team led by Australian National University astronomer Dr. Christian Wolf and his team, and included two postgraduate students from the University of Melbourne, Jack Hon and myself. Read more at: https://phys.org/news/2018-08-quiet-sunday-night-supermassive-black.html#jCp

The Plasma and/or Electric universe hypothetical was debunked many years ago, if that's what you are suggesting. Gravity is also an accumulative force and again the prime reason for solar systems, galaxies, galactic groups and walls...but this is off topic from your other nonsense that is the subject of this thread. I asked for clarification or corrections on any of my statements and claims. None was contradicted. You alone have that honour. It's all time dilation as I said, and each frame of reference is as valid and correct as any other frame. Or are you also going to show your ignorance and dispute that? Your being obtuse again. The frame of reference of a photon is totally unrealistic as everyone has told you. Side stepping that fact is as stupid as your past $50 reward nonsense. You have been contradicted and shown to be in error by all contributors to this thread. SR and GR stand as unchallenged and verified despite your claims and this so far non existent proof and/or evidence which we are all waiting for. But hey, this is all now rather boring, so I'll let you play your game of oneupmanship and have last reply before any thread closure as per your last efforts. Your delusions of grandeur facade seems inpenetrable at this time.

Gravity primarily remembering that gravity is always an attractive force and acts over long range. Sure, let's now wait for some proper professional peer review. I've already asked a few posts back, for those smarter then I, to also review my posts and claims. So far it is you that is wrong in the whole scenario you are pretending you know something about. You are being obtuse again. Let me educate you once more...BH's and DM by there very nature, can only ever be indirectly evidenced. But in actuality, with the gravitational waves discoveries of recent times, one can now say that BH's are confirmed. Or does this also offend your delusional sensibilities? And of course are never and can never be at rest. Why would I stop you? I have absolutely no qualms or objections re anyone being able to invalidate any incumbent theory. But as I have already mentioned elsewhere, the first step in invalidating any incumbent theory, is to know that theory thoroughly. You don't and thereby is the reason/s for your potential failure. Your links and pretty pictures do not impress me. Again SR and as an extension GR have both been validated and verified many thousands of times and have many real life actual applications.....not withstanding the many kooks and nuts on u tube claiming it is wrong. I may be a learner and an amateur at this game, but I still can sort out the wheat from the chaff.

Simply gravity at work...nothing more, nothing less. ?? Probably the underlying problem for you and the ignorance and error ridden posts of yours. As I have already said, you can't, you won't. This is simply pretentious bluster. If you have trouble understanding English, it isn't my fault. Again time dilation as observed is caused by speed and gravity. It's all time dilation. And yet it is you making unsupported claim and pretending you have invalidated 100 years of observation, experiment, and application. BH's have been indirectly observed and are evidenced by the observation of spacetime and matter/energy effects that surround them. DM is also indirectly evidenced by simple observations, not the least being the bullet cluster anomaly. Both by there very nature can never be directly observed so just another desperate example of you trying to support the unsupportable. Photons on the other hand, have no rest mass period. You can't and you won't...more pretentious bluster.

I wouldn't really be popularising that too much if I were you...not a good look. It doesn't need to. And obviously not withstanding your denial and pig-headiness, it still is the accepted verified reality we use everyday. Of course you do. Far easier then admitting you have been and are entirely wrong. Only in your delusional world. Well since you won't write up the paper, and since you certainly will not succeed, and since this is just more delusions of grandeur, analogous to the mythical "reward" you offered in one of your posts, my belief or otherwise is incidental. I accept reputable knowledge that has been verified and validated thousands of times, rather then the unsupported nonsensical rhetoric you are expert at. And I won't judge you: I don't need to, you have convicted yourself. As I and others have told you, there is much rubbish and nonsense on the net and your desire to be associated with that is not a good look. Vixra for example...enough said Try some reputable links and then be man enough to admit you are essentially wrong in your claims. What's even more sad, is your refusal to be able to admit your errors of judgement and silly claims, driven by delusions of grandeur and a desire for one-up-manship contest you seem to have turned this into.. There are I think around five other knowledgable people here who are refuting your claims and seeing an obvious delusional capacity. Not really:Just standing on the shoulders of giants. . In each frame of reference time will always pass at one second/second. It is only when viewed from another outside frame that time dilation takes place, and that includes time dilation caused by gravity. In each frame though, each is as valid as the other. No skin of my nose matey. But certainly the pig headiness as someone else raised stands out like dog balls. anyway I'm off and have a busy day ahead of me, rather then sitting here engaging in your delusions. bye have a good day.

The earth would continue to orbit for 8.25 minutes if the Sun should magically disappear. Analogies can be and obviously I believe are useful.eg; the rubber sheet analogy describing gravity. The danger is that all analogies have limitations and one can become confused if it is taken too far. Another analogy illustrating the expansion of the universe is a container of dough with raisins and put in the oven to bake. The dough [spacetime] expands and the raisins [galaxies] are taken along for the ride so to speak.

Relativity is a branch of physics and consists of SR as a subset or special case of GR, both of course being tested validated and verified many thousands of times. Issues you will keep on avoiding. They are innaccurate when used outside their zones of applicability. But again this is simply your way of avoiding the fact as everyone has told you, that SR and as a result GR, are entirely consistent and verified. As you have been told many times, any reference frame of the photon is really meaningless. And of course since you now "claim"to have found the solution, I take it that you will now write up a paper for professional peer review...not of course with any of the crank sites that you eagerly link to. Your first lesson in discovering/learning about science and any aspect of science, is that the Internet is filled with nonsensical claims along with the reputable ones. Again, despite your obtuseness, the twin paradox is not a paradox at all. Perhaps one of our other knowledgable participants will explain it to you No wrong again. Most all scientists realize that due to the acceleration/decelleration phase of the travelling twin, that when he or she returns to Earth, he or she will find that the stay at home twin has aged much more. Whatever "second half" you ascribe to is the crank section and in the tiniest minority. I've given you the accepted fact on what a scientific theory is and what a law is. What you actually care about as far as science is concerned is neither here nor there. It means nothing and makes no difference with the real scientific efforts being constantly practiced by the professionals and in time will be lost in cyber space, as obviously you have no intention of writing up any paper for any potential professional review. SR and GR are well supported and verified theories, as opposed to wild arse guesses and baseless hypotheticals that you are pushing. You have both the official definition of a scientific theory and a physical law. That trumps whatever made up fairy tale version you wish to incorporate rather then admit you have been wrong from go to whoa. Or maybe you are continuing with being obtuse, or as another ha said, remain pig-headed in the face of evidence against your nonsense. Again time dilation can be caused by either relativistic speeds and/or gravitation. Both are real effects as well as being relative. Here's your free lesson. Time and space are not absolute, while the speed of light is absolute or invariant. Go it? Your knowledge on both is askew to put it as nice as possible and defies the reality in the scientific world, that both SR and GR are validated and verified accepted theories/models of the reality around us and put to practical uses everyday. Best of luck!!! I'll let others more attuned to the finer points of SR to answer your question.

No, wrong again. They are scientific disciplines or catagories. Didn't I just say that? Which again means that neither Newtonian, SR or GR is wrong and each have their own zone of applicability..sheesh! Fail again, since the so called "twin paradox"is not really a paradox. So you make up your own definitions and meanings as you go? Got it, and that's why you fail and are wrong. No theories they are and theories they remain. For obvious reasons imbedded in the scientific method. A scientific theory is NOT a wild guess. It must be consistent with known experimental results and it must have predictive power. As new knowledge is gained, theories are refined to better explain the data. A law is a mathematical relationship that is consistently found to be true. from WIKI: They are aspects of particular theories. Time dilation is caused by either speed or gravity The doppler effect is real enough. But your error comes to the fore by not recognising and/or accepting when cosmological and gravitational effects come into play