

beecee
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Everything posted by beecee
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My apologies for again butting into this engrossing debate....... Agreed, though sometimes a realistic observation. Again agreed. Yep, times change as do expectations of what is acceptable or what isn't. But my main reason for butting in, is that what was said, "stupid woman" was said under a person's breath, and it was the technology of the day that caught him out. We most certainly cannot curtail what anyone of us think, and all of us, yes all of us, have at times had "offensive" thoughts of others...havn't we?
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No, it's an argument from observation. And that's just as it should be. Models such as our present model for the evolution of the universe/space/time, up to the formation of planetary bodies and stars, are overwhelmingly supported and observed, and would certainly need some extraordinary observational or experimental evidence to invalidate. Likewise, the confirmations and valid predictability of SR and GR will obviously be hard to overthrow. Or more to the point, you have no evidence whatsoever to support your hypothetical claims. The onus is on you to [1] show the incumbent model as invalid, and [2] To offer some evidence to support your hypothetical. You have done neither. In fact your claim that your hypotheticals are rejected just because they are different, is shown to be nonsense by history itself. Perhaps more to the point, is that you are opposing it just for opposition sake, or perhaps to align with some mythical biblical parable. OK, please then again, [1] list the points of mainstream cosmology that you see as wrong, and tell us why, [2] List the points you propose to replace what you see as errors in the mainstream, and [3] What evidence do you have to support your hypothetical? Your whole OP showed a total lack of scientific research, learning and observation in my very humble opinion.
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The problem I find with those promoting alternative models on science forums such as this, , is that invariably they are somewhat ignorant of the incumbent model, that has already "run the gauntlet" so to speak, and aligns with current observations and understandings and contrary to your erroneous claim, most certainly does pass muster. The current accepted model of the expanding universe, is the least complicated of all the models, that explains and aligns with present observational data, with the greatest precision. While certainly some models maybe "less" complicated, they invariably fail to explain all that the incumbent model does, or are based on, or include some aspect which can best be described as lunacy in this day and age and more then likely based on pseudoscience or mythical biblical parables. Bingo!
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The simple cause of cosmic inflation (Big Bang, Expansion of Space)
beecee replied to 810's topic in Speculations
I won't argue with that, other then to point out that both Inflation and the BB, refer to the Observable universe only, something to remember when you refer to your singularity and any dimensionless dot.. http://www.astro.ucla.edu/~wright/infpoint.html What evidence do you have to support this "energy wave" concept? How does mass cause any "energy wave"? I once had put to me that instead of the universe expanding, perhaps our rulers are shrinking...a fabricated diametrically opposite scenario in my opinion. I would have a number of arguments against that, including "Occam's Razor" Except in totally diametrically opposed methodology. Again, the data tells us that the universe was totally opaque up to around 385,000 years post BB. When temperatures had cooled enough, [5000 K?] electrons started to couple with atomic nuclei and the universe became transparent...After this blast of light, the universe went dark again, but still transparent, and remained so until the first stars started to form. We see that first light today in the CMBR at 2.73K. Your "went dark again" did not appear to be talking about post recombination. That makes no sense. You are saying that stellar objects and remnants came before space and time! Astronomers/Cosmologists have a reasonable picture of how our universe evolved from t+10-43 seconds, up until today, while admittedly less certain of the process, the closer to the BB we go. Space and time evolved first [interchangeable according to GR] along with the Superforce, or the early period when all the four known forces were combined into one. As temperatures and pressures started to drop with the expansion of space and time [N.B. no stars or any matter as yet] the superforce started to decouple, gravity first. This caused phase transitions and false vacuums, and the excesses of energy went into creating our first fundamental particles such as electrons, quarks etc. Three minutes later protons and neutrons...385,000 years later, the first elements of Hydrogen, Helium....the rest is history. I believe that summation likely scenario, and as supported in particle accelerators etc, puts a hole in your hypothetical "diametrically opposed" hypothetical. Bingo, and well put! -
Refraction verses reflected verses acceleration?
beecee replied to jajrussel's topic in Classical Physics
It certainly changes speed from one medium to another, so technically, your assumption is probably correct. A change in frequency, not speed, as light follows the geometry of spacetime. Of course it follows the geodesic of that spacetime, but also a change in speed as it enters the medium of water, from the near vacuum of space and/or vice-versa. -
Refraction verses reflected verses acceleration?
beecee replied to jajrussel's topic in Classical Physics
OK, the process of reflection of light/photons is simply light being turned back from a reflective surface, so that the angle of incidence equals the angle of reflection. Refraction occurs when light passes from one medium to another of a different density and obviously different speed. Your other query re light following geodesics in spacetime, pertains to a vacuum or near vacuum, and thus is different from reflection and/or refraction. -
The simple cause of cosmic inflation (Big Bang, Expansion of Space)
beecee replied to 810's topic in Speculations
I missed that. Firstly, matter is not trapped within any gravity well...Matter simply alters the geometry of spacetime, and we feel that geometrical alteration/curvature as gravity. The matter [eg a star] can move through spacetime and in doing so, is continually altering the regions of spacetime as it goes. Secondly, Space is not pushing, it simply exists, and is expanding over large scales. Light of course simply follows geodesics in spacetime, and explains the effects of gravitational lensing and such that we observe. -
The simple cause of cosmic inflation (Big Bang, Expansion of Space)
beecee replied to 810's topic in Speculations
We know nothing of the moment of the BB. In fact the BB is simply the overwhelmingly supported model of space and time evolving from t=10-43 seconds. What expansion of space do you envisage within our own local group of galaxies? M31 for example shows a blue shift because it is moving towards us. Please show me how any space expansion is occurring if we observe it moving towards us? Again, regions of heavy mass/energy densities, has the effects of gravity overcoming, or decoupling us from the overall large scale expansion of space. Because the universe was always opaque until around 385,000 years post BB, or until temperatures had fallen sufficiently to enable electron coupling to atomic nuclei. No "went dark" at all. No, DE is not being emitted by stars of any sort. DE is simply what is causing space to expand, and the universe to be getting bigger, and is acting in opposition to gravity. Stars of course do cause spacetime curvature and as a result gravity, which acts in opposition to DE. The question of time is more philosophical then scientific. But what we do know tells us that time will always pass, and that motion [which you seem obsessed with as others do] is just a change in position, with respect to the passing of time. And again, we know nothing of moment 000, or even 0. https://www.youtube.com/watch?v=MAScJvxCy2Y In relation to your other rhetoric, let me quote one of the greats...."I see as far as I do, because I stand on the shoulders of giants" I suggest you do some research. Any physical singularity, involves infinities, such as infinite spacetime curvature [BH's and infinite densities [BH's and the BB] and as a result most reputable physicists abhore such singularities and reject such absurdities. The singularities so often defined, are simply singularities where our current laws of physics and GR cannot be applied...such as the center of BH's and the moment of the BB, or the quantum/Planck levels in which they occupy. What that then suggests is a surface of sorts, that we are unable to define, should exist at those levels. But that is admittedly speculative. I have yet to meet any Mother, that did not believe her own child was the most adorable. -
Simply, it is the law of conservation that is being enforced...the possibility exists that the positive escaping particle becoming real, and the virtual particle falling in is negative, thereby subtracting from the overall mass of the BH.
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Could Black Holes be the hottest things in the Universe?
beecee replied to coderage9100's topic in Astronomy and Cosmology
A Kerr BH, that is a spinning BH, will effectively have two horizons...the EH proper, and the static horizon, or static limit, which marks the boundary of spacetime that has been geometrically altered due to the angular momentum, much as the Earth is oblate due to its angular momentum or rotation. Between the static limit/horizon and the EH proper, it is theoretically possible to extract energy for a sufficiently advanced civilisation, and matter caught within this region is dragged around with space, as per frame dragging effect. Once the EH proper is reached, everything is back to what is normally envisaged with a BH...that is once any matter crosses that EH, it has only a one way path to the center. Another point I'm not that familiar with is a so called "Cauchy horizon" or inner horizon, within the EH proper of the BH, and as best as I am able to describe, is a closed timelike curve. Mordred, Strange or one of our other renowned knowledge tanks may like to define that better then I am able to. -
Just butting in here, isn't calling someone a "stupid woman" be possibly factual, the same as calling someone a "stupid man". Yes certainly offensive to the recipient. Where it becomes sexist is saying, "stupid women" or alternatively "stupid men"....yes, yes OK, perhaps calling her a "stupid person" may have been more diplomatic? I now hand control back.
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Marking a thread as "Solved" is certainly helpful, but in many situations, some newbie or even oldie, still maybe confused or have some issue re some aspect of a solved answer. So yes, marked "solved" but without closing at least within a certain time limit....say 6 months? Bingo! We have seen some threads resurrected after being dead for literally years.
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Other then those personal opinions, I'm all for the slogan.
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I am far more offended by the many religious supporters, mounted on white chargers, conducting never ending crusades against the so called evils of science. Perhaps the point you are trying to make is the forthright "apparent" abrasive nature of people such as Hitchens and Dawkins. Personally, I see the more "dulcet tones" of the likes of the late great Carl Sagan as far more productive.
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The simple cause of cosmic inflation (Big Bang, Expansion of Space)
beecee replied to 810's topic in Speculations
Not really. Space is what exists between you and me at this time. The reason why space expands, we are not really sure, but that same expansion can be "nullified" by local regions of high mass/energy densities and the resultant gravity. Wrong again...the universe was opaque for at least around 385,000 years after the BB due to the the scattering of photons before recombination, and until temperatures had dropped far enough to enable electrons to couple with atomic nuclei. Expansion slowed and continue to slow up until around 5 billion years ago, as a result of mass/energy densities of the then universe. As that mass/energy density lessened with continued expansion, acceleration in that expansion became evident, except for isolated regions of high mass/energy densities such as our local group of galaxies. The impetus behind the continuing acceleration is unknown and is what we determine as DE. Actually stars congregated into systems, galaxies, groups of galaxies, and great walls of galaxies under gravity, with expansion only evident over large scales. Not at all. When Einstein first formulated GR, the prevailing thought at that time was that the universe was static...no mention of time stopping at all. Time more accurately is simply the intervals between sequential events. Both time and space of course also depends on one's frame of reference. Most Physicists today do not accept that singularities exist, [super duper or otherwise] other then as defined by where our laws of physics and GR do not apply. That is the quantum/Planck level. No, it is exactly that...unsupported speculation. If I had a dollar for every "would be if he could be" that claimed he had some new "theory" that debunked a supported incumbent model, I would be a rich man. It is/was obvious to all why it was moved to the speculation section, and that was because it was speculation. The "point of view" you claim, is not a "point of view" rather it is the accepted model based on observational evidence that explains what we observe. That model may change in the future as further observations are made, or it may continue to be re-enforced. -
https://newatlas.com/brightest-quasar-600-trillion-suns/58020/ From our point of view here on Earth, the brightest object in the sky is unquestionably the Sun. But this unremarkable star is a mere 10-watt bulb compared to quasars, extremely luminous galactic cores that shine so intensely thanks to their ravenous hunger for nearby material. Now, astronomers have detected the brightest quasar ever found, shining with the light of almost 600 trillion Suns. The quasar, officially designated J043947.08+163415.7, pips the previous brightness records by a fair margin. Until now the title belonged to a quasar shining with the equivalent of 420 trillion Suns, while the most luminous galaxy found so far is "only" as bright as 350 trillion...more at link <<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> the paper: http://iopscience.iop.org/article/10.3847/2041-8213/aaf86a Most Lensed Quasars at z > 6 are Missed by Current Surveys: Abstract The discovery of the first strongly lensed (μ ≈ 50) quasar at z > 6 (J0439+1634) represents a breakthrough in our understanding of the early universe. We derive the theoretical consequences of the new discovery. We predict that the observed population of z > 6 quasars should contain many sources with magnifications μ 10 and with image separations below the resolution threshold. Additionally, current selection criteria could have missed a substantial population of lensed z > 6 quasars, due to the contamination of the drop-out photometric bands by lens galaxies. We argue that this predicted population of lensed z > 6 quasars would be misclassified and mixed up with low-z galaxies. We quantify the fraction of undetected quasars as a function of the slope of the bright end of the quasar luminosity function, β. For β 3.6, we predict that the undetected lensed quasars could reach half of the population, whereas for β 4.5 the vast majority of the z > 6 quasar population is lensed and still undetected. This would significantly affect the z > 6 quasar luminosity function and inferred black hole mass distributions, with profound implications for the ultraviolet, X-ray, and infrared cosmic backgrounds and the growth of early quasars.
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Thanks Strange. This whole aspect actually shows totally how ridiculous are the many claims of stubbornness by science and scientists, by those pushing non mainstream or alternative issues, notably of course, when their own version/take is shown to be questionable. Certainly also, if any criticism can be leveled at science at times, it would be over enthusiasm and prematurely claiming before sufficient research into the accuracy of such results, as per the BICEP2 results. Noting of course, that it was science itself and the Planck contingent that showed those results to be contaminated. Obviously and correctly, this was foremost in the minds of those involved with aLIGO and the time it took for the final analysis of the first gravitational waves discoveries to be released publicly.
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A list of valid points from your post, that I believe no one can argue with, with any real sincerity. And as it should be. Vinaka vakalevu again Mordred.
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Nonsense, new "unsupported" ideas are as you say, unsupported....Why would anyone entertain any unsupported idea, particularly when the proposer of that idea, is inevitably claiming it as superior to an incumbent, well supported theory.
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Agreed, [other then your time frame], and I don't believe anyone has indicated its a totally done deal one way or the other. GR is the accepted incumbent model still and it will require extraordinary evidence supporting any other model to change that. Just as I said, and you have iterated, we'll all sit back and wait and let the professional experts work things out. That's more along the time frame line I would have envisaged. Thanks for the input. Let's hope that I can also add the thoughts of other experts I have E-mailed to your own expertise. I found two more papers that you may like to comment on quickly, specifically for my own edification...My apologies for adding to your workload! https://arxiv.org/pdf/1802.03306.pdf On the Potential Observation of False Deviations from General Relativity in Gravitational Wave Observations from Binary Black Holes: 9 Feb 2018: Detections of gravitational waves emitted by binary black holes allow for tests of General Relativity in the strong-field regime. In particular, deviations from General Relativity can be observed by comparing incoming signals to waveform templates that include parametrized deviations from General Relativity. However, it is essential that the General Relativity sector of these templates accounts for all predictable physics. Otherwise, missing physics might be mimicked by the “beyond General Relativity” sector of the templates, leading the analysis to report apparent deviations from General Relativity. Current parametrized tests implement templates that omit physical phenomena such as orbital eccentricity and higher-order modes. In this paper, we show how the omission of higher modes can lead to false deviations from General Relativity when these effects are strong enough. We study the extent of these deviations as a function of the mass ratio and the orbital orientation. We find that significant false deviations can arise when current tests are performed on signals emitted by asymmetric binaries whose orbital angular momentum is orthogonal to the line-of-sight. We estimate that the Advanced LIGO-Virgo network operating at its design sensitivity can observe false violations with a significance above 5σ as often as once per year. Similar results are expected for other tests of General Relativity that use modified waveform models. Hence, we stress the necessity of accurate waveform models that include physical effects such as higher-order modes to trust future tests of General Relativity. <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>> and this..... https://arxiv.org/pdf/1807.02123.pdf Measuring stochastic gravitational-wave energy beyond general relativity: 5 Jul 2018: Gravity theories beyond general relativity (GR) can change the properties of gravitational waves: their polarizations, dispersion, speed, and, importantly, energy content are all heavily theory dependent. All these corrections can potentially be probed by measuring the stochastic gravitational wave background. However, most existing treatments of this background beyond GR overlook modifications to the energy carried by gravitational waves, or rely on GR assumptions that are invalid in other theories. This may lead to mistranslation between the observable cross-correlation of detector outputs and gravitational-wave energy density, and thus to errors when deriving observational constraints on theories. In this article, we lay out a generic formalism for stochastic gravitational wave searches, applicable to a large family of theories beyond GR. We explicitly state the (often tacit) assumptions that go into these searches, evaluating their generic applicability, or lack thereof. Examples of problematic assumptions are: statistical independence of linear polarization amplitudes; which polarizations satisfy equipartition; and which polarizations have well-defined phase velocities. We also show how to correctly infer the value of the stochastic energy density in the context of any given theory. We demonstrate with specific theories in which some of the traditional assumptions break down: Chern-Simons gravity, scalar-tensor theory, and Fierz-Pauli massive gravity. In each theory, we show how to properly include the beyond-GR corrections, and how to interpret observational results
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Recent research suggests this.......
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While waiting for a couple of more E-Mail replies, I found another paper detailing GW150914...................... https://arxiv.org/pdf/1602.03841v2.pdf Tests of general relativity with GW150914: 9 Jun 2016 The LIGO detection of GW150914 provides an unprecedented opportunity to study the two-body motion of a compact-object binary in the large velocity, highly nonlinear regime, and to witness the final merger of the binary and the excitation of uniquely relativistic modes of the gravitational field. We carry out several investigations to determine whether GW150914 is consistent with a binary black-hole merger in general relativity. We find that the final remnant’s mass and spin, as determined from the low-frequency (inspiral) and high-frequency (post-inspiral) phases of the signal, are mutually consistent with the binary black-hole solution in general relativity. Furthermore, the data following the peak of GW150914 are consistent with the least-damped quasi-normal mode inferred from the mass and spin of the remnant black hole. By using waveform models that allow for parameterized general-relativity violations during the inspiral and merger phases, we perform quantitative tests on the gravitational-wave phase in the dynamical regime and we determine the first empirical bounds on several high-order post-Newtonian coefficients. We constrain the graviton Compton wavelength, assuming that gravitons are dispersed in vacuum in the same way as particles with mass, obtaining a 90%-confidence lower bound of 1013 km. In conclusion, within our statistical uncertainties, we find no evidence for violations of general relativity in the genuinely strong-field regime of gravity.
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Not sure if this has been posted before....... https://arxiv.org/pdf/1811.00364.pdf Dated: November 20, 2018 The recent discovery by Advanced LIGO and Advanced Virgo of a gravitational wave signal from a binary neutron star inspiral has enabled tests of general relativity (GR) with this new type of source. This source, for the first time, permits tests of strong-field dynamics of compact binaries in presence of matter. In this paper, we place constraints on the dipole radiation and possible deviations from GR in the post-Newtonian coefficients that govern the inspiral regime. Bounds on modified dispersion of gravitational waves are obtained; in combination with information from the observed electromagnetic counterpart we can also constrain effects due to large extra dimensions. Finally, the polarization content of the gravitational wave signal is studied. The results of all tests performed here show good agreement with GR. CONCLUSIONS: Using the binary neutron star coalescence signal GW170817, and in some cases also its associated electromagnetic counterpart, we have subjected general relativity to a range of tests related to the dynamics of the source (putting bounds on deviations of PN coefficients), the propagation of gravitational waves (constraining local Lorentz invariance violations, as well as large extra dimensions), and the polarization content of gravitational waves. In all cases we find agreement with the predictions of GR. The upcoming observing runs of the LIGO and Virgo detectors are expected to result in more detections of binary neutron star coalescences [84]. Along with electromagnetic observations, combining information from gravitational wave events (including binary black hole mergers) will lead to increasingly more stringent constraints on deviations from general relativity [25, 26], or conceivably potential evidence of the theory’s shortcomings.-
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Speaking as an outsider looking in, I can't find anything better then "crazy" to describe what is happening. Perhaps what Trump means by "making America great again" is taking it back to the middle ages. Next it will be build a wall around the continental USA to keep the rest of us out, friend and foe alike....sheesh! Like I said, crazy! Perhaps a dome!!!! Apologies for making light of a serious situation.