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Showing content with the highest reputation on 05/12/19 in all areas

  1. So you would ignore the advice of doctors if you were seriously ill? However, it is refreshing to have someone admit to being completely closed-minded; it is usually an accusation aimed at others.
    2 points
  2. Isn't it also more accurate to say that the molten core is what allows the flow of nickel and iron to produce our magnetic field? The field can't drive (produce) the molten core if the movement of the core is required to produce the field.
    1 point
  3. This is just an assertion. And what does "electromagnetism" mean? What units is it measured in? What does "form" mean? And how is it measured? This is not evidence, it is just an assertion. You need to use your "equations" to calculate the magnitude of the effects you are claiming, and then show that these predictions match what we observe better than existing theories. Can you do that?
    1 point
  4. Were you never a baby? We can't all grow out of it...
    1 point
  5. Remarkably specious and certainly without basis in science and study of the aging. Quite the contrary, one may find several studies and articles, some scholarly, on how routines that show "pensioners" (i.e., aging) who engage social and physical activities away from home are actually more healthy, have a better quality of life and, thereby, are much safer than those who stay home. Faith, as I've found, services the insecure who seem without courage to face the unknown and unfathomable without a virtual parent holding their tiny hands throughout their adult life. Life is inevitable and one should be willing and able to confront its uncertainties resolutely without the veil of some immaterial force that offers no real protection beyond one's own imagination--IMO.
    1 point
  6. If you don't want to discuss, then why come to a discussion site and post in the first place? You, sir, are avoiding the issue. No it meant that you either did not understand or avoided what I said about symmetry, in order that you can claim symmetry to be synonymous with regularity, which it is not. I gave you one example of something irregular, yet possessing symmetry. I will repeat it more generally. Take any irregular shape and reflect it in an axis. You now have a symmetrical irregular shape. Point proven. They are different.
    1 point
  7. To a good approximation; nothing ever fails in straight compression. You may find this next equation helpful. The (average) force exerted by an object when it comes to a halt is equal to the (average) force used to accelerate it times the ratio of the distance it was accelerated to the distance over which it stops. So, if I drop a rock that weighs 1 newton off a table that's a metre high and it comes to a halt when it hits the carpet which is 1 cm thick, the average force on the floor is 100N. It's also important to recognise that the "strength" (however you measure it) of the object which strikes a target isn't as important as people think. You can cut steel with water if the water is moving fast enough.
    1 point
  8. In my view the renewed passion for going back to the moon is on shaky ground. My views on this are not secret - that I think there is no economic basis for such ventures and that without it it will struggle to be more than a feel good exercise in nationalist pride building through showcasing aerospace capabilities . It will be very, very difficult, dangerous, expensive and won't advance grand space dreams or advance humanity on Earth in any substantial way. If it does happen it will be reliant on continuing subsidised supply lines with transport costs that, even optimistically, be astronomical; it will still be multi-million US$ per ton to reach the Moon. The capital costs of a functional launch facility that can turn around, refuel and repair re-usable rockets is, well, astronomical. No mining will make sense except to reduce the huge costs for the most basic things like water and air - and if the most basic things are such a big deal the prospects of things growing from there are slim indeed.
    1 point
  9. Here is another article with relation to heavier elements..... https://phys.org/news/2019-05-collapsar-accretion-disks-source-heaviest.html Researchers suggest collapsar accretion disks might be source of heaviest elements: A trio of researchers at Columbia University is suggesting that collapsar accretion disks might be the major source of the heaviest elements. In their paper published in the journal Nature, Daniel Siegel, Jennifer Barnes and Brian Metzger describe their study of the accretion disks that form as neutron stars collapse into black holes, and what they found. extract: Prior research has suggested that the heaviest elements were created by what is known as the "r-process," in which a chain reaction results in atomic nuclei absorbing neutrons. Astrophysicists had theorized that two neutron stars colliding would likely give way to the conditions necessary for the r-process to occur, creating some of the heaviest elements. Two years ago, the team credited with observing the first gravity waves reported the effects of two neutron stars colliding. Subsequent study of the event showed that it was likely that the r-process had occurred, giving strong credence to the theory. But there was still one problem. The collision of neutron stars is a rare event—too rare to account for the amount of the heaviest elements that exist today. That led the researchers to consider other neutron star activities—such as their gravitational collapse. more at link...... and the paper: https://www.nature.com/articles/s41586-019-1136-0 <<<<<<<<<<<<<<<<<<<<<<<<<<<<>>>>>>>>>>>>>>>>>>>>>>>>>>>>>> and an earlier article from 2018 on the same process possibilities..... https://physicstoday.scitation.org/doi/10.1063/PT.3.3815 extract: "The remainder of the chemical elements, except for a tiny amount of lithium, were forged in stellar interiors, supernova explosions, and neutron-star mergers. Elements up to and including iron are made in the hot cores of short-lived massive stars. There, nuclear fusion creates ever-heavier elements as it powers the star and causes it to shine. Elements heavier than iron—the majority of the periodic table—are primarily made in environments with free-neutron densities in excess of a million particles per cubic centimeter. The free neutrons, if captured onto a seed nucleus, result in a heavier, radioactive nucleus that subsequently decays into a stable heavy species. The so-called slow neutron-capture process, or s-process, mostly occurs during the late stages in the evolution of stars of 1–10 solar masses (M⊙). But the s-process accounts for the formation of only about half of the isotopes beyond iron. Creating the other half requires a rapid capture sequence, the r-process, and a density of greater than 1020 neutrons/cm3 that can bombard seed nuclei. The requisite neutron fluxes can be provided by supernova explosions (see the article by John Cowan and Friedrich-Karl Thielemann, Physics Today, October 2004, page 47) or by the mergers of binary neutron-star systems". and relevant to Swansont's comment...... "Nuclear physicists are still working to model the r-process, and astrophysicists need to estimate the frequency of neutron-star mergers to assess whether r-process heavy-element production solely or at least significantly takes place in the merger environment." the article then goes on to say..... "To test r-process models, nuclear physicists will need to obtain measurements or solid predictions of the fundamental properties of heavy, unstable nuclei that lie far from the valley of stability occupied by familiar long-lived isotopes—they’ll need to know, for example, about masses, nuclear interaction cross sections, and decay rates. Procuring such data is a primary science driver for several international accelerator facilities. The US representative, the Facility for Rare Isotope Beams, is currently under construction at the campus of Michigan State University and is expected to be completed in 2022". :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::: Excellent article and far more informative then the latter article in the OP!! Associated references from the above article.... https://science.sciencemag.org/content/358/6370/1570 Early spectra of the gravitational wave source GW170817: Evolution of a neutron star merger https://science.sciencemag.org/content/358/6370/1574 Early spectra of the gravitational wave source GW170817: Evolution of a neutron star merger https://iopscience.iop.org/article/10.1088/0004-637X/814/1/58/meta MERGER RATES OF DOUBLE NEUTRON STARS AND STELLAR ORIGIN BLACK HOLES: THE IMPACT OF INITIAL CONDITIONS ON BINARY EVOLUTION PREDICTIONS :::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::::
    1 point
  10. Here is another article on this concept of Planetary Migration... https://phys.org/news/2019-05-gravitational-protoplanetary-disks-super-earths-stars.html Gravitational forces in protoplanetary disks may push super-Earths close to their stars: The galaxy is littered with planetary systems vastly different from ours. In the solar system, the planet closest to the Sun—Mercury, with an orbit of 88 days—is also the smallest. But NASA's Kepler spacecraft has discovered thousands of systems full of very large planets—called super-Earths—in very small orbits that zip around their host star several times every 10 days. Now, researchers may have a better understanding how such planets formed. A team of Penn State-led astronomers found that as planets form out of the chaotic churn of gravitational, hydrodynamic—or, drag—and magnetic forces and collisions within the dusty, gaseous protoplanetary disk that surrounds a star as a planetary system starts to form, the orbits of these planets eventually get in synch, causing them to slide—follow the leader-style—toward the star. The team's computer simulations result in planetary systems with properties that match up with those of actual planetary systems observed by the Kepler space telescope of solar systems. Both simulations and observations show large, rocky super-Earths orbiting very close to their host stars, according to Daniel Carrera, assistant research professor of astronomy at Penn State's Eberly College of Science. more at link...... the paper: https://academic.oup.com/mnras/article-abstract/486/3/3874/5432363?redirectedFrom=fulltext Formation of short-period planets by disc migration: ABSTRACT: Protoplanetary discs are thought to be truncated at orbital periods of around 10 d. Therefore, the origin of rocky short-period planets with P < 10 d is a puzzle. We propose that many of these planets may form through the Type-I migration of planets locked into a chain of mutual mean motion resonances. We ran N-body simulations of planetary embryos embedded in a protoplanetary disc. The embryos experienced gravitational scatterings, collisions, disc torques, and dampening of orbital eccentricity and inclination. We then modelled Kepler observations of these planets using a forward model of both the transit probability and the detection efficiency of the Kepler pipeline. We found that planets become locked into long chains of mean motion resonances that migrate in unison. When the chain reaches the edge of the disc, the inner planets are pushed past the edge due to the disc torques acting on the planets farther out in the chain. Our simulated systems successfully reproduce the observed period distribution of short-period Kepler planets between 1 and 2 R⊕. However, we obtain fewer closely packed short-period planets than in the Kepler sample. Our results provide valuable insight into the planet formation process, and suggests that resonance locks, migration, and dynamical instabilities play important roles in the formation and evolution of close-in small exoplanets.
    1 point
  11. I assume you mean the general development of models (which are mathematical) of something which is not, such as a mathematical model of heat loss from a building. As opposed to physical models of something mathematical as in orgami, stellated dodecaherons etc? (That would be Mathematical models by Cundy and Rollet) So A gentle introduction Mathematical Modelling Berry and Houston Edward Arnold More advanced (University level) Macmillan Guide to Mahtematical Modelling Edwards and Hanson Macmillan Most advanced Mathematics of Models - continuous and discrete systems Griffiths and Oldknow Ellis Horwood After this you will need to look in subject specialist books (usually a particular engineering subject, but also statistics.) Does this help?
    1 point
  12. I know that everything traveling faster than the speed of light since the big bang is not part of the model. You said speed of light was!?!? https://en.wikipedia.org/wiki/Shape_of_the_universe I googled and found 5 pages!?!!? You obviously are not even reading my posts or your reading comprehension is really bad! Obviously you didn't google, "shape of the Universe," which makes you a troll and a waste of my time! Later...or not!
    -1 points
  13. Now why would I post it here only mattering to me when it's already jotted down in my mind? People, better yet nobody in this world sways my decisions about anything. In what they say or say they feel.
    -1 points
  14. Perhaps you may Cite evidence to support your statement : "Perhaps not with nature, but "most" certainly do...seems to be a natural process with journalism. "? Should be fairly easy, since "..."most" certainly do..." as you stated. And, No, I cannot agree "that the expertise on this forum in general, are always quick to highlight or dispute any wrong or false conclusion from any article and the journalism portrayed within. " Obviously? I did not compare "a basically science news site as is "physorg," with a science paper publishing company publishing peer reviewed articles as is "nature" ". I did not mention any "science news site ". I did not even mention "physorg", and no "physorg" Links have been posted in this Thread. I am not sure what you are trying to convey when you state : "I mostly include both as both give relevant outlines of the relevant news item I'm posting." Maybe you could provide Links to your Posts where you "mostly include both as both give relevant outlines of the relevant news item I'm posting." ?
    -1 points
  15. Like I said I'm not swayed into making a decision on what another one says, like you in this instance, go ahead and remain ignorant in your thinking cause I can make decisions on my own by what I perceive to be good and in my best interest. How ignorant it is to make a decision based on what others think. For the record you haven't a clue about who I am and what I know. Now run along. Immature and dont esentially know squat about life. Now you run along too.
    -1 points
  16. Oops ran out of edits! Electromagnetism X motion X form = everything So the, "form," part of this is size of the given particle or planetary body. Both, "form," and "motion," then we can measure. We also know Energy = acceleration squared (the speed of light) E=MC squared So the only variable here is friction. Friction would be in direct relation to, "Form," (size of the particle or planetary body). In the hypothetical Universal universes there would be layered friction. The other intersecting universes, our expanding universe, the galaxy motion, and those parts the sun doesn't protect us from and even our orbit and rotation. edit: This friction could also be the, "dark energy," just as all the intersection universes are the missing, "dark matter."
    -1 points
  17. And I can tell when someone is lying before they open their mouth.
    -2 points
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