Posted on 11/06/2018 11:51:00 AM PST by ETL
The Universes first stars after the Big Bang would have consisted entirely of elements like hydrogen, helium, and small amounts of lithium.
Those stars then produced elements heavier than helium in their cores and seeded the Universe with them when they exploded as supernovae.
The next generation of stars formed from clouds of material laced with those metals, incorporating them into their makeup.
The metal content, or metallicity, of stars in the Universe increased as the cycle of star birth and death continued.
2MASS J18082002-5104378 B, also known as Gaia DR2 6702907209758894848 B, is unusual because unlike other stars with very low metal content, it is part of the Milky Ways thin disk the part of the Galaxy in which our own Sun resides.
This star is maybe one in 10 million. It tells us something very important about the first generations of stars, said lead author Dr. Kevin Schlaufman, a researcher at the Johns Hopkins University.
The extremely low metallicity of 2MASS J18082002-5104378 B indicates that, in a cosmic family tree, it could be as little as one generation removed from the Big Bang.
Indeed, it is the new record holder for the star with the smallest complement of heavy elements it has about the same heavy element content as the planet Mercury. In contrast, our Sun is generations down that line and has a heavy element content equal to 14 Jupiters.
Astronomers have found around 30 ancient ultra metal-poor stars with the approximate mass of our Sun. 2MASS J18082002-5104378 B, however, is only 14% the mass of the Sun.
The star is a tiny, almost invisibly faint secondary member in the binary system 2MASS J18082002-5104378.
Dr. Schlaufma and colleagues found it after another group of astronomers discovered the much brighter primary star.
(Excerpt) Read more at sci-news.com ...
From the Casimir effect, we know that when two plates are placed very close to each other in a vacuum, they attract each other because the pressure of the quantum fluctuations that press on the two plates outer surfaces outweigh the quantum fluctuations on the inner surfaces.
Imagine two celestial bodies in a deep space.
The closer they get, the more the quantum fluctuations in between them get outweighed by quantum fluctuations not in between them.
Is gravity a partial product of the Casimir effect? Thus, is gravity the partial macro effect of electromagnetism/quantum fluctuations?
To understand the Casimir Effect, one first has to understand something about a vacuum in space as it is viewed in quantum field theory. Far from being empty, modern physics assumes that a vacuum is full of fluctuating electromagnetic waves that can never be completely eliminated, like an ocean with waves that are always present and can never be stopped. These waves come in all possible wavelengths, and their presence implies that empty space contains a certain amount of energyan energy that we cant tap, but that is always there.
Now, if mirrors are placed facing each other in a vacuum, some of the waves will fit between them, bouncing back and forth, while others will not. As the two mirrors move closer to each other, the longer waves will no longer fitthe result being that the total amount of energy in the vacuum between the plates will be a bit less than the amount elsewhere in the vacuum. Thus, the mirrors will attract each other, just as two objects held together by a stretched spring will move together as the energy stored in the spring decreases.
This effect, that two mirrors in a vacuum will be attracted to each other, is the Casimir Effect. It was first predicted in 1948 by Dutch physicist Hendrick Casimir. Steve K. Lamoreaux, now at Los Alamos National Laboratory, initially measured the tiny force in 1996.
It is generally true that the amount of energy in a piece of vacuum can be altered by material around it, and the term Casimir Effect is also used in this broader context. If the mirrors move rapidly, some of the vacuum waves can become real waves. Julian Schwinger and many others have suggested that this dynamical Casimir effect may be responsible for the mysterious phenomenon known as sonoluminescence.
One of the most interesting aspects of vacuum energy (with or without mirrors) is that, calculated in quantum field theory, it is infinite! To some, this finding implies that the vacuum of space could be an enormous source of energycalled zero point energy.
But the finding also raises a physical problem: theres nothing to stop arbitrarily small waves from fitting between two mirrors, and there is an infinite number of these wavelengths. The mathematical solution is to temporarily do the calculation for a finite number of waves for two different separations of the mirrors, find the associated difference in vacuum energies and then argue that the difference remains finite as one allows the number of wavelengths to go to infinity.
Although this trick works, and gives answers in agreement with experiment, the problem of an infinite vacuum energy is a serious one. Einsteins theory of gravitation implies that this energy must produce an infinite gravitational curvature of spacetimesomething we most definitely do not observe. The resolution of this problem is still an open research question.
https://www.scientificamerican.com/article/what-is-the-casimir-effec/
Theorist suggests a way to test gravitational Casimir attraction
March 4, 2015
Bob Yirka, Phys.org
Read more at: https://phys.org/news/2015-03-theorist-gravitational-casimir.html#jCp
You talk about the theory of the Casimir Effect with mirrors in a vacumn and do your equations, but you still don't know what gravity is. There could be another physics answer to the mirrors. You brilliant minds just don't know so you create different models/theories to support your math.
Hey, where did the Singularity come from? Is there an equation or theory where something appeared out nothing? Or is the muliti-Universe the prevailing thought now? I hear String Theory is dead.
Disclaimer, I'm agnostic, but I do watch The Big Bang Theory on TV and have stayed at a Hilton. Convince me I exist.
Conceptually, it is NOW very easy to understand.
FIND a massive cloud of Hydrogen floating in the universe. Give it enough time and as gravity draws the gas together, eventually it will get so big that it will start to get hot due to the massive pull of gravity from a massive amount of hydrogen.
If it gets enough gas to collapse enough to get hot enough, the hydrogen will have enough energy to FUSE (or FUSSION) where the hydrogen atoms combine to form helium.
Helium weighs SLIGHTLY less than the hydrogen that formed it and that is where Einstein's famous equation comes into play:
ENERGY = MASS x C**2 where C is the speed of light squared. The mass change is small BUT the speed of light is a large number hence with Zillions of hydrogen atoms per second combining that means lots of energy. The energy emitted helps to keep the interior of this hydrogen ball hotter.
Eventually the hydrogen is used up and then the helium fuses which makes even heavier atoms. But that process eventually stops when the hydrogen is used up and the heavier atoms cant' fuse anymore (the heavier ones don't fuse as well) and a huge explosion occurs. Depending on the mass of this ball of gas, big ones make the biggest booms, smaller ones like our sun boom and collapse.
Search on YOUTUBE for DAVID BUTLER and watch a few of his videos.
A navy vet? I started my nuclear education in Navy Nuclear Power School, Mare Island, Cal.
Nice pic.
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