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Happens to many people who get involved in popular science. They're slowly but surely attracted to the whirlpool of fringe scientific ideas. 'Do we live in a simulation?' is one of them, IMO. How about, for example, one is a constant (it has to be) and the other clusters (it must). So they are very very different. In the quantum theory, one must correspond to the ground state of all the oscillators. The other must correspond to real states (non-virtual). Excited states of quantum field theory of something we don't know.2 points
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The question is one of scale, not balance. If you use GR to model any gravitational mechanics on a scale of the solar system, or some few multiples of it, you get the correct results to very high levels of accuracy - so the equation isn’t “flawed” in any meaningful sense. Remember that we have tested it very extensively locally here in the solar system. Rather, what happens is that on large scales, systems behave as if they contain much more matter than is visible in the electromagnetic spectrum. Fundamentally, this can mean one of three things: 1. There’s extra stuff there which we can’t see (dark matter) 2. There’s nothing extra there, but the laws of gravity have to be modified on larger scales; GR remains perfectly valid on solar scales 3. There may be some kind of other interaction happening, over and above gravity, which we don’t know about. So whatever happens, GR will remain a valid and good model; at most, its domain of applicability might become more limited.2 points
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That’s just silly Source: me, who worked for ~25 years at the US Naval Observatory in the precise time department1 point
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Looking at far-away galaxies that were in the early universe at about 10 Billion years ago, we note similar galactic rotation curves, indicating that, except for a few anomalies, Dark Matter was similarly distributed and concentrated in the early universe. Since then, the expansion of the universe has undergone a continual acceleration, indicating that the Dark Energy forcing this expansion has undergone a change, IOW Dark Energy has changed in the 10 Billion year interval; Dark Matter has not. Makes it hard to imagine they could be co-dependent or related. NASA called. They said you should stop mis-interpreting their link.1 point
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That (rather confusingly laid out) article does not claim that dark matter and dark energy are "so intertwined they cannot be separated". It contains two separate sections, one on dark energy, then a brief one on dark matter, and finally something on the total energy and matter content of the cosmos.1 point
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Dark matter and dark energy are placeholder terms for the entirely separate phenomena of the observed anomalous galactic rotations rates and the observed accelerating expansion of the cosmos. There is no evidence they are connected and no theoretical reason I am aware of why they should be. What you have just written does nothing to address the dark matter phenomenon. Do you have evidence dark matter and dark energy are related in the way you say? But now that your agenda has at last surfaced (I was wondering when it would), perhaps it's time this discussion is moved to "Speculations".1 point
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Excerpt: "Note that while time is a fundamental concept in our understanding of the physical world, its nature is complex and interconnected with other aspects of physics, such as gravity, relativity, and quantum mechanics. The understanding of time has evolved with advancements in physics and continues to be an area of exploration and investigation." -- End of excerpt. -- ChatGPT 3.5 updated January 2022 ~~~~~~~~~~~~~~~~~~ And I'm just only trying to explore the concept of time especially with physics in mind. Sigh..-1 points
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I can write out unbalanced equations all day and night, as there is no special talent needed to write a flawed equation where 85% of the expected sum is not there. In architectural engineering school one who loses 85% of the sum fails, same in accounting. Only in physics is the wrong answer awarded a prize.-1 points
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Actually, NASA does not know, but has several theories, so you are actually asking me to explain and justify what NASA can't. So if I could do that I would be a Nobel Prize winner instead of an investor in Apple Computers https://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/ In the early 1990s, one thing was fairly certain about the expansion of the universe. It might have enough energy density to stop its expansion and recollapse, it might have so little energy density that it would never stop expanding, but gravity was certain to slow the expansion as time went on. Granted, the slowing had not been observed, but, theoretically, the universe had to slow. The universe is full of matter and the attractive force of gravity pulls all matter together. Then came 1998 and the Hubble Space Telescope (HST) observations of very distant supernovae that showed that, a long time ago, the universe was actually expanding more slowly than it is today. So the expansion of the universe has not been slowing due to gravity, as everyone thought, it has been accelerating. No one expected this, no one knew how to explain it. But something was causing it. Eventually theorists came up with three sorts of explanations. Maybe it was a result of a long-discarded version of Einstein's theory of gravity, one that contained what was called a "cosmological constant." Maybe there was some strange kind of energy-fluid that filled space. Maybe there is something wrong with Einstein's theory of gravity and a new theory could include some kind of field that creates this cosmic acceleration. Theorists still don't know what the correct explanation is, but they have given the solution a name. It is called dark energy. What Is Dark Energy? More is unknown than is known. We know how much dark energy there is because we know how it affects the universe's expansion. Other than that, it is a complete mystery. But it is an important mystery. It turns out that roughly 68% of the universe is dark energy. Dark matter makes up about 27%. The rest - everything on Earth, everything ever observed with all of our instruments, all normal matter - adds up to less than 5% of the universe. Come to think of it, maybe it shouldn't be called "normal" matter at all, since it is such a small fraction of the universe. Universe Dark Energy-1 Expanding Universe This diagram reveals changes in the rate of expansion since the universe's birth 15 billion years ago. The more shallow the curve, the faster the rate of expansion. The curve changes noticeably about 7.5 billion years ago, when objects in the universe began flying apart as a faster rate. Astronomers theorize that the faster expansion rate is due to a mysterious, dark force that is pulling galaxies apart. Credit: NASA/STSci/Ann Feild Universe Dark Energy-1 Expanding Universe This diagram reveals changes in the rate of expansion since the universe's birth 15 billion years ago. The more shallow the curve, the faster the rate of expansion. The curve changes noticeably about 7.5 billion years ago, when objects in the universe began flying apart as a faster rate. Astronomers theorize that the faster expansion rate is due to a mysterious, dark force that is pulling galaxies apart. Credit: NASA/STSci/Ann Feild One explanation for dark energy is that it is a property of space. Albert Einstein was the first person to realize that empty space is not nothing. Space has amazing properties, many of which are just beginning to be understood. The first property that Einstein discovered is that it is possible for more space to come into existence. Then one version of Einstein's gravity theory, the version that contains a cosmological constant, makes a second prediction: "empty space" can possess its own energy. Because this energy is a property of space itself, it would not be diluted as space expands. As more space comes into existence, more of this energy-of-space would appear. As a result, this form of energy would cause the universe to expand faster and faster. Unfortunately, no one understands why the cosmological constant should even be there, much less why it would have exactly the right value to cause the observed acceleration of the universe. Dark Matter Core Defies Explanation This image shows the distribution of dark matter, galaxies, and hot gas in the core of the merging galaxy cluster Abell 520. The result could present a challenge to basic theories of dark matter. Another explanation for how space acquires energy comes from the quantum theory of matter. In this theory, "empty space" is actually full of temporary ("virtual") particles that continually form and then disappear. But when physicists tried to calculate how much energy this would give empty space, the answer came out wrong - wrong by a lot. The number came out 10120 times too big. That's a 1 with 120 zeros after it. It's hard to get an answer that bad. So the mystery continues. Another explanation for dark energy is that it is a new kind of dynamical energy fluid or field, something that fills all of space but something whose effect on the expansion of the universe is the opposite of that of matter and normal energy. Some theorists have named this "quintessence," after the fifth element of the Greek philosophers. But, if quintessence is the answer, we still don't know what it is like, what it interacts with, or why it exists. So the mystery continues. A last possibility is that Einstein's theory of gravity is not correct. That would not only affect the expansion of the universe, but it would also affect the way that normal matter in galaxies and clusters of galaxies behaved. This fact would provide a way to decide if the solution to the dark energy problem is a new gravity theory or not: we could observe how galaxies come together in clusters. But if it does turn out that a new theory of gravity is needed, what kind of theory would it be? How could it correctly describe the motion of the bodies in the Solar System, as Einstein's theory is known to do, and still give us the different prediction for the universe that we need? There are candidate theories, but none are compelling. So the mystery continues. The thing that is needed to decide between dark energy possibilities - a property of space, a new dynamic fluid, or a new theory of gravity - is more data, better data. What Is Dark Matter? By fitting a theoretical model of the composition of the universe to the combined set of cosmological observations, scientists have come up with the composition that we described above, ~68% dark energy, ~27% dark matter, ~5% normal matter. What is dark matter? We are much more certain what dark matter is not than we are what it is. First, it is dark, meaning that it is not in the form of stars and planets that we see. Observations show that there is far too little visible matter in the universe to make up the 27% required by the observations. Second, it is not in the form of dark clouds of normal matter, matter made up of particles called baryons. We know this because we would be able to detect baryonic clouds by their absorption of radiation passing through them. Third, dark matter is not antimatter, because we do not see the unique gamma rays that are produced when antimatter annihilates with matter. Finally, we can rule out large galaxy-sized black holes on the basis of how many gravitational lenses we see. High concentrations of matter bend light passing near them from objects further away, but we do not see enough lensing events to suggest that such objects to make up the required 25% dark matter contribution. Abell 2744: Pandora's Cluster Revealed One of the most complicated and dramatic collisions between galaxy clusters ever seen is captured in this new composite image of Abell 2744. The blue shows a map of the total mass concentration (mostly dark matter). Abell 2744: Pandora's Cluster Revealed One of the most complicated and dramatic collisions between galaxy clusters ever seen is captured in this new composite image of Abell 2744. The blue shows a map of the total mass concentration (mostly dark matter). However, at this point, there are still a few dark matter possibilities that are viable. Baryonic matter could still make up the dark matter if it were all tied up in brown dwarfs or in small, dense chunks of heavy elements. These possibilities are known as massive compact halo objects, or "MACHOs". But the most common view is that dark matter is not baryonic at all, but that it is made up of other, more exotic particles like axions or WIMPS (Weakly Interacting Massive Particles Please elaborate as to how you know how they are not intertwined as neither has ever been observed? Do you know something that NASA does not? https://science.nasa.gov/astrophysics/focus-areas/what-is-dark-energy/-1 points
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Oh.., first, a dynamic electromagnetic field gets dynamic from several sources. Normally a AC current through conductors or radio antennas do. At the case with the AC current we get 60 or 50 Hz depending on country. The dynamic field's fluctuation therefore is dependent on the source's frequency.. hmm.. How this reveals the concept of "time".. yes.. We obviously have to get back to the clock describing. A clock is a fixed pace tech... So, we're back to the initial quest, "what is time? And time very distinct by everybody here was expressed with: Time is what a clock, preferably a atomic cesium 133 construction, presents. Time explanation seems going in circles. And time obviously does not easily reveal its true nature. For me it looks like time being an imaginary physical reference unit. Though a most used, and therefore a most important, such.-2 points
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Wikipedia, is where any third grader can post their science-2 points
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I did not write that, I copied it from www.space.com so you can take the issue up with them, if you choose https://www.space.com/dark-energy-what-is-it#:~:text=Think of dark energy as,them together as gravity does.-2 points
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There is no way to separate two things that have never been observed, so can you tell us how you know that they are not one in the same? LOL you are correct NASA level theory can be confusing for some-3 points