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Everything posted by Genady
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Mu nought and Epsilon Zero values used by Maxwell
Genady replied to Logicandreason's topic in Classical Physics
Units need to be compatible. They don't need to be the same. Compatible does not mean equal. -
The instinct of reality is distorted by current physics
Genady replied to wei guo's topic in Speculations
How do you know that this mathematical equation does not represent physical properties? -
Mu nought and Epsilon Zero values used by Maxwell
Genady replied to Logicandreason's topic in Classical Physics
Ever heard of F=ma? m is in kg, a is in m/s2. Different units multiply just fine. -
It looks as I misused the term "flow regime". Let's see what we agree on. When a fluid freely flows in a tube, its pressure on the tube walls in areas with a larger cross-section is higher and its velocity there is slower than its pressure and velocity in areas with a smaller cross-section. However, the statement, "when there is movement of a fluid within a solid body there is less pressure on every point of the surface of the solid body from the fluid" is incorrect. Less than what? Where is a tube with different cross-sections?
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Any ideas on how to do this?
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What makes you think that Turing Machine cannot be applied to real world, cannot learn from data, adapt and improve?
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Yes, they are so stupid now that it is not difficult to make them smarter.
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This is correct. This does not follow from the preceding paragraph. In the preceding paragraph, the pressure in two points of the same flow is compared. In the latter, two different flow regimes are compared.
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AFAIK, the fine structure constant is one of about two dozen numbers that need to be measured experimentally and plugged in the SM by hand because there is no known way to derive them from first principles. When the founders of QM called it "the most fundamental unsolved problem in physics," about 100 years ago, there were not that many of such numbers and many other unsolved problems, e.g., quantum gravity, dark energy, etc., were not yet known or formulated. I don't think it is generally considered as such today.
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The instinct of reality is distorted by current physics
Genady replied to wei guo's topic in Speculations
Why compare everyday language with math. What we discuss in above is to compare math with logic. OK, compare with logic. What does it mean in logic? -
Mu nought and Epsilon Zero values used by Maxwell
Genady replied to Logicandreason's topic in Classical Physics
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The instinct of reality is distorted by current physics
Genady replied to wei guo's topic in Speculations
Here is a mathematical statement: It has a profound meaning in math. What does it mean in English or Chinese? -
Singularity is a consequence of GR. Gravitational wave is a consequence of GR. In GR, singularity is NOT a gravitational wave. If you want to consider a singularity as a gravitational wave, then either the singularity or the gravitational wave (or both) should be NOT what they are in GR, but something else. What are they?
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It's not even why they think what they think. We don't know what they think. We only might discuss why they said what they said.
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OK, this looks like the Fourier series I've mentioned. Any wave can be decomposed into a sum of weighted sinusoidal waves. Each component wave behaves independently, and the resulting wave behaves as their sum. The component waves do not affect each other.
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No, you didn't upset me. By vague I mean that answers depend on what you refer to as wave and as wave carrying wave.
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It doesn't make sense to go on with this vague language. The only way to ask and to answer meaningfully is to use mathematics. Check, e.g., Fourier series.
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Please, don't eliminate infinities. I like them. A lot. I'd argue to the contrary. So, it can exist then. But not by us.
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I'd like to know what you've posted, but I can't, because a) I'd have to follow the link, which is against the rules, and b) the link is a URL shortener, which is not advised to follow.
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Mu nought and Epsilon Zero values used by Maxwell
Genady replied to Logicandreason's topic in Classical Physics
Step-by-step derivation here: How to Derive the Speed of Light from Maxwell's Equations: 7 Steps (wikihow.com) -
How common are river creature myths in folklores of different cultures?
Genady replied to Alfred001's topic in Other Sciences
Here are some lists: Category:Piscine and amphibian humanoids - Wikipedia or more generic Category:Mythological aquatic creatures - Wikipedia -
About the wing: the point is to create a difference in pressure above and below. The pressure does not need to decrease on both sides. It can stay the same below the wing and decrease above the wing. So, it does not contradict that moving fluid does not necessarily have a decreased pressure. However, I think that your common sense understanding of Bernoulli's principle is incorrect. There are many solid explanations of it online. There are also various mathematical forms of the Bernoulli equation. E.g., If a pump makes a work, -ws, then the velocity, V, can change without a change in the pressure, P.
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Yes. Why not?
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No, I don't see why causing the fluid to move would decrease the pressure within the fluid. The Bernoulli's principle doesn't say so, AFAIK. I think you're right and I see where some decrease in pressure above the sinking piston might come from. As the piston moves down and the fluid above it moves down with it, a level of the top surface of the fluid is lowered because it takes time for the fluid sipping in from below to fill the gap. Thus, the height of the fluid column above the moving piston is smaller than "normal", and the pressure is lower accordingly.