I did not go to a Catholic school but heard the rumors about the Nuns and yardstick.
How long is a meter
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Why do we drive on a parkway and park on a driveway?
They got it wrong, but it had been that way for twenty years, so they said well let's stick with it now, and they did. This also effects the size of a liter of water and by extension the gram!
Thank you for the laugh, Jeff. The nuns that lorded over me in catechism were pretty mean indeed. I remember them using foot long rulers. The nuns cured me of Catholicism.
I no longer follow organized religion, but Sister Margaret Ann, in 4th grade, made a mark in my life. She advised me, and taught me to learn just for the sake of learning. Sister changed my life.
I like that you are grateful for the sister giving you guidance. I just think I was a bad kid who didn’t appreciate their efforts to make me repent. Fortunately, I never experienced the meter stick..
Human hair grows at a few nanometers per second. That one meter long beard took a while.
MolaKule
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That's the measured two-way speed of light, sometimes called the "canonical" speed of light, c.
What's the one-way speed of light from a source to an observer, such as from a star to an observer on the space station?
Reading about the speed of light made me remember the moment I registered the amount of time it takes for sunlight leaving the surface of the sun to reach earth: 8 minutes 20 seconds. I knew about the speed of light, but it was always applied to distant stars, not our own. So when I read that the sun that we see in the sky is already 8:20 in the past, it was a WOAH! Cool! moment for me.
c. It cannot be anything else, ever.
That’s how high up the apple that fell on Newton’s head was.
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Technically, wrong. That's an A2. 39.63 in (1,007 mm) (M16A2)
A meter is actually 39.3701" long.
burbguy82
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burbguy82
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This aspect is unproven. Nor is the latter that the speed is constant. Einstein himself said that the math works both ways and it was a consession. As I understand it, that is why the "theory" is just a theory and not a law. In absolute truth, there is no way to measure it to absolute accuracy, as what we observe is the light's reflection off of an object. If light can travel around an object, or be bent by gravity, and arrive at its destination at the same time as light that is not being effected, the speed cannot be constant or it must be instantaneous. The theory of Simultaneity kind of points in this direction.
c is variable, that like saying a 5lbs weigh is always five pounds
They had "The Board of Education" when I was in Catholic grade school (a cutting board), it replaced the paddle ball paddle when it got broken on someone... By HS we got bigger, they used an OAR! By the time I graduated in '82 it was retired.
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What’s even more wild is the quantum interactions between the emitter (sun) and receiver (human) do not seem to be dependent on time - meaning light “goes back in time” and alters its state after observation.
Physicists provide support for retrocausal quantum theory, in which the future influences the past
(Phys.org)—Although there are many counterintuitive ideas in quantum theory, the idea that influences can travel backwards in time (from the future to the past) is generally not one of them. However, recently some physicists have been looking into this idea, called "retrocausality," because it...
This stuff is crazy.
MolaKule
Staff member
That's the measured two-way speed of light, sometimes called the "canonical" speed of light, c.
"The one-way speed of light or Conventionality of Simultaneity Thesis - which we shall call CST, originally conceived by Hans Reichenbach[14] and verified by others. [5, 6, 8-9, 11, 12] The proposition that nature does not prefer one convention of simultaneity over another.:
We will use a spherically symmetric system with spherical coordinates. In the CST the speed of light as a function of direction relative to the observer is θ where θ is given by, cθ = c/(1-cosθ) where c is the canonical value of the speed of light. When θ = 0 this indicates the direction directly toward the observer. I.e., When θ = 0 this indicates the speed of light is infinite in the direction of the observer. The reason we’re using spherical coordinates is that when using the CST all events everywhere in the universe are observed in real time..."
From, "Relativity, Light Travel, and Space
Major Topics in Physics HandoutBy Me
References: Jammer, Max, Concepts of Simultaneity: from Antiquity to Einstein, and Beyond, The Johns Hopkins University Press, 2006; Salmon, W.C., The Philosophical significance of the one-way speed of light, Nous, pp. 253-292, 1977; Sarkar, S., and Statchel, J., Did Malament prove the non-conventionality of simultaneity in the Special Theory of Realtivity?, Philosophy of Science, 1999; Winnie, J.A., Special Relativity without one-way velocity assumptions Part I, Philosophy of Science, Vol. 37, 1970a; Winnie, J.A., Special Relativity without one-way velocity assumptions Part II, Philosophy of Science, Vol. 37, 1970b; Einstein, A., Lorentz, H.A., Minkowski, H., and Weyl, H, The Principle of Relativity: A Collection of Original Papers on the Special and General Theory of Relativity, Dover: New York, 1924; Edwards, W. F., Special Relativity in Anisotropic Space, American Journal of Physics; 31 (7): pp. 482–489, 1963; Giannoni, C., Relativistic Mechanics and Electrodynamics without One-Way Velocity Assumptions, Philosophy of Science, Vol. 45, 1978; Eddington, A., Space, Time, and Gravitation, Cambridge University Press, 1920. (This enlightening paper can also be retrieved from:
http://strangebeautiful.com/other-texts/eddington-space-time-grav.pdf ) ;
Reichenbach, H., The Philosophy of Space and Time, Dover: New York, 1958.
PM me if you would like more information on this very interesting topic. Hans Reichenbach was a student of Einstein.
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