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If I was born on Pluto* and my clock was a Caesium clock, and for thought the clock ran at half the rate of an Earth clock, would I measure the speed of light in a vacuum to be 599585136 m/s?
added- because if we agree on the length of 1 second of light
added - 9 192 631 770 periods of the radiation at ground state relative to what exactly?
No. You would do enough experiments to convince yourself that the speed of light is constant so you would define the second and the meter in terms of the speed of light and the frequenxcy of your clock.
the phrase is meaningless, so we wouldn't agree on it.
relative to one period. It's a number, obtained by counting. *this may explain a lot!
A number obtained by counting, relative to one period, please explain what one period suppose to mean?
I have a feeling one period = one period because surely science is not daft enough to measure a shorter period and declare there is a change.
I (on Pluto) tell you (on Earth) according to my clock it only took half a second because my time runs slower than your time
on Pluto ...the clock ran at half the rate of an Earth clock
we have to agree on the length of a second
if I was on Pluto I would disagree on the length of a second
measure the speed of light in a vacuum
you are on Earth measuring the speed of light in a vacuum, I am on Pluto observing you doing the experiment
would I measure the speed of light in a vacuum to be 599585136 m/s?
either both of our clocks were wrong, or the speed of light is wrong, so which is it?
The fact that your clock on Pluto looks different to a clock on Earth, and the length of a meter on Pluto looks different from a meter on Earth is purely due to the fact that you are in different frames of reference.
If you transported the equipment from Earth to your lab on Pluto, you would now find yourself in violent agreement about the duration of a second, the length of a meter and the speed of light in a vacuum.
Different frames of reference, I disagree, both our frames of reference is our Sun.
Exactly that, I was born on Pluto , I have transported myself and my equipment to your lab, I am disagreeing with you about the speed of light, a meter and time.
Quote from: TheBoxDifferent frames of reference, I disagree, both our frames of reference is our Sun.You may measure the distance from Pluto to the Sun, and from Earth to the Sun.But when you do an experiment on Pluto or on the Earth, you are not doing an experiment in the frame of reference (FoR) of the Sun.When you do an experiment on the surface of the Sun, you are about 0.7 million km out of the Sun's gravitational well, traveling around the Sun at about 2 km/s (at the equator).When you do an experiment on Earth, you are about 150 million km out of the Sun's gravitational well, traveling around the Sun at about 30 km/s.When you do an experiment on Pluto, you are about 6,000 million km out of the Sun's gravitational well, traveling around the Sun at about 5 km/s. These different positions in the Sun's gravitational well, and their different velocities, means that these three locations are in three different FoR, and you expect that viewing results in a different FoR will produce different answers.By the way, there is a way that an observer on Earth & Pluto can observe an experiment done in the Sun's FoR: The Sun's atmosphere absorbs certain wavelengths of light, creating Fraunhofer lines. These spectral lines can be observed by telescopes on both Earth and Pluto. Both Earth and Pluto will consider the wavelength of the Sun's light to be slightly red-shifted compared to measurements in their own lab. A lab on Pluto will consider it more red-shifted than a lab on Earth. QuoteExactly that, I was born on Pluto , I have transported myself and my equipment to your lab, I am disagreeing with you about the speed of light, a meter and time. If you transported your lab equipment to Earth, you would agree with a measurement made on Earth of these fundamental quantities, which are believed to be invariant when measured in all FoR.Quoteyou are on Earth measuring the speed of light in a vacuum, I am on Pluto observing you doing the experimentThis is where a possible disagreement could occur - a naive observer sees a measurement which is done in a different FoR, and is puzzled by the apparent difference in results.
If you have a "second" that isn't the same as the second then you will get a different number for the speed of light.But the actual speed of light is the same.