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Pjpic
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Is there a reason that c has that particular value?
DaleSpam said:Is there a reason that it should have some other value?
It seems to be a fundamental built in property of our universe.Pjpic said:Is there a reason that c has that particular value?
mgb_phys said:It seems to be a fundamental built in property of our universe.
That makes sense -thanks
Or in other words, "The reason c has the value it does is http://www.bipm.org/en/si/si_brochure/chapter2/2-1/metre.html" "nuby said:Because it was created to have that value, with 1 meter.
DaleSpam said:Or in other words, "The reason c has the value it does is http://www.bipm.org/en/si/si_brochure/chapter2/2-1/metre.html" "
mgb_phys said:It seems to be a fundamental built in property of our universe.
The value comes out of maxwell's equations from the permeability and permativity of free space - although in practice it's easier to measure the speed of light and calcualte the permeability and permativity from that.
In practical terms the experimental value of the speed of light is so well known that it is fixed and the length of the meter changes as new measurements are made.
In this question it is not c but the meter and the second that are arbitrary. In fact they have always been recognised as very arbitrary. You can have physical things that are less arbitrary however. A resonant frequency of the Cs atom for instance for time. (Then that is multiplied by a number that gives a time near that of the old second). As for m , well meters are defined by how far light travels in a second! (multiplied by a number to give something like the old meter).jeberd said:I think the question is why is it that the universe chose 3E8 m/s seemingly arbitrarily as the speed limit of the universe as apposed to so 4E8 or something even larger (or presumably smaller). So what makes that speed more special than another?
I don't think that there can be an answer to that question. It is just an axiom of nature.
he speed of light is not infinite. It does in fact have a finite speed. That being said, it can only have one finite speed. Why choose the speed that it did?
The speed of light, c, is considered a universal constant because it is the speed at which all electromagnetic radiation travels in a vacuum. This means that no matter where you are in the universe, light will always travel at the same speed. It is also a fundamental constant in Einstein's theory of relativity, which has been extensively tested and proven to be accurate.
The value of c was first determined by the Danish astronomer Ole Rømer in the 17th century using observations of Jupiter's moons. Later, it was more accurately measured by the French physicist Armand Fizeau in the 19th century using a rotating toothed wheel and a beam of light. Today, the most precise measurement of c comes from experiments using lasers and atomic clocks.
The value of c is approximately equal to 3 x 10^8 meters per second because it is defined by the International System of Units (SI) as the exact speed at which light travels in a vacuum. This value was chosen to make calculations and measurements easier, as it is a round number and can be easily converted to other units of measurement.
Yes, the value of c does vary in different mediums. It is a constant in a vacuum, but it decreases when light travels through a medium such as air, water, or glass. This is due to the interaction between the light and the molecules in the medium, which causes the light to slow down.
According to our current understanding of physics, the value of c is a fundamental constant and cannot change. It is a key component in many fundamental equations and theories, such as Einstein's theory of relativity and the famous equation E=mc^2. However, some theories, such as string theory, suggest that c may have varied in the early universe. This is still a topic of ongoing research and debate.