hmmm.... ok, I understand the difference. I guess zero gravity is not experienced anywhere in the universe then. I can't come up with any location in the entire universe where there is pure "zero gravity."
There is a big difference between free-falling in the atmosphere and free-falling in an airplane: the air does not rush past you in the airplane and that is why it is called "zero gravity". When you free-fall out of an airplane, (or a balloon), after about 12 seconds you reach terminal velocity. The air friction against your fall negates the acceleration that the earth exerts on you. Free-falling in an airplane does not cause this as the air in the plane moves with you. Hence, for all "practical" purposes, you are experiencing zero-g. I know. I have experienced several 5 seconds zero-g flight simulation. Good pilots can emulate the particular flight trajectories needed.
It is not nonsense. (And for the record, this is not insightful but "full of it".) Science is obtuse to 99.9% of the population. To get funding, scientists need to explain to the common folks what their work is in terms they can understand, or, in this case, hear. So what if people have the impression they understand more than what they really do? Isn't this good for science?
If science remains obtuse to common folks, what is gained? Are scientists really that full of themselves that they want to sneer on people who think they have an understanding? Now, that is nonsense.
I don't think we ought to use "it can hold an atmosphere" as a marker for a planet. Planetoids like Pluto and now Sedna are so cold (being so far from the Sun) that their surface will be frozen. Atmosphere escapes due to two facts: 1) gravity of body is too weak and 2) surface temperature enables the atmosphere to evaporate because its mean temperature allows the gas to go faster than the escape velocity. So a small planetoid far enough can still have an atmosphere because it is too cold to escape.
Mathematics is an invented human language
on
The Golden Ratio
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· Score: 2, Insightful
It may be shocking to some, but mathematics is an invented language. It is used to describe physical events around us. But invented it is. When we state that 1 + 1 = 2, we already make assumptions (such as the + and = operators are neutral) and we know that in the mathematics of quantum mechanics 1 + 1 is not two because "adding" injects its own effect and that "equal" depends on the situation (is it a wave or a particle - it depends on the experiment.)
So is mathematics an invented language, yes. Is it a language that waited to be discovered, well, that is the question.
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hmmm.... ok, I understand the difference. I guess zero gravity is not experienced anywhere in the universe then. I can't come up with any location in the entire universe where there is pure "zero gravity."
There is a big difference between free-falling in the atmosphere and free-falling in an airplane: the air does not rush past you in the airplane and that is why it is called "zero gravity".
When you free-fall out of an airplane, (or a balloon), after about 12 seconds you reach terminal velocity. The air friction against your fall negates the acceleration that the earth exerts on you.
Free-falling in an airplane does not cause this as the air in the plane moves with you. Hence, for all "practical" purposes, you are experiencing zero-g.
I know. I have experienced several 5 seconds zero-g flight simulation. Good pilots can emulate the particular flight trajectories needed.
It is not nonsense. (And for the record, this is not insightful but "full of it".) Science is obtuse to 99.9% of the population. To get funding, scientists need to explain to the common folks what their work is in terms they can understand, or, in this case, hear. So what if people have the impression they understand more than what they really do? Isn't this good for science? If science remains obtuse to common folks, what is gained? Are scientists really that full of themselves that they want to sneer on people who think they have an understanding? Now, that is nonsense.
I don't think we ought to use "it can hold an atmosphere" as a marker for a planet. Planetoids like Pluto and now Sedna are so cold (being so far from the Sun) that their surface will be frozen. Atmosphere escapes due to two facts: 1) gravity of body is too weak and 2) surface temperature enables the atmosphere to evaporate because its mean temperature allows the gas to go faster than the escape velocity. So a small planetoid far enough can still have an atmosphere because it is too cold to escape.
It may be shocking to some, but mathematics is an invented language. It is used to describe physical events around us. But invented it is. When we state that 1 + 1 = 2, we already make assumptions (such as the + and = operators are neutral) and we know that in the mathematics of quantum mechanics 1 + 1 is not two because "adding" injects its own effect and that "equal" depends on the situation (is it a wave or a particle - it depends on the experiment.) So is mathematics an invented language, yes. Is it a language that waited to be discovered, well, that is the question.