If God Existed, What Would He Be Like?

Debate Room
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I suppose another example would be estimating the mass of the earth. I do not know for example, a scale large enough to ‘directly’ obtain the earths mass.

" No, the mass of the Earth cannot be directly measured; it’s determined indirectly by using Newton’s Law of Universal Gravitation, the gravitational constant, and the Earth’s radius and gravitational acceleration.

Here’s a more detailed explanation:

  • Indirect Measurement:

The Earth is too large and massive to be placed on a scale, so scientists rely on indirect methods to determine its mass.

  • Newton’s Law of Universal Gravitation:

This law describes the gravitational force between two objects, which is directly proportional to their masses and inversely proportional to the square of the distance between them.

  • Gravitational Constant (G):

This constant, determined experimentally, is a fundamental value in the law of universal gravitation.

  • Earth’s Radius and Gravitational Acceleration:

By knowing the Earth’s radius and the acceleration due to gravity (g), scientists can calculate the Earth’s mass using the gravitational constant and Newton’s law.

  • Cavendish Experiment:

The first successful attempt to measure the mass of the Earth involved the Cavendish experiment, which determined the value of G.

  • Modern Methods:

Scientists use satellite data and precise measurements of the Earth’s gravity field to refine the calculation of its mass"

I suppose another example might be, if one carefully took track of an animals activity, and its amount of intake, one could estimate the animals metabolic rate. I actually assisted in a research project on this, where I sat and watch a animal for hours, noting how many times it nodded its head, or got up and walked etc. Very boring, and probably would have been better do to with video footage.

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You didn’t answer my question, instead you just sent me some trivial facts I already know.

My question is: What is the difference between a direct and indirect measurement? For example, lets say I wanted to measure the velocity of a toy model train on a toy track. I measure its position at time 1, and at time 2, then calculate the velocity. Is this a direct or indirect measurement of velocity?

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In the case of the earth’s mass, its not directly being measured. What is being measured is other things, like its gravity, density, volume estimate etc. How is this not answering your question?

In the case of the animal, its metabolism is not directly being measured, but its activity, amount of food being consumed, and the animals mass etc…something other than its metabolism is measured, so its not directly being measured.

The other factors being measured an put into a formula. One supplies the variables, and one gets an value of the unknown as the result

65

You still haven’t answer my question, but maybe you can answer this instead:
How do you make a direct measurement of the mass of rock?(a rock small enough to be moved easily)

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hum…question everything, consider nothing… A rock if its the right size and weight can be placed on a scale…I thought that was pretty obvious that would be a direct measurement. But I suppose your saying that is not?

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Right. Scales don’t measure mass. Try again.

68

I’ll cut to the punchline. There is no [known] way to make a direct measurement of mass, according to how you’ve defined direct measurements.

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Yes, gravity working on mass. So, mass doesn’t exist then, because its not directly measured?

it would seem the ‘weasel’ word is direct…not indirect. Whatever ‘weasel’ is supposed to mean in this context. I never considered a weasel to do science.

The better example is about animal metabolism. I think the problem was estimation of metabolism of particular animals in a relaxed state. One could very well put a vent on an animal and plug its nose, and measure the amount of co2, but that stresses the animal I am sure. So, at that point, the only information was on vented animals, or animals placed in very confined spaces.

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So, that is the original discussion about measuring dark matter. Its “indirect”. So I suppose as suspect as any measurement of mass?

I am sure there are other possibilities, its not being ‘indirectly’ measured correctly. The current science related on the topic is not as good as it needs to be to confirm or deny the existence of dark energy, or dark matter. It could be completely fabricated. Somehow I don’t think so, its probably an error of some kind in astronomic observations.

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I’d like you to tell me how to make a direct measurement. Lets say of velocity of a bowling ball?

I’m suggesting that by your definition, all measurements are indirect, in which case your criticism for a measurement being indirect is meaningless.

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No, the criticism was the ‘weasel’ word ‘indirect’. Whatever ‘weasel’ means. About the existence of dark matter, that was suggesting that dark matter doesn’t exist because its existence was inferred ‘indirectly’. I didn’t start that.

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Thankyou for the information

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Yes it exists, mass is a fundamental property of objects, and we can measure its effects, like inertia and gravitational attraction, which allows us to determine mass indirectly. The fact that mass isn’t directly measured doesn’t mean it doesn’t exist.

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Could you please tell me how to measure the velocity of a bowling ball (or any other object of your choice) without doing it “indirectly”?

eta: actually velocity is harder than speed, if you’d rather do speed that would be fine.

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In my opinion, as a physicist, this whole discussion about direct vs indirect measurements of <whatever> is semantic hair-splitting. The hard facts is that to measure <whatever>, we need one or more devices to aid with the measurements (information gathering). This can be mechanical, electric, or electronic devices, or just our built-in senses. Thus, we are already one step away from the object or the property by using these devices to help interpret what we observe. Next, we need some physics theory plus some results from experimental physics to make inferences, either by direct calibration of the measurement devices, and/or through analysis of the data, and/or through deduction. So, whether you call the measurement of <whatever> direct or indirect, is in my opinion immaterial. You will need, at some stage, some sort of inference based on our current knowledge about the physical world. Whether that is when you build the devices that help with the measurements or in the data analysis, or both, is unimportant.

To make things less linguistically complicated, one can decide to call e.g. measuring distances or sizes with tape measures, calipers, or laser ranges direct, and one can call measurements where you have a greater degree of freedom to use deduction and interpretation as indirect. But that all depends on context, who says it, and who will be using the results.

TLDR; Making clear distinctions between direct and indirect measurements is IMHO semantic hair-splitting. Whether you call it one or the other depends on context and how you want to define the two.

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Yep, that is why I said it is a weasel word. Used to discredit things the speaker doesn’t like (by arbitrarily labeling them as indirect).

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78

I will probably start using words like " je’unai" to be more explicitly sarcastic.

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Of course, the usual suspects won’t bother learning about the subtleties involved, but instead will think along the lines of “Yay! More apologetic fodder!”

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