How do you define "a model"?

[Robittybob1]

This is pretty much how all of science works.

 

#1 We don't have a universal equation of everything at this moment. That means, we have a lot of different equations for different situations. Each one of those equations have assumptions implicit in their derivation and domains of validity where they are known accurate and considered applicable. So, any time anyone uses an equation in science, the very first question is: is this equation valid for this situation? Or is it appropriate to use this model here?

 

#2 The above question is important because if you start misusing equations or models when they aren't applicable, it is like building a house on sand. Without a solid foundation, the house will collapse. In the same way, if you use an equation incorrectly early in a development, all conclusions based on that are suspect and probably not sound, either. It doesn't matter how logical or aesthetically pleasing a result is, if it is based on a poor assumption, it is rejected.

 

So, in the end, yes. In science every step is indeed disputed. It is the framework that has led to all the successes we enjoy from science today.

So it becomes pointless discussing new hypotheses here as every model proposed can be dismissed by just saying it wasn't scaled up enough or the equations might not be applicable. I feel to be fair the objections should be subjected to the same standard.

No objection unless you can show the objection is relevant.

[StringJunky]

...So it becomes pointless discussing new hypotheses here as every model proposed can be dismissed by just saying it wasn't scaled up enough or the equations might not be applicable. I feel to be fair the objections should be subjected to the same standard.

No objection unless you can show the objection is relevant.

You will only learn how to do it by having your ideas scrutinised. Instead of being negative about it, treat every direct hit against your idea as a lesson that you've learnt something from. I think, realistically, until you've been specialising in a science subject for at least 20 years you've got Bob Hope of presenting anything new in this century.

[Greg H.]

So it becomes pointless discussing new hypotheses here as every model proposed can be dismissed by just saying it wasn't scaled up enough or the equations might not be applicable. I feel to be fair the objections should be subjected to the same standard.

No objection unless you can show the objection is relevant.

Actually, the same rule does apply to the objections. Objections are scrutinized and if they are found not to apply, they can be safely ignored.

 

But as the proponent of the idea, it's largely your job to answer the objection or show why it doesn't apply. And that requires you to have some knowledge of the basics of those equations and it also requires you to be willing to revisit your idea in light of those objections, and possibly even admit you might be wrong.

 

Blindly following an idea in the absence of a reason to support it is called faith, not science.

Edited March 12, 2015 by Greg H.

[Robittybob1]

You will only learn how to do it by having your ideas scrutinised. Instead of being negative about it, treat every direct hit against your idea as a lesson that you've learnt something from. I think, realistically, until you've been specialising in a science subject for at least 20 years you've got Bob Hope of presenting anything new in this century.

Cheers! I thought I was onto something but without support and funding maybe it will just fade away.

[Bignose]

So it becomes pointless discussing new hypotheses here as every model proposed can be dismissed by just saying it wasn't scaled up enough or the equations might not be applicable. I feel to be fair the objections should be subjected to the same standard.

No objection unless you can show the objection is relevant.

That's not how a scientific dialog works.

 

If you think that an objection is irrelevant, the onus is on you to demonstrate how it isn't. This happens in science every day. Every single conference I have even been to, after a presenter has spoken, there are numerous questions. Did the presenter consider X? What are the limits on Y? Does you model cover phenomena Z? and so on.

 

These people aren't trying to be mean about it. Science is very confrontational in that, as above, everything ends up being questioned. If you know your topic, you should be able to answer these objections. Either by refuting them or conceding them. What doesn't work is to continue building a 2nd story onto your house built on sand, also known as, waving away objections.

 

You have to remember that you're going to get a lot of what you might consider "stupid" questions. People are going to question even some very basic things, sometimes. People are all different. Different levels of knowledge, understanding, etc. Especially on an internet forum like this.

 

The best way to deal with them is to explain why you think the objection is incorrect, cite a few sources that support your point of view, and do your best to explain yourself. Again, if you know the subject well, this should not be very difficult.

 

Cheers! I thought I was onto something but without support and funding maybe it will just fade away.

You keep citing the lack of support and funding, but not the lack of strong science behind it. Again, if you can build a good model, and show how that model makes predictions that agree well with what is observed, the funding and support will come. This is how funding works today. You show people that your work is worth funding by demonstrating how successful your model is, where success in science is largely about making predictions that agree closely with measurement.

Edited March 12, 2015 by Bignose

[Robittybob1]

Actually, the same rule does apply to the objections. Objections are scrutinized and if they are found not to apply, they can be safely ignored.

 

But as the proponent of the idea, it's largely your job to answer the objection or show why it doesn't apply. And that requires you to have some knowledge of the basics of those equations and it also requires you to be willing to revisit your idea in light of those objections, and possibly even admit you might be wrong.

 

Blindly following an idea in the absence of a reason to support it is called faith, not science.

I have always done that. I'm not saying "I'm right, stuff everyone else", but when objections come in that appear to be bordering on flaming it is frustrating. Agreement and acknowledgement of what the parties both agree on is also important.

Cheers any way, other things have to be done today.

Edited March 13, 2015 by Robittybob1

[StringJunky]

Cheers! I thought I was onto something but without support and funding maybe it will just fade away.

I hope you realise that was a general statement I made really, but it's true. I personally wouldn't even contemplate thinking I could bring something new to the table without having at least a Master's and fluent enough in the relevant maths to express my findings.

Edited March 12, 2015 by StringJunky

[Robittybob1]

I hope you realise that was a general statement I made really, but it's true. I personally wouldn't even contemplate thinking I could bring something new to the table without having at least a Master's and fluent enough in the relevant maths to express my findings.

The maths would help in the end but I have found the insights are simpler than that. The apple falling from the tree (Newton), the elevator free falling (Einstein), the electron orbiting the atom (Bohr). OK they were the initial concepts but they progressed from there. I must have had at least 5 revolutionary insights since coming onto the forums in the last 5 years or so. None have been accepted as yet but they are out there. Whether a super knowledge of math would make it easier to make people convinced? Yes, I think it would and that is why I have been brushing up on maths lately.

Will I ever get good enough to apply math? I doubt it.

Edited March 13, 2015 by Robittybob1

[StringJunky]

... Whether a super knowledge of math would make it easier to make people convinced? Yes, I think it would and that is why I have been brushing up on maths lately.

Will I ever get good enough to apply math? I doubt it.

Good for you! It will, at the very least, make you a better judge of your own work. I've just bought a few maths and physics books to enable me to go into theories more deeply and understand better how they were derived. There's only so far you can understand science without maths.

[Robittybob1]

Good for you! It will, at the very least, make you a better judge of your own work. I've just bought a few maths and physics books to enable me to go into theories more deeply and understand better how they were derived. There's only so far you can understand science without maths.

Will you get to use the maths? I find I don't get to use the maths enough so I forget it as fast as I learn it. What's your technique for making it sink in? I seem to be able to remember physics perfectly. So a model that is a type of "working model" is so much easier to conceive rather than a model based on a mathematical description.

[StringJunky]

Will you get to use the maths? I find I don't get to use the maths enough so I forget it as fast as I learn it. What's your technique for making it sink in? I seem to be able to remember physics perfectly. So a model that is a type of "working model" is so much easier to conceive rather than a model based on a mathematical description.

I intend to make maths a little hobby for the next few years so it will be regularly in my mind. The way to get things to stick is to use as many senses simultaneously whilst you are learning something; speak to yourself as you write, type or read. Apply the principle you have just learnt to a few scenarios. I find that if you don't understand something properly and its applications you won't remember it.

 

When I was stuck with algebra, many years ago, my grandad taught me that algebra is a language, that you read just like English, only it's in symbolic form. It's a language, not a problem. It made a big difference to how I perceived maths.

 

A model in visual or verbal form is only easier because you aren't used to doing it mathematically. Look at your learning as an ongoing journey rather than a final destination; you'll know more tomorrow than you do today.

[Bignose]

The maths would help in the end but I have found the insights are simpler than that. The apple falling from the tree (Newton), the elevator free falling (Einstein), the electron orbiting the atom (Bohr). OK they were the initial concepts but they progressed from there.

... and it is the 'progressed from there' part that is lacking. Regardless of whether you have the skills to do it yourself or not, the point is that to be scientifically useful, there needs to be more than just the story. The story of Newton's apple, Einstein's elevator, and Bohr's orbits are good visualizations of what is happening. It has some qualitative descriptions. However, there are sorely lacking in quantitative descriptions.

 

As in, sure it is useful to know that "the apple falls down". But, what is really scientifically useful to know is "how long until it hits the ground? what speed is it moving at? what if I get something twice the size?" etc. These are the steps that Newton did. He built a model (yes, a math equation) that could then be turned into predictions. "If I drop this apple from a height of 10 m, it will hit the ground in 2.6 seconds." Then you compare this prediction to an experiment where you measure the value you predicted, and compare. Math is useful here, too, because if you have two competing ideas, the one that makes closer predictions is considered more useful because its accuracy is greater than the other. If the prediction is good, huzzah! If the prediction is bad, then you need to go back and revise.

 

This is science as it is actually practiced and demonstrably successful today.

 

I am not saying that the initial "insight" isn't valuable. Because it is. The problem is in thinking that the insight alone is powerful in a scientific sense, and it really isn't. What is scientifically powerful is using that insight to create predictions that can be quantitatively compared to measurements. "Insight" alone is basically story telling. Again, story telling has its place, but scientifically it is pretty limited.

[StringJunky]

... I am not saying that the initial "insight" isn't valuable. Because it is. The problem is in thinking that the insight alone is powerful in a scientific sense, and it really isn't. What is scientifically powerful is using that insight to create predictions that can be quantitatively compared to measurements. "Insight" alone is basically story telling. Again, story telling has its place, but scientifically it is pretty limited.

Insight and maths are the complement of each other; neither is as useful alone as together

[Robittybob1]

 

http://www-istp.gsfc.nasa.gov/stargaze/Sgravity.htm

 

He then used his formula to derive Kepler's laws and thereby confirmed the model.

It wasn't clear from that link why Newton had the idea of multiplying mass times mass. Is gravitation the only situation where mass is multiplied by mass?

OK the idea of making it an inverse square would be from the idea of light weakening with distance. So that to me suggests he must have thought gravity as a type of radiating force, like light, fading at greater distances.

 

I suppose if you then think it is the radiant component of mass that is being radiated the gravitation force would be the shared radiation between the two radiant masses. I think you might get a "mass times mass" if you calculated shared radiation from that.

It was 100 or so years later that the value of G was found accurately. (I suppose Newton had some estimate.)

 

It took more than a century before it was first achieved. Only in 1796 did Newton's countryman Henry Cavendish actually measure such weak gravitational attraction, by noting the slight twist of a dumbbell suspended by a long thread, when on of its weights was attracted by the gravity of heavy objects. His instrument ("torsion balance") is actually very similar to the one devised in France by by Charles Augustin Coulomb to measure the distance dependence of magnetic and electric forces. The gravitational force is much weaker, however, making its direct observation much more challenging. A century later (as already noted) the Hungarian physicist Roland Eötvös greatly improved the accuracy of such measurements.

In what situation was Newton actually able to prove his gravitational formula?

 

Newton showed that if gravity at a distance R was proportional to 1/R^2 (varied like the "inverse square of the distance"), then indeed the acceleration g measured at the Earth's surface would correctly predict the orbital period T of the Moon.

Did Newton know "the distance R to the Moon is then about 60 RE."? Who first accurately estimated the distance to the moon?

Edited March 13, 2015 by Robittybob1

[Strange]

It wasn't clear from that link why Newton had the idea of multiplying mass times mass.

 

I assume he started with the idea that the gravitational force is proportional to mass (a heavier object requires more force to lift) and then deduced that it was proportional to both masses.

 

Is gravitation the only situation where mass is multiplied by mass?

 

I have no idea.

 

OK the idea of making it an inverse square would be from the idea of light weakening with distance. So that to me he must have thought gravity as a type of radiating force like light fading at greater distances.

 

Maybe.

 

It was 100 or so years later that his formula was proven with the finding of the value of G.

 

He verified it himself by deriving Kepler's laws.

 

Who first accurately estimated the distance to the moon?

 

Probably Eratosthenes.

 

No, apparently it was Hipparchus

 

The first person to measure the distance to the Moon was the 2nd-century-BC astronomer and geographer Hipparchus, who exploited the lunar parallax using simple trigonometry, measuring the distance as 400,000 kilometers. He was approximately 26,000 km (16,000 mi) off the actual distance, an error of about 6.8%

http://en.wikipedia.org/wiki/Lunar_distance_%28astronomy%29

Edited March 13, 2015 by Strange

[swansont]

It was 100 or so years later that his formula was proven with the finding of the value of G.

In what situation was Newton actually able to prove his gravitational formula?

 

There are applications where you are taking ratios, so the value of G drops out. The inverse-square nature of the force gives rise to Kepler's laws and elliptical orbits.

[Robittybob1]

 

I assume he started with the idea that the gravitational force is proportional to mass (a heavier object requires more force to lift) and then deduced that it was proportional to both masses.

 

 

I have no idea.

 

 

Maybe.

 

 

He verified it himself by deriving Kepler's laws.

 

 

Probably Eratosthenes.

 

No, apparently it was Hipparchus

http://en.wikipedia.org/wiki/Lunar_distance_%28astronomy%29

Thanks - from a Google search gravity seems the only use of formulas where mass is multiplied by mass. Does anyone know of any other?

When you look at the the dates there was thousands of years between the Eratosthenes and Newton. Science has been a slow process. What was the rush the other day?

[imatfaal]

Thanks - from a Google search gravity seems the only use of formulas where mass is multiplied by mass. Does anyone know of any other?

When you look at the the dates there was thousands of years between the Eratosthenes and Newton. Science has been a slow process. What was the rush the other day?

 

[latex]\oint_{\partial V}^{ }\mathbf{g}\cdot d\mathbf{A} = -4\pi GM[/latex]

 

feel free to ignore - I misread the previous post. Whoops

[Bignose]

Thanks - from a Google search gravity seems the only use of formulas where mass is multiplied by mass. Does anyone know of any other?

They are somewhat common in chemistry, in things like reaction equilibrium calculations, dependent on the reaction stoichiometry. There are drag correlations for solids moving through fluids that have multiplicative relationships between the densities of the two materials.

 

I agree that isn't isn't super common to see units of mass^2, but I think that the pattern of the product of the two target items is common. See Coulomb's Law, for example, with charge instead of mass.

[Robittybob1]

They are somewhat common in chemistry, in things like reaction equilibrium calculations, dependent on the reaction stoichiometry. There are drag correlations for solids moving through fluids that have multiplicative relationships between the densities of the two materials.

 

I agree that isn't isn't super common to see units of mass^2, but I think that the pattern of the product of the two target items is common. See Coulomb's Law, for example, with charge instead of mass.

Yes when you divide a mass with an atomic weight it ends up with a number of moles, something like that, it been a while since I've done any chemistry.

Do they then multiply that with mass again? If you see a link share it please.

 

[latex]\oint_{\partial V}^{ }\mathbf{g}\cdot d\mathbf{A} = -4\pi GM[/latex]

 

feel free to ignore - I misread the previous post. Whoops

No problems - I went back to bed so the whole world was ignored.

[Bignose]

Yes when you divide a mass with an atomic weight it ends up with a number of moles, something like that, it been a while since I've done any chemistry.

Do they then multiply that with mass again? If you see a link share it please.

equilibrium constants for the reaction A + B <--> C + D look like [math]k = \frac{[A]^a^b}{[C]^c[D]^d}[/math] The value of the exponents depend on the order of the reaction itself. There is a lot of masses (in the concentrations) multiplied and divided there.

Edited March 14, 2015 by Bignose

[Robittybob1]

equilibrium constants for the reaction A + B <--> C + D look like [math]k = \frac{[A]^a^b}{[C]^c[D]^d}[/math] The value of the exponents depend on the order of the reaction itself. There is a lot of masses (in the concentrations) multiplied and divided there.

Those "equilibrium constants" come out to be dimensionless numbers so they aren't really mass time mass or kg^2.

[John Cuthber]

Those "equilibrium constants" come out to be dimensionless numbers so they aren't really mass time mass or kg^2.

Not always.

[Robittybob1]

Not always.

I was just going off a chemistry lecture on the topic on YT. I have a feeling even if they did have some sort of units that was not the purpose of the index. Do you use them?

[Bignose]

I was just going off a chemistry lecture on the topic on YT. I have a feeling even if they did have some sort of units that was not the purpose of the index. Do you use them?

They are in general not dimensionless. a + b doesn't have to equal c + d. Those all depend on the order of the reaction. And they are used to predict the results of chemical reactions. There is kind of a whole industry built around knowing these constants very accurately. It's called chemical engineering.