Butch

Sorry, folks... tired brain, will work more on question than solution.

I am only looking for a vector statement to show that the gravitational influence of the 2 point system on the single point reduces as the distance between the 2 constituents of the 2 point system increases... I understand the vector math, but lost on the proper formula syntax. I could draw it and deduce it, but a singular mathematical statement eludes me.

It would do to consider the 2 point system to be static except for them receding from one another tangent to the single point.

BTW Thank you Swan.

2 hours ago, mathematic said:

Use inverse squarer relationship.  Your description doesn't describe the motion of the first two relative to the third.

I am using that relationship, however showing that the 2 point system influence diminishes with the distance between the 2 is what is eluding me... I suppose I need to reference the point equidistant from the 2 and apply the 1/x^2 there. Sorry people, probably making this more complex than need be.

And thank you mathematic.

Perhaps I can restate...

The resultant of 2 vectors with a common origin decreases as theta increases. I need a simple proof.

That is not exactly correct.

Given 2 gravitational points in a close oscillatory relationship and a 3rd at a relativly greater distance, how would I demonstrate mathematically that the influence of the first 2 upon the 3rd decreases as the distance between the first 2 increases?

Assume the oscillatory relationship to be circular, or an average.

On 2/12/2020 at 6:15 AM, swansont said:

It's not an either/or situation. Drawing mental pictures based on the math and physical laws is kinda what scientists do.

By abstract I mean apart from the math or physical laws... Not in disagreement with them certainly. Abstract thought leads to math and physical laws that have not been revealed. As an example, Einstein had first to consider how light would appear (with existing theory) if he were traveling at c and thus he produced new physical laws and the math for them. Abstract thought is often the pathway to discovery.

5 hours ago, Phi for All said:

Wow, can you imagine if that were true?! All that meticulous methodology, all that gathered knowledge, for all those centuries, down the drain! Everything we trust reduced to individual "logical beliefs"! A true hell indeed, since nothing could be relied upon.

Oh, you must be joking. You scoundrel, you had me going there for a minute.

Not joking... Have you never seen accepted science overturned? We forge ahead with what we think we know and go into the unknown with expectations of what we will find... often we are quite suprised.

7 hours ago, swansont said:

The value of the elementary charge is not 1.602176634×10−19 C? (a defined SI unit)

 

As far as we know it is... Euclid was rock solid until Einstein came along and got him all out of shape. 

5 hours ago, Strange said:

I think the first part is spot on. Not so sure about the last sentence. Yes, the macroscopic concepts we are familiar with in everyday life emerge from the underlying quantum reality, in ways we don't fully understand.

But I think it would be going a bit too far to say we do not understand the quantum realm "at all". Arguably, we understand it as well as any other area that we have accurate models for. Perhaps it feels like we don't understand it as well because it is less intuitive than some of the other models we have.

You have a wonderfully abstract mind! Many do not have that attribute to work with, many can only see such things as math or physical laws... If your mind can draw pictures of these abstract ideas, do not take it for granted, you are certainly blessed.

25 minutes ago, swansont said:

Yes, perhaps. That removes classical examples.

But the average position of hydrogen's electron is in the center, and the most probable position is only defined in terms of r, not any of the angles. Nothing is localized any better than that. 

We do not think in terms of velocity of an electron, but realistically even if an electron magically never occupies any space between two points but occupies one point after another point isn't that apparently velocity?

16 minutes ago, swansont said:

Center of mass or charge doesn't tell you the position.

The center of mass and charge of an electron in a hydrogen atom is at the center of the nucleus (neutral charge, so the probability distribution is spherically symmetric). But the odds of you finding the electron there are small.

 

Even for a classical system, or a Bohr orbit (which we know is wrong) where the electron is never in the nucleus, we still have a symmetric system, so the center of mass/charge is the center. It's like saying the earth is inside the sun, because our average position is (roughly) the center of our orbit. It doesn't work.

Would that not involve a span of time? Aren't you saying that the average center of charge is at the nucleus?

Perhaps I should have said instantaneous position?

19 minutes ago, swansont said:

To the extent that this can be applied rigorously (which is to say: not very much) I disagree. Some facts are just complete, and not everything is relative. Some things are invariant. Which is a fact, and (partly because of the qualitative nature of the statement) is absolutely complete.

There are no facts, only logical belief... our beliefs are imperfect, some it would seem more imperfect than others.

On 12/13/2019 at 3:40 PM, MigL said:

The people who arrived at their opinion without reasoning are the D Trump supporters. Not you !

Well, it seems the alternative is to be a Pelosi supporter...

No "facts" are absolutely complete, "Everything is relative".

Can an electron have the property of position via center of charge and/or center of mass?

9 minutes ago, Strange said:

I guess I have to take that as a compliment.

No. (I guess that would be metaphysics, not quantum physics.)

I think the first definition is rubbish as well.  

Quantum physics is really just the study of systems that are described by wave equations with quantised values. It only studies things that exist. And things at a quite a wide range of scales are quantised so it is not just about the "smallest of the small". 

But quantum theory does not seem to be relevant to anything you have discussed; we don't have a quantum theory of gravity. And so gravitational waves are not quantised.

Good information as usual... From all of you.

1 hour ago, Strange said:

It doesn't unify them. But it is another example of the well-known analogies between them.

You are a thinker Strange, even more so than a learner... a question for you: quantum physics I have seen described as seeking the smallest of the small, the quanta... isn't it more correct today to describe it as seeking the threshold between existence and nonexistence?

1 hour ago, Strange said:

It is pretty much static. But the Earth doesn't generate gravitational waves, as far as I know. (Although the Earth-Moon system will.)

What is "am"?

Sorry, EM.

29 minutes ago, Janus said:

Someone falling is responding to the  gravitational field, not gravitational waves. 

 

Just a matter of amplitude and peridocity, the earth's gravitational field is not static. Gravitational waves are a phenom in the gravitational field... You get the point. What is the nature of the effect, not the amplitude of the effect.

38 minutes ago, Strange said:

That doesn't have anything to do with gravitational waves. Although gravitation generally interacts weakly with matter. Look at the enormous mass that needs to be under the ladder for them to be hurt by the fall.

But if you want to quantify the interaction, you could look at this, for example: https://arxiv.org/abs/1110.0408 or https://link.springer.com/article/10.1007/BF02748651

The effect of gravitational waves is different from gravity. I'm not sure the frequency makes much difference. I'm guessing it would interact less because the matter is not likely able to move (compress and expand elastically) at those speeds.

I think it is to do with the stress-energy tensor being second order (but at that point I no longer know what the words mean!)

There has been some theoretical work on very high frequency gravitational waves, for example: https://arxiv.org/abs/1608.03186

I would assume that if the source of the waves have a very much smaller mass than the object you are considering, then the gravitational waves will also be relatively minute or even insignificant. Therefore you can approximate the effect as ... zero.

Good link! Comes very close to unifying am and g does it not? 

Again what is the nature of the effect, not the amplitude... Perhaps I should not have stated such a relationship.

6 minutes ago, YJ02 said:

hopefully you don't believe I think the earth is flat do you?

 

i agree nothing can be proven, but the fact the earth is a sphere and there is no dome we hit as we try to go to orbit, has been pretty well established via direct observation by now.

same with most of what  I listed

yes, i had some spec stuff on there (as in spec because it doesn't exist yet, but these ppl are getting ahead of it,so to speak. like with the 'dangers' of quantum computing) but everything else, I BELIEVE to be true and maybe we don't have all the aspects of the 'why' down or fully understood yet, but that does not keep the majority of us from not accepting the fact.

 

thanks!!  

Replace "fact" with "logical belief". You could say that for flat earth believers, that their science is lacking in evidence.

Columbus speculated that the earth was round because of his observations, there could have been alternative explanations... However he had the interest and intellect to pursue evidence to further the logical belief.

23 minutes ago, Strange said:

Gravitational waves interact very weakly with matter

"weakly" is subjective, ask some one who falls off a ladder how weakly they hit the floor...

The question is not how much matter is affected, but rather ion what way?

The Ghz range wave would have a much different effect than earth's gravitational field did on the man falling off the ladder.

18 minutes ago, Strange said:

You can do a simple calculation based on the orbital speed (and hence time for one revolution) for a system of two masses, just using Newton's equations. This will not be completely accurate for two very large masses in close proximity (like two black holes about to merge, where you would need to use GR) but should be good enough to calculate the frequency and hence wavelength of the generated gravitational waves.

(Note that the accurate result using GR cannot be calculated; you would need to simulate it.)

It is good enough because of the size of the system, a system generating gravitational waves in the Ghz range would be incredibly small and these calculations are no longer good enough... But like I said, let us leave this discussion for later.

21 minutes ago, swansont said:

At the quantum level you don't have trajectories, and I don't think you can say that t = 1/g

True and we can discuss this later.

21 minutes ago, swansont said:

No idea, though I strongly suspect it also depends on the amplitude.

The magnitude of the effect would depend on amplitude, not the nature of the effect.

Come on Swan, your mind can do better than "No idea".

34 minutes ago, Strange said:

You are not dealing with the quantum level; you are talking about gravitational waves. A classical (non-quantum) phenomenon. And time is not subjective in quantum theory.

Gravitational waves interact very weakly with matter, so they would pass through without being absorbed. But they would cause the space the matter is in (and hence the matter, I assume) to be stretched and compressed in directions orthogonal to the direction of travel of the gravitational waves. Exactly how depends on the polarization which, in turn, depneds on the nature of the source; some nice images here: http://www.johnstonsarchive.net/relativity/pictures.html

 

Indeed! Do we know of any other forces that have such an effect on matter?

5 hours ago, swansont said:

A light wave can be any size, so this doesn't really mean anything.

But if you're going to tackle physics problems, you should be able to answer what the orbital period/frequency is for a system of a given size

Yes, a very simple calculation? No... at this quantum level time is subjective. It can be said that t =1/g. But before we get into that discussion...

Let me simplify the question... What effect would a gravitational wave with a frequency in the Ghz range (unreasonable as it may be) have on matter. 

First off, there is no truth... Nothing can be proven, that is the nature of science, there is only logical belief. Those that are limited in understanding, for whatever reason, be it intellect, interest, or religious belief... whatever, cannot or will not pursue the logic, they build a framework that works via trial and error. If believing the world is flat works for you, go with it.

14 minutes ago, MigL said:

We try to fight a little battle against the spreading ignorance on this forum

Indeed you do!

32 minutes ago, swansont said:

Not sure why you say “no such thing”

Gravity would oscillate in a region of space near any pair of bodies that are orbiting each other. 50 GHz would be unreasonable, however.

Ahh, I agree! What if the orbiting system was smaller than a light wave?

Okay, I know... No such thing, but just for the sake of discussion, let's entertain the idea that there was such an entity and it was oscillating in the range of say 50Ghz and that the affected entity had a mass of say 10 million times that of the average apparent mass of the affecting entity.

What would the affectation be?

If a region of space had an oscillating gravitational field, how would this affect a massive body in it's proximity?

A field is something, even a "flat" field has propertie(s), granted the field must be affected for evidence of those properties.

Which came first, the chicken or the egg?

Before we are born a myriad of variables are manipulating the basic design presented by DNA, indeed even the DNA of the gametes is undergoing some modification prior to conception.

10 minutes ago, StringJunky said:

Are notions of size and having a discrete existence, i.e particle-like, meaningful at that level when things are actually excitations in fields?

What constitutes a field?