# Charge Interaction

1. Nov 23, 2013

### PhyHunter

Charge attraction

Hi
I googled why different charges attrack each other and I found severel answer but I guess this answers are not true because there is no info about in wikipedia or there is no mathematicaal explanation.I want to know these theories are true or not or this theory is just
hypothesis.

Thanks

2. Nov 23, 2013

### dauto

Yes, opposite charges do attract each other. That's an empirical fact. It doesn't require an explanation. Your question seems to ask us whether or not an unnamed theory is true. How are we supposed to answer that question if you don't tell us what theory you're talking about? Finally, when did wiki become the final word on whether something is true or not?

3. Nov 23, 2013

### PhyHunter

I dont know the name of theory.But I have an explanation I cut it from somewhere.This idea is tro ur not or whats the name of this theory.
Thanks

The easiest way to understand this is perhaps not with Quantum mechanics and virtual photons. The ball & momentum analogy works (sort of) for repulsion, but not at all for attraction, so the end result may just be more confusion.

Think fields instead. You have most likely seen a picture of how the sun "bends" space-time and creates curvature in the field. You can use the same image to visualize how charges "bend" the electromagnetic field. For instance let's say that a negative charge would bend the field downwards - like the sun would space-time - and a positive charge would have the opposite effect and bend the field upwards. In a sort of volcano-like fashion perhaps =) ...

Now. The field does not like to be bent. The default state of any field is uncurved, and any curvature in the field will always result in a force trying to even the field out. Many things in nature work like this, always striving for it's "normal state" or the most energy-efficient one.

So. When two charges are close enough to each other, their fields will interact. Two of opposite charge will neutralize the field in between the charges resulting in a net "external pressure" pushing them together. Two like charges will instead add more stress to the field in between them resulting in a net "internal pressure" pushing them apart. Perhaps this is a bit harder to visualize.

But whether you can visualize it or not doesn't matter. The important thing to understand is that there is a very fundamental principle of nature at work here.

4. Nov 23, 2013

### PhyHunter

Here the explanation of this theory.Its true or not ?
Whats the this theory name ?
Thanks

The easiest way to understand this is perhaps not with Quantum mechanics and virtual photons. The ball & momentum analogy works (sort of) for repulsion, but not at all for attraction, so the end result may just be more confusion.

Think fields instead. You have most likely seen a picture of how the sun "bends" space-time and creates curvature in the field. You can use the same image to visualize how charges "bend" the electromagnetic field. For instance let's say that a negative charge would bend the field downwards - like the sun would space-time - and a positive charge would have the opposite effect and bend the field upwards. In a sort of volcano-like fashion perhaps =) ...

Now. The field does not like to be bent. The default state of any field is uncurved, and any curvature in the field will always result in a force trying to even the field out. Many things in nature work like this, always striving for it's "normal state" or the most energy-efficient one.

So. When two charges are close enough to each other, their fields will interact. Two of opposite charge will neutralize the field in between the charges resulting in a net "external pressure" pushing them together. Two like charges will instead add more stress to the field in between them resulting in a net "internal pressure" pushing them apart. Perhaps this is a bit harder to visualize.

But whether you can visualize it or not doesn't matter. The important thing to understand is that there is a very fundamental principle of nature at work here.

5. Nov 23, 2013

### Baluncore

It is a mistake to rely on wikipedia. Science is peer reviewed, wikipedia is crowd sourced.

“Opposite charges attract” was once only a working hypothesis, but it has matured and is now accepted by science as fact because it has never been demonstrated to be a false hypothesis.

Acceptance of a scientific “fact” or “law” is initially more important than an advanced understanding of why that law holds.

The “reason” why charges attract is dependent on the model you are considering. There is often no convenient mechanistic explanation and physicists must resort to mathematical models without any analogous human physical experience.

For example, two opposite charges have an electric field between them. That field has a gradient. The more positive charge is higher than the more negative charge. The more positive charge “wants” to slide down the gradient while the more negative charge “wants” to slide up. While this gives the shallow explanation of “opposite charge attraction”, it can not be reliable and will cause all sorts of problems later if it cannot be replaced by a mathematically defined relationship.

6. Nov 23, 2013

### dauto

The theory of virtual particles is actually the better theory. Why do you say it doesn't work for attraction? The other theory has some correct features (The tendency for a system to move towards a state of lower energy, for instance), But it also has some vague statements about bending fields and fields not liking to be bend that don't seem particularly meaningful or helpful to me.

7. Nov 23, 2013

### WannabeNewton

It is, in a sense, a consequence of QFT. See section 1.5 of Zee "Quantum Field Theory in a Nutshell".

8. Nov 24, 2013

### PhyHunter

First thing its complicated.Second think its not a law.Third think threre's no really study in this subject

9. Nov 24, 2013

### PhyHunter

So we can not say this theory is true

10. Nov 24, 2013

### Staff: Mentor

I wouldn't call any theories "true" or "false". Only more of less accurate. Gravity according to Newton could be considered technically "false", yet we still use it to calculate interplanetary trajectories for our spacecraft because it is accurate enough and much easier to use than General Relativity. Think of it as a shortcut.

Similarly, our theories on how subatomic particles interact is accurate to the best of our measuring capabilities at this time. It could turn out that the theories are "false" in the future, but right now we don't know.

11. Nov 24, 2013

### PhyHunter

I am agree with you.We cant say true o false so this theory is less accurete.

12. Nov 24, 2013

### JayJohn85

Would they not have arrived at this conclusion intuitively through their works with magnets? Or am I just grasping at straws here?

13. Nov 24, 2013

### PhyHunter

Its about virtual photons I guess.But in my estimation they could not prove it.

14. Nov 24, 2013

### Staff: Mentor

You're grasping as straws. The failure of classical physics to work at the atomic and subatomic level was known 100 years ago and is why Quantum Mechanics was first created.

Proofs only exist in math.

Less accurate than what? To my knowledge, QED and other theories that use virtual particles are the most accurate theories we've ever had to explain the way fundamental particles interact.

15. Nov 25, 2013

### PhyHunter

I dont agree with you..Like newton, their ıdeas about gravitational is works like QED but Einstein has found a GR which its more beautiful and more accurate then Newtonian gravity so QED can be false.In my opinion the QED or Quantum is just a illusion which Einstein thought.

16. Nov 25, 2013

### ZapperZ

Staff Emeritus
This is now no longer physics, but rather a beauty contest. Thread closed.

Zz.