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13. August 2023 14:17
by Admin
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what effects does magnetism have on gravity?

13. August 2023 14:17 by Admin | 0 Comments

 

Magnetism and gravity are distinct fundamental forces of nature and, as currently understood, they do not directly influence each other. Here's a brief breakdown:

Gravity: This is a universal force that acts between all masses. It's responsible for the Earth orbiting the Sun, the moon orbiting Earth, and any object with mass attracting any other object with mass. The strength of the gravitational force depends on the mass of the objects and the distance between their centers. Einstein's theory of General Relativity describes gravity not as a force but as a curvature of spacetime caused by mass and energy.

Magnetism: This is one component of the electromagnetic force, which also includes electricity. Magnets have a north and a south pole, and they can attract or repel other magnets. Electromagnetic forces are responsible for a vast range of phenomena, from holding atoms together in molecules to generating light.

There are no known effects that magnetism has directly on gravity or vice versa, in the sense of altering the strength or behavior of either force. However, there are contexts where both forces are relevant. For instance, certain astronomical objects like neutron stars have both strong gravitational and magnetic fields, but the forces themselves remain distinct.

That said, it's worth noting that our understanding of the universe and its forces is still evolving. There are many questions in physics that remain unanswered, especially when delving into the realms of quantum gravity and the quest to unify the fundamental forces of nature. But as of our last understanding, magnetism and gravity operate independently of each other.

 

is there a spectrum of force as there is with emr?

The concept of a "spectrum" is most commonly associated with electromagnetic radiation (EMR), which describes the range of frequencies (or wavelengths) over which electromagnetic waves can occur—from radio waves to gamma rays. The electromagnetic spectrum has distinct regions based on frequency or wavelength, and each region corresponds to different physical phenomena or uses.

When we talk about forces in nature, particularly the four known fundamental forces (gravitational, electromagnetic, weak nuclear, and strong nuclear), there isn't an analogous "spectrum" of forces in the same way there is for electromagnetic radiation. Each force is qualitatively distinct in its properties, mechanisms, and effects.

Gravitational Force: A long-range force that acts between masses. It is universally attractive and is described by Einstein's General Relativity.

Electromagnetic Force: Includes both electric and magnetic forces. It acts between electric charges and is responsible for holding atoms and molecules together, among many other phenomena.

Weak Nuclear Force: Responsible for certain types of radioactive decay, such as beta decay. It has a very short range, acting at sub-nuclear distances.

Strong Nuclear Force: Holds protons and neutrons together within the nucleus of an atom. Like the weak force, it acts at very short distances.

Each of these forces is distinct, with its own set of principles, equations, and effects. They don't lie on a single continuum or "spectrum" in the way that different frequencies of light do.

However, the quest for a unified theory of everything in physics aims to describe these disparate forces under a single theoretical framework. In some proposed theories, at extremely high energies (such as those just after the Big Bang), these forces may merge or manifest as aspects of a singular force. But such ideas remain speculative and not yet confirmed by experiment as of my last update in September 2021.

 

where does diamagnetism fit in?

Diamagnetism is a type of magnetic response exhibited by all materials, but it is generally weak and often overshadowed by other types of magnetic behaviors in materials that have them. It's part of the broader topic of magnetism, which is an aspect of the electromagnetic force—one of the fundamental forces mentioned earlier.

To give a detailed breakdown:

Diamagnetism: All materials have diamagnetic properties to some degree. In a diamagnetic material, when it is subjected to an external magnetic field, it develops an induced magnetic moment that is opposite in direction to the applied field. This results in a weak repulsion from the applied magnetic field. Diamagnetic materials do not retain this induced magnetic moment once the external field is removed. The classic example of diamagnetic behavior is bismuth, but even water and living creatures (like frogs) can demonstrate diamagnetic behavior under strong magnetic fields.

Paramagnetism: Some materials are paramagnetic, meaning they are weakly attracted to magnetic fields and can be weakly magnetized. Unlike ferromagnets, they don't retain their magnetization once the external field is removed. This behavior arises because of unpaired electrons in atomic or molecular electron configurations.

Ferromagnetism: This is the strong form of magnetism most people are familiar with, as seen in common magnets. Materials like iron, nickel, and cobalt are ferromagnetic. They have domains in which the magnetic moments of atoms or molecules align with one another, and these domains can be aligned with an external field to produce strong magnetization that persists even when the external field is removed.

Antiferromagnetism and Ferrimagnetism: These are other types of magnetic ordering found in certain materials. In antiferromagnets, the magnetic moments of adjacent atoms or ions align in opposite directions, canceling out. In ferrimagnets, the opposing magnetic moments don't cancel out entirely, leading to a net magnetization.

Diamagnetism fits into the broader study of magnetism as one of several possible magnetic responses a material can have when subjected to a magnetic field. It's directly connected to the electromagnetic force, as are all magnetic phenomena.

 

but is diamagnetism the lorenz force?

No, diamagnetism is not the same as the Lorentz force, but the Lorentz force plays a role in the understanding of diamagnetism.

Here's a clarification:

Lorentz Force: This is the force experienced by a charged particle moving in an electromagnetic field. Mathematically, the Lorentz force 

 F on a charge,  q moving with a velocity, v in an electric field,  E and magnetic field, so B is given by:

F=q(E+v×B)

The term �×�v×B represents the magnetic force due to the charged particle's motion in the magnetic field.

Diamagnetism: This is a property of materials that develop a negative magnetic susceptibility in the presence of an external magnetic field. Diamagnetism arises because, when the orbits of electrons around atomic nuclei are exposed to an external magnetic field, they experience a change due to the Lorentz force. This change results in a slight shift in the electron orbits in such a way that they produce an opposing magnetic field (Larmor precession). The net result is that diamagnetic materials are repelled by external magnetic fields.

So, while the Lorentz force itself isn't diamagnetism, it plays a role in the underlying mechanism. In the context of diamagnetism, it's the influence of the external magnetic field on the motion of electrons (specifically, their orbital motion) via the Lorentz force that leads to the diamagnetic response.

 

so its more like van der waals?

Not exactly. Diamagnetism and van der Waals forces are distinct phenomena, but it's understandable to look for analogies or connections between various physical concepts. Let's dive a little deeper:

Diamagnetism: As discussed, diamagnetism arises because of the changes in the motion of electrons in an atom or molecule when exposed to an external magnetic field. This change is due to the Lorentz force acting on the moving electrons. All materials exhibit some degree of diamagnetism, but in most cases, it's overshadowed if the material also has paramagnetic or ferromagnetic properties.

van der Waals Forces: These are a set of forces that arise from fluctuating electric charges in atoms and molecules. There are a few types of van der Waals forces:

London Dispersion Forces: These are weak forces that arise due to temporary fluctuations in the electron distribution around an atom or molecule, which induces a temporary dipole in neighboring atoms or molecules. This is the primary type of van der Waals force and is present between all atoms and molecules.

Dipole-Dipole Interactions: When polar molecules with permanent dipoles come close together, they can attract each other because of the positive end of one molecule being attracted to the negative end of another.

Dipole-Induced Dipole Interactions: A polar molecule can induce a temporary dipole in a neighboring non-polar molecule.

The connection you might be seeing is that both diamagnetism and van der Waals forces deal with electron distributions and their effects. In diamagnetism, an external magnetic field affects electron orbits, creating an opposing magnetic field. In van der Waals forces, fluctuations or distortions in electron distributions around atoms or molecules lead to temporary electric dipoles, which then lead to attractions between atoms or molecules.

While both involve electrons and their distributions, the phenomena are different in nature and arise from different causes. Diamagnetism concerns the interaction of materials with magnetic fields, while van der Waals forces relate to the interactions between neutral atoms or molecules because of transient or permanent electric dipoles.

 

but they are both grouping of like polarity arising in a repulsive force, or not?

I see where you're coming from now. You're highlighting the qualitative similarity in which "like" entities produce repulsive interactions in both contexts. Let's compare:

Diamagnetism:

When an external magnetic field is applied to a material, the electrons in the material adjust their orbital motion in response. This adjustment, due to the Lorentz force, results in a slight change in the magnetic moment of the atom.

This induced magnetic moment is in the opposite direction to the applied external field, leading to a repulsive interaction.

In essence: like magnetic fields (the induced one and the external one) repel each other.

van der Waals Forces (specifically, London Dispersion Forces):

Due to quantum mechanical fluctuations, an atom or molecule can have a temporary imbalance in electron distribution, leading to a temporary electric dipole.

This temporary dipole can induce a dipole in a neighboring atom or molecule.

However, when the dipoles are transient as in London Dispersion Forces, they don't lead to repulsion but rather a weak attraction. The temporary nature and the synchrony in which these dipoles arise and fade is why they attract rather than repel.

On the other hand, permanent dipoles (as in dipole-dipole interactions) can repel if their like poles (positive-positive or negative-negative) face each other.

So, while both phenomena involve "like" entities (whether magnetic moments or electric dipoles) responding to external influences and influencing neighbors, their outcomes differ:

Diamagnetism always leads to a repulsive response to an external magnetic field.

van der Waals forces can lead to attraction (as with induced dipoles in London Dispersion Forces) or, in the case of permanent dipoles facing like poles, repulsion.

Your observation is interesting in that it touches on a recurring theme in physics: similar patterns or behaviors emerging in different contexts. However, it's essential to note the specifics and differences to fully appreciate each phenomenon.

 

So how did the frog levitate?

Ah, I see the connection you're drawing now! The levitating frog is a famous demonstration of the power of diamagnetism.

In the late 1990s, researchers in the Netherlands performed an experiment in which they levitated a live frog using a very strong magnetic field. This was done using a powerful superconducting magnet that produces a magnetic field with a gradient. Here's how it worked:

Diamagnetism in Living Organisms: All materials, including water and the organic materials inside living organisms, exhibit some degree of diamagnetism. This means that they will generate a weak opposing magnetic field when exposed to an external magnetic field.

Strong Magnetic Field: The experimenters used a superconducting electromagnet capable of producing a magnetic field more than 10,000 times stronger than that of a typical refrigerator magnet. Such a strong magnetic field results in a noticeable diamagnetic response even from weakly diamagnetic materials.

Magnetic Field Gradient: Just having a strong magnetic field isn't enough to levitate the frog. The key was creating a gradient in the magnetic field. This means that the strength of the magnetic field changes over a short distance. When the frog is placed in this gradient, the magnetic force due to its diamagnetism is stronger on the side closer to the stronger part of the magnetic field. This results in a net upward force—opposing gravity—that levitates the frog.

The levitating frog experiment visually demonstrated that diamagnetism, while usually a very weak effect, can produce dramatic results under the right conditions. This effect isn't limited to frogs; theoretically, any object can be levitated with a strong enough magnetic field and gradient, given the diamagnetic properties inherent in all matter. However, the conditions required make it impractical for most purposes beyond specific research settings.

 

And it is just a angular moment of the lorentz force that does this?

The levitation of the frog (or any other diamagnetic object) in a strong magnetic field is indeed linked to the Lorentz force, but it's more accurate to say that the underlying cause is the change in the atomic-scale magnetic moments induced by the external magnetic field. The Lorentz force plays a role in this induction. Here's a more detailed breakdown:

Electrons in Atoms: Electrons orbiting atomic nuclei and spinning on their own axes produce tiny magnetic moments. Normally, these magnetic moments are oriented randomly in a material, so there's no net magnetic field produced by the material.

Effect of External Magnetic Field: When a magnetic field is applied to a material, the field exerts forces on these moving electrons due to the Lorentz force. Specifically, the force is a result of the velocity of the electrons (their orbital and intrinsic spin motion) interacting with the external magnetic field.

Change in Electron Paths: The Lorentz force, which acts on these moving electrons, changes their paths. This alteration in the electron paths results in a modification of the magnetic moments of the atoms or molecules in the material.

Opposing Magnetic Field: The change in the atomic or molecular magnetic moments induced by the external field results in the generation of a weak opposing magnetic field by the material. This is the essence of diamagnetism.

Levitation: If the magnetic field has a gradient (changes over distance), the force it exerts on the diamagnetic material varies across the object. This variation can create a net force in the direction opposing gravity (or any other external force), leading to levitation.

To summarize, while the Lorentz force is indeed fundamental to understanding why materials exhibit diamagnetic behavior when placed in a magnetic field, the actual levitation arises from the interplay of the induced diamagnetic response and the gradient of the magnetic field. The angular momentum or changes therein (often referred to as Larmor precession in this context) of the electrons is a crucial aspect of this induced response.

 

I still think there are more similarities to van der waals here. We are still getting forces that are normally equally distributed (chaotic) in all directions to team up and act as one. 

Your perspective is certainly thought-provoking. Let's delve a little deeper into the similarities and the essence of what you're describing.

Emergent Order from Chaos: Both van der Waals forces (specifically the London dispersion component) and diamagnetism involve phenomena where forces that are usually random or chaotic on average "team up" due to external influences.

In diamagnetism, an external magnetic field influences the orbiting electrons in such a way that they produce an opposing magnetic field, turning what would otherwise be a chaotic system of magnetic moments into a system where there's a coordinated, though weak, response.

In London dispersion forces, temporary fluctuations in the electron distribution lead to the creation of instantaneous dipoles, which then induce dipoles in neighboring atoms or molecules. This turns what would usually be random electron distributions into correlated fluctuations, resulting in an attractive force between the entities.

Response to External Stimuli: Both phenomena involve responses to external influences.

In the case of diamagnetism, it's an external magnetic field.

In the case of London dispersion forces, it's the presence of other nearby atoms or molecules and their influence via their own electron distributions.

Quantum-Mechanical Origin: Both phenomena have their roots in quantum mechanics. For instance:

Diamagnetism is influenced by the principles of quantum mechanics that dictate electron behavior and their responses to magnetic fields.

London dispersion forces are due to the quantum mechanical probability clouds of electrons and the fluctuations therein.

The similarities you've pointed out reflect a deeper theme in physics, and perhaps in nature as a whole: systems often transition from a state of chaos or disorder to a state of order or coordination under the influence of external factors.

However, while these themes or patterns recur, the specifics of each phenomenon and the mechanisms behind them vary. It's always a balance between recognizing overarching similarities and understanding the nuances that make each phenomenon unique.

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