Notion of a zero dimensional point particle?

In summary, a particle can have its properties spread out in a finite volume, but can be shrunk down to increasingly smaller volumes when measured.
  • #1
Nickyv2423
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When we say a fundamental particle is 0 dimensional, is that literal or figurative?
Is it physically possible that a particle has it's properties (like charge, mass) spread out in a finite volume, but can be "shrunk" to increasingly small volumes when we measure it?
 
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  • #2
Nickyv2423 said:
When we say a fundamental particle is 0 dimensional, is that literal or figurative?
It is a mathematical model. Strictly speaking it means that the classical extent of the particle in space has no clear meaning in QM.
The "size" of a particle depends on the interaction and is given by a quantity called the cross-section.
The location of the particle in space is given by a probability distribution which tells you the chance of detecting the particle within a particular volume within a particular time period.

Is it physically possible that a particle has it's properties (like charge, mass) spread out in a finite volume, but can be "shrunk" to increasingly small volumes when we measure it?
The statistics of the particle may, in principle, be arbitrarily tightly located - yes.
For example: if the position is described by a Gaussian distribution, then the standard deviation of that distribution may be arbitrarily small.
 
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  • #3
My way of looking at it is that the particle has no intrinsic spatial properties. Spatial properties like location (and even size), for instance, are meaningful only in another entity's context (such as an observer).
 
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  • #4
mikeyork said:
My way of looking at it is that the particle has no intrinsic spatial properties. Spatial properties like location (and even size), for instance, are meaningful only in another entity's context (such as an observer).
... or in the context of an interaction, or a confining potential, either of which could qualify as an observer.
 
  • #5
MonteCristo said:
There is absolutely no way in which the particle can exist in a zero dimensional plane
Well, that's true but not for the reason you think.

Your "zero dimensional plane" is an oxymoron - a plane consists of two dimensions.
But that's not what the OP is talking about.

MonteCristo said:
as it needs an actual base of existence in a dimension,
Can a two-dimensional plane inhabit three-dimensional space? Sure. The plane that divides my pretty neighbour's property from mine.
Can a one-dimensional line inhabit three-dimensional space? Sure. The line of sight between my land-scope and my neighbour's kitchen window. Anything that intersects that line intersects my sight line.
Can a zero-dimensional point inhabit a three-dimensional plane? Sure. The focus of the eyepiece that I'm using to ensure my neighbour is safe from creeps.
 
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FAQ: Notion of a zero dimensional point particle?

1. What is a zero dimensional point particle?

A zero dimensional point particle is a theoretical concept in physics that refers to an object with no dimensions in space or time. It is often used as a simplified model for particles such as electrons or photons.

2. How is the notion of a zero dimensional point particle used in science?

The notion of a zero dimensional point particle is used in science as a mathematical construct to simplify complex physical systems. It is often used in theories such as quantum mechanics and relativity to describe the behavior of particles at a microscopic level.

3. Is a zero dimensional point particle a physically real object?

No, a zero dimensional point particle is not considered to be a physically real object. It is a theoretical concept that is used to describe the behavior of particles at a microscopic level, but it does not have a physical existence in the same way that macroscopic objects do.

4. What are the limitations of the notion of a zero dimensional point particle?

The notion of a zero dimensional point particle has several limitations. It does not take into account the particle's internal structure or interactions with other particles, and it cannot fully describe the behavior of particles in all physical situations.

5. How does the concept of a zero dimensional point particle relate to the concept of a singularity?

The concept of a zero dimensional point particle is closely related to the concept of a singularity, which is a point in space where the laws of physics break down. In some theories, such as general relativity, singularities are described as having zero dimensions and infinite density, similar to the notion of a zero dimensional point particle.

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