If you could make your mass=0, would you begin moving at c?

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In summary, the conversation discusses the concept of zero-mass objects and whether they can travel at speeds other than the speed of light, or if they can be stationary. It is mentioned that in an environment with no outside influences, an object with zero mass would remain stationary and have zero energy. The concept of Mach's Principle is brought up and it is suggested that an object's mass and movement can only be determined by comparing it to other objects. The conversation also touches upon the idea that a photon, being massless and stationary, may not truly exist in an empty universe.
  • #1
Meatbot
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Ok...we don't know of any way to do this, but let's assume we found a way for a second.

Would you require something to give you a push before you began moving at c or would you just instantly acquire that velocity? In what direction would you begin moving?

Must all zero-mass objects travel at c or can some travel slower, or be stationary? What if you were in an environment with no outside influences and you acquired zero mass? With nothing to push you, would you remain stationary? If you did, would you have zero energy?
 
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  • #2
No, they all have to travel at c.

(If they are an imaginary particle, like a piece of classical vacuum, they can do whatever they want.)
 
  • #3
Meatbot said:
Must all zero-mass objects travel at c or can some travel slower, or be stationary? What if you were in an environment with no outside influences and you acquired zero mass? With nothing to push you, would you remain stationary? If you did, would you have zero energy?

That's a different ballgame altogether. Read up a bit on Mach's Principle, if you already haven't. Then we will discuss.
 
  • #4
Shooting star said:
That's a different ballgame altogether. Read up a bit on Mach's Principle, if you already haven't. Then we will discuss.

I read up on it. Seems to me that if we imagine a universe in which the only object is one photon, then since there is no way to know if it is moving it can be said to be stationary. If a photon is massless and stationary then I would think it has no energy. I'm not sure how it can even be said to exist in that case. So I would think a photon can't exist unless there is something else in the universe with which to measure it's velocity against.

So I think that if a quark is alone in the universe and acquires zero mass it would cease to exist.
 
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  • #5
Let's forget the photon for a while and say that an atom is there in a so called empty Universe. What about the speed of the atom, or the mass of the atom? Can it be said to exist in this case?
 
  • #6
Shooting star said:
Let's forget the photon for a while and say that an atom is there in a so called empty Universe. What about the speed of the atom, or the mass of the atom? Can it be said to exist in this case?

Well, you couldn't tell if or whether it was moving since there's nothing to compare it to. I guess you can only tell the mass by it's effect on other mass or by trying to push it and see how it accelerates. But if you can't tell if it's moving since there's no other matter then you can't tell how it's accelerating. So I guess you can't *determine* the mass, but does that mean it's not there? I don't know but if it was still there it would still have energy so I think it could still be said to exist. I think a photon is different because it's defined as having no mass. No mass and no movement equals no energy. That would seem to indicate it's not there, or that it is there but has some other properties that we can't access.
 
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  • #7
But in this case, there are constituents of the atom, and the motion of an electron may now be compared with that of the nucleus. This Universe is a bit different from the Universe with only a photon. The constituents may impose "mass" on one another, in a Machian way. The reason I wanted you think about an atom is that we know a bit about the structure of atoms, but not of the photons in the same sense.

> So I guess you can't *determine* the mass, but does that mean it's not there.


If it cannot be determined in principle, then it's not there.

What you are trying to say that a particle may exist in an empty Universe, even though we can't determine it's mass etc., but a photon cannot exist at all. Is that right?

>... or that it is there but has some other properties that we can't access.

That's a more constructive vein of thought.
 
  • #8
Shooting star said:
What you are trying to say that a particle may exist in an empty Universe, even though we can't determine it's mass etc., but a photon cannot exist at all. Is that right?
Yeah...that's the idea.
 

Related to If you could make your mass=0, would you begin moving at c?

1) What does it mean to have a mass of 0?

Having a mass of 0 means that there is no physical matter or substance present. In other words, the object would have no weight or density.

2) Would an object with a mass of 0 be able to exist?

No, it is not possible for an object to have a mass of 0. All objects, even particles, have some level of mass.

3) How is mass related to movement?

Mass is a fundamental property of matter that determines how it interacts with other objects. The more massive an object is, the more force is required to move it. Objects with a larger mass will require more energy to reach the speed of light, or c.

4) Can an object with a mass of 0 move at the speed of light?

No, even if an object had a mass of 0, it would still require an infinite amount of energy to reach the speed of light. This is because the speed of light is a constant and cannot be surpassed by any object with mass.

5) How does the concept of mass equaling 0 relate to Einstein's theory of relativity?

Einstein's theory of relativity states that the speed of light is the same for all observers, regardless of their relative motion. This means that no object with mass can reach the speed of light, as it would require an infinite amount of energy. Therefore, the concept of an object with a mass of 0 moving at the speed of light is not possible in accordance with this theory.

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