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

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Discussion Overview

The discussion revolves around the hypothetical scenario of acquiring zero mass and its implications on motion and existence in a universe with no external influences. Participants explore concepts related to massless objects, energy, and the philosophical implications of existence without reference frames.

Discussion Character

  • Exploratory
  • Conceptual clarification
  • Debate/contested

Main Points Raised

  • Some participants question whether a zero-mass object would require an initial push to begin moving at the speed of light (c) or if it would instantly acquire that velocity.
  • One participant asserts that all zero-mass objects must travel at c, while noting that imaginary particles might behave differently.
  • There is a discussion about the implications of Mach's Principle on the existence and measurement of mass and motion in an empty universe.
  • Another participant suggests that if a photon is massless and stationary, it may have no energy, raising questions about its existence without a reference frame.
  • Participants consider the existence of an atom in an empty universe and whether its mass and speed can be determined without external comparison.
  • One participant argues that while an atom may exist, its properties cannot be determined in isolation, contrasting this with the case of a photon.
  • There is a suggestion that the constituents of an atom may impose mass on one another, leading to different implications than those for a photon.
  • Some participants express uncertainty about the existence of particles in an empty universe, particularly regarding photons and their properties.

Areas of Agreement / Disagreement

Participants express differing views on the existence and properties of massless objects, particularly photons, in an empty universe. There is no consensus on whether such objects can exist or how their properties can be defined without reference frames.

Contextual Notes

The discussion involves assumptions about the nature of mass, energy, and existence in theoretical scenarios, which remain unresolved. The implications of Mach's Principle and the definitions of massless particles are also not fully explored.

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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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.)
 
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.
 
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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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?
 
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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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.
 
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.
 

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