Consequences of a negative mass universe

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Discussion Overview

The discussion explores the hypothetical implications of a universe where all mass is negative, examining the potential consequences on physical laws, forces, and the nature of matter. Participants consider various aspects such as the behavior of negative mass atoms, the interaction of forces, and the overall stability of such a universe.

Discussion Character

  • Exploratory
  • Debate/contested
  • Conceptual clarification

Main Points Raised

  • One participant questions the definition of "negative mass," distinguishing it from anti-matter, which does not possess negative mass.
  • Another participant emphasizes that the scenario is hypothetical and asks what would happen if mass were negative in all equations.
  • Concerns are raised about the implications of negative mass on fundamental equations, such as F=ma and E=mc², suggesting that they could lead to nonsensical outcomes.
  • A participant proposes that gravity would become repulsive in a negative mass universe, noting that negative mass would result in objects accelerating in the opposite direction of the applied force.
  • There is speculation that the same logic regarding forces would apply to other fundamental interactions, potentially leading to instability in matter.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the implications of negative mass, with multiple competing views and uncertainties remaining about the nature of forces and stability in such a universe.

Contextual Notes

The discussion highlights limitations in understanding the physical meaning of negative mass and its effects on established equations, with unresolved questions about the implications for energy and force interactions.

olso4051
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If a universe existed where all the mass was negative but everything else was the same as our universe in terms laws of physics what would happen? To be more specific it appears that all the mass would repel each other, would negative mass atoms form, would these particles absorb or emit light? What else might be interesting about this universe?
 
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What is "negative mass" ? Anti-matter, which is the only thing I can think of that you might mean, does not have negative mass.
 
Well right it would be a hypothetical situation, and you're right it would not be anti-matter. In every equation you can think of the mass would have a negative value, what would happen?
 
If unicorns existed, they would have horns.

I mean, really ... if you want to just make stuff up, then make up whatever characteristics you like. It has nothing to do with physics.
 
olso4051 said:
Well right it would be a hypothetical situation, and you're right it would not be anti-matter. In every equation you can think of the mass would have a negative value, what would happen?

It's important to realize that our equations describe the real universe. I wouldn't expect negative mass to still use the equation F=MA do relate force, mass, and acceleration. For example, if you put -M in there, does that mean you are applying a negative force now? What does it physically mean? Is the acceleration negative?

E=MC2, how could you possible have negative energy? What does that even mean?

See what I mean? It just leads to nonsense.
 
Gravity would be repulsive, kind of...

F=GmM/r2 so if both masses were negative then F would still be positive, however...

F=ma so a=F/m

F would still point downward but since m is negative a would be negative so an object would accelerate in a direction opposite the force, so upward.

I suspect the same logic would apply to the other forces which hold stuff together so stable matter would not be possible in a universe with negative mass. In such a universe there would be no one to wonder what would happen if the sign of mass were opposite.
 

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