Can Objects Travel at the Speed of Light?

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SUMMARY

The discussion clarifies that the commonly understood law stating "no object can travel at or above the speed of light" is fundamentally based on the inability of objects with mass to accelerate to light speed. It is established that objects with zero rest mass, such as photons, must travel at the speed of light. Furthermore, any hypothetical object created with a speed exceeding light would need to maintain that speed, which would lead to violations of causality, suggesting such objects cannot exist within our current understanding of physics.

PREREQUISITES
  • Understanding of special relativity principles
  • Knowledge of mass-energy equivalence
  • Familiarity with the concept of causality in physics
  • Basic comprehension of particle physics, specifically regarding massless particles
NEXT STEPS
  • Research the implications of special relativity on mass and speed
  • Explore the properties and behavior of massless particles like photons
  • Study causality and its role in theoretical physics
  • Investigate hypothetical particles, such as tachyons, and their theoretical implications
USEFUL FOR

Students of physics, educators, and anyone interested in the fundamental laws governing motion and the speed of light in the context of modern physics.

KingNothing
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I am not an expert on Physics and have for the past year been engulfed in work, so I am very rusty. I read a comment online recently that essentially said the laws of physics simply prevent any object from accelerating to the speed of light (infinite energy required?), but do not say that an object traveling at the speed of light would necessarily be violating physical laws.

Is it true that the commonly-understood law that "no object can travel at or above the speed of light" is derived entirely from an inability of said object to accelerate to the speed of light?
 
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Hi KingNothing! :smile:
KingNothing said:
Is it true that the commonly-understood law that "no object can travel at or above the speed of light" is derived entirely from an inability of said object to accelerate to the speed of light?

Yes.

An object of zero rest-mass must travel at the speed of light.

Any object that was created with speed faster than light would have to stay faster than light (for the same reason … it can't be accelerated down to the speed of light) …

however, such objects would violate causality, so we believe they can't exist. :wink:​
 
Thank you kindly Mr. tiny-tim!
 
Your Majesty is most gracious. :smile:
 

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