Speed of light and relations to mass

Click For Summary

Discussion Overview

The discussion revolves around the implications of accelerating objects approaching the speed of light, particularly focusing on the relationship between speed, mass, and energy requirements. Participants explore theoretical concepts related to relativistic mass and energy in different inertial frames of reference.

Discussion Character

  • Debate/contested
  • Conceptual clarification
  • Technical explanation

Main Points Raised

  • One participant suggests that achieving the speed of light would require infinite energy due to the increase in mass, proposing a paradox where the fuel source could become infinite, potentially canceling out this barrier.
  • Several participants challenge this idea, asserting that the increase in mass is only apparent from an external inertial frame and does not affect the rocket's frame of reference.
  • A later reply clarifies that the mass increase is perceived differently depending on the observer's frame of reference, emphasizing the importance of understanding "frame of reference" in this context.

Areas of Agreement / Disagreement

Participants express disagreement regarding the implications of mass increase at relativistic speeds, with some supporting the idea of infinite energy requirements and others emphasizing the perspective-dependent nature of mass in different frames of reference.

Contextual Notes

The discussion does not resolve the complexities surrounding the definitions of mass and energy in relativistic physics, nor does it address the assumptions underlying the claims made by participants.

chgol5270
Messages
6
Reaction score
0
Being that anything accelerated to the speed of light gains infinite mass and will require infinite energy thus providing a barrier to achieving the speed of light but wouldn't the fuel source become infinite and in turn the potential for energy become infinite effectively canceling out this barrier.
 
Physics news on Phys.org
Nope.
 
ghwellsjr said:
Nope.

Well said.
 
The increase in mass of the fuel is apparent only in another inertial frame. In the frame of the rocket it stays the same (decreasing as it is used up).
 
mathman said:
The increase in mass of the fuel is apparent only in another inertial frame. In the frame of the rocket it stays the same (decreasing as it is used up).

is what you're saying is that the increase in mass isn't from the perspective of said object ie. "rocket" but from the perspective of outside observations?
 
chgol5270 said:
is what you're saying is that the increase in mass isn't from the perspective of said object ie. "rocket" but from the perspective of outside observations?

Yes, that is exactly what he is saying, and not just any "outside observations" but those that are taken from an inertial frame of reference that is moving rapidly from the point of view of the rocket. Look up "frame of reference".
 

Similar threads

Undergrad A question about the speed of light and electromagnetism
  • · Replies 51 ·
2
Replies
51
Views
5K
High School c^2 in Einstein‘s theory of relativity
  • · Replies 10 ·
Replies
10
Views
2K
High School Speed of light and this Accelerating Rocket scenario
  • · Replies 45 ·
2
Replies
45
Views
5K
High School What if we use a non physical reference point to measure an object's mass?
  • · Replies 5 ·
Replies
5
Views
1K
High School Why does it require an infinite amount of energy to reach the speed of light?
  • · Replies 130 ·
5
Replies
130
Views
16K
High School Thought Experiment : Try and get Alice to "0%" the Speed of light
  • · Replies 15 ·
Replies
15
Views
2K
High School The expansion of the Universe and time travel (By a non-scientist)
  • · Replies 2 ·
Replies
2
Views
2K
High School Why is the constant speed of light so unique?
  • · Replies 19 ·
Replies
19
Views
2K
High School Gravity and speed of information for orbiting planets
  • · Replies 22 ·
Replies
22
Views
1K
Undergrad Energy contained in fuel in speed of light ship
  • · Replies 31 ·
2
Replies
31
Views
3K