Answer to light speed travel is E=mc2 itself?

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Discussion Overview

The discussion revolves around the implications of Einstein's equation E=mc² in the context of traveling at light speed. Participants explore the relationship between energy, mass, and velocity, particularly focusing on the concept of relativistic mass and the energy requirements for acceleration as an object approaches light speed.

Discussion Character

  • Exploratory
  • Debate/contested
  • Technical explanation

Main Points Raised

  • One participant suggests that as an object's speed increases, its mass increases, leading to the idea that infinite energy would be required to reach or exceed light speed.
  • Another participant counters that energy content is not based on mass but rather on chemistry, implying that the relationship is more complex than simply mass increase.
  • A different viewpoint argues against the concept of increased mass at high velocities, stating that one would not perceive any change in mass without a comparative frame of reference.
  • It is noted that as an object accelerates towards light speed, it requires exponentially more energy for further acceleration, which is linked to the concept of relativistic mass.
  • One participant questions the feasibility of harnessing energy from a moving object to increase its velocity, suggesting that attempting to do so would result in slowing the object down rather than achieving a net gain in speed.

Areas of Agreement / Disagreement

Participants express differing views on the concept of relativistic mass and the implications of E=mc² for energy and velocity. There is no consensus on whether mass increases with speed or how energy can be harnessed from a moving object.

Contextual Notes

Participants reference the concept of relativistic mass and its implications, but there are unresolved assumptions regarding the definitions and interpretations of mass and energy in different frames of reference.

fredk91
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First off, I'm new here so if this is in the wrong section I apologize. Now to the question:
As dumb as this may sound to people that know more about physics then me (I'm a med student but I find myself reading about physics time to time) it makes perfect sense in my head (due to lack of knowledge most likely), anyway, I was once told a simple way to understand E=mc2, "if something is going at 10mph, it doesn't simply take twice the energy to go twice as fast, it requires exponentially more energy. As such, the faster you go, the heavier the object gets. So in order to get to lightspeed, you would need infinite energy, to get past lightspeed you would need infinite energy+x". Now for the question, couldn't the fact that the weight of the object moving is increasing infinitely somehow be used to create infinite energy? ie something moving 100mph weighing 100lbs could generate 100 units of energy and that energy could be used to move it at 101mph weighing x lbs which would then generate x units of energy etc?
 
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In your reference frame you are always stationary so you notice no change in your fuel, but even if you did the energy content isn't based on mass anyway, it is based on chemistry.
 
An object traveling at high velocity does NOT have an increased mass. The aspect of Relativistic mass is very misleading. A simple way to understand it is that if you were traveling 99% the speed of light, you would not even know it without comparing your frame to another frame of reference. If MASS increased, you would know how fast you were going compared to an "absolute" frame to judge from. This does not happen.
 
If we have an object initially at rest (and use that as our reference frame) and then if the object is accelerated, it would begin to require more and more energy to accelerate it by the same amount as it got closer to the speed of light. Which is why we say the relativistic mass of the object will increase.
frdk91 had the thought that maybe the energy of the moving object could be harnessed and used to further increase its velocity. But when you try to make use of the energy of the moving object, you must slow it down. So you'd simply be slowing the object down, and speeding it up again by the same amount.
 

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