Mass is Energy Moving Faster then Light?

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SUMMARY

The discussion centers on the interpretation of energy in the context of special relativity (SR) and general relativity (GR), specifically addressing the formula E = integral(p(v)*dv). Participants critique a video that presents flawed arguments regarding mass and energy, emphasizing that energy should approach infinity as velocity approaches the speed of light (c). The correct interpretation involves the gamma factor, γ, which is defined as 1/sqrt(1-v²/c²). The discussion concludes that the video misrepresents these fundamental concepts.

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  • Understanding of special relativity (SR) and general relativity (GR)
  • Familiarity with the concept of the gamma factor (γ)
  • Knowledge of integral calculus, specifically in the context of physics
  • Basic understanding of energy-mass equivalence (E=mc²)
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  • Study the derivation of the gamma factor in special relativity
  • Explore the implications of energy approaching infinity as velocity approaches the speed of light
  • Learn about the integral calculus applications in physics, particularly in energy calculations
  • Investigate common misconceptions in popular science videos regarding relativity
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Physics students, educators, and anyone interested in the principles of special and general relativity, particularly those seeking to clarify misconceptions about energy and mass in relativistic contexts.

csmcmillion
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Wondering if any of you who are more competent in SR/GR than I am have seen this:



The arguments made in the video seem wrong on so many levels. In response to a comment I made I received this:

E = integral (p(v)*dv) is the most efficient interpretation of Energie. this is the correct interpretation mass appears from negativ acceleration from speed of light Energie depends only on speed relativ to c.

this formula can be simply verified if you take E = Integral ( p(v)*dv) p(v) = v* m*gamma(v) for gamme(v) = 1/sqrt(1-v²/c²).

E= integral( v*m/sqrt/(1-v²/c²))*dv) = [ -m*c²*sqrt(1-v²/c²)] from v0 to v1.

For v0=0 and v1 = c you get E=m*c². For v0 = v and v1 = c you get E² = m²*c4+c²*v²*m² ...for small v1 < c/10 you can see that the result will equal E=v²*m/2


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That video looks like crap. It has just text, still images, and music.
 
E=\gamma mc^2 = \frac{mc^2}{\sqrt{1-\frac{v^2}{c^2}}}

His gamma factor is wrong...

If his gamma factor was correct, then for v approaching c, then the energy approaches 0...whereas the energy should approach infinity.
 

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