What Are the Algebraic Mysteries in Energy-Momentum-Mass Relations?

  • Thread starter Thread starter Bazinga101
  • Start date Start date
  • Tags Tags
    Algebra Relations
Bazinga101
Messages
2
Reaction score
0
<<Mentor note: Please always use descriptive thread titles.>>

First of all, the title is such that it attracts most views.You see, in class our professor did some goofing around numbers and variables in the relativistic energy momentum relation:
E2=(pc)2+m02c4
Since the energy required to accelerate an object to a certain velocity is
E=m0c2/√1-v2/c2,
∴E2=m02c4/1-v2/c2
plug in the value of E2,
p2c2+m02c4=m02c4/1-v2/c2
cancel out the m02c4
so p2c2=1/1-v2/c2
since c2= E/m,
⇒Ep2/m=1/1-v2/c2\
But, p2/m = 2* K.E and since E in E=mc2 implies any form of energy,and the object gains kinetic energy through it's motion, so Ek=E
⇒E(2E)=1/1-v2/c2
⇒2E2=1/1-v2/c2
⇒E2=1/2(1-v2/c2)
⇒E2=1/2-v2/c2
⇒E=1/√2-v2/c2
and that's it.No one in the room could figure out what's wrong, but our prof. said that something is wrong, but it is our job to find it out, plus, immediately one notices that if v=c, E=1 J. WTH!
 
Last edited by a moderator:
Physics news on Phys.org
This might actually be readable if you put in some parentheses.
 
Bazinga101 said:
p2c2+m02c4=m02c4/1-v2/c2
cancel out the m02c4
so p2c2=1/1-v2/c2
That's... an interesting piece of algebra you did there.
 
Bandersnatch said:
That's... an interesting piece of algebra you did there.
Thanks Bandersnatch, i finally find out the mistake he did, and sorry for sounding stupid
 
In Philippe G. Ciarlet's book 'An introduction to differential geometry', He gives the integrability conditions of the differential equations like this: $$ \partial_{i} F_{lj}=L^p_{ij} F_{lp},\,\,\,F_{ij}(x_0)=F^0_{ij}. $$ The integrability conditions for the existence of a global solution ##F_{lj}## is: $$ R^i_{jkl}\equiv\partial_k L^i_{jl}-\partial_l L^i_{jk}+L^h_{jl} L^i_{hk}-L^h_{jk} L^i_{hl}=0 $$ Then from the equation: $$\nabla_b e_a= \Gamma^c_{ab} e_c$$ Using cartesian basis ## e_I...
Insights auto threads is broken atm, so I'm manually creating these for new Insight articles. The Relativator was sold by (as printed) Atomic Laboratories, Inc. 3086 Claremont Ave, Berkeley 5, California , which seems to be a division of Cenco Instruments (Central Scientific Company)... Source: https://www.physicsforums.com/insights/relativator-circular-slide-rule-simulated-with-desmos/ by @robphy
Abstract The gravitational-wave signal GW250114 was observed by the two LIGO detectors with a network matched-filter signal-to-noise ratio of 80. The signal was emitted by the coalescence of two black holes with near-equal masses ## m_1=33.6_{-0.8}^{+1.2} M_{⊙} ## and ## m_2=32.2_{-1. 3}^{+0.8} M_{⊙}##, and small spins ##\chi_{1,2}\leq 0.26 ## (90% credibility) and negligible eccentricity ##e⁢\leq 0.03.## Postmerger data excluding the peak region are consistent with the dominant quadrupolar...
Back
Top