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Site map of:

    Special Relativity

        SR Begin        E=mc2 –notning

        SR End

         SR Model

         NM from SR

         Enegy & Mass

        NM SR diagram

         SR Time

         SR Rest Mass

     Rest Mass Energy will be derived from the Special Relativity (SRT) Interval equation and its significance examined.

     Both Newtonian Mechanics (NM) and SRT are derivable from the same Interval equation, namely

2 + I2 = H2

where     is the distance an object has moved away from  x=0  during the time   and  I is the distance the perpendicular portion of a light beam moved away from  x=0  during the time  t at speed  c  , the speed of light, i.e.,  I=ct  .   H2 is simply the sum of those squares and  H is the distance between the location of that light beam and the object after the time  t  .   If the light beam moved ‘vertically’ the distance  I  , then from the object’s point of view the light beam moved not only vertically but also horizontally and after time  t is now the distance  H away.  Since  H>I  , NM says  H/t is greater than  (I/t)=c so  H/t>c  , call it  c´  .   Therefore,

H=c´t     .  

SRT says light always travels at speed  c so, since  H>I  , then  H is made into


which is where the ‘dilated’ time of SRT originates.  All equations and concepts of SRT follow from this change of  c´t to  ct´  .

     Other equations that will be needed are

γ = ct´/I = c´t/I;    v = x´/t;    u = x´/t´;    v = γu;    P = mγu = mv;    (v/c)2 = γ21

I2 = (ct)2 – x2  = (ct´ )2 – x´ 2  = (ct´´ )2 – x´´ 2  = … ;     I = ct when x=0

where  γ  is the gamma function,  v is NM speed,  u is SRT speed,  P  is momentum, and  m is mass.  The  v and  u never have the same value.  The correctness of these equations has been established elsewhere.

     So the Interval equations for SRT and  NM are:

     Although ‘rest mass energy’, as shown above, “exists” in both SRT and NM, is it ever considered in NM?  Perhaps the concept should be

     Perhaps someone should have finished their algebra.  So-called Rest Mass Energy seems to be the result of not recognizing that as velocity,  u  or  v , approaches 0,  γ  approaches 1.0 which must be ‘corrected’ so that when  u or v is zero,  P  will also equal zero.

On the Strange Concept of Rest Mass Energy

Dr. Sherwood Kaip

1305 Cessna Dr.

El Paso, TX 79925

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2 + I2 = (ct´ )2 ;    (ct´ )2 – x´2 = I2

Multiply both sides by (mc/t)2.

(mc2t´/t)2 (mcx´/t)2 = (mcI/t)2

(γmc2)2(mcx´/t)2 = (mcct/t)2

(γmc2)2(Pc)2 = (mc2)2

E2(Pc)2 = (mc2)2 = (E0)2

(mc2) = (E0)2 is SRT rest mass energy


2 + I2 = (c´t)2 ;    (c´t)2 – x´2 = I2

Multiply both sides by (mc2/ct)2.

(mc2c´t/ct)2(mc2x´/ct)2 = (mc2I/ct)2

(γmc2)2(mcx´/t)2 = (mc2ct/ct)2

(γmc2)2(Pc)2 = (mc2)2

(mc2) could also be considered NM ‘rest mass energy’ but makes no sense.


(Pc)2 = (γmc2)2(mc2)2

(P/c)2 = γ2m2 – m2

(P/c)2 = m2 (γ21)

(P/c)2 = m2 (v/c)2

(P/c) = m (v/c) ;    P = m v = mγu


(Pc)2 = (γmc2)2(mc2)2

(P/c)2 = γ2m2 – m2

(P/c)2 = m2 (γ21)

(P/c)2 = m2 (v/c)2

(P/c) = m (v/c) ;    P = m v