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Re: Mass and kinetic energy

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Gary Harnagel wrote:

> On Saturday, September 2, 2017 at 4:04:33 PM UTC-6, Thomas 'PointedEars'
> Lahn wrote:
>> > > By E = mc^2, or m = E/c^2, the more mass the object appears to have.
>> 
>> (In the following I am using the term “massive object” to mean an object
>> whose mass is greater than zero.)
>> 
>> No, this is a common misconception.
> 
> Wrong.

No, it *is* wrong and it *is* a common misconception.
 
>> E = m c² is the *wrong* equation if E is to be the kinetic energy
> 
> Obviously.

At least you managed to understand that.
 
>> or the total energy of a massive object and m is the object’s mass.
> 
> E is the total energy of a massive object at rest.

But *only at (relative) rest*, and that is the point.  The object that you 
describe is _not_ at (relative) rest, so m is _not_ the object’s mass.
 
>> It is only correct if E *either* is the *rest* energy, *or* m is the so-
>> called “relativistic mass”: either E₀ = m c²; or E = m_{rel} c² with
>> m_{rel} = γ m₀, where m₀ is the “rest mass”.
> 
> Obviously.

Obviously not obvious to you as you have claimed something that contradicts 
this.
 
>> The latter two are ill-conceived, outdated concepts introduced by people
>> other than Einstein
> 
> As I understand it, he introduced it originally.

You misunderstand.

>> – even explicitly condemned by Einstein
> 
> Later.

When he learned of it.

>> –, and (as we can see here) potentially confusing to
>> students; however, some scientists, like Michio Kaku from whom the sound
>> bite is, are still willing to employ them – in popular-scientific talk at
>> least.
>> 
>> In modern physics, there is only (rest) mass (m = m₀).  It is Lorentz-
>> *invariant* (it is *the same* for all observers, no matter their motion
>> relative to the object) – as the Minkowski norm squared of the
>> four-momentum is (*always*)
>> 
>>   ||P||² = −m² c²
>> 
>> (see below), and c is the isotropic speed of light –, and so is rest
>> energy, but *kinetic* energy is not.
> 
> Total energy is gamma*m*c^2

First of all, your statement does not contradict mine; rather the contrary.

Second, I said the same in the part that you did not read or understand,
but derided.
 
>> > > > How can you move faster compared to empty space which is
>> > > > nothingness?
>> > > Empty space is not nothingness.  For one thing, it contains vacuum
>> > > energy.
>> True, but irrelevant.
> 
> Gehan claimed that space it nothingness.  This is dead wrong, so you have
> become irrelevant to the discussion.

Your *wrong* statement is irrelevant.  Empty space *has* energy, it does 
_not_ contain it.  And the particle pairs created are just virtual, so they 
cannot serve for a proper frame of reference.

You are just regurgitating what you misunderstood from scanning the Web,
if that.
 
>> The correct, simpler explanation (that does not require either the
>> theories of relativity nor quantum mechanics) is that velocity is
>> *defined* as the change of position per unit time – v⃗ = ∂x⃗∕∂t –, and
>> a frame of reference is required in order to define positions and times. 
>> So speed, the magnitude of velocity, is *also* always *only* defined
>> relative to something else (e.g., if you are sitting in a train that is
>> moving relative to the ground, the speed of the train relative *to you*
>> is *zero*).
> 
> Irrelevant.

Not at all.  Space can be empty and velocity/speed can *still* be measured, 
because velocity/speed is a matter of *definition*.
 
>> > So the maximum Kinetic Energy an object can have relative to any
>> > observer is 1/2 mv^2 and where v=c, then 1/2 mc^2  ?
> 
> Provide proper formatting.  I didn't write that.

So you are not able to count either.
 
> Posturing follows: […]

If only you had read it and attempted to understand it instead of deriding 
it, you might have managed to learn something.

<killfile>

-- 
PointedEars

Twitter: @PointedEars2
Please do not cc me. / Bitte keine Kopien per E-Mail.

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Thread

Talking Nonsense in Einstein's Schizophrenic World Pentcho Valev <pvalev@yahoo.com> - 2017-08-27 01:18 -0700
  Re: Talking Nonsense in Einstein's Schizophrenic World Bídníkùm Laterá <bila@wehia.ui> - 2017-08-27 09:52 +0000
  Re: Talking Nonsense in Einstein's Schizophrenic World Pentcho Valev <pvalev@yahoo.com> - 2017-08-27 09:15 -0700
    Re: Talking Nonsense in Einstein's Schizophrenic World Pentcho Valev <pvalev@yahoo.com> - 2017-08-28 00:55 -0700
      Re: Talking Nonsense in Pentcho's Schizophrenic World Gary Harnagel <hitlong@yahoo.com> - 2017-08-28 03:22 -0700
      Re: Talking Nonsense in Einstein's Schizophrenic World gehan.ameresekere@gmail.com - 2017-08-28 03:23 -0700
    Re: Talking Nonsense in Einstein's Schizophrenic World gehan.ameresekere@gmail.com - 2017-08-28 03:27 -0700
      Re: Talking Nonsense in Einstein's Schizophrenic World Gary Harnagel <hitlong@yahoo.com> - 2017-08-28 04:43 -0700
        Re: Talking Nonsense in Einstein's Schizophrenic World gehan.ameresekere@gmail.com - 2017-09-01 03:44 -0700
          Re: Talking Nonsense in Einstein's Schizophrenic World Gary Harnagel <hitlong@yahoo.com> - 2017-09-01 12:07 -0700
          Re: Talking Nonsense in Einstein's Schizophrenic World Odd Bodkin <bodkinodd@gmail.com> - 2017-09-01 14:53 -0500
          Mass and kinetic energy (was: Talking Nonsense in Einstein's Schizophrenic World) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-03 00:04 +0200
            Re: Mass and kinetic energy (was: Talking Nonsense in Einstein's Schizophrenic World) Gary Harnagel <hitlong@yahoo.com> - 2017-09-02 16:28 -0700
              Re: Mass and kinetic energy Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-03 02:11 +0200
                Re: Mass and kinetic energy Gary Harnagel <hitlong@yahoo.com> - 2017-09-02 17:29 -0700
                Re: Mass and kinetic energy Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-03 21:42 +0200
                Re: Mass and kinetic energy Gary Harnagel <hitlong@yahoo.com> - 2017-09-03 15:48 -0700
                Re: Mass and kinetic energy Ethel Ocallaghan <unlgclo@awlwaac.ag> - 2017-09-04 16:38 +0000
                Re: Mass and kinetic energy Ethel Ocallaghan <unlgclo@awlwaac.ag> - 2017-09-04 16:44 +0000
                Re: Mass and kinetic energy Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-05 08:37 +0200
                Re: Mass and kinetic energy Istrátora Metiku <untw@nwpovu.un> - 2017-09-06 12:58 +0000
            Mass–speed relation (was: Mass and kinetic energy) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-09 21:51 +0200
              Re: Mass–speed relation (was: Mass and kinetic energy) Utorských Vitelé <hue@svwor.hh> - 2017-09-09 21:12 +0000
        Re: Talking Nonsense in Einstein's Schizophrenic World gehan.ameresekere@gmail.com - 2017-09-01 03:46 -0700
          Re: Talking Nonsense in Einstein's Schizophrenic World Ned Latham <nedlatham@woden.valhalla.oz> - 2017-09-01 06:02 -0500
          Vacuum energy (was: Talking Nonsense in Einstein's Schizophrenic World) Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2017-09-03 02:23 +0200
  Re: Talking Nonsense in Einstein's Schizophrenic World Pentcho Valev <pvalev@yahoo.com> - 2017-08-28 09:28 -0700
    Re: Talking Nonsense in Einstein's Schizophrenic World JanPB <filmart@gmail.com> - 2017-08-30 16:40 -0700
  Re: Talking Nonsense in Einstein's Schizophrenic World JanPB <filmart@gmail.com> - 2017-09-02 23:26 -0700

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