Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > sci.physics.relativity > #430132 > unrolled thread

Talking Nonsense in Einstein's Schizophrenic World

Back to article view | Back to sci.physics.relativity

Contents

  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

Page 1 of 2  [1] 2  Next page →

#430132 — Talking Nonsense in Einstein's Schizophrenic World

Maximum nonsense (this Bingo is one of the silliest Einsteinians):

Max Tegmark - Events and the Nature of Time  https://www.youtube.com/watch?v=rXJBbreLspA

Again nonsense but here Bingo the Einsteiniano admits that spacetime (the absurd consequence of Einstein's false constant-speed-of-light postulate) is incompatible with the Newtonian time of quantum mechanics:

Sean Carroll - Events and the Nature of Time  https://www.youtube.com/watch?v=MhSUSvYdyzA&t=160s

Again nonsense but Bingo the Einsteiniano defines gravitational time dilation (an idiocy devised by Einstein in 1911 that is easy to disprove):

Carlo Rovelli - Events and the Nature of Time  https://www.youtube.com/watch?v=1RJ4t7Ji55k

In their early education Einsteinians are told various idiocies, repeatedly, until in the end they become indistinguishable from Bingo the Clowno:

https://www.youtube.com/watch?v=gX5ajyPr96M 
 Bingo the Clowno

Here is a clear example of the conversion of normal people into thoughtless Bingos: Initially Joe Wolfe's students are sure that the speed of light cannot be the same for differently moving observers but in the end all of them get the name Bingo the Einsteiniano: 

http://www.phys.unsw.edu.au/einsteinlight/jw/module3_weird_logic.htm 
 Joe Wolfe: "At this stage, many of my students say things like "The invariance of the speed of light among observers is impossible" or "I can't understand it". Well, it's not impossible. It's even more than possible, it is true. This is something that has been extensively measured, and many refinements to the Michelson and Morley experiment, and complementary experiments have confirmed this invariance to very great precision. As to understanding it, there isn't really much to understand. However surprising and weird it may be, it is the case. It's the law in our universe. The fact of the invariance of c doesn't take much understanding." 

Pentcho Valev

[toc] | [next] | [standalone]

#430136

Pentcho Valev wrote:

>  Joe Wolfe: "As to understanding it, there isn't really much to
>  understand. However surprising and weird it may be, it is the case.
>  It's the law in our universe. The fact of the invariance of c doesn't
>  take much understanding."

aahaha, "extensively measured"?? What extensively, when they are admitting 
in plain sight, that constancy is just an ASSUMPTION. Just read the above. 
Until an UNDERSTANDING takes place, that thing remains an ASSUMPTION. Or 
an ASSERTION, since you insist. Great post, Dr. Pentcho. Making things 
CLEAR, for me in the first place.

[toc] | [prev] | [next] | [standalone]

#430162

One of the most idiotic assertions in Einstein's schizophrenic world (only the silliest Einsteinians teach it):

Traveling faster than light implies traveling backward in time.

Lisa Randall: "Travel at faster than the speed of light certainly can have dramatic implications that are difficult to understand, such as time travel."  http://www.huffingtonpost.com/lisa-randall/cern-speed-of-light-einstein_b_979883.html

Matt O'Dowd: "Traveling faster than light and traveling backward in time are the same thing."  https://www.youtube.com/watch?v=HUMGc8hEkpc

This is indeed a "monumental shift", a dramatic and irreversible departure from sanity, and here is the relevant hymn sung by the silliest Einsteinians:

Lisa Randall, Michio Kaku, Brian Cox, Neil deGrasse Tyson, Brian Greene: "Now, listen carefully. The faster you move, the heavier you get. Light travels at the same speed no matter how you look at it. No matter how I move relative to you light travels at the same speed. No matter who is doing the measurement and no matter what direction you are moving the speed of light is the same. The speed of light is the same no matter what direction or how fast... As you travel faster time slows down. Everything slows down. Everything slows down. Time slows down when you move. Time passes at a different rate. Clocks run slow. It's a monumental shift in how we see the world. It's a beautiful piece of science. It's a beautifully elegant theory. It's a beautiful piece of science. It's a beautiful piece..."  https://www.youtube.com/watch?v=BuxFXHircaI

Pentcho Valev

[toc] | [prev] | [next] | [standalone]

#430217

Bingo the Einsteiniano brainwashes his students:

Joe Wolfe: "At this stage, many of my students say things like "The invariance of the speed of light among observers is impossible" or "I can't understand it". Well, it's not impossible. It's even more than possible, it is true. This is something that has been extensively measured, and many refinements to the Michelson and Morley experiment, and complementary experiments have confirmed this invariance to very great precision. As to understanding it, there isn't really much to understand. However surprising and weird it may be, it is the case. It's the law in our universe. The fact of the invariance of c doesn't take much understanding."  http://www.phys.unsw.edu.au/einsteinlight/jw/module3_weird_logic.htm

The Michelson-Morley experiment has NOT confirmed the invariance - Bingo is lying about that - but this is a universal lie in Einstein's schizophrenic world (repeated so many times that it is now an absolute truth).

Are students correct in saying that

"The invariance of the speed of light among observers is impossible"?

Of course they are correct. If a light source regularly emits pulses and if the (initially stationary) observer starts moving towards the source, the pulses start hitting the observer MORE FREQUENTLY. For any sane person (students are still sane when they meet Joe Wolfe for the first time) this means that the speed of the pulses relative to the observer HAS INCREASED:

http://www.youtube.com/watch?v=bg7O4rtlwEE 
"Doppler effect - when an observer moves towards a stationary source. ...the velocity of the wave relative to the observer is faster than that when it is still." 

http://www.youtube.com/watch?v=SC0Q6-xt-Xs 
"Doppler effect - when an observer moves away from a stationary source. ...the velocity of the wave relative to the observer is slower than that when it is still." 

Pentcho Valev

[toc] | [prev] | [next] | [standalone]

#430227 — Re: Talking Nonsense in Pentcho's Schizophrenic World

On Monday, August 28, 2017 at 1:55:07 AM UTC-6, Pentcho Valev wrote:
>
> [Irrelevant ranting deleted]
>
> If a light source regularly emits pulses and if the (initially stationary)
> observer starts moving towards the source, the pulses start hitting the
> observer MORE FREQUENTLY. For any sane person (students are still sane
> when they meet Joe Wolfe for the first time) this means that the speed of
> the pulses relative to the observer HAS INCREASED:

Not necessarily.  Pestilent Pentcho, as usual, refuses to consider the
alternate possibility.  Pulses hitting the observer more frequently could
be either the propagation speed of the pulses increasing and the distance
between the pulses remaining constant (the invariant wavelength nonsense)
OR the propagation velocity remaining constant a the distance between the
pulses decreasing.

We have an example of the latter in either theory: an emitter moving wrt
the medium emits pulses that are closer together.  This is also true of
sound waves.  Ignoring this possibility is either ignorance, stupidity
or dishonesty.

[toc] | [prev] | [next] | [standalone]

#430228

On Monday, August 28, 2017 at 1:25:07 PM UTC+5:30, Pentcho Valev wrote:
> Bingo the Einsteiniano brainwashes his students:
> 
> Joe Wolfe: "At this stage, many of my students say things like "The invariance of the speed of light among observers is impossible" or "I can't understand it". Well, it's not impossible. It's even more than possible, it is true. This is something that has been extensively measured, and many refinements to the Michelson and Morley experiment, and complementary experiments have confirmed this invariance to very great precision. As to understanding it, there isn't really much to understand. However surprising and weird it may be, it is the case. It's the law in our universe. The fact of the invariance of c doesn't take much understanding."  http://www.phys.unsw.edu.au/einsteinlight/jw/module3_weird_logic.htm
> 
> The Michelson-Morley experiment has NOT confirmed the invariance - Bingo is lying about that - but this is a universal lie in Einstein's schizophrenic world (repeated so many times that it is now an absolute truth).
> 
> Are students correct in saying that
> 
> "The invariance of the speed of light among observers is impossible"?
> 
> Of course they are correct. If a light source regularly emits pulses and if the (initially stationary) observer starts moving towards the source, the pulses start hitting the observer MORE FREQUENTLY. For any sane person (students are still sane when they meet Joe Wolfe for the first time) this means that the speed of the pulses relative to the observer HAS INCREASED:
> 
> http://www.youtube.com/watch?v=bg7O4rtlwEE 
> "Doppler effect - when an observer moves towards a stationary source. ...the velocity of the wave relative to the observer is faster than that when it is still." 
> 
> http://www.youtube.com/watch?v=SC0Q6-xt-Xs 
> "Doppler effect - when an observer moves away from a stationary source. ...the velocity of the wave relative to the observer is slower than that when it is still." 
> 
> Pentcho Valev

Interesting.  Suppose a source were to emit microsecond wave pulses instead of a continuous stream of light, these short pulses would be moving faster towards the observer.  Would the Doppler shift occur?

[toc] | [prev] | [next] | [standalone]

#430229

On Sunday, August 27, 2017 at 9:45:59 PM UTC+5:30, Pentcho Valev wrote:
> One of the most idiotic assertions in Einstein's schizophrenic world (only the silliest Einsteinians teach it):
> 
> Traveling faster than light implies traveling backward in time.
> 
> Lisa Randall: "Travel at faster than the speed of light certainly can have dramatic implications that are difficult to understand, such as time travel."  http://www.huffingtonpost.com/lisa-randall/cern-speed-of-light-einstein_b_979883.html
> 
> Matt O'Dowd: "Traveling faster than light and traveling backward in time are the same thing."  https://www.youtube.com/watch?v=HUMGc8hEkpc
> 
> This is indeed a "monumental shift", a dramatic and irreversible departure from sanity, and here is the relevant hymn sung by the silliest Einsteinians:
> 
> Lisa Randall, Michio Kaku, Brian Cox, Neil deGrasse Tyson, Brian Greene: "Now, listen carefully. The faster you move, the heavier you get. Light travels at the same speed no matter how you look at it. No matter how I move relative to you light travels at the same speed. No matter who is doing the measurement and no matter what direction you are moving the speed of light is the same. The speed of light is the same no matter what direction or how fast... As you travel faster time slows down. Everything slows down. Everything slows down. Time slows down when you move. Time passes at a different rate. Clocks run slow. It's a monumental shift in how we see the world. It's a beautiful piece of science. It's a beautifully elegant theory. It's a beautiful piece of science. It's a beautiful piece..."  https://www.youtube.com/watch?v=BuxFXHircaI
> 
> Pentcho Valev

"Now, listen carefully. The faster you move, the heavier you get"

Relative to what? How can you move faster compared to empty space which is nothingness? 

[toc] | [prev] | [next] | [standalone]

#430233

On Monday, August 28, 2017 at 4:27:23 AM UTC-6, gehan.am...@gmail.com wrote:
>
> On Sunday, August 27, 2017 at 9:45:59 PM UTC+5:30, Pentcho Valev quote:
> >
> > Lisa Randall, Michio Kaku, Brian Cox, Neil deGrasse Tyson, Brian
> > Greene: "Now, listen carefully. The faster you move, the heavier you get.
>
> "Now, listen carefully. The faster you move, the heavier you get"
> 
> Relative to what?

This is shortcut talk.  The faster an object moves (relative to an observer),
the more kinetic energy (relative to the observer), right?  By E = mc^2, or
m = E/c^2, the more mass the object appears to have.

> How can you move faster compared to empty space which is nothingness?

Empty space is not nothingness.  For one thing, it contains vacuum energy.

[toc] | [prev] | [next] | [standalone]

#430650

On Monday, August 28, 2017 at 5:13:14 PM UTC+5:30, Gary Harnagel wrote:
> On Monday, August 28, 2017 at 4:27:23 AM UTC-6, gehan.am...@gmail.com wrote:
> >
> > On Sunday, August 27, 2017 at 9:45:59 PM UTC+5:30, Pentcho Valev quote:
> > >
> > > Lisa Randall, Michio Kaku, Brian Cox, Neil deGrasse Tyson, Brian
> > > Greene: "Now, listen carefully. The faster you move, the heavier you get.
> >
> > "Now, listen carefully. The faster you move, the heavier you get"
> > 
> > Relative to what?
> 
> This is shortcut talk.  The faster an object moves (relative to an observer),
> the more kinetic energy (relative to the observer), right?  By E = mc^2, or
> m = E/c^2, the more mass the object appears to have.
> 
> > How can you move faster compared to empty space which is nothingness?
> 
> Empty space is not nothingness.  For one thing, it contains vacuum energy.

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  ?

[toc] | [prev] | [next] | [standalone]

#430705

On Friday, September 1, 2017 at 4:45:01 AM UTC-6, gehan.am...@gmail.com wrote:
>
> On Monday, August 28, 2017 at 5:13:14 PM UTC+5:30, Gary Harnagel wrote:
> >
> > On Monday, August 28, 2017 at 4:27:23 AM UTC-6, gehan.am...@gmail.com wrote:
> > >
> > > "Now, listen carefully. The faster you move, the heavier you get"
> > > 
> > > Relative to what?
> > 
> > This is shortcut talk.  The faster an object moves (relative to an
> > observer), the more kinetic energy (relative to the observer), right?
> >  By E = mc^2, or m = E/c^2, the more mass the object appears to have.
> > 
> > > How can you move faster compared to empty space which is nothingness?
> > 
> > Empty space is not nothingness.  For one thing, it contains vacuum energy.
> 
> So the maximum Kinetic Energy an object can have relative to any observer
> is 1/2 mv^2

That's an approximation derived from Newtonian physics.

> and where v=c, then 1/2 mc^2  ?

Incorrect.

"Vacuum energy 
Vacuum energy is an underlying background energy that exists in space throughout the entire Universe. One contribution to the vacuum energy may be from virtual particles which are thought to be particle pairs that blink into existence and then annihilate in a timespan too short to observe. They are expected to do this everywhere, throughout the Universe." 

> -Wikipedia 
> 
> "may be from virtual particles..." sounds like fairy tales to me.

If it sounds like fairy tales to you, then you are stuck in the dead past
like that abysmally-stupid Led Natham.

[toc] | [prev] | [next] | [standalone]

#430726

On 9/1/17 5:44 AM, gehan.ameresekere@gmail.com wrote:
> On Monday, August 28, 2017 at 5:13:14 PM UTC+5:30, Gary Harnagel wrote:
>> On Monday, August 28, 2017 at 4:27:23 AM UTC-6, gehan.am...@gmail.com wrote:
>>>
>>> On Sunday, August 27, 2017 at 9:45:59 PM UTC+5:30, Pentcho Valev quote:
>>>>
>>>> Lisa Randall, Michio Kaku, Brian Cox, Neil deGrasse Tyson, Brian
>>>> Greene: "Now, listen carefully. The faster you move, the heavier you get.
>>>
>>> "Now, listen carefully. The faster you move, the heavier you get"
>>>
>>> Relative to what?
>>
>> This is shortcut talk.  The faster an object moves (relative to an observer),
>> the more kinetic energy (relative to the observer), right?  By E = mc^2, or
>> m = E/c^2, the more mass the object appears to have.
>>
>>> How can you move faster compared to empty space which is nothingness?
>>
>> Empty space is not nothingness.  For one thing, it contains vacuum energy.
> 
> 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  ?
> 
> 

1/2mv^2 is not the correct expression for kinetic energy, though it's a 
handy approximation to use in everyday cases.

-- 
Odd Bodkin -- maker of fine toys, tools, tables

[toc] | [prev] | [next] | [standalone]

#430856 — Mass and kinetic energy (was: Talking Nonsense in Einstein's Schizophrenic World)

gehan.ameresekere@gmail.com wrote:
^^^^^^^^^^^^^^^^^^^^^^^^^^^
“Internet is the thing with cables; Usenet is the thing with *people*.”  
Your *real* *name* belongs there.  Subscribe to the newsgroup
or (better) use a proper newsreader to make that possible.

> On Monday, August 28, 2017 at 5:13:14 PM UTC+5:30, Gary Harnagel wrote:
>> On Monday, August 28, 2017 at 4:27:23 AM UTC-6, gehan.am...@gmail.com
>> wrote:
>> > On Sunday, August 27, 2017 at 9:45:59 PM UTC+5:30, Pentcho Valev quote:
>> > > Lisa Randall, Michio Kaku, Brian Cox, Neil deGrasse Tyson, Brian
>> > > Greene: "Now, listen carefully. The faster you move, the heavier you
>> > > get.
>> > "Now, listen carefully. The faster you move, the heavier you get"
>> > Relative to what?
>> 
>> This is shortcut talk.

ACK.

>> The faster an object moves (relative to an observer),
>> the more kinetic energy (relative to the observer), right? 

Correct.

>> 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.  E = m c² is the *wrong* equation if E 
is to be the kinetic energy or the total energy of a massive object and m is 
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”.  The latter two are ill-conceived, 
outdated concepts introduced by people other than Einstein – even explicitly 
condemned by Einstein –, 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.
 
>> > 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.  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*).
 
> 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  ?

No (see also my other follow-up).  The kinetic energy is

  Eₖ = m c² (γ − 1)

with the Lorentz factor

  γ = 1∕√(1 − v²∕c²)

instead (in this notation you can most easily see that at relative rest, 
where v = 0 → γ = 1, the kinetic energy of a massive object is zero, as
it should be).

It turns out that

  Eₖ_{Newton} = 1∕2 m v²

is only a first-order approximation that only works for motion of an object 
with a relative speed that is much less than the speed of light (v ≪ c; 
which is why AFAIK nobody doubted it until Einstein posited special 
relativity).

In special relativity, the total energy E of a massive object can be derived 
from the norm of its 4-momentum:

   P⃗    = (E∕c, p⃗)

 ||P⃗||² = −(E∕c)² + p² = −(m c)²
          E²           = m² c⁴ + p² c²           Energy–momentum relation
          E            = √((m c²)² + (p c)²)
          E            = √((m c²)² + (γ m v c)²).

where P⃗ is the 4-momentum, and p⃗ is the 3-momentum.

Expanding γ as defined above, this can be written as

   E = γ m c².
     = m c²∕√(1 − v²∕c²),

(left as an exercise to the reader) and one can clearly see that the total 
energy at relative rest (rest energy; at v = 0) is

  E₀ = m c²

(as derived by Einstein before he found the energy–momentum relation, from 
Maxwell’s equations, in “Does the Inertia of a Body Depend upon its Energy 
Content?” [1905]).  [One can also see it immediately by setting p = γ m v
= 0 as v = 0 in the energy–momentum relation above.]

Why is this relevant?  Because the total energy of *any* object at *any* 
relative speed must be the sum of its *rest energy* and its kinetic energy:

  E   = E₀ + Eₖ.

So the kinetic energy for a massive object is

  Eₖ  = E      − E₀
      = γ m c² − m c².

Writing this as

  Eₖ  = 1∕√(1 − v²∕c²) m c² − m c²
      = (1 − v²∕c²)^(−1∕2) m c² − m c²

one can use binomial approximation (I learned it as “binomial expansion”) to 
see that the classical kinetic energy is *a good approximation* *only* as 
long as v ≪ c, i.e. v²∕c² ≪ 1:

  (1 ± x)^a ≈ 1 ± a x  where x ≪ 1,

so

  Eₖ = (1 − v²∕c²)^(−1∕2) m c² − m c²
     ≈ (1 + 1∕2 v²∕c²) m c²    − m c²
     = m c² + 1∕2 m v²         − m c²

  Eₖ ≈ 1∕2 m v² = Eₖ_{Newton}. ∎

<https://en.wikipedia.org/wiki/Kinetic_energy#Relativistic_kinetic_energy_of_rigid_bodies>

-- 
PointedEars

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

[toc] | [prev] | [next] | [standalone]

#430864 — Re: Mass and kinetic energy (was: Talking Nonsense in Einstein's Schizophrenic World)

On Saturday, September 2, 2017 at 4:04:33 PM UTC-6, Thomas 'PointedEars' Lahn wrote:
>
> gehan.ameresekere@gmail.com wrote:
> ^^^^^^^^^^^^^^^^^^^^^^^^^^^
> “Internet is the thing with cables; Usenet is the thing with *people*.”  
> Your *real* *name* belongs there.  Subscribe to the newsgroup
> or (better) use a proper newsreader to make that possible.
> 
> > On Monday, August 28, 2017 at 5:13:14 PM UTC+5:30, Gary Harnagel wrote:
> > >
> > > On Monday, August 28, 2017 at 4:27:23 AM UTC-6, gehan.am...@gmail.com
> > > wrote:
> > > > "Now, listen carefully. The faster you move, the heavier you get"
> > > > Relative to what?
> > > 
> > > This is shortcut talk.
> 
> ACK.
> 
> >> The faster an object moves (relative to an observer),
> >> the more kinetic energy (relative to the observer), right? 
> 
> Correct.
> 
> > > 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.

> E = m c² is the *wrong* equation if E is to be the kinetic energy

Obviously.

> 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.

> 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.

> The latter two are ill-conceived, outdated concepts introduced by people
> other than Einstein

As I understand it, he introduced it originally.

> – even explicitly condemned by Einstein

Later.

> –, 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

> > > > 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. 

> 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.

> > 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.

Posturing follows:

> No (see also my other follow-up).  The kinetic energy is
> 
>   Eₖ = m c² (γ − 1)
> 
> with the Lorentz factor
> 
>   γ = 1∕√(1 − v²∕c²)
> 
> instead (in this notation you can most easily see that at relative rest, 
> where v = 0 → γ = 1, the kinetic energy of a massive object is zero, as
> it should be).
> 
> It turns out that
> 
>   Eₖ_{Newton} = 1∕2 m v²
> 
> is only a first-order approximation that only works for motion of an object 
> with a relative speed that is much less than the speed of light (v ≪ c; 
> which is why AFAIK nobody doubted it until Einstein posited special 
> relativity).
> 
> In special relativity, the total energy E of a massive object can be derived 
> from the norm of its 4-momentum:
> 
>    P⃗    = (E∕c, p⃗)
> 
>  ||P⃗||² = −(E∕c)² + p² = −(m c)²
>           E²           = m² c⁴ + p² c²           Energy–momentum relation
>           E            = √((m c²)² + (p c)²)
>           E            = √((m c²)² + (γ m v c)²).
> 
> where P⃗ is the 4-momentum, and p⃗ is the 3-momentum.
> 
> Expanding γ as defined above, this can be written as
> 
>    E = γ m c².
>      = m c²∕√(1 − v²∕c²),
> 
> (left as an exercise to the reader) and one can clearly see that the total 
> energy at relative rest (rest energy; at v = 0) is
> 
>   E₀ = m c²
> 
> (as derived by Einstein before he found the energy–momentum relation, from 
> Maxwell’s equations, in “Does the Inertia of a Body Depend upon its Energy 
> Content?” [1905]).  [One can also see it immediately by setting p = γ m v
> = 0 as v = 0 in the energy–momentum relation above.]
> 
> Why is this relevant?  Because the total energy of *any* object at *any* 
> relative speed must be the sum of its *rest energy* and its kinetic energy:
> 
>   E   = E₀ + Eₖ.
> 
> So the kinetic energy for a massive object is
> 
>   Eₖ  = E      − E₀
>       = γ m c² − m c².
> 
> Writing this as
> 
>   Eₖ  = 1∕√(1 − v²∕c²) m c² − m c²
>       = (1 − v²∕c²)^(−1∕2) m c² − m c²
> 
> one can use binomial approximation (I learned it as “binomial expansion”) to 
> see that the classical kinetic energy is *a good approximation* *only* as 
> long as v ≪ c, i.e. v²∕c² ≪ 1:
> 
>   (1 ± x)^a ≈ 1 ± a x  where x ≪ 1,
> 
> so
> 
>   Eₖ = (1 − v²∕c²)^(−1∕2) m c² − m c²
>      ≈ (1 + 1∕2 v²∕c²) m c²    − m c²
>      = m c² + 1∕2 m v²         − m c²
> 
>   Eₖ ≈ 1∕2 m v² = Eₖ_{Newton}. ∎
> 
> <https://en.wikipedia.org/wiki/Kinetic_energy#Relativistic_kinetic_energy_of_rigid_bodies>
> 
> -- 
> PointedEars
> 
> Twitter: @PointedEars2
> Please do not cc me. / Bitte keine Kopien per E-Mail.

[toc] | [prev] | [next] | [standalone]

#430870 — Re: Mass and kinetic energy

</killfile>

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.

[toc] | [prev] | [next] | [standalone]

#430873 — Re: Mass and kinetic energy

On Saturday, September 2, 2017 at 6:11:26 PM UTC-6, Thomas 'PointedEars' Lahn wrote:
>
> </killfile>

Beat you to it, deranged one.

> 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.

[toc] | [prev] | [next] | [standalone]

#430961 — Re: Mass and kinetic energy

</killfile>

Gary Harnagel wrote:

> On Saturday, September 2, 2017 at 6:11:26 PM UTC-6, Thomas 'PointedEars'
> Lahn wrote:
>> </killfile>
> 
> Beat you to it, deranged one.

Now I am curious.  IIUC, ”I beat you to it” means “I was faster than you”.

So:

Did you modify my Google Groups spam filter userscript[1] to work as a 
killfile?

Did you find another working script or browser extension that establishes
a killfile for Google Groups?

If none of the above, you must be lying.

> [Full quote of 100+ lines]

Good grief.

<killfile>

_______
[1] <https://github.com/PointedEars/userscripts/>
-- 
PointedEars

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

[toc] | [prev] | [next] | [standalone]

#430975 — Re: Mass and kinetic energy

On Sunday, September 3, 2017 at 1:42:18 PM UTC-6, Thomas 'PointedEars' Lahn wrote:
> </killfile>
> 
> Gary Harnagel wrote:
> >
> > On Saturday, September 2, 2017 at 6:11:26 PM UTC-6, Thomas 'PointedEars'
> > Lahn wrote:
> >> </killfile>
> > 
> > Beat you to it, deranged one.
> 
> Now I am curious.  IIUC, ”I beat you to it” means “I was faster than you”.
> 
> So:
> 
> Did you modify my Google Groups spam filter userscript[1] to work as a 
> killfile?
> 
> Did you find another working script or browser extension that establishes
> a killfile for Google Groups?
> 
> If none of the above, you must be lying.
> 
> > [Full quote of 100+ lines]
> 
> Good grief.
> 
> <killfile>
> 
> _______
> [1] <https://github.com/PointedEars/userscripts/>
> -- 
> PointedEars
> 
> Twitter: @PointedEars2
> Please do not cc me. / Bitte keine Kopien per E-Mail.

I can't see your posts because I have made you irrelevant.

Good grief!  Have you no sense of humor?  That's a symptom of autism.

Are you autistic?

[toc] | [prev] | [next] | [standalone]

#431053 — Re: Mass and kinetic energy

Gary Harnagel wrote:

>> [1] <https://github.com/PointedEars/userscripts/>
>> --
>> PointedEars
>> 
>> Twitter: @PointedEars2 Please do not cc me. / Bitte keine Kopien per
>> E-Mail.
> 
> I can't see your posts because I have made you irrelevant.
> Good grief!  Have you no sense of humor?  That's a symptom of autism. 
> Are you autistic?

Absolutely, Gigi, valid observation. Pointy is a fruit cake.

[toc] | [prev] | [next] | [standalone]

#431056 — Re: Mass and kinetic energy

Gary Harnagel wrote:

>> [1] <https://github.com/PointedEars/userscripts/>
>> --
>> PointedEars
>> 
>> Twitter: @PointedEars2 Please do not cc me. / Bitte keine Kopien per
>> E-Mail.
> 
> I can't see your posts because I have made you irrelevant. 
> Good grief!  Have you no sense of humor?  That's a symptom of autism.
> Are you autistic?

He is plonking a lot of woman around here, I can see. For whatever obscure 
reason.

[toc] | [prev] | [next] | [standalone]

#431137 — Re: Mass and kinetic energy

The ’nym-shifting troll trolled as "Ethel Ocallaghan" <unlgclo@awlwaac.ag>:

> He is plonking a lot of woman around here, I can see. For whatever obscure
> reason.

You are neither a woman nor a man, or anything in-between.  You might not 
even be a human being.  You are a pretender, a gibbering troll, using a 
troll-friendly news server with a fake sender, who changes their pseudonym 
the moment one is exposed.  As I am expecting now.

*PLONK* & F’up2 where it belongs

-- 
PointedEars

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

[toc] | [prev] | [next] | [standalone]

Page 1 of 2  [1] 2  Next page →

Back to top | Article view | sci.physics.relativity

csiph-web