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Re: Gravity needs NO Matter

Followups directed to: sci.physics.relativity

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Y.Porat wrote:

> On Monday, February 1, 2016 > --
>> Two neutrinos go through a bar ...
>> 
>> (from: WolframAlpha)

What you are quoting here is a (randomly selected) Usenet signature.  You 
are not referring to it in your follow-up, so you should not have quoted it.  
As you should not quote anything that you are *not* referring to, while you 
should quote *everything* that you *are* referring to, even if you have to 
shorten it.  Simply omitting relevant quotations as you did (and replacing 
them with irrelevant ones) is _not_ appropriate discussion style.

> =====================================
> =======================================

Please don’t.

> you are a common  parrot manipulator !!

I have no idea what that is supposed to mean, but evidentially you are a 
name-caller, and not a very good one at that.
 
> if V= c

That’s _v_ (lowercase letter) in the equation that I have posted (and you 
have not quoted).

> gamma becomes undefined ***even mathematically**!!

The equation in my posting that you are referring to is either the equation 
for the momentum of objects whose mass is *not zero* –

  p = m v∕√(1 − (v∕c)²); m ≠ 0(!)
                         ^^^^^^^^

– or the equation for the kinetic energy of *such* objects –

  E_k = m c²∕√(1 − (v∕c)²) − m c²; m ≠ 0(!)
                                   ^^^^^^^^
    [Why?  You subtract from the total energy that such an object has in
     relative motion the energy that it has *at relative rest*, E = m c².]

–, so *neither applies to photons* as *photons have mass zero* (m = 0) and 
(the magnitude of) their momentum is

  p = ℏ k = ℎ∕λ = ℎ f∕c

instead (where ℏ = ℎ∕2π, k = |k⃗| = 2π∕λ is the wave number, k⃗ is the wave 
vector, λ is the wavelength, and f is the wave’s frequency).  As I have said 
multiple times now (as if it would not be self-evident to all who can read), 
*the velocity v does not feature in the momentum equation for photons*, nor 
does their zero mass.  Why?  Photons *always* travel at c.

However, the energy–momentum relation from special relativity that I 
posted –

  E = √((m c²)² + (p c)²)

– is supposed to apply to *all* physical objects.  It depends only on their 
mass m and on their *object-specific* momentum p (since c is a constant).  
As a function of mass and momentum then, and with explicit multiplication 
sign, you can write it

  E(m, p) = √((m × c²)² + (p × c)²).

Photons have m = 0 and p = ℏ k = ℎ∕λ = ℎ f∕c, so they have energy

  E(0, p) = √(p × c)² = p × c = ℎ f∕c × c = ℎ f

which confirms _Einstein’s_ prior observations and reasoning about the 
photoelectric effect.

What is so difficult for you to understand about that?

> and you  jangler manipulations want help  you!!
> you cant fish in dirty water !!

Gibberish.

> 2
> in that case
> see the formula
> E=hf photon Energy
> it was found  EXPERIMENTALLY 5 YEARS BEFORE RELATIVITY !!!

Can’t you read?  Your claim is *wrong*; it was _Einstein_ who found that 
"formula" “experimentally” _in 1905_, _only three months_ before he 
published the first paper on special relativity.

Planck did find and present in 1900 to the Deutsche Physikalische 
Gesellschaft (German Society of Physics) a radiation law that featured ℎ (of 
which sources that I have not confirmed yet say that was chosen as an 
abbreviation for German „Hilfsgrösse“ [“helper quantity”]), but *nobody*, 
including Planck, was aware of ℎ’s importance for photon energy *at the 
time*.

> Planck didn t use any F

Nobody but you used “F” (capital letter).  I used “f” (lowercase letter) for 
frequency.  Planck used “ν” for frequency, which he called “oscillation 
number (per second)” in “On the Law of Distribution of Energy in the Normal 
Spectrum” (1900/1901), but E = ℎν does not feature either in that work 
(which you can’t have read, let alone understood):

<http://www.physik.uni-augsburg.de/annalen/history/historic-papers/1901_309_553-563.pdf>

> en relativistic entity/TOOL  to define it
> EXPERIMENTALLY ----

Gibberish.

> h has the Kilogram dimension !!!!!

Utter nonsense.  First of all, kilogram (kg) is a *unit* for the dimension 
of mass, not a dimension itself.  Second, the dimension of ℎ is energy × 
time, _not_ mass.  The possible units for ℎ include J s (joule-second) where 
1 J s = 1 N m s = 1 kg m²∕s² × s = 1 kg m²∕s.

> GOT IT ??!!!

I got that you have delusions of knowledge.

>  and
> nothing F en relativistic  there

That’s gibberish again.  Please do everyone a favor and get yourself an 
English dictionary (and some relaxation pills).  And *use it* (and take 
them) when you post (in English).

> nor anything to multiply it by zero!!

Nonsense, see above.

> Epstein was wrong by claiming that
  ^^^^^^^
Who?

> NO MASS CAN REACH c

AISB, no object whose mass is *greater than zero* (m > 0) can travel at c, 
and that follows from the form of the equations for relativistic momentum 
and kinetic energy *for such objects*.

>  MASS OF PHOTONS DOES IT !!!

The mass of photons is *zero*, so photons can and must travel at c.

Or, if you can understand that better, in your (wrong) terminology “photons 
are not masses”.

> the mass of the photon is an exception to the rule that
> no mass can reach c

You have two major misconceptions:

First, that there would be “a mass”; that mass would be the same as an 
object.  Since photons have no (non-zero) mass and are still objects, your 
idea of a moving mass, instead of an object *with a certain mass*, is wrong.

Instead, mass m is a property of an object as is its rest energy E₀, whereas 
they are related (as Einstein found) by the equation m = E₀∕c².

Second, since photons have zero mass (m = 0), the momentum equation and the 
equation for kinetic energy for objects that have non-zero mass (m > 0) 
*does not apply to photons*.

> you can see even by experimental  EVIDENCE
> that
> as MASS COMES  becomes  smaller and smaller
> IT CAN REACH -CLOSER AND CLOSER TO C !!!!

AISB twice now (only that I used, correctly, the terms “object” and “mass of 
an object” instead).  Can’t you read?

> old copyright by me 

Copyright has been duly added to the list of things that you do not yet 
understand.

This discussion has to do with relativity; there is a special newsgroup for 
that subject in the Big 8.  In Usenet, you are supposed to post to the 
newsgroup that is *the most specific one* in a hierarchy, so in this case 
*you are supposed to post to* sci.physics.*relativity*.  I had set Followup-
To (F'up2) there, which you ignored.  Please do not do that again.


F'up2 sci.physics.relativity

PointedEars
-- 
I heard that entropy isn't what it used to be.

(from: WolframAlpha)

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Thread

Re: Gravity needs NO Matter "Y.Porat" <y.y.porat@gmail.com> - 2016-02-05 00:14 -0800
  Re: Gravity needs NO Matter Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-05 22:38 +0100
    Re: Gravity needs NO Matter "Y.Porat" <y.y.porat@gmail.com> - 2016-02-06 06:34 -0800
      Re: Gravity needs NO Matter HVAC <mr.hvac@gmail.com> - 2016-02-06 08:01 -0800
        Re: Gravity needs NO Matter Mahipal <mahipal7638@gmail.com> - 2016-02-06 08:42 -0800
          Re: Gravity needs NO Matter "Y.Porat" <y.y.porat@gmail.com> - 2016-02-06 10:11 -0800
            Re: Gravity needs NO Matter Mahipal <mahipal7638@gmail.com> - 2016-02-06 10:22 -0800
          Re: Gravity needs NO Matter "Y.Porat" <y.y.porat@gmail.com> - 2016-02-08 10:39 -0800
            Re: Gravity needs NO Matter Mahipal <mahipal7638@gmail.com> - 2016-02-08 11:06 -0800
              Re: Gravity needs NO Matter "Y.Porat" <y.y.porat@gmail.com> - 2016-02-08 22:32 -0800
              editen sujet noTthaTguY <abu.kuanysh05@gmail.com> - 2016-02-09 10:14 -0800
        Re: Gravity needs NO Matter "Y.Porat" <y.y.porat@gmail.com> - 2016-02-06 10:00 -0800
      Re: Gravity needs NO Matter Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-06 17:22 +0100
        Re: Gravity needs NO Matter john <johnsefton288@gmail.com> - 2016-02-06 08:41 -0800
          Re: Gravity needs NO Matter Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-06 18:08 +0100
            Re: Gravity needs NO Matter john <johnsefton288@gmail.com> - 2016-02-06 09:17 -0800
              Re: Gravity needs NO Matter Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-06 18:25 +0100
                Re: Gravity needs NO Matter john <johnsefton288@gmail.com> - 2016-02-06 09:27 -0800
                Re: Gravity needs NO Matter "Y.Porat" <y.y.porat@gmail.com> - 2016-02-09 10:45 -0800
                Re: Gravity needs NO Matter Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-09 23:31 +0100
        Re: Gravity needs NO Matter "Y.Porat" <y.y.porat@gmail.com> - 2016-02-09 10:41 -0800
          Re: Gravity needs NO Matter Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-09 23:04 +0100
            Re: Gravity needs NO Matter "Y.Porat" <y.y.porat@gmail.com> - 2016-02-09 22:37 -0800
              Re: Gravity needs NO Matter Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-10 20:33 +0100
                Re: Gravity needs NO Matter Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-10 20:44 +0100
                Re: Gravity needs NO Matter "Y.Porat" <y.y.porat@gmail.com> - 2016-02-10 22:57 -0800
                Re: Gravity needs NO Matter Thomas 'PointedEars' Lahn <PointedEars@web.de> - 2016-02-13 19:41 +0100

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